texts: How does a two-stage supercharger like the one found in a Rolls-Royce Merlin work? Does the pilot have any control over it?


texts:
Could a helicopter support a detachable wing with no controls on top of the rotor head in place of a radar dome? Could the rotor head be made to support more weight? Would it be more fuel efficient at higher speeds, add a level of redundancy, or increase speed?

I did consider clearance and the drawn pictures is not to scale. The wing may need to be drawn longer, further back or placed higher. This would be a payload in itself for extending the range of the helicopter under lighter loads.

A second feature is that the wing could be made to catch the vortex left by the rotor blades in flight increasing air pressure under both the rotor blades and rotor wing.

Similar to the way ducks fly in a v formation the wings would also take this advantage from other helicopters with this extra wing for extra lift.

Could extra lift be created from the rotor wing, the vortex ring redirection and /or flight in a V formation?


texts: Why can a localiser be used without a glideslope, but not vice versa?

texts:
An ILS consists, at its most basic, of two components: a localiser (to provide lateral guidance) and a glideslope (to provide vertical guidance).  The two are typically used together, for an ILS approach, but the localiser can also be used on its own, for a localiser-only, or simply localiser (LOC for short), approach (for instance, if the glideslope is inoperative or nonexistent, the aircraft lacks a functioning glideslope receiver, or the pilot is shooting a back-course approach).  For a localiser-only approach, the pilot uses a specified series of navigational fixes to mark off each segment of the approach; each of these segments has a specified minimum safe altitude (which is shown on the approach plate), and the pilot uses this information, and their onboard baroaltimeter, to maintain terrain clearance during the approach.

While localiser-sans-glideslope approaches are quite common, there are, to the best of my knowledge (feel free to correct me if I'm mistaken here), no examples of the reverse: a glideslope-sans-localiser approach, where the pilot uses the glideslope for vertical guidance but relies on ground- or satellite-based navigation fixes for lateral guidance.

What allows the use for an approach of a localiser without a glideslope, but not a glideslope without a localiser?


texts: Which airplanes are exempt from Europe's 2015 CPDLC (Link 2000+) requirement?

texts:
In February 2015, all flights above FL285 in EU airspace are required to have CPDLC/Link 2000+.

However,  I have been told by an avionics provider that some aircraft types are exempt from the requirement.  Where can I find the complete list of exemptions?


texts: How does a supersonic jet engine differ from a subsonic jet engine?

texts:
All jet engines have the same method of air flowing into the engine, which is compressed and ignited.

What can engine designers do to make an engine design create more thrust? For example, what is different when comparing the Olympus engines on the supersonic Concorde to the CFM56 engines on a 737?


texts:
I have recovered some spotting pictures that I made long ago and I came to realize an upper prominence in the fuselage of this Norwegian Boeing 737. I don't remember to have seen it in other 737s.

Does anyone know what is it and its purpose?


texts: If the airport reported BKN002, would that prevent performing a DH 259' approach?

texts:
According to this Instrument Approach:

The published Minimums are a Visibility of 1300 m, and a DH of 259 feet.

In accordance with ICAO, would the Visibility and Ceiling be above the Published Minimums to be able to execute the approach or only the Visibility?

For example, if the airport reported BKN002, would that prevent from performing the approach?

On this approach, Jeppesen explicitly states "CEILING REQUIRED", would that Mean that Both Visibility and Ceiling (Broken or Overcast) must be met to execute the approach?


texts: How does the Learjet cabin pressurisation system work?

texts:
In one of the MAYDAY Air Crash Investigation episodes (about the Payne Stewart crash), the flight's emergency manual had the following information under the cabin pressurisation section:

  NOTE: At 10,000 (± 500) Feet Cabin Altitude, control pressure to the
  outflow valve is trapped. This deactivates the Automatic Mode and
  stops cabin altitude from rising higher if the failure is in the
  automatic control system.

What does it actually mean? As the NTSB investigators mentioned, it sure does sound confusing.


texts: I've known that military aircraft with small wings can fly very fast, while commercial aircraft with big wings cannot fly as fast. Why is this?


texts: How is lift provided by a wing affected by propeller wake?

texts:
Does the lift of that section of the wing which is in the wake of the propeller increase (because the airspeed in that section is higher)?

If yes, is this fact used actively to improve the lift capability?

Or does it decrease significantly because of turbulence and an overall disturbed airflow on the wing surface?


texts: How to pick a good airfoil based on Cl and Cd

texts:
Let's assume I have 10 different airfoils graphs of Cl x Aoa, Cd x Aoa and Cl/Cd  x Aoa. How do I pick the best one that will give me the most efficiency (the longest flight time)?

I understand the information that those graphs provide and IMHO I think I should always pick an airfoil that has the best Cl/Cd ratio at Aoa (alpha) of 0 since at 0 the drag is usually the least. This is my "common sense" but nobody says this on the internet so I am pretty sure I am wrong!

So based on the three graphs I have of each airfoil, what math should I do in order to get the most efficient (more flight time) airfoil?

PS: the plane will be a floater/slow flier/glider/sailplane. Of course it will be a slow plane cause my focus is on efficiency and fast planes usually are not efficient.


texts: In the UK, which ATS unit would be responsible for CTR entry clearances? Would the approach controller issue them, or would the approach controller need to co-ordinate a clearance from the aerodrome controller? If the former, I assume the approach controller would pre-note the aerodrome controller?


texts: What was the first airplane fitted with a hydraulic system?

texts:
What was the first airplane fitted with hydraulic system?

Where was it used?

What are the fundamental differences between the first systems and those that are used now?


texts:
I was watching a commercial jet and the vapor trail was moving and disappearing very quickly. I should note that it is currently 61 F on the ground, but the morning has been cool. (Min 34 F) I don't know what vapor trails do under certain conditions, but I would assume that in warmer weather the vapor trail would completely disappear more quickly, but that doesn't seem to be the case in the summer. Anyway, the weird part was when the vapor trail completely disappeared or cut off. The plane stopped producing a trail for about 15 seconds and the plane was hard to see during this period. After that the trail reappeared and resumed as normal. I also noticed that the trail hung around much longer and dispersed more than all the other trails from planes that recently flew by. Perhaps the plane entered an area of air that was different in temperature than the air around it. Has anyone seen or heard of this and have any idea why this would happen?
Thanks


texts: What type of jack is the flight interphone on transport category aircraft?

texts: Recently became an A&P and part of my job is to be on the ground communicating to the pilots during push backs. Started shopping for a headset and have seen various ones with different adapters and jacks. What size jack would work on the flight interphone  on e.g. a B777?


texts: How do I know which airports have ILS and for which runways?

texts: I have been into flying for years but something I can't figure out is how do I, as a pilot, know if an airport I am going to has ILS, which runways would have it and why do only some have it but the other side of the same runway does not?  (I.e. RWY 9 has ILS but 27 does not and they use same frequency.) Do I have to look for something specific like localizer vs localizer DME etc.?


texts: What is the difference between GPS, GNSS and RNAV?

texts: I would like to know the fundamental difference between GPS, GNSS and RNAV. How are they related each other? Are all/some of them synonyms?


texts: What privileges do off-duty pilots have in their own airline?

texts:
I was recently in a Delta flight where there were two off-duty, but in-uniform pilots flying along with the passengers. One of the pilots sat in the First Class section of the airplane and the other sat in the Economy section. After the seatbelt sign came off, the pilot in the Economy section moved up to the First Class where there was apparently an empty seat.

This led me to wonder: what privileges do off-duty pilots have in-flight?

I am limiting this to only US to keep it from being "Too Broad".


texts: Why are vertical stabilizers always at the rear of an airplane?

texts: Sharks and whales have them in the middle of their body, so why not planes?


texts: How much does (or can) the fuselage of a long aircraft flex?

texts:
How much will the unsupported ends of an airliner's fuselage droop in level flight?

In turbulence, how much vertical movement will they experience relative to the wing?

And finally, in extreme conditions, what is the expected limit of such movement?

Is it a movement of a few millimetres or a few centimetres, or more than that?

I assume any horizontal flex - or torsion along the axis - will be much smaller.


texts:
How often does an airline pilot use the rudder pedals during flight? Is it only during takeoff and landing?

I am interested to know the rudder pedal usage time in minutes per average short range flight (A320, Domestic flights, ~1-2 hr flight duration). When on autopilot, the rudder control will be automatic. There are even automatic rudder trim features for most of the commercial aircraft.


texts:
I'm having a class about Database management system, and the professor gave us a project regarding Air traffic control system. The exact assignment is to "Design and create a system which can manage informations of Air Traffic Control System, summarize entities and how system works".

I'm not asking you to do this for me, what I would like to know is

what should i know about air traffic control systems?
how does it work?
what are the entities involved in it?
what is an air traffic control system?


texts: Why are the top speeds for jet engines higher than for propellers?

texts: I realize turbines are more efficient than piston engines, but if that were true, then why don't turbo-props reach jet speeds?


texts: Apart from Kenya, what are the current dangerous / unsafe airspaces?

texts:
Notams are regularly released to warn about unsafe areas, e.g. Kenya:

  A0040/15
  - SECURITY .. UNITED STATES OF AMERICA ADVISORY TO U.S. OPERATORS
  CONCERNING POSSIBLE ATTACKS WITH MAN - PORTABLE AIR DEFENSE SYSTEMS
  (MANPADS)

  ATTENTION U.S. OPERATORS: INFORMATION INDICATES THE POTENTIAL FOR
  TERRORIST ATTACK AGAINST U.S. AND WESTERN INTERESTS IN KENYA.
  WHILE SPECIFIC DETAILS ARE NOT AVAILABLE, ONE POSSIBLE TACTIC WOULD
  BE AN ATTACK USING MAN - PORTABLE AIR DEFENSE SYSTEMS (MANPADS),
  SUCH AS THOSE USED AGAINST AN ISRAELI AIR CARRIER DEPARTING FROM MOMBASA,
  KENYA ON NOVEMBER 28, 2002.
  THE DEPARTMENT OF STATE HAS ISSUED A TRAVEL WARNING FOR KENYA REGARDING
  TERRORIST ATTACKS.

Is there a list of these hazardous airspaces, or a site than can be checked without searching in Notams from around the world? Is there a ranking of the hazards?


texts: How often is the cabin air replaced in A320?

texts:
One of the A320 pilots told me that there is an icao rule that air should be replaced every 90 seconds?
Is this true ? can someone give me a supporting article for the same


texts: What components of the Boeing 787 are made out of titanium?

texts:
Inspired by the question, Why is the 787 tail cone made out of titanium?, I want to know what other parts of a Boeing 787 are made out of titanium.

We now know, the APU exhaust cone is made out of titanium, but what else?


texts: Do I need a license to flight test a homebuilt seaplane at very low altitude?

texts:
I am asking this because me and my friends are building a homemade seaplane or boat whatever you want to call it. It's not designed for long-range or high-altitude flights. We're not going to fly at a typical altitude of normal planes/seaplanes but we're just flying it to test it. Do we require a license to fly it?

This is in Canada and it's a manned aircraft.


texts: How can aircraft determine true north for inertial navigation systems?

texts: Aircraft use GPS and inertial navigation systems in combination. Sometimes INS needs alignment (i.e. to be told where it is AND what orientation it has). How can an aircraft be be aligned to true north for proper INS alignment? Are markings at the parking location good enough?


texts: What is the record for the highest achieved landing speed?

texts:
The emergency landing of Hauptmann Siegfried Heltzel in a Lockheed F-104G Starfighter at the Nörvenich Air Base on 02 June 1965 is often mentioned as the record for the highest landing speed. The emergency landing became necessary after a mid-air collision with a Dornier Do-28. The landing speed is given as 435 km/h (270 mph). According to German-language sources, this value refers to touchdown; however, I didn’t find any source that mentions whether it corresponds to airspeed or ground speed.

Is this (still) the absolute record?

I am mainly interested in comparable parameter values of similar incidents in order to judge whether the above-mentioned emergency landing really was (or still is) an absolute record. Nevertheless, I would be glad about any information on possibly record-breaking incidents in closely related categories.


texts: Drag estimation of Xfoil and Vortex Lattice Method?

texts:
I have been working on building a software to estimate lift and drag properties of a fixed wing being tested at a wind tunnel. The setup is a low AR wing with NACA0012 profile and 0.3m chord, with 0.4 span lengths being tested at speeds up to 20m/s. For modeling, I'm using Vortex Lattice Method (VLM) for estimating $C_L$ and $C_{Di}$ of the wing. In addition to this, I am planning to use Xfoil's predictions for estimating $C_{Dp}$. I am aware this is a crude estimation, but my starting point, nevertheless. With this configuration in mind, I've been running a few tests to validate the modeling behavior; but there have been some observations that I cannot wrap my head around:

For drag, I have the following plot as my baseline expected behavior. However, XFoil estimates show an opposite behavior for parasitic drag ($C_{Dp}$). When I change the Re from 250,000 to 500,000 (doubling the speed) (at 12$^{\circ}$AoA), $C_{Dp}$ goes down from 0.038 to 0.026. I am aware the drag force is still greater when $C_{Dp}$ is multiplied by dynamic pressure, but decrease in $C_{Dp}$ seems counterintuitive to me.

Continuing off from the figure above, I expected induced drag ($C_{Di}$) to significantly decrease as speed increased. However, both of the VLM packages I experimented with (PyVLM and AeroSandbox) give me constant ($C_{Di}$) at varying speeds. Is this a huge inaccuracy of VLM or am I interpreting something wrong?


texts: Why did upward turning propellers in the F-82 Twin Mustang cause a loss of lift in the center wing section?

texts:
In the Wikipedia article on the F-82 Twin Mustang it says:

  After a month of work North American engineers finally discovered that rotating the propellers to meet in the center on their upward turn created sufficient drag to cancel out all lift from the center wing section, one quarter of the aircraft's total wing surface area. The engines and propellers were then exchanged, with their rotation meeting on the downward turn, and the problem was fully solved"

Why did this direction of propeller turn cause this problem?

Image source: http://www.au.af.mil/au/afhra/wwwroot/photo_galleries/aaf_wwii_vol_vi/Captions/078_Experimental.htm
(This image or file is a work of a U.S. Air Force Airman or employee, taken or made as part of that person's official duties. As a work of the U.S. federal government, the image or file is in the public domain.)


texts: Is the turn radius at fixed bank angle really independent of aircraft type?

texts:
I'm curious about the relationship between an aircraft's turn radius and the bank angle. This formula describes the relationship between the two:
$$ R = \frac{v^2}{g \tan(b)} $$
Where $R$ is the turn radius, $v$ is the speed, $g$ is acceleration due to gravity and $b$ is the bank angle.
This formula is found dotted around the internet (with variations depending on units used) examples include here and here.
My question is, why is there no reference in the formula to the physical characteristics of the aircraft? Does the relationship between turn radius and angle-of-bank really have nothing to do with aircraft weight, wingspan or aerofoil design? Does the same formula really hold true for both glider (sailplane) and large passenger jet?
Hoping for an explanation with no maths please!


texts: How is the lighting panel of an Airbus A340 designed and how does it work?

texts:
I'm trying to simulate the light switch panel of an Airbus A340 with real electronics components for a model in scale (I'm doing the electronics lights with leds).

Taking a look at this PDF (page 129), I would imagine that there are several switches for these lights. But when I searched on Google Images, I couldn't find a photo of this panel, only some diagrams of A320. I never saw one that I could identify.

Question:
How is the light switch panel and/or where can I find a picture or diagram?

UPDATE 1:

Is it something like this?

UPDATE 2:

I'm seeing that some switches have 2 or more points? For example NAV & LOGO, what means 1 and 2? Off, NAV or both?

And what about STROBE-BEACON, what does "AUTO" mean?

By the way, I couldn't find the "CARGO" light, and I think that "DOME" are the Landing Gear Bay, but what does BRT/DIM mean?

UPDATE 3:
I was reading this:
AIRBUS A340 - Flight Deck and System Briefing for Pilots
But I couldn't find an image about the navigation panel.


texts: How to find out what engine a plane had in the past?

texts:
I want to find out what engine a specific airplane had in the past.
For example for the Airbus A320. The sources which I've found tell me there were different engines. CFM56-5A, CFM56-5B, IAE V2500 etc. Let's say I flew in 1999 with Lufthansa. What engine did I most likely fly with?


texts: How do individually controlled feather like winglets work?

texts:
I want to know how the individually controlled feather like winglets work on controlling and rolling by reducing drag.(concept of airbus bird's of prey)
I just need a detailed review of the aerodynamics and its mechanics and how it reduce drag and what are its effect on L/D ratio etc as i am a aeronautical student i wish to know more about it on the futuristic design so it can be helpful in my projects


texts: Why are there no cargo aircraft with "flying wing" design?

texts:
From that I have seen so far, the "flying wing" design (like the one of B-2 Spirit and Northrop YB-49) has superior performance but also a few notable problems that make it difficult to use for passenger aircraft:

It is difficult to control, and the YB-49 crashed even when flown by an elite test pilot. However, computer assistance has been implemented for B-2 and I do not think this is a problem any longer.
There are problems related just to the passenger transport: not enough windows, difficult to evacuate.
It also cannot be pressurized as easily as a cylinder but for a majority of possible cargo this is probably not a problem. Some cargo may not require pressurization at all and some may only need partial pressurization like in jet fighters.

Hence I understand that there are problems on the way to the flying wing passenger aircraft. However, why there are no cargo aircraft of this kind around?


texts: What does ATC mean when they refer to "company"?

texts: Listening to LiveATC there are references by various ATC entities (towers, approach, etc) to "company". To what does this refer?


texts: How to compute drag coefficient for falling book?

texts:
The book measures 20 x 20.3 x 1.4cm and I'm assuming it's sealed shut so the pages don't flap open. Mass is 450g.

I want to understand how quickly it would fall if dropped straight down from 10km altitude. I've used a value for drag coefficient for a flat plate perpendicular to the air flow that I got from NASA (1.28) but I'm guessing that a falling book would spin round, slowing its fall, so this value is probably not right - is this likely?

So I'm wondering if it's possible to estimate the drag coefficient to any degree of accuracy. I don't have access to a wind tunnel and I'd rather not drop it off a tower as an experiment. :)


texts: What are effective ways to spot the aircraft ATC specified?

texts:
When ATC instructs me something like "There is a Skyhawk on your 2 clock, 7 miles, 6500". I am not able to spot the target at least half of the time after several ATC reports its position until ATC says "not a factor" or gives me a new heading or altitude assignment.

I am wondering if there is any effective ways to get the aircraft spotting skill? Or knows my limit that it is nearly impossible to see it if it beyond a certain range and give up searching. When entering busy airspaces, the aircraft looking is taking a large portion of cockpit time.


texts: How to fly IFR to an airport without any instrument approaches?

texts: Would I just file an IFR flight plan to the airport in question, and expect to be cleared for the visual approach if there are no instrument approaches at the destination airport?


texts: Can a person with unilateral anosmia in the right nostril become a commercial pilot with a class I medical?

texts:
I had a minor road traffic accident in November 2014, since then I cannot smell through my right nostril, where my left nostril is working normal. I am looking to know if you know any pilot you have met with who has no sense of smell or lost it due to any event like accident in my case and is still flying.
I am interested in FAA and DGCA India regulations.


texts: How are GA aircraft ferried from factories?

texts:
It's relatively easy to transport jet aircraft like Airbus and Boeing: most of them have a long range, and a few hops at most would get them to the owner.

But how would a Cessna manufactured in U.S. be delivered to Dubai? It would not have the range to cross the Atlantic. Taking a brand new single-engine aircraft across a large ocean also sounds very risky (to the occupants). Same story applies to Hawaii.

Getting there may also require many hops (e.g. Texas -> California -> Canada -> Alaska -> Japan -> Taiwan -> Singapore), making the transportation long and costly.

Are they put on trailers and shipped like cargo? If yes, how is the aircraft taken apart? (I'd imagine even the wing span of a 172 would be too wide for roads in many countries)

EDIT: the linked question addresses airliners. I am specifically interested in GA airplanes.


texts: Why do aircraft use 400 Hz AC instead of the 50 or 60 Hz of wall outlets?

texts: Large aircraft electrical systems usually use 400 Hz alternating current (AC), while common household electrical outlets deliver AC at 50 or 60 Hz.  Why the difference?


texts: Where do most fighter jets and combat aircraft mostly get shot? ex: body, wings, engine area etc

texts: I'm wondering where fighter jets mostly get shot. I'm trying to design a plane that might help this issue if most planes get shot in the wings. If they get shot elsewhere I guess I'm going to have to come up with new ideas.


texts: Are fighter jets vulnerable to .50 caliber gunfire?

texts: As I've seen in the movies, could a .50 caliber round shoot down a fighter jet?


texts: How should wake turbulence from aircraft on the ground be avoided during landing?

texts: If a large jet aircraft is holding short of runway 28L while I am landing a single-engine aircraft on runway 28R, how should I proceed with such a landing?


texts: How the pitch of a blade must change along the length so that the blade does not stall?

texts: I have to finish an assignment in the next couple of days. One of the questions asks to show how the pitch of the blade must change along the length so that the blade does not stall. I have no idea what I have to do or how, can someone help me please?


texts: Is reducing V1 a viable option for pilots when the ASDA is shorter than the ASDR?

texts:
Let's say you were planning to ferry some passengers and cargo in a jet but after some calculations found out the ASDR (Accelerate-Stop Distance Required) was greater than ASDA (Accelerate-Stop Distance Available) of the only runway available in the airport. Can you address this situation by lowering V1 speed for the flight and thus shortening the ASDR?

This question has a context. People discuss the effect of a runway length on V1 on this post and seem to agree a runway length has no bearing on V1. In other words, however long runway you may have for your takeoff roll, if an engine fails after V1, you should continue the roll and take off, not the least because you never know you might be able to make a full stop without a runway excursion.

Granted what they say is true, is it as well not permitted to plan a reduced V1 speed for the runway whose ASDA is shorter than the ASDA for a maximum takeoff weight flight of the day?


texts: Why are aircraft of Russian origin not subject to frequent weighing and CG calculations like western aircraft?

texts: Western miltary a/c maintenance requires routine weighing of the plane yearly or during major inspections.Whereas Russian miltary a/c maintenance does not insist on this kind of weighing,so much so that weighing is not part of any maintenance  schedule after initial manufacture ! Can some one give any plausible reason for this anomaly ?


texts:
Let's say you want to perform a turn anywhere from 1 to 90 degrees. Which will cost less energy? A bank or a yaw?

Using the rudder does produce extra drag, because the control surface is deflected for a time.

Using ailerons to bank also produce extra drag, but more than that, at a roll angle the lift direction will not be perfectly vertical. You will either lose altitude (that needs to be regained), or increase speed.

That's why I didn't want to phrase the question as "less drag". Lost energy could be in the form of drag, worse lift angle, lost altitude, maybe other things I haven't thought of.

I'm interested in large commercial aircraft as well as "ideal" aircraft with no adverse-torques (all control surfaces are aligned with the center of mass).


texts: How much does it cost the airline if an aircraft misses its take-off slot?

texts: I was recently watching a TV programme and it said if an aircraft misses its take-off slot it will cost the airline company thousands, roughly how many thousands though???


texts: How do navigation displays depict turn anticipation?

texts: I'm working on a navigation display for a simulation and I want to know if someone can explain me how the navigation display displays the "curved lines" for fly-by waypoints.I know how to calculate the distance needed for turn anticipation and the turn radius but how would a real ND draw this ? I attached a screenshot for the ADMAG2X departure for gatwick from a simulator navigation display but why does the turn start after "KKW02" and "KKW02" is no overfly waypoint ? :)


texts: What is a possible reason for an L-1011 wing fuel tank overflow?

texts: I was on a TWA Charter flight from Boston to Montego Bay Jamaica in 1989.  During pushback from the gate, the right wing began to leak jetfuel (like gallons pouring out of the wing).  They stopped the pushback and the first officer rushed back to take a look.  We didn't evacuate, the fire trucks came, and after the spill was cleaned up on the tarmac, we departed without incident.  Curious if this was a typical mishap on the L1011 or if someone could provide any possible reason for this to occur.  I couldn't believe we were allowed to depart without a detailed inspection.


texts:
Given that several nations had operational carriers by 1920 and biplanes were still in military service, were there any folding wing biplanes?

Wikipedia: United States first purpose built aircraft carrier, USS Langley (1920), note no biplanes have wings folded.


texts: For an electric airplane are propellers the only option for propulsion?

texts:
This is for an electric airplane (so no fuels for combustion):

Are propellers the only option?
Is there a turbine-jet possible with only air intake, electrically compress, and  a turbine and nozzle and get equal or more thrust than a propeller like a water-jet but then with air?


texts: Trying to find the vertical acceleration by subtracting weight from lift

texts:
I'm trying to determine the vertical acceleration component of a plane with the following specifications:

Density of air: 1.29kg/m3
Speed: 33 m/s
Wing area: 13.97 m2
Lift Coefficient: 1.5
Mass:560 kg

Lift formula : 1/2*1.29*33^2*13.97*1.5 = 14718 N.

(Lift-Weight)/Mass = (14718-(560*9.8))/560 = 16.48

From this I deduce that the plane has a vertical acceleration of 16.48 m/s2 which I find way too much.(I was expecting to get somewhere from 3 to 5 m/s2)


texts: Why are twin engine airliners more fuel efficient than three or four engine airliners?

texts: It is said that given roughly similar aerodynamic and engine technology that twin engine airliners are more fuel efficient than 3 or 4 engine airliners.  Why is this?  The twin engine airliners tend to have more excess power so I'm thinking that they can climb faster and fly higher, lowering the amount of time spent climbing (uses more fuel than cruise) and lowering fuel consumption during cruise.  I suppose that fuel consumption is less while the engines are idling as well.  Are there other factors that go into the 2 vs 3 vs 4 engine fuel consumption issue?


texts: Is it legal to take off with an iced windscreen?

texts:
Looking at this video on Youtube, I'm wondering if it is actually legal to take off with a windscreen iced like that?

For VFR this is a no go, but what about IFR and under what conditions?


texts: Watching videos of jets taking off from a carrier, it appears the pilot is holding a hand grip as the jet is catapulted along the deck; then there is 'jerk' type motion as the jet leaves the deck with the pilot then taking control.  Could you please describe what happens during the take off.  It looks like a really rough ride for the pilot.


texts: Why were early aviators' trousers flared at the thigh?

texts:
For example, these dapper outfits:

(Credit History Bunker)

What purpose does the extra volume down to the knee serve? Why don't modern pilots wear similar jodhpurs?


texts: Airbus control architecture - where does the actual autopilot live?

texts:
I'd like to ask for confirmation about the A320 (and, generally, Airbus family) control architecture. The book Aircraft Systems provides the following
overview of A3XX computing architectures:

Focusing particularly on the A320 family, are the ELACs and SECs merely actuator controllers for the control surfaces, or do they also carry the autopilot flight control algorithms? Or is the "autopilot" a separate entity, which feeds desired control surface positions to the ELACs and SECs (i.e. these latter are simply "slaves" to the autopilot)?

This picture from an A320 Operating Manual makes it seem that ELACs and SECs are autopilots themselves (i.e. there is no separate entity that is the autopilot that feeds them signals):

However, the same manual has another figure which makes it seems that indeed there is a separate autopilot entity:

If the autopilot is indeed a separate "master" entity which feeds desired
control surface position signals to the ELACs and SECs, is this a concept that generalizes to the rest of the Airbus family? Where does the autopilot software then live?


texts: Do we fly full size aircraft with video game style joysticks?

texts:
Are there planes with electronic joysticks as shown below?

RC airplanes are incredibly effective at using this technique. For actual planes it would remove the need for rudder pedals and a stick along with potentially being easier to get used to.

Are thumb controlled sticks used in aviation? or is there a reason to why they aren't used?


texts: Why isn't the An-72 / Boeing YC-14 configuration used for airliners?

texts:
Why aren't there a lot of passenger airliners (short flights) using this configuration, since using Coanda effect by blowing wing's extrados is much safer in harsh weather, and would provide extra safety during gusty landings and takeoffs?

I guess extra weight, induced drag, and engine maintenance height may be good reasons, but is it enough to eliminate this solution in the economy/safety equation?


texts: Why don't airport have heated runways to deal with winter conditions?

texts: It is for years that I ask myself as a frequent flyer why there is no Airport using a system, like built-in electrical resistances on Runways to avoid Delays/Cancellations and even closing Airfields during winter? The costs of such a system would be for sure less than closing an Airfield for one day.


texts: What is the certification process for a new propeller blade design?

texts:
I am wondering whether a propeller blade design (say from Hatzell) is submitted to a specific agency for testing and approval, and if these designs are then registered. Looking through Hatzell's product list, I would assume that there are requirements on specifications (material and form), but there must be some allowance in this?
I am also wondering if those documents are then publicly accessible, like a patent would be?


texts: What happens when autopilot and propulsion settings do not match?

texts: Autopilots used in piston GA usually do not have throttle control. They only manage the control surfaces. However to trim an aircraft one needs to play on both throttle setting (and more physically, thrust) and control surface deflections (aerodynamic forces). What happens if the autopilot cannot trim the aircraft due to the propulsion settings? Is there any alert from the autopilot for the pilot?


texts: Can anyone explain why and how flames shot out of an F/A-18 as it crashed?

texts:
Can anyone explain why and how flames have shot out of the left engine of this F/A-18, whose left engine was apparently not generating power, the picture is here. And the source website where I got the infomation from is here.
The accident happened in Lethbridge, Canada in the July of 2010. Below is a comment posted on the forum in response to the post of the crash on ED forums:

  It was a fuel control problem (sticky piston) on the right engine, isn't #1 the left? The open nozzle of the left engine indicates that it's either a) at idle or b) at full power/burner which it was in this case as the pilot was executing a high alpha pass at the time.

The comment about the left engine not hasving power is here:

  The left engine has the nozzle fully open, showing that #1 engine was developing no power.


texts: How do I convert my FAA PPL to the equivalent in the UK / Europe?

texts:
I am returning to the UK and want to convert my FAA PPL to a UK PPL. Does anyone know the process for doing this?

I am getting lots of conflicting information.


texts: For taking-off and landing in a DHC-7, what elements can be used in writing a novel?

texts: What cockpit elements can be used in writing a novel for taking off and landing in a de Havilland Canada Dash 7 from a short runway in Rothera, Antarctica? Including the names of those switches overhead, and the throttle and the steering stick/wheel?


texts: What Is this on the fuselage of The Fokker F100?


texts: Why do tailplanes provide down force, if not for longitudinal static stability?

texts:
We can see that most conventional aircraft have their horizontal tail surfaces arranged to provide a down force. This question asks if that is required for static longitudinal stability, and the answer is: not necessarily.

But if static stability is not the reason, what is? Or is it just a meme indeed?


texts: Is there an in-flight built-in-test in an airplane?

texts: Is there any in-flight built-in-test in the airplanes separate from the in-flight monitoring?


texts: Why aren't 757 scimitar winglets flush with the ailerons?

texts:
Over my many past flights aboard 757s, I have seen changes being implemented with their design. One of which was notably their refit of scimitar winglets. Although one of their most notable characteristics is the extended pointy edge on their tip, I have noticed that the inner edge of the winglet (past the wing position light) does not run flush with the aileron, unlike that of the older 757 winglets.

What is the reason behind this design exactly?

Thanks!

*Please note that the first 3 photos below are of the scimitar winglet and the last is of the original older design

Photo credits: First 3 photos are taken by me personally. Last one is from: https://www.flickr.com/photos/33415137@N06/6151948806


texts: Can a colour blind person pursue a career in Commercial Flying?

texts: I have been an ardent aviation geek since childhood and always wanted to be flying commercially. But sometime later during a medical examination through Ishihara plates test I learned that I am color blind. I have been reading quite a lot about colour blind people are considered to be medically unfit to fly. So I just wanted to confirm if this is true or should I go and take some additional test before I let go of my dream.


texts: When does an UAV need an internal structure?

texts:
I´ve seen some UAV models without internal structure (stringers, longerons and frame). I guess the drone´s shell is the frame itself. So what is the best approach to calculate the shell thickness to avoid using a more complex internal structure?

Data:

Wingspan: 2.4m
Length: 0.9m
AR: 11
Speed: 16m/s
Estimated weight: 3.2 kg
Fuselage and wings materials: carbon fiber


texts: Why doesn't flightradar show many flights going over China?

texts:
I use FlightRadar to track some flights. I am surprised to see that there are very few or no flights at all going to air fields of china.

Is my observation correct? I really doubt that this is correct.

If its true what is the reason behind that?


texts: How does the NATO code name system work, are they just random names, or is there some sort of rule(s)?

texts: When an aircraft is designated a NATO code name, are there a certain rule(s) that contribute to the naming of an aircraft.


texts: When using the Source Panel method and dealing only with sources and sinks, why do lift and drag equal zero?

texts: I am trying to deal with the airfoil with the "Source Panel method", and when I try to calculate the lift and drag, they always equal to zero. And I have found an explanation in some articles, that sources and sinks don’t create any drag/lift. But I don't understand the reason. Could someone give me some explanation?


texts: Why do all the rings of MH370's transmission locations have the same origin point?

texts:
This question originates from the video "The Vanishing of Flight 370", by Lemmino.

At 6:00 he says

While these transmissions did not contain any information about the flight's position, investigators were able to measure the distance between the satellite and the aircraft at the time of each transmission, based on how long it took those transmissions to be sent and received. This generated seven rings of possible locations, from which seven of these transmissions are thought to have originated.

And this diagram is displayed:

But something about the visual strikes me as odd: don't satellites move? I thought they had to keep orbiting or they would crash. So why do these rings of transmission locations, taken over a roughly six-hour period, all show the satellite above the exact same place? Clearly something about my reasoning must be wrong if the investigators never considered it.
(I'll understand if this belongs more on Space Exploration stack exchange.)


texts: How do SIGMETs arrive in a cockpit on a modern longhaul flight?

texts:
What is todays medium of choice (Voice Radio, ACARS,CPDLC,…) to receive SIGMET messages on a commercial longhaul flight, for example from continental Europe to the US westcoast?

Are there any differences in the regions that are passed (European Landmass, Oceanic, North American Landmass)?


texts: I was flying the other day and heard tower say to another aircraft, "square the base". What does it mean, and when might a controller say this?


texts: Is there an ideal lift distribution for human-powered aircraft?

texts:
Is there an obvious, ideal lift distribution for human-powered aircraft?
Elliptic or Bell (unloaded tips) distribution?
For this who will tell the Bell distribution, I have a counter-question ready, why don't put wires to wingtips to reduce bending moment at root and use elliptic distribution?
So what is the purpose of any Bell distribution, if the wing is designed correctly?


texts: Why don't combat aircraft have rear-facing *laser* weapons?

texts: This question is similar, but only talks about guns. I don't mean a laser that is going to destroy the plane, but why aren't rear-mounted, rear-firing lasers that can blind a pilot a thing? Most of the concerns about weight and relative velocities from the other question disappear with a lighter-weight laser that is firing light.


texts: When conducting a circling approach, how close do you have to stay to the airport (especially with the new FAA requirements)?

texts: I heard that the FAA recently changed how they calculate the protected area for circling approaches, and it looked quite complicated because it changes based on altitude and speed, etc.  Can you please explain how you know when to use the old -vs- new criteria, what distance you can safely use, and how to figure it out quickly when flying?


texts: How can I convert a Peruvian pilot's license to one that will let me work in the USA?

texts:
My fiancé just became a U.S. resident. He's originally from Peru and is a helicopter pilot with some airplane experience as well. He has more than 8000 hours flying helicopters and around 150 airplane hours. He's an instructor pilot in Peru and currently works for the Peruvian Air Force.

I would like to know what does he has to do in order to work in the United States. Is there a different certification he has to get in order to fly either a commercial plane or an helicopter? Where can i get more information about it?


texts: I've always wondered if flying is bad for your health mainly because when you fly the air pressure changes a lot and i've always thought that, that can lead to negative side affects. So can someone please tell if there are any negatives to flying which may affect your health. And are there any reasons of why flying is good for your health??


texts: How can the 3M22 Zircon receive commands at high speeds?

texts: According to its Wikipedia article, the scramjet-powered 3M22 Zircon missile is capable of achieving speeds of up to Mach 9, at which a plasma may be created around the missile. The article further mentions a plasma stealth effect "absorbing any radio waves" but then goes on to say it "exchanges information in flight and can be controlled by commands". If the plasma cloud around it absorbs all radio waves, then how can it still receive commands?


texts: Could flaps replace spoilers by deflecting more than 90°?

texts: Could flaps replace spoilers by deflecting more than 90° after touchdown?


texts: Does someone know anything about APU bleed air supply in this pic?


texts: Does the 747-8 / A380 nose-wheel encounter more weight during braking?

texts:
Given that the nose wheels of both the Boeing 747-8 and Airbus A380, as is true for almost all aircraft, are not equipped with brakes, do they encounter more weight during braking?

If so, how much more at maximum safe landing weight?

If they were equipped with brakes, would they encounter more weight during braking and what other effects would ensue?


texts:
I know that the answer will probably be no, and this question might sound silly, but I wanted to think outside of the box.

If engine air intake comes from the front, and is pushed out through the back, what happens if the tailwind is so strong that the opposite happens, and the air is pushed in through the back of the engine? Will it create reverse-thrust? Is this dangerous?


texts: Why does the Boeing 737 have a pitot tube on the tail?

texts:
From this link:

Can anyone explain why the Boeing 737 has a pitot tube for the elevators? Wouldn't the airspeed be measured the same from the front of the airplane and the tail? Is the airspeed measured at the tail view-able from the cockpit?


texts: Redundancy in Integrated modules avionics

texts:
What kind of hardware redundancy is used in integrated modules avionics based architecture for EFIS displays running on a single processor?

My question is specific to redundancy of display hardware driving three different displays. I'm not sure if such kind of thing is implemented before, but I'm trying to run three different displays with a single processor.


texts: I'm interested in how Part 135 operators pilots, ops directors, etc., view the Argus, Wyvern, and IS-BAO ratings - and how you view the differences in tiers - Platinum, Gold +, Gold, Wingman, Registered, Stage 1, 2, 3, etc.  Anything you can share in terms of their value in conveying the safety of the operator to the consumer. Thanks!


texts: What would happen if I had a type rating for an Airbus A320 and applied for an airline that has an A320 and other aircraft?

texts: Let's say I have a type rating for an Airbus A320 and applied for lets say delta. So we know that Delta has an Airbus A320, Airbus A330, Boeing 737, Boeing 777, etc. Suppose I have an Airbus A320 type rating and I applied and passed the interview and everything, will they automatically assign me to the Airbus A320 considering I already have an Airbus A320 type rating , or not? (By Airbus A320, I mean the Airbus A320 family which include the A318 A319, A320, A320 neo, A321, A321neo)


texts: With helicopters, is normal landing or auto-rotation landing any different when landing on water?

texts:
I noticed something from investigating my other answer to a not-really-related question.

A wiki article here says:

  The "water bird" emergency landing is a technique developed by the Canadian Forces to safely land the Sikorsky CH-124 Sea King helicopter when one engine fails while flying over water. The emergency landing technique allows the boat-hull equipped aircraft to land on the water in a controlled fashion.[37]

Which leads me to the obvious question: Is landing any different for water landings? If so, how?

I don't know much about helicopters. For a normal landing, I assume they just hover down and I thought the same thing would be done for a water landing. But the wiki article I read implies that something is different.

For auto-rotation without any engine power, apparently there is a flare at the end. Is this flare done any differently when landing on water?

Basically, the spirit of the question is, how is landing different (if at all) on the water, whether powered or not?


texts: Is it ever possible to auto-rotate with a missing rotor blade?

texts:
A couple of years ago a UH-60 managed an auto-rotation landing with "badly damaged rotor blades."  (Couldn't find further details on that incident.)

Is it ever possible to auto-rotate in a helicopter that has lost a segment or entire blade of a main rotor?

My guess is that, in general, it would be impossible to control the lift asymmetries and such in-flight damage would always result in an uncontrollable crash.  If that's correct, then what about the special case of a helicopter with 4 or 6 main rotor blades, and if it were possible to jettison the blade opposing the one that was lost or damaged?  (Are any helicopters equipped with an emergency ability to jettison rotors in flight, other than the ones with vertical ejection seats?)  Is it known whether such a damaged rotorcraft can reliably auto-rotation in that scenario?


texts: Can you help me identifying this circa 1910 airplane with tail number 72?

texts:
Circa 1910 airplane with tail number seventy two

(Click for larger image)


texts: What are the effects of shockwaves on normal and supersonic aircraft?

texts:
What are the effects on the speed of the plane, does it effects the body of the plane, and do shockwaves cause major damage to the plane.

I know that flying at Mach 1 is really risky, but what's the actual effect of the shockwave?


texts: What is the resolution of airport ground radars?

texts: In largest airport a ground radar is used to handle safely aircrafts on taxiways and on runways, which should be the characteristics of this kind of radar ? What about its range and bearing resolution ?


texts: Why does the rotor thrust decrease at smaller tip clearance for shrouded rotor?

texts:
Consider this system, rotor with shroud:

From this research, we see that: at the same rpm, the rotor thrust decreases,the shroud thrust increases as tip clearance decreases. But why does the rotor thrust decrease at smaller tip clearance? You can see author said at page 11:

  "Note that the increased inflow in the plane of the rotor at smaller tip clearances causes a small reduction in the effective angle of attack seen by the rotor blade, which results in a small decrease in the rotor thrust."

I understand that the inflow increases that will causes a small reduction in the effective angle of attack seen by the rotor blade. But final question: why do we have increased inflow at smaller tip clearance?


texts: Do airlines employ FAs from their destination countries?

texts:
I'm watching a documentary about daily business of an airport.

There was a crew briefing for a Lufthansa flight from Germany to India, and as there was an Indian FA, the briefing was held in English (i.e. he didn't speak German).

While it is advantageous to have an Hindi speaking FA on board of a flight to India, I wonder why he doesn't speak German.
To me, it seems unusual to have an employee living here, but not speaking our language. (Though this is possible.)

So, my question is:
Do airlines employ people in their destination countries, for example to have FAs speaking the language of the destination country? Or is there some kind of exchange project?


texts: On SIGWX (significant weather) charts, what does **/** mean?

texts:
On SIGWX charts, it shows pairs of symbols with, say, */** or **/**. I know what the symbols mean on either side, but why are there two, and what does the slash indicate?

Would love good resources that explain more, too.

Example chart here, from the FAA sample questions (caution: 37 MB download), Figure 20, over Southern California.

I’m also interested in knowing what a dot with R underneath means.


texts: How does a jetstream boost an aircraft's speed?

texts:
Jetstreams are streams of high-moving west-to-east winds (200mph to 300mph, source) which most pilots are trained to use to cut down on their fuel costs (source). In the same linked article, it mentions private jets almost always fly at maximum speed anyway, even when on a jetstream.

Assuming a pilot maintains the same airspeed before and after entering a jetstream, how much would be the expected change in groundspeed in practice? Is it just the airspeed plus the tailwind?

I imagine it depends on the type of the aircraft, so consider only a typical commercial airplane (Boeing, Airbus? I'm not sure which one is more typical).

I'm just curious in knowing how the plane's speed is affected and why it changes that way.


texts: What aircraft might have white wing tip lights?

texts: I live near O'Hare airport and see hundreds of planes every day.  This evening a plane flew past that did not have the standard red - green wing tip lights.  It was white only on both sides.  It caught my attention because of that, and because the plane was unusually quiet...not silent, but quieter than most everything accept the smallest private planes.  Any suggestions as to what I saw?


texts: Do aircraft performance figures include corrections for areas with especially strong or weak gravity?

texts:
The strength of gravity at the Earth's surface is not constant, but varies from place to place by as much as a few percent:

(Image by NASA.)

As a result, an identically-loaded aircraft weighs less in (for instance) southern India, Uyghurstan, the eastern Caribbean, or the Hudson Bay area than it does in (for instance) Indonesia, Greenland, Liberia, or the Russian Far East, which should (in theory, at least) affect its operations in several different ways:1

An aircraft in a lower-gravity region won't need to generate as much lift in order to become, or remain, airborne, allowing it to take off and land at slightly lower speeds, to climb slightly more steeply, and to cruise at slightly higher altitudes.
An aircraft in a lower-gravity region can be loaded slightly fuller without exceeding its maximum allowable takeoff weight (potentially giving it a range advantage over an aircraft launched from a higher-gravity region, if the extra capacity is used to carry more fuel), and can land slightly fuller without exceeding its maximum landing weight and risking structural damage.
An aircraft landing in a lower-gravity region will have less weight on its wheels, slightly reducing the maximum braking force available from the wheelbrakes (which might well cancel out the landing-weight advantage mentioned in the previous bulletpoint), and, thus, requiring a slightly longer runway.

Do aircraft performance figures and calculations include corrections for local and/or regional variations in the strength of gravity, or are these variations simply considered too small to bother accounting with?

1: This is by no means meant to be an exhaustive list.


texts: Which commercial aircraft can perform a parallel engine start?

texts:
In various Youtube videos, e.g. this one, one can see that the Boeing 787 is capable of a parallel engine start (both engines are started at the same time). Are there any other commercial aircraft around that allow for a dual (or multiple parallel) engine startup?

What is the reason the Boeing 787 can perform parallel engine starts? What is the difference with other aircraft that cannot perform a parallel startup?


texts: How does a US registered pilot obtain approval to fly to Cuba?

texts: Because of US foreign policy, flights between the US and Cuba are prohibited except for certain conditions.  If I am flying there for an approved reason (such as to visit immediate family), how do I obtain the proper permission to do so?


texts: Why isn't KTEX's runway designation 10/28 instead of 9/27?

texts: Why is the marking on the runway written as (9/27) Telluride (KTEX), Colorado, USA. whereas the direction is 284 degrees? Shouldn't it be (10/28) instead?


texts:
From this page about nuclear bombers:

It seems out of Wild Wild West. What is this (Russian?) aircraft from another era? and what has been its use?

Update:We know now the image has been created using CG software, based on a real aircraft, that seems interesting and is by itself quite a mystery and technical feat that deserve explanations.
Why this design? gondolas, size, holes in wings, angular panels...? for apparently not so many people on-board.
Images of actual aircraft are found in answers. Also this one:

Source.
Thanks to @user52723a and @RonBeyer for providing details.


texts: Radar Control; is it possible for ATC to instruct track instead of heading?

texts: Is it possible to use the track instead of headings in the aim to apply a radar separation?


texts: Does it make sense to say an aircraft has an attitude of 3° or that it has a flight position of 3°?

texts:
I am trying to translate an aircraft manual, and there is a diagram showing what the HUD would look like given a "posición de vuelo de 3°".

The diagram is captioned in Spanish as "vuelo horizontal a 3° de posición de vuelo".

I'm thinking  of two ways to translate this, but I think both do not completely make sense, and I think they don't make sense because the original is using terminology in an imprecise way.

If I translate it as "Level flight at 3° flight attitude", it seems off because attitude is a combination of both pitch and roll, so how could you have an attitude of 3°?

If I translate it as "Level flight at a flight position of 3°", then it seems even more off because flight position, as I understand it, is combination of all 3 angles of orientation, yaw, pitch and roll. So you can't just say "my flight position is 3°"

So I am basically writing to confirm my suspicion that this doesn't really make sense and that the diagram is more likely referring to an elevation/pitch of 3° (with respect to the fuselage reference line). If anyone knows Spanish and is familiar with the term "posición de vuelo", then that's a bonus :)


texts: What are typical values of the lift-to-drag ratio for normal small aircraft?

texts:
Hi I am trying to do a rough estimation of forces acting on an aircraft wing and would like to know what kind of lift to drag ratio is normal. The exact profile hasn't been chosen yet, but the aircraft weighs less than 1800 kg and has a wingspan of around 13 m. The cruise speed is roughly 70 m/s.

As I understand, the maximum load factor to consider is 3.8, so the maximum lift is about 67,000 N; but how would I go about getting an estimate for the drag?


texts: What differentiates the entry procedures for spins and snap rolls?

texts:
Both a spin and a snap roll are aerobatic manoeuvres involving stalling one of an airplane's wings earlier and more deeply than the other.  Both are entered by pitching up sharply to stall the airplane, and applying a hard rudder input to yaw the airplane sideways and ensure that one wing stalls before the other, causing that wing to drop and the airplane to roll off to the side.  What happens next differs between the two:

In a spin, the increase in drag on the wing that stalls first causes the airplane to enter an extremely fast yaw (rotation about a vertical axis1) in the direction of said wing, keeping it more deeply stalled than the other wing; the high yaw rate centrifuges the airplane's mass away from the spin axis, preventing the airplane from rolling beyond the bank angle induced by the initial spin-entry yaw input.
In a snap roll, it's the decrease in lift on the first-to-stall wing which is important (rather than the increase in drag), causing the airplane to enter an extremely fast roll (rotation about the aircraft's longitudinal axis) into the first-stalled wing; unlike with a spin, the airplane's inherent directional stability prevents the initiating yaw input of a snap roll from producing any persistent yaw.

Thus, the same type of entry procedure can apparently result in two wildly different outcomes: a spin, with an extremely-high yaw rate but no significant roll rate, or a snap roll, with an extremely-high roll rate but no significant yaw rate.
How does one differentiate a spin-entry procedure from a snap-roll-entry procedure?  What determines whether the sudden pitch-up and hard rudder input produces a spin, or whether it generates a snap roll instead?

1: This axis usually is not coincident with the vertical axis of the airplane as a whole (that passing through the aircraft's center of mass), although it can be.


texts: Why don't we have allocated cabin baggage space just like seats?

texts:
There is always a hassle of finding overhead cabin baggage space. Why don't airlines, divide the space and allocate it for each seat, just like they have allocated space for cabin crew and demo stuff.

This way, each seat has their allocated cabin baggage space, so a passenger can board in peace knowing their cabin baggage space is reserved.


texts: How do pilots manage to remember ATC instructions?

texts:
Before takeoff, during flight, before landing and for taxiing, pilots are given several instructions by ATC.

Do they mentally remember all instructions? Or do they note them down somewhere such as in a notebook so that they do not forget?


texts: Should I record my helicopter and autogyro time in separate logbooks?

texts:
I have been flying autogyros for some years now, and I am out to do my license on UL helicopters.

I bought a new logbook to log all time in helicopters separately from autogyros. Is that correct?

In a few days I will also be taking some lessons in an R22. That's not even UL anymore. Do I have to get another logbook for all flying of non-UL aircraft? Would I log it all in the same logbook?


texts: What are the mechanical deflection angles for Airbus side-stick controllers?

texts: Does anyone know the angular deflection limits of the longitudinal (pitch) and lateral (roll) axis of Airbus's side-stick?


texts: What is the definition of "Sideline" in reference to aircraft noise?

texts:
The FAA has measured external aircraft noise levels and published the results in the Advisory Circular:

AC 36-1H - Noise Levels for U.S. Certificated and Foreign Aircraft

In the appendices, noise levels are listed for Takeoff (TO), Sideline (SL) and Approach (AP).

I understand the concept of Takeoff and Approach, but what is "Sideline"?   It is not defined in the document, nor does it show up in a search of the  Code of Federal Regulations.


texts: How does a pilot maintain stability for an unbalance loaded airplane?

texts:
Consider Cessna 172 which has 4 seats, including the pilot, with the seat configuration as the picture below. Say the airplane has no passenger, only the pilot him/her self. I am not sure where it center gravity (CG). For longitudinal (roll), probably we can consider it separate between left and right seats. But for pitch, I don't have any idea.

My question is, if a pilot want to fly his/her airplane, how he/she assign stability control so the airplane will not has tendencies, either regarding the longitudinal (roll) or the pitch. What else control he/she needs to apply to make the airplane safely fly due to the unbalance load?


texts: Why does the main battery discharge with the alternator running?

texts:
In my cessna 172S, when engine running at any RPM, the current at the main battery is below zero, indicating that the alternator is not charging the battery or the battery discharges, but the standby battery indicates a current above zero and it is charged by the alternator.

How can this happen?


texts: When is the logo light on the tail turned on?

texts: I noticed sometimes aircraft taxi with the logo light illuminating their tail, while others have it off. So is turning on the tail light at the discretion of the pilot?


texts: Do special procedures exist for commercial pilots flying over Russia?

texts:
Since Russia, and in particular the Asian part of it, is huge, I was wondering if there are special procedures for commercial pilots to follow over Russia (in particular and specifically Siberia and other sparsely populated parts)? (Except that they use the metric system.)

Does Russia provide radar coverage and flight following services over its entire territory? As an example, do the use procedures like the North Atlantic Tracks, or do pilots implement their "own ATC" by stating position reports regularly, just like over some parts of Africa?

Or is flying over Russia comparable to flying over any other European / U.S. / ... country with continued ATC service?


texts: What is the purpose of the three small bumps on the switches for landing lights?

texts:
What is the purpose of the three small bumps on the switches for landing lights and what is the history behind it? You'll see a similar design on Boeing, Airbus, and other aircraft.

Here is a picture of a 777 overhead panel:


texts:
Usually, there are four lights at the sides of runways which show airplanes' altitude status:

four red lights: too low
two red, two white: appropriate altitude
four white lights: too high.

If two airplanes with two different altitudes approach, do they see different number of white and red lights? Or are the lights set for the closer airplane?


texts: Can ATC handle a flight as emergency although the pilots have not declared an emergency?

texts:
The preliminary report for the LNI610 crash shows how much distractive conversation there was between ATC and LIN610 at a time when the pilots clearly didn't have the aircraft under control – as evidenced by the FDR data – and should have talked to each other to diagnose the problem, rather than to ATC. This violates the principle "aviate - navigate - communicate".

While it clearly falls within the responsibility of the crew to declare an emergency, my question is posed from the point of view of air traffic control:

(from the preliminary report, p.1+2)

  At 23:21:53 UTC, the LNI610 SIC requested approval to the TE controller “to some holding point”. The TE controller asked the LNI610 the problem of the aircraft and the pilot responded “flight control problem”.

  At 23:24:51 UTC, the TE controller added “FLIGHT CONT TROB” text for LNI610
  target label on the controller radar system as reminder that the flight was
  experiencing flight control problem.

The preliminary report reveals how much dispensable talk there was between ATC and LNI610 in this crucial moments even after the flight was marked as experiencing flight control problems.

My question is:

Seeing that the flight was marked by ATC as "FLIGHT CONT TROB", could ATC have handled the situation differently, e.g. bothering them less or even handling the situation outright as PAN PAN (don't restrict navigation, reroute other traffic, avoid communication as much as possible) even though it was not declared as such by the crew ?

Or did they essentially have their hands tied, obliged to treat the flight as any other as long as no emergency is officially declared via either MAYDAY or PAN PAN ?

I very much welcome any answers, including from pilots or ATC controllers who are unfamiliar with this particular accident, but can share their work experience (how this is handled in practice) AND/OR point to specific rules (how this should be handled in theory).

FDR data (timestamps + pink vertical lines added by myself at 23:21:53 and 23:24:51 UTC corresponding to the ATC excerpts quoted above):


texts: Can wing sweep decrease total drag force at low-subsonic speeds?

texts:
From  experience everybody knows if you put your arm out of car window at high speed(150km/h), it's a lot easier to hold arm angled backward then hold arm straight out(prependicular to airlfow).So conclusion will be that drag force is reduced..
Can wing sweep in same manner reduce total drag force at speeds up to 250km/h?

Pulling angled "beam" with rope in water will be easier than if "beam" is prependicular to flow.Right beam has smaller lift force but also less total drag force.Is this correct?


texts: Can I log instrument flight time for currency purposes in an Advanced Aviation Training Device (AATD)?

texts:
Advisory Circular AC 61-136 which outlines the approval and limitations of flight training devices seems to contradict 14 CFR 61.57(c).

To what extent can I use an AATD for instrument currency? In addition, to what extent can an AATD be used toward and instrument proficiency check (IPC)?

Edit:

I have located this document from the FAA Office of Aviation Safety that clarifies that AATDs and BATDs are governed by FAR 61.4(c) and are authorized for specific purposes and can be used in the same manner at a Flight Training Device instead of a Aviation Training Device as long as they have an approve Letter of Agreement (LOA) from the administrator.

This leads me to believe that an AATD qualifies for FAR 61.57(c)(2) not FAR 61.57(c)(3).


texts:
When I started searching for Heading Bug (other bugs like altitude, speed bugs), I didn't get much clear idea about it. Usually this is displayed on Horizontal Situation Indicator display on the direction of wind (calculated based on wind direction, speed?). This heading bug can be selected to a value by pilots during flight.

What is the use of heading bug?
how heading bug is calculated?
what's the significance of heading bug?


texts: Is the turning motion of a banked airplane caused by true centripetal force?

texts:
Virtually every explanation I have read of the aerodynamics of a turning airplane ascribe the turning motion simply to centripetal force, without further comment.  I'm hoping someone can check my understandings and conclusions whether this is true or not.
As I understand it, centripetal force is defined as the net of the forces on an object that keep it on a circular path.  Put another way, it's the resultant of the force vectors on the object.  Further, centripetal force always acts in a direction orthogonal to the object's direction of motion.
Now, with a banked airplane, the horizontal component of lift, in and of itself, will simply create a lateral force that introduces sideslip. The heading of the airplane must be continuously changed in order to change the direction of that lateral force, and thereby change the force vector from a lateral one to a radial (centripetal) one. This is done independently with the addition of yaw, either coordinated via rudder input, or uncoordinated via weathervaning.
Assuming all this is correct (again please check me), is it mathematically correct to state that true centripetal force is created by the resultant of the force vectors here (the lateral forces adding sideslip and the rotational forces adding yaw)?
Thank you very much for your help.
(EDIT: Through the answers below, I understand now that my third paragraph above is incorrect.  The horizontal lift vector remains perpendicular to the direction of movement (relative wind), not the airplane's heading.  Therefore, while yaw is necessary to maintain coordinated flight, the rotational force vectors behind it are not addends in the centripetal force calculation.)


texts: Why is the NAV ADR 1 ECAM caution a NO GO as per the MEL on the A320?

texts: There isn't much more I can post about the question but in the MEL out of the 3 ADRs if ADR 1 fails on ground the MEL doesn't allow for a dispatch.


texts: How does radar receive Mode C information?

texts:
I know primary radar of ASR can determine only slant range, so by using Mode C transponder, ATC can know the altitude of aircraft.

And I found that if altimeter setting of radar is changed, displayed altitude also be changed.

So I guess that Mode C transponder can deliver only pressure information not altitude information. So Radar convert this pressure information to altitide information referring to radar altimiter setting. And it is not important what altimeter seeting pilot set.

Is it correct?


texts: Why does fuel vaporization in a carburetor cause a temperature decrease rather than a rise?

texts:
So I know the most "prominent" conditions of carburetor icing is anywhere from 20 to 70 °F with visible moisture. There is also a tendency to have icing in the carburetor in the venturi throat due to a drop in temperature due to fuel vaporization.

The problem I'm having is if fuel is vaporized, wouldn't that be increasing the temperature? I don't understand how the temperature would drop.


texts: Is there a comprehensive source for aircraft specification data for most of the aircraft in the world?

texts: I'm aware that I can look at the Wikipedia entry for an aircraft and discover specifications like the MTOW, length, cruise speed, etc. However, I was wondering whether there is a (preferably free) source of all this data combined for most aircraft. Does such a data source exist?


texts:
Take Afghanistan as a for instance; do governments (e.g. USAF/RAF) or NATO construct ATC towers?

I'd imagine so, at the air bases, in order to land/takeoff the vast amount of aircraft.

Who controls the sectors where missions are ongoing? How are the different countries' aircraft coordinated and kept apart?


texts: Are there design differences between propellers powered by air (wind-power) and propellers for aviation?

texts:
What is the difference of design between a propeller designed to be powered by the wind (i.e. those huge wind power turbine blades) and those designed to be used to propel a plane that are powered by an engine (i.e. a Cessna 172's props)?

(To be clear, I'm talking about one that is powered by the air vs one that powers through the air.)


texts: What are the scale effects of GA wing tip airfoils?

texts:
[ update: I am adopting an improved description provided by Peter Kämpf: "...only looking at the airfoils in isolation..." ]

The goal of this question is to determine if wing tip airfoil scale plays a significant part in stall characteristics for aileron control.

Lets assume we have a small Piper or Cessna aircraft with only a change in size from root to a tapered wing tip. There is no washin or washout at the tip. Lets further assume the wing tip has 50% chord to the root (if some other value is useful, feel free to use what is appropriate). If Reynolds number has any appreciable bearing on the result, lets use approx 50kt/mph as a ruff stall speed.

Q1) Will the wing tip stall at the same speed as the root (root vs tip), or is there an appreciable difference do to size & scale?

Q2) What would the stall characteristics be (root vs tip) if we scaled the tip chord 50% but did not change the thickness?

Illustration for reference, values are not exact.


texts: Does the Air Force (United States) help design their own planes?

texts: I know that companies such as Lockheed Martin and Boeing design and build planes for the US Air Force. However, when I was thinking about this, I realized the Air force has no part in designing the thousands of aircraft they own (or am I wrong). Does the Air force basically act as a consumer or do they help in the process of designing the jets? (I know there is a job of an aircraft mechanic but they act as maintenance people and don't design the jet.)


texts: Why can’t aircraft use GPS to generate the IAS, instead of using pitot tubes?

texts: I’m mostly asking after reading about Aeroperu Flight 603, which was caused by a piece of tape blocking the sensor. Is there any other way to gather IAS or is this the best way to do it?


texts: Are the A320's A and B electrical buses both energized all of the time during flight?

texts:
I'm a novice reading a quick study guide.

For electric power, I notice that the A320 has two buses: A and B.

Are they both energized all of the time during flight? If not, is there a way to switch between buses?

The power diagram with the two buses looks similar to the Apollo Command Module and maybe the Service Module.  I wonder if it was a borrowed idea.


texts: Is it possible to achieve torque equilibrium in order to fly?

texts: I am trying to create a tricopter which will be used for SLAM, but my main problem is that before starting to construct it I am not sure whether or not it will work at all. The problem is that I need a sensor to be rotating on an axis vertical to those of the rotors. Moreover that part will not be on top or below the drone but rotating around its "chassis axis"(blue line on second ppicture), because the sensor must not have anything blocking its view. Is it possible to achieve it? If yes what is the optimum placement of the motors and the moving sensor? Since English is not my native language I understand that some things may not make sense please feel free to ask me anything you don't understand.


texts: Is an aircraft's maximum landing weight really weight, or is it mass?

texts:
I'm calculating the lift of a Cessna 172 and I don't understand the numbers given for weight. The maximum landing weight is 2550 pounds which is nearly 1134kg. But does that mean 1134 Newtons (weight) or 1134 kilograms (mass)?

Since weight = mass x gravity, I think the weight of the C172 is in Newtons even though it's written using a unit of mass. Am I correct?


texts: Why is ISA Standard pressure 1013.2 not used for contour charts instead of QFF?

texts: I am confused because QFF being actual mean sea level pressure is subject to change why would we use it for mapping terrain? Does this mean the height of a given terrain changes with the change in QFF? Tried to look for an answer for this everywhere but I couldn’t find any. Can someone tell me what am I getting wrong?


texts: What is the total EXTRA lift produced using an 80 deg flap and distributed propulsion?

texts:
What is the total EXTRA lift produced using an 80 deg flap? ( 50 deg flap at 30 deg AOA ) and distributed propulsion.

Specs: Ultralight, stall speed 20mph, ROW of 12 x 15" props along entire wing span in DISTRIBUTED PROPULSION, max local AOA estimated at < 9 deg ), electric 25 hp (total), MTOW 500 lbs, low wing in ground effect, max 3 ft height for xSTOL/nVTOL, VG's, full span single slotted flaps with spoilers , Clmax: 3.4.

Hypothesis:

A low wing ultralight accelerates with a short field takeoff, along a runway to 20mph and rotates to 30 deg AoA just prior to takeoff, producing the following:

Total lift = Wing lift (bernoulli/momentum/vortex lift + deflection lift )  + Prop lift + Flap Lift

Example:

Wing lift:

standard wing lift formulas, lift equal to airplane weight of 500 lbs.

Prop lift:

Estimated thrust at 20mph: 5lbs/Hp thrust x 25 HP = 125lbs thrust.

Prop lift = 125 lbs x sin ( radians(30 deg))= 62 lbs

80 deg Flap Lift

Thrust due to Prop wash on bottom of wing hitting flap
= 30%(???) of total thrust = 37 lbs.

Total extra vertical thrust/lift

= 62 + 37 = approx 100 lbs ( 20% extra vertical thrust/lift...!!!! )

Reduced MTOW wing requirements at Vtakeoff to Vflap

orginal MTOW = 500 lbs.

MTOW revised= MTOW original - extra vertical lift = 500lbs - 100 lbs.= 400 lbs.

This is the reason for asking the question:

Could I then resize my wings based on 400 lbs MTOW at Vtakeoff(Vso) to Vf, not 500 lbs?

Is this correct thinking?

See black tuft dwg below showing downwards air flow.


texts: What fraction of air intake becomes bleed air in airliner engines?

texts:
Gas turbines typically bleed air from the late compressor stages. Some of this air bypasses the combustion chamber and is expanded through the turbine to prevent the blades from becoming too hot. I believe bleed air is also used to provide hydraulic control of the control systems and also for utilities such as air conditioning and electricity generation.

I am interested to know just how much of the air intake to the gas turbine compressor becomes bleed air. I'm also interested in knowing how much of this bleed air goes to each application e.g. Utilities vs. turbine cooling vs. hydraulic control.

I suspect it varies a fair bit so I am mostly interested in how this occurs on larger airliners that would typically fly long international flights.


texts: What is the advantage of the blisk design in the new Trent XWB engine?

texts: What advantage does the "blisk" or "bladed disk" type rotor have over the usual rotor system?


texts: Is it normal for airport to transmit unmodulated carrier on its ATIS frequency for extended periods of time?

texts:
So I'm around 4 km away from the City-Airport Mannheim (EDFM/MHG). Various websites tell me that its ATIS frequency is 136.550 MHz.

When I tune to 136.550 with my VHF AM receiver, I can see a strong carrier, with no modulation at all. I've listened to it for several hours, on different weekdays and during different times of day.

So my question is: Is this usual behavior or not? I'm aware that the airport in question doesn't see much traffic, but I'd sort of expect the ATIS to be either running, when needed, or switched-off, when not needed.


texts: How do pilots estimate glideslope visually without PAPIs?

texts:
If my (enthusiast-level) understanding is correct, on instrument approach there are specific glideslope paths a plane is expected to follow. On ILS this is self-evident, but (again, if I read approach plates correctly), VOR DME approaches also entail a certain altitude that must be crossed at given DME distances. I assume, crews estimate their rate of descent based on their ground speed etc.

Now, when visually, apart from PAPI lights, is there any other way of estimating the correct glideslope? With C172s and 55 knots, I expect it's easier to simply crawl to the runway and adjust accordingly. But how does it work when you have a B737 or A320 landing on a 6000ft/1800mt runway without PAPI lights? I expect a certain kind of precision is required, but does it come merely with experience, or is there some other way?


texts: What does the "Caution" box mean on the sectional near Half Moon Bay, California?

texts: What does this Caution box on the sectional chart near Half Moon Bay, California mean? Is there an official reference for the meaning of this box?


texts: In the B737NG, is the CTR tank fuel the first to be pumped when there is fuel in all tanks?

texts:
In a B737NG, assuming you have fuel in all tanks, Wings and Center, and that all pump switches are ON, will the fuel from the CTR tank be the first to be pumped, despite all Fuel pump switches being in the ON position?
Will this happen even if the CTR fuel pumps are OFF and only the Wing Fuel pumps are ON?
And why are there so many warning in the FCOM about pumping the CTR tanks and warnings about not doing so in climb or descent if under 1000 lbs of fuel in the tank?
I have already read the "Why are fuel tanks in the wings filled first, and why are they used last?" post and answers.


texts:
Since speed is related to dynamic pressure, then why is static pressure used instead of dynamic pressure in ASI to measure speed?

Why is dynamic (or pitot) pressure not sufficient?


texts: We can see the effect of the tailwind on the plane's flight direction on the modern military fighter jet huds. I wonder about how can the avionic systems detect tailwind and which sensors using in the process.


texts: What's the purpose of this red marking on the fuselage of a Boeing 737?

texts:
I was watching some aircraft today and noticed a red marking on two of them.

What is that? I've seen that marking on many other aircraft.


texts: What is the standard procedure in case of inconsistent sensor readings?

texts:
After reading the answers I now know there are three independent sensors. I will leave the question as-is, to not take the answers out of context:

I do remember reading that airliners have two independent sensors and channels to deliver readings like airspeed and altitude to the cockpit (pitot-static system).
  If this is not the case my question will not make sense.

If the two systems show conflicting information, what is the standard procedure? If one of them is 'overspeed' or close to stall speed should the pilots assume this is the one to focus on? Or do the pilots reason based on each situation independently and all the other factors at play?


texts: Are there any situations where having high lift but low lift to drag ratio would be beneficial?

texts:
From my understanding, high lift to drag ratio could make an aircraft efficient during cruising conditions. This is when the aircraft is in equilibrium, lift is equal to weight, and thrust is equal to drag, and since there's less drag, less thrust is required. Is this correct and are there situations where having higher lift but higher drag as a consequence would be beneficial (e.g. higher camber has higher lift, but drag increases more leading to a lower lift to drag ratio)?
For example, if lift generated were to be around 10000N with 700N of drag (14.29 l/d) compared to less lift and drag, 8000N of lift with 600N of drag (13.33 l/d), would less drag at the expense of less lift be worth it in the context of cruising conditions (where thrust would need to equal drag to maintain constant velocity)?
Sidenote: I'm mainly thinking about this in terms of cruising conditions, not necessarily during climb or descent, but if you're happy to share any info on that, I would appreciate it too!
EDIT: Just to clarify (thanks for the comment quiet flyer), this is lift and drag generated by the wings.


texts: What is the maximal altitude at which an emergency slide can be deployed?

texts:
If I understand correctly, the mechanism to inflate an emergency slide relies on a tank of inert gas and on an "aspirator" that sucks ambient air. This aspirator works thanks to depression causes by the stored inert gas velocity (Venturi effect) while it inflate the slide.
This implies that the slide requires enough outside air to inflate correctly. I'm confident such mechanism are certified to work at high altitude international airport (I'm thinking of Lima but there may be other international airport at high altitude), but an aircraft can still crash in high altitude mountains, higher than any airport.
I wonder what is the minimal outside pressure required to inflate an emergency slide. Maybe air density is more relevant than pressure. Given the standard atmosphere model, both can be converted in altitude (either using pressure-altitude or density-altitude).
What is the maximal altitude at which the mechanism to inflate an emergency slide can work as expected (i.e. suck enough outside air to inflate the slide)?


texts: How much does pilot technique affect brake life?

texts:
Anecdotally I have heard of various things that I can do to make steel brakes last longer before they have to be replaced, and they make sense but how much does it really help?

Things that I have heard:

Land at the minimum recommend speed
Use maximum reverse thrust (if you have it)
Delay braking after landing (if on a sufficiently long runway) to allow slowing before brake application
Various taxi techniques (taxi on one engine, don't ride the brakes, but instead build up speed and then brake to slow down.  Rinse and repeat.)

Are there any studies that have been done to show how much these things help and whether or not it makes a measurable difference?


texts: Does navigation database provided by the database providers like Aeronavdata or Jeppesen consists of company routes?

texts:
Does navigation database provided by the database providers like Aeronavdata or Jeppesen etc consists of company routes .

How is the company routes maintained are those modifiable by the OEMs ?
Is navigation database customizable ?

Any insight on this will be helpful.


texts: How often, and how promptly, do airports have to renumber runways because of magnetic pole drift?

texts:
This question was prompted by this answer to another question by Jamiec.

As the magnetic poles drift (usually pretty unpredictably), runway numbers become inaccurate. As noted in the linked answer, this has resulted at the very least in the renaming of the 15/33 runways at Madrid to 14/32.

How often does this happen, and at what point is it no longer reasonable for pilots to make the corrections necessary to make a smooth landing, requiring a renaming of the runways?


texts: Is it possible to reuse water extracted from the PACKs Water extractors?

texts:
During the Process inside of the Air Generation Unit (AGU) there is a water extractor behind the condenser separating the water from the air which will flow to the Re-Heater.

Is it posible to filter this water and re-use it for lavatory flush or hand wash water?

Since Humidity at FL300 is around 3%, is there even sufficient water being extracted to refill the tanks?


texts: What is the purpose of aileron droop used in some commercial airliners?

texts:
As we know ailerons aid the aircraft to make roll movements and provide lateral stability.

But, what is the intent behind drooping them in some flight conditions, especially when deploying flaps?


texts: What makes the left engine on a conventional twin-engine aircraft the critical one?

texts: I already know that this is because of P-factor. But I don't know how to draw a picture or explain this simply?


texts: How is the bandwidth of an actuator selected for a primary flight control surface?

texts: How the bandwidth of an actuator is selected for a primary flight control surface? Is there any standard? Based on what factors this decision is made?


texts:
Is there a distinction between a cockpit and a flight deck on an aircraft, or are the terms interchangeable?

Boeing refers to the flight deck The new Flight-Deck Displays and Airbus refers to the cockpit Passenger Aircraft>Cockpits

Based on this image,

would the B-2 be described as having a cockpit or a flight deck, or is there not enough information in this image?


texts: Is it possible to use US-made engines in Russian made air-frames?

texts:
Suppose, someone buys 300 Pratt & Whitney engines from the USA and 150 Mig-35 air frames from Russia. Then, they use their in-house expertise to fit those engines to those air-frames.
What challenges would have to be faced by the user?


texts: Why does the Antonov 225 needs 6 crew members?

texts: Why does the Antonov 225 need 6 flight deck crew? What are they called and what do they do?


texts: Why could a Rotax 914 light aircraft lose power at 7000 feet?

texts:
I was flying an RV 4 equipped with Rotax 914 engine and variable pitch propeller.
The problem was observed during flight above 7000 feet; vertical speed became 0, RPM overshoot for 2, 3 seconds to 6300 when the turbo engaged for gaining height. I did make an effort for turbo but was not gaining height. It felt like under power, but take off was normal. Air Box target pressure was normal. All other engine parameters  also normal. So I came back to pavilion.

Could you please suggest possible causes?


texts: If, one day, we have an electric airplane, will it be easier to control than a fuelled airplane?

texts:
Elon Musk said that Tesla will make battery which can last for million miles.  So probably in the next few years there will be a (small) airplane powered by an electric motor rather than by fuel.

If this happens, will controlling the electric airplane be easier?  The CG won't shift as fuel is consumed.  But the constant battery weight probably will problem to the maximum landing.


texts: what is the difference between max nose wheel steering angle and effective steering angle?

texts: I am looking at a diagram. The max nose wheel steering angle is 72 deg and effective steering angle is 66.1. My question is now why do we not have just one nose wheel steering angle? what is the difference between max nose wheel steering angle and effective steering angle ? And what angle is used for which cases?


texts: Why aren't passengers trained and evaluated for operating emergency exits in commercial aircraft?

texts:
The passengers sitting on the overwing exit doors are expected to operate the doors in times of emergency, with only a verbal instruction. Is that enough?
Q. Why can't we have a designated area in the airport where a setup of emergency doors are kept and the passengers are trained and evaluated there before being alloted the seats on the emergency row. It can be short 2 min course, where passenger actually opens the door and puts it aside.

There have been instances which highlight that proper training is required for passengers Soource:

Passengers will frequently open an exit as soon as evacuation begins which may result in them evacuating into danger. This occurred in the Ryanair engine fire in Stansted Airport in 2002, where passengers evacuated themselves onto a burning wing, despite airport fire services personnel shouting at them to return inside the aircraft and evacuate via a usable exit. Source

Another hazard in the use of overwing exits is them being improperly opened (usually a result of passengers in these seats not paying attention to the verbal briefing provided pre-departure, or not observing the opening instructions on the safety card and on the exit). The majority of overwing exits involve the passenger physically removing the hatch from its frame and disposing of it outside on the wing without blocking the exit. Research conducted at the Cranfield Institute in the UK Source

Above situations taken from Wikipedia
https://en.wikipedia.org/wiki/Overwing_exits#Hazards


texts: How is an A320 on the ground kept cool inside if the APU fails?

texts:
What happens to the air conditioner when the APU is not available due to damage or it just fails?
Also adding that the airport does not have an air conditioning unit. Since it is above average sea level, what procedures should be performed?


texts: How do pattern and overflight altitudes work for airports underneath Class C airspace?

texts:
Lowell City Airport (24C) has an elevation of 700 feet MSL. So normally, the pattern altitude is going to be 1,700 feet, and the altitude for overflying the pattern is going to be 2,200 feet.

However, 24C Lowell is located underneath Class C airspace which starts at 2,000 MSL, so you can't fly at 2,200 without talking to Grand Rapids.

What should I do if I'd like to fly over the field? I can think of a few options:

Maybe 24C Lowell has a non-standard pattern altitude, like 1,400, which would allow me to overfly at 1,900. (How could I find this out using official sources?)
Split the difference between pattern altitude and the Class C. If the pattern altitude is 1,700 and the Class C starts at 2,000, maybe I can overfly at 1,900.
Establish communications with Grand Rapids Approach, then go ahead and overfly at 2,200 while monitoring both Approach and CTAF at the same time.
Just avoid overflying the pattern, and fly around it instead.

When in doubt, I'm going with option 4. But what should I know about the other options?

I do have some particular questions about option 3. If I do choose to contact Grand Rapids Approach and climb to 2,200 to overfly, then I'll have to monitor both Approach and CTAF at the same time, right? Can most small airplanes even do that?


texts: What does runaway failure mean (position difference between APPU and FPPU) on A320?

texts: I've been reading the description and operation of Flap systems. WTBs will stop and hold the transmission whenever SFCCs receive some failures.


texts: How does a pilot replace their logbook if it has been lost?

texts: I got my private pilot license when I was 17 but was unable to continue flying. I am moving into a position to get back in the air, but I no longer have my log book as it was lost between moves. What is the best way to move forward?


texts: How do you enter the hold after a missed approach at Riohacha (SKRH)?

texts:
I have a question regarding this Missed Approach Procedure

Im in my final approach segment and reach DME 1.1 and the runway is not in sight so I start my Missed approach, how should it be executed?

Since I have to hold I'd start a tear drop entry turning to heading 125° and then left turn intercepting 275° course inbound. This option sounds viable to me
I first do a right 360° as charted (???) and going to the VOR and then starting probably a parallel entry into the hold. This doesn't sound viable to me

Textual description is also clear about that 360°
If it 1.) why would they chart that 360° there?


texts: Piloting as a perishable skill - what skills go first and how to self-assess and mitigate skill loss?

texts:
I know that in accident reports they will typically say the total number of hours the pilot had, but also the total hours in type and total hours in the last 90 days.  I know from personal experience that landing an airplane can be a perishable skill (I recently went 60+ days since flying and my landings were not the picture-perfect examples they usually are...don't get me wrong, nothing unsafe, just wasn't proud of them...drifting off centerline, excessive float, etc :)

The FAA seems to know this with the 90-day passenger carrying requirement (3 take-offs and landings within 90 days to carry passengers during the day and 3 to a full-stop for night passenger carriage).

All this to say flying doesn't seem to be "just like riding a bike - you never forget it."  But in what sense?  The muscle memory goes? The "seat of the pants" sensation starts to feel foreign?  I know charts can change, regs can change, but do you really "forget how to fly," or just "lose the touch?"

What skills go first, and what is the best way to self-assess your skill quality and mitigate the loss of it?


texts: Is there a general standard for servo actuators?

texts: It is said in the standard AS94900 that the standard ARP490 should be considered for the actuators of the control surfaces in the aircraft. However, this standard is on servo valves and not servo actuators. is there a specific standard for servo actuators in aviation? or the servo valve of the servo actuator should be tested separately?


texts: Who decided which airspaces not to fly through and how?

texts:
I was looking at some flight paths, and I noticed that while some airspaces are ignored by planes for "obvious" reasons, like the Ukraine - Russian border airspace.

For example, this flight seems to purposely ignore the Ukraine airspace.

But on the other hand, I found some flight which are not ignoring airspaces which should probably be ignored. Like planes flying over Syrian airspace or over Yemen. These places too are war zones and might have militant groups capable of repeating something like MH-17.

This made me wonder as to who decides what airspaces to not fly over, and what are the criteria to do so?


texts: How do you calculate minimum runway lengths for Part 135 operations using the 60% rule?

texts:
FAR 135.385 requires that at your destination airport your flight planning shows that you could make a full-stop landing "within 60 percent of the effective length" of the runway when flying transport-category turbine-powered aircraft.

For piston-powered aircraft FAR 135.377 has a similar 70% rule.

How do you calculate minimum runway lengths under these rules?
Can you use 80% of the runway? What if the runway is wet?


texts: Is the capacity of an airspace sector related to the number of routes it crosses?

texts: I've been searching for data about the capacity of sectors for my PhD research but somehow can't find any...the only thing I found is the routes it crosses ....can we conclude that it's the capacity or there is another factors involved. I would appreciate any help


texts: What is this aircraft that has flown over my house all day?

texts: I mainly joined to ask this question. I would not have been so curious had it not flown directly over my house at least 5 times in about a half-hour. Every time my house started rumbling, I’d rush outside to snap some pictures before it was too far gone. Any help would be appreciated - especially if anyone knows why it came across so frequently.