texts: Which country started the tradition of naming aircraft?

texts: I'm doing a project on the Enola Gay and I wondered which country started the tradition of naming aircraft?


texts: Some aircraft are equiped with auto landing to assist on zero visibility and ceiling land. Actually, how does this system work?


texts: What happens to manifold pressure reading following a reduction in both throttle and RPM?

texts:
This was one of the questions in my online ground school quiz (PPL), detail as follows:

To set climb power, you reduce the throttle (manifold pressure) and then the props (RPM lever). After setting the props you expect the manifold pressure to:

A) not change
B) temporarily rises than fall again to where it was
C) fall slightly
D) rise slightly

My original answer was there is no net change in the MP reading after performing those two reduction actions.

My understanding of MP reading is that a reduction in throttle would mean more suction/vacuum as a result so the MP reading would decrease. On the other hand a reduction in RPM would mean less suction/vacuum so the MP reading would increase.

Because of the above, and that there is no other detail from the question as to how much changes each action had, wouldn't it be correct to expect MP reading to first decrease (from the throttle reduction) and then rises back again (from the RPM reduction). The net change therefore should be 0.

The correct answer however was d) slightly rises.
The explanation that was given is because the airplane was transitioning from take off power to climb power.

Why does MP rises slightly in this case?


texts: Could a pick up truck save a plane with failed landing gear?

texts:
I recently saw this fictionalized video.

While it's not real, I do wonder if this could be possible, even if not the best way to handle the situation.


texts: Is there a way I can find out online what private jets are parked tonight at a nearby international airport?

texts:
There is an international airport about 10 miles from my home.
Is there any way I can find out online what private jets are parked there tonight? I am not familiar with any of the lingo used here :) so if you could respond in layman's terms I'd greatly appreciate it.


texts: Autothrottle's control target during autoland

texts: I read some pilots manual which indicates that the AT retard mode will be active at 30feet AGL to retract the throttle to idle, but the flare mode starts from 50 feet AGL? Should the throttle to be retracted to idle before flare? If not what is auto throttle doing during the flare maneuver, try to maintain the speed?


texts: Besides Line up conditional clearance in a PREPARATION FOR TAKE-OFF situation, where else can we use conditional clearance (on an apron, taxiway, etc.)?


texts: Why is there still a preference for turboprop airliners over the new regional jets?

texts:
In the 1950s and in the early 1960s, jets were mostly available as fighter/military or big, long haul aircraft. Regional aviation was based primarily on piston aircraft that could operate in smaller airports.
When planes like the Boeing 727 and 737, Douglas DC-9 and Hawker Siddeley Trident came out, they finally brought the jet era to the regional aviation. But still, they were loud and inefficient. That's where the turboprops come in: they perform better than pistons and are suitable for small airports; they don't go as fast as jets, but are usually cheaper to maintain.

Given all that, most regional airlines started to use turboprops for their city links.

In the recent years, however, jet engines are getting quieter, more efficient and powerful. Embraer's Regional Jets and E-jets are out there; more recently, we've seen Bombardier releasing their CSeries and Embraer selling the first E2 units. Even though these planes are highly efficient, fast and suitable for short runways, airlines from countries like Brazil, Indonesia and India are still using turboprops as almost the entirety of their regional fleets. The development of modern planes like the ATR72-600 and the Bombardier Q400 shows how high the interest from airlines is.

The question is, what could be the cause of such preference? Why don't airlines prefer regional jets over turboprops, given their efficiency and speed and considering the tendency people have to "fear" propeller planes as old and untrustworthy?

Speaking of numbers, what would be financially better for a company: flying an ATR/Dash 8 or a modern jet like the E2/CSeries?


texts: What is this plane doing flying back and forth near Sydney at night?

texts:
As I write this, a mystery plane is going back and forth over south Sydney, Australia:

The plane took of at Bankstown, flies straight from West to East and back, with a distance between paths of about 600m. It maintains a steady height of ca. 4100ft at a speed 120kts.

It is a Cessna 404, but flightradar24 provides no call sign or any other ID.

I noticed the plane ca. 00:30 on 10 May 2018, as it was at its 8th "lap", and took the above screen shot. It may have gone on for a while, perhaps for an hour or more.

As it's night, no markings on the plane are visible. It has the usual white flashers on the wing tips and the top of the rudder, and the red and green marker lights. The plane is quiet loud (prop), but that's most likely only because it's night and there's no other sound sources in my suburb.

Does anyone have an idea what that plane could be, and what the purpose of such flights could be? Obviously, they (whoever they may be) waited until after the curfew of Kingsford Smith (23:00) to not get in the way of commercial traffic.

Might be similar to this question, but I have no way of knowing whether it is the same. Italy and Australia are different countries. E.g., to my knowledge, Europe doesn't permit Police planes or helicopters above urban areas without reason. Australia does.


texts: What aircraft are parked in this naval air station?

texts:
In May 2020 I saw C-130 Herculess on a naval air station in Ventura County, California. Later, I decided to use Apple Maps so that I will remember what I have seen.
Apple Maps showed some C-130 Herculess, F-18 Hornets, P-3 Orions, and a few other aircraft. But when I zoomed into one of the air stations, I noticed some strange aircraft parked next to the P-3 Orions. They appear to be either a foreign aircraft, or some kind of experimental aircraft that I do not know.

Six of the unknown aircraft have a large swept wing, while two others have a delta wing featuring what looks like a canard.


texts: Listening to APP for several major (US class B) airports, it seems that every flight is vectored to intercept the localizer.  Is it really possible that 100% of flights filed an ILS approach?  If so, why?  It seems like at least some (perhaps small) fraction would have filed an RNAV approach.  Can someone with only GPS still "intercept the localizer" by flying the given vector until the runway is in sight and then get cleared for visual approach, so actual ILS doesn't matter?  Or does that case just never come up because ATC knows (via the equipment code in the flight plan) who has ILS equipment available and makes them use it even if that's not what they filed?


texts: Was it ever possible to land big commercial jets from the missed approach point during non-precision approach?

texts:
When you shoot a non-precision approach, you are expected to maintain the MDA until the missed approach point, and if you have the runway in sight before you get there, you may proceed to land on the runway, and if not, you must perform a missed approach.

My question is: Was it ever possible to land big commercial jets when the pilots spotted the runway right at the missed approach point during non-precision approach?

With the benefit of Visual Descent Point (VDP) and Constant Descent Final Approach (CDFA), most airline pilots today do not need to worry about this, but I'm still curious: Was it possible?

To add, the reason why I'm asking this question is that if a stabilized landing was not possible in some airplanes (big commercial jets), why was and still is the missed approach designated far too close to the runways for stabilized approach on most non-precision approach charts, instead of it simply being designated at the VDP point, when after all it's a "missed approach point"?


texts: How did Wilbur Wright create and use the formulas he mentions in his letter to Octave Chanute?

texts:
In a letter written by Wilbur Wright and addressed to Octave Chanute, dated 1903/06/18, I have found two things that I do not quite understand.

  Our engine develops at the brake 15.6 horse power and we are convinced that this is very close to what we will be able to reach as a maximum. It furnishes in foot pounds at the brake, energy equivalent to 23 percent of the heat units
  contained in the fuel, so its efficiency is some twenty percent higher than the usual efficiency of gasoline engines which ranges from 14 to 18 percent of the total power contained in the fuel.

How did the two brothers make such a revolutionary improvement?
Modern gasoline engines have a maximum thermal efficiency of about 25% to 30%. The Wright brother's motor had an efficiency of 23% in 1903.

  The Dumont motor may develop more than 10 horsepower but it is with me a case of seeing before believing. The screw of the airship was 4 meters in diameter and had a pitch of 4 meters, and the engine at 1200 revolutions (which is the speed of maximum power of motors of this size) drove it 200 turns per minute and gave a thrust of 154 to 165 lbs. Now if you multiply the thrust, by the pitch divided by the circumference of the screw, and multiply this by the travel per minute of the center of pressure (which is about 5/6 of the circumference of the screw) you will find that the result is about 10 horse power.”

It is evident that the Wrights used the relation:

Power = Thrust x (5/6) x pitch x (RPM/60 sec)

Where does this formula come from?

What exactly is that "center of pressure (which is about 5/6 of the circumference of the screw)"?


texts: Why are First/Business Class seats at the front of aircraft where it is the least safe?

texts:
According to this image, taken from The Science of Survivability (Page 79) from NOAA, the statistically safest seats to sit in are at the rear of the plane (69% survival rate vs 49% at the front).

From a business perspective (and ignoring any ethical considerations of whether passengers should pay more for a better chance of survival), it would seem to me to make more sense to put your highest paying and likely most regular passengers in the safest part of the plane, the rear.
Yet almost exclusively they are placed in the front, the un-safest part.

So why are First/Business class seats in the un-safer front of the craft and not the safer rear?


texts: How do you calculate the lift coefficient of an airfoil at zero angle of attack?

texts:
Thin airfoil theory gives $C = C_o + 2\pi\alpha$,  where $C_o$ is the lift coefficient at $\alpha = 0$. However, I couldn't find any equation to calculate what $C_o$ is which must be some function of the airfoil shape. In other words how do you extend thin airfoil theory to cambered airfoils without having to use experimental data?

This is my own attempt, I made this airfoil model of the lift coefficient of the airfoil at zero angle of attack for a project I am working on. It's derived from a Joukowsky transform. it seems to work but how is $C_o$ actually calculated?

Because it is derived from the Joukowsky transform of the inviscid potential flow around a cylinder it's more accurate at high Reynolds numbers.


texts: Does the Lilium VTOL wings produces lift during takeoff?

texts:
I just had a look on some of the recent development in the personal VTOL electrical aircrafts.
I am wondering if the Lilium VTOL wings produces lift during takeoff?
I would expect a quit high wind speed moving over the wing generating negative pressure, hence, beside the thrust force generated by the fans additional lift is generated over the wings? Is this correct?


texts: How are sector capacity constraints set in the current US ATC system?

texts:
My understanding is that in ATC, one of the constraints when considering the distribution of flights is the number of aircraft occupying a sector. Each sector can have different capacities.

I have read many academic approaches on how to calculate these capacities, but my doubt is: what is the method used right now, on February the 6th 2017?


texts: Why does the elliptical wing have the lowest drag?

texts: I read that the elliptical wing has the lowest induced drag. Why is that so? I welcome a mathematical and intuitive explanation.


texts: What is the Fuel-Oxygen ratio for a large turbofan at cruise conditions?

texts:
What is the Fuel-Oxygen ratio (by mass) for a large turbofan at cruise conditions?

In order to be concrete, I'll just pick an engine at random. I pick the GE90-115B. Okay it's not really random, it's just the largest turbofan I know of.


texts: What does the ATC instruction "Make left traffic, runway 19L" mean?

texts:
I'm playing Prepar3D and when coming in for a landing I'm usually told something like Make left traffic, runway 19L. I'm not sure how to interpret this because I'm not a pilot.
Should I go to the left of 19L for my downwind leg so the runway is to my right, or should I go to the right, with the runway on my left?
Also with parallel runways should I go to the left of 19L exactly or is it the left of 1R? I'm very confused!


texts: Transonic buffet - reason for a rapid movements of the shockwave along the wing chord line?

texts:
I know that transonic aerodynamic buffet is caused by the separated turbulent boundary layer striking the airframe (horizontal stabilizer, wings, fuselage) with considerable force causing a high amplitude vibration, which physically shakes the whole aircraft. And during a buffet, a shockwave will be apparently moving back and forth just like in the video link I provided below:

Since the shockwave is usually stationary on the airfoil, then why it starts suddenly oscillating once we enter a buffet boundary? Any ideas?


texts: CL604/650 (or CRJ1/2) max loiter time (using it as a reference point to compare the A-10 to)

texts:
In some discussions I was having with a (back-office) USAF acquaintance about the F-35 vs. A-10 debate, the topic of loiter time came up.  Wikipedia provides a 1.88 hour (112min) loiter time for the A-10 at a 250nmi combat radius with what appears to be a CAS loadout and a 5000' loiter altitude.  However, I'm not sure how heavily that is influenced by altitude (obviously, being at 5000' doesn't help any jet's gas mileage) vs. how much of that is being influenced by being a very "dirty" airframe laden with draggy protuberances and external stores.
So, given that the CL601/604/650 and CRJ100/200 have a similar MTOW and basically identical engines to the A-10 on a relatively "clean" airframe, assuming you had some reason to send a laden CRJ boring circles over some spot 250 nmi away at 5000' for a while (maybe it's carrying some sort of scientific payload internally), and were limited to 11klbs of fuel in doing so, how long would that CRJ be able to loiter before the flight crew had to start turning back home?


texts: Which parts of an airplane are made of buoyant material?

texts:
Which parts of an airplane (to make this question more specific: accessible in the main fuselage where the passengers are aboard) are made of buoyant material.
Imagine a plane is about to crash into the sea, you might wanna hang on to something that could keep you afloat, so here’s a few things that I think are buoyant(based on the floating debris seen after a crash):

The life vest/jackets which we can inflate
Seats
The doors(the ones through which we enter or any other door)

Which things would someone want to hold onto, to increase chances of survival?


texts: What are the differences between C208 versions?

texts:
I am aware of a few versions of C208:

C208 Caravan
C208 Grand Caravan
C208 Grand Caravan Amphibian

Amphibian has pantoons with retractable landing gears, but what is the difference between C208 Caravan and C208 Grand Caravan? Is it just the cargo compartment in the belly? Are there other versions of C208? What are the differences between them?


texts: Was the speed trim system on the B737 Classic modified to counter increased thrust?

texts: How much additional thrust did the 737 classic generate compared to the original 737? Was the speed trim system added to counter the additional thrust?


texts: What parameters to focus on when constructing a wing for turning?

texts:
I want to construct a flying wing (glider) with the sole purpose of performing a helical turn (or a circular turn with no propulsion attached) with somewhat of a fixed radius. What should be the main parameters of the flying wing that I should focus on?

Thanks


texts: What PPL routes are available with gliding experience?

texts:
I'm an early solo glider pilot, with the long term goal of also obtaining a PPL (not a LAPL(A)).  I am planning to do this after I have obtained at least my bronze badge, which I aspire to within the next twelve months.

Originally I thought that the only route open to me was to do the full PPL.  My understanding was that I can get a credit of 10% of P1 hours on a glider deducted from the requirements (max 10 hrs), however the CAA website refers to holders of "a pilot’s licence for another type of aircraft, except balloons".  I'm not sure if that applies to a bronze holder or if I would need to obtain a LAPL(S) or SPL for them to count (for which I would presumably need a bronze XC endorsement to make the required XC flight).

If I obtain a LAPL(S), then according to the CAA I can add a TMG rating (6+ hrs) and then, after hours building (24hrs) do a conversion course (15+ hrs) to the full PPL(A).  It's not clear if this route is available if I obtained an SPL, although for a fee I believe you can swap licences.

Can P1 hours as a glider pilot count towards a PPL(A) without obtaining a LAPL(S)/SPL?

Is the LAPL(S) -> TMG -> PPL route viable? Would I need to go to an "ATO" for TMG training or can my local gliding club do this?

Aside from just doing a PPL from scratch, are there any other viable routes that I've missed (e.g. via a LAPL(A) on a TMG somehow)?


texts: Why do most GA aircraft not have vortex generators?

texts: It is my understanding that vortex generators produce more favorable aerodynamics by delaying flow separation. If this is the case, why do more GA aircraft not have vortex generators?


texts:
Compared to a [modern] turbofan/turbojet, why is the throttle response slow in a turboprop?

A constant speed propeller mounted on a piston engine responds much quicker.

Is the underlying reason mechanical (e.g. size of combustion chamber), or electronic (e.g. ITT protection)?


texts:
I'm studying for my PPL and I've accumulated roughly 70 hours towards my PPL and am only now doing my cross country training.  Sometimes life gets in the way.

I am a fan of my CFI but had a situation this past weekend that has made me a bit uncomfortable - he fell asleep on 3 occasions during my first cross-country.  Is this a sign of a bad CFI?  Is it something to be concerned about?

I'm also wondering - is it important to know what you're going to be expected to work on before each lesson and we figure out what we're doing for the lesson during preflight?  Right now most of the agenda is being driven by me and I'm wondering if that's normal.

What's a good/bad CFI?


texts: Are there certification requirements for an emergency descent?

texts: In case of emergency, an aircraft may have to descend very quickly. Is there some performance (L/D ratio with full spoilers, descent rate, ...) to be proven in the certification process for such descent?


texts: NACA airfoils are not used anymore except on some aircraft. So which type of airfoil does the 737 use? Which company designs it and builds it?


texts: How does cabin pressure vary with respect to ambient pressure during descent?

texts:
I came across this statement in a book -
"During a descent, the cabin pressure in a pressurized aircraft usually climbs at as lesser rate than ambient pressure".

Could someone explain this statement in simple words?


texts: Alphanumeric flight identification in flight plan

texts:
Why do some airlines use alphanumeric callsigns in the flightplan when the flight number printed on the ticket consists of only numbers?

For example, the flight TK871 uses callsign THY4JT.


texts: What are the 2 protrusions next to the fore ground lights on the Tu-22M3?

texts:
Here's a reference image :

What are those 2 spokes coming out next to the ground lights ?


texts:
I am thinking of getting my pilot license, I would love to fly a helicopter or a small plane, but I don't know where to start. What do I need to get a pilot's license?

Things like:

How much does it cost
Get a cheap plane or chopper
Where to take lessons
Theory and practical
Is there a difference which plane or helicopter I may fly, especially in size

Any info is welcome.


texts: Will a quad fan arrangement on an aircraft help with pitching moments during VTOL flight transition?

texts:
The phenomena of ducted fan assemblies inducing pitching moments whilst in transition from vertical to horizontal flight paths is a problem I have seen mentioned by many designers and engineers of VTOL aircraft. I am wondering if the quadratic arrangement(a fan placed at each of the outermost corners of the aircraft) would help alleviate these issues. It would seem to make sense as the front and rear fan pitching moments about a central CG would cancel each other out, though still causing stresses on the airframe.
Are these pitching moments still a problem in quad fan configurations, and has any research been done into the inlets of ducted fans to stop these pitching moments?


texts: How much more economical are planes with retractable gears vs. those with fixed gears?

texts: Many small planes have fixed gears, some have retractable gears. All things being equal, the plane with retractable gears would have to be more expensive than fixed gears, as the mechanisms involved in retracting them is obviously more complicated than fixed gears. On the other hand, planes with fixed gears should have somewhat more drag than a similar plane with retractable gears when they're retracted. This would imply that a plane with retractable gears would consume less fuel than one with fixed gears. If the difference could be quantified, how much more economical would the plane with retractable gears be vs. one with fixed gears?


texts:
Is it legal to bring your own survival gear aboard an airliner?

Considering the sobering article by William Langewiesche that is appearing in the July 2019 edition of "The Atlantic", one might want to consider bringing:

Oxygen canister with regulator and pressure breathing mask
Parachute


texts: What causes harsh noise during TX/RX on VHF radio?

texts: I am running some trial radio test on PAE VHF main radio and during TX from ATC there is harsh noise at the background even though TX is 5/5. Likewise for the incoming RX from aircrafts. So I swapped the main radio with the standby radio but is giving me same results. I want to know what is causing this noise and how to eliminate it.


texts:
Did the twin engined Lazair ultralight have a throttle for each engine?

I know larger aircraft have dual throttles.

What about the smaller aircraft like ultralights?

It would be so much easier just to have a single throttle, much like a motorcycle throttle which splits into 2 on a 2 cylinder, 2 carb bike.


texts: Are CTAF and UNICOM frequencies routinely recorded?

texts: ATC communications are recorded for later examination by accident investigators or regulatory agencies. Are CTAF frequencies at untowered fields usually recorded? How about manned UNICOM frequencies?


texts: How do I determine the probable path of a future flight?

texts:
As a passenger on a regularly scheduled flight, how can I determine what areas my flight is likely to overfly?

I understand that inclement weather, other aircraft, and other outside influences (both somewhat predictable and completely unpredictable) can and will modify the planned route to some extent, which would be bonus information, but not necessary.


texts: Where does the final cooling take place in the air cycle machine of the air conditioning system?

texts: On aircraft with an ACM air conditioning, where does the final cooling take place? Is it in the ACM expansion turbine or in the ACM compressor?


texts: Why F4 Phantom II didn't have an cannon?

texts: Question is simple but seriously ? Who would design a FIGHTER bomber without an cannon ? What was the crazy reason they didn't added an cannon to it ? (Also My CPU is Athlon X2 II 250.... If only I had an Phantom CPU instead of an Athlon series...)


texts: Why hasn't there ever been a large 4-engine commercial airplane with 2 engines on the wings and 2 engines at the tail?

texts:
This question refers to large passenger jet aircraft only, which I define as being able to carry at least 100 people.

There have been many 2-, 3-, and 4-engined planes in this category. Some of the twinjets have both engines on the wings. Other twinjets have them both at the tail. Some trijets have all engines at the tail, and other trijets have 2 on the wings and 1 at the tail.

But most quadjets (again, only 100+ passenger jet airplanes) put all of them on the wings. Why not put 2 on the wings and 2 at the tail?

Such a configuration would save weight on the wings, because the wings wouldn't need to be so strong to support 2 outboard engines far away from the fuselage. If twinjets can be configured with both engines at the tail, then I see no reason why a quadjet cannot.

In fact, I know of one old quadjet that put all engines at the tail---the Ilyushin Il-62. So I do not think balancing the center of mass and center of pressure is a problem. Some trijets put all engines at the tail, whereas what I'm talking about would only put 2 engines at the tail (and 2 on the wings).

So is this a good idea? Why not do it this way?

EDIT: It was pointed out that exhaust from the wing engines would interfere with the rear engines. If so, then can't we borrow the trijet design for the intake? A large intake at the vertical stabilizer splits in half and feeds both rear engines.


texts: Is there a minimum start altitude for autorotation landings?

texts:
If a helicopter is flying relatively low, say for sightseeing, can it still land using autorotation if required?

What about if there was an issue during a routine landing? Is there any cutoff point where autorotation is no longer feasible?


texts: Why would aircraft take-off in the opposite direction as landing despite wind direction?

texts:
I have visited and flown out of Harare International Airport, Zimbabwe a number of times and the thing that always baffles me is: Why do aircraft use runway 23 to depart, but runway 05 to land?

At first I've thought that it may be a wind change, but it appears it's not the case. Is it because wind is limited at the airport and therefore direction does not matter? Or is there some special procedure for 'hot/high' airports?


texts: Why are airplanes parked at the gate with max rudder deflection?

texts: Quite often I see aircraft parked at the gate with rudder deflected to the max. I see this either with Boeing and Airbus aircraft so it must have been done on purpose. I know that there are dampers connected to the yaw, or are those not powerful enough to keep the rudder straight e.g. undeflected?


texts: How much does a typical private pilot pay for a non-training flight?

texts:
I realize one can expect to pay upwards of $10k to receive their Private Pilot certificate. Understood entirely.

However, my question revolves around the everyday expense of your average Joe pilot who wants to go out to the local airport and take up, let’s say, a Piper Arrow for a nice relaxing local flight around the area (we will say Kansas City Wheeler Downtown in this case). As a hobby. Maybe take a couple friends or family if they chipped in.

How much money could an average Joe pilot look to spend per flight, taking up a small craft, just because?


texts: Why is radio still the method of communication from the ground to air? If i'm not mistaken, cellular services should be much better in quality and reliability


texts: How significant is the lift induced drag contribution to total drag of aircraft at cruise speed? From what I've learned so far it seems to be around 10 to 15 percent of total drag. I suspect the ratio doesn't vary too much between aircraft provided they're within the same speed range. Therefore, let's focus on airliners and other high subsonic jets.


texts: Is there a specific reason Delta Airlines is allowed to have a call sign that's also code word in the NATO phonetic alphabet?

texts:
This is a followup to Is there any specific reason why Delta Air Lines doesn't have its own callsign? I was... "helpfully" informed that, um, actually, Delta Airlines does have its own callsign, it's "Delta".

So, let me try this again.

Having an airline callsign be the same as a letter code word in the NATO alphabet creates a huge potential for misunderstanding. Indeed, the controllers at Atlanta, Delta's headquarters, use "Dixie" for the letter "D", specifically to avoid ambiguity with the name of the airline. It seems to me that it would be much simpler to just assign the airline a different callsign. Is there any specific reason why this hasn't been done?


texts: Why does the FAA SPL require different endorsements depending on cruise speed?

texts:
Part 61 section §61.327 requires that sport pilots require separate endorsements for aircraft with a VH below 87 KCAS and aircraft above 87 KCAS.

What is the reason for two separate endorsements and what is the significance of 87 kn?


texts: Why are no recent small aircraft designed to be "characteristically incapable of spinning" as the Ercoupe was?

texts:
I'm a student pilot at a flight school that primarily flies RV-12s as a trainer. We had one day that through a booking error meant that all the RV-12s were booked so we had to use their Ercoupe 415-C instead.

I was surprised at how easy the plane was to fly and asked my CFI about the "characteristically incapable of spinning" placard on the front panel. He explained that the rudder pedals weren't necessary because the plane maintains coordinated flight by connecting the ailerons to the rear rudder.

I think this is an amazing innovation for the Ercoupe and I'm surprised it's not a design that I can find on any modern small aircraft designs.

Maintaining coordinated flight with rudder pedals isn't a complicated task for a trained pilot but it is another task that the pilot needs to perform. It seems like removing flight tasks from the pilot would make for a safer aircraft so why do manufacturers not include designs similar to Ercoupe's models?

Is it a weight/cost/drag issue, or are spins not as huge of a killer as they were in the 40s-60s?


texts: Ferry Permit for aircraft outside the U.S

texts: The aircraft originally had a U. S. airworthiness certificate then was exported to Brazil. It is now being sold to a company in the U. S. for U. S. operations. Can this aircraft be issued an "N" number and Ferry Flight permit for the purpose of returning to the U. S. where an application for U. S. Airworthiness Certificate and permanent registration will be pursued?


texts: On a chart, how can I find the frequency for flight following?

texts: Is there a map I can refer to in order to pick up the correct frequency for VFR flight following while enroute? I know I can request a frequency from ATC as I depart, but what if I want to fly around and do sight seeing, practice maneuver for my checkride etc. for a while, then pick up flight following for the remainder of the trip?


texts: At what altitude should I join overhead a fix when my legal MSA is lower than the holding altitude?

texts: For example, if my MSA is 4600ft and the holding altitude is 6500ft, am I legally allowed to join overhead the fix at 4600ft, or do I need to join overhead the station at 6500ft?


texts: Why is YF22 designed with conventional rudders while YF23 with all-moving rudders?

texts:
Are all-moving rudders more stealthy? If so, how come YF22 which is just as fixated with rear body stealthiness as the YF23 comes with conventional ones?

Also, all-moving rudders have fixed camber, which means they are far more efficient during supersonic flight, right? Another reason for an all-moving design.


texts: The airbus A350 aircraft when being refuelled seems to drop when the wings are filled.How  much is the drop from empty to full.Thankyou


texts: What is the sequence of ATC frequencies for final approach at JFK?

texts:
Recently I was listening to liveATC.net and tried to understand the sequence of operations for the voice communications.

However, it seems that there are a lot of frequencies for the approach procedure, and I got confused by their names and jobs. For example, the JFK terminal has two approaches (CAMRN 128.125 and ROBER 125.700), one Final approach (Final 132.400) that I don't really know what it is, and one two Tower frequencies (123.9 and 119.1). So the question is, (1) I think the tower will be covering the final approach but what is the "Final 132.400" frequency for? (2) when and where (e.g., distance from the airport) the aircraft will be handed over from one frequency to another? Does the tower frequencies only cover up to 5 nautical miles from the airport?


texts: What are the pilot rating requirements for amphibians?

texts:
I know that both land and sea planes require pilot ratings in order to act as pilot-in-command.

What is the requirement to act as pilot-in-command of an amphibian?

Is there a third rating or just seaplane and land ratings?

What about flights taking off and landing exclusively on either water or land but not both?


texts: Why are so many small private jets sold just after a few years?

texts:
Why are so many small private jets sold within few years? Hardly a year or two, with depreciation of over 1-2 million dollars?

I understand these are bought by millionaires. But everyone spends some time while making such a huge investment. I presume they decided to own the aircraft and might have tried it for a few hours before procuring one. Hence, being stupid, repenting and selling it off for the majority of the buyers.

If millions are peanuts for an owner, he would be into the bigger jets like Learjet or Gulfstream.

So, why are smaller jets with < 12 pax sold in the used market so fast? Of which many hardly have ~200 hours on them. This doesn't make any economic sense to a small millionaire.

Are there any additional benefits (e.g., tax benefits) by spinning off an airplane the next year after procuring it?


texts: What concerns do the FAA and EASA have in 2014 with "own-ship position display" on EFBs?

texts:
I've read a couple of times that "own-ship position display" is not authorized for use on Class 1 or 2 EFBs (by the FAA), and that both the FAA and EASA are cautioning against that feature's use on EFBs in general. Own-ship position is an aircraft's GPS position displayed against georeferenced charts and diagrams.

Obviously the use of a portable device - iPad or otherwise - should not be enough for primary navigation, but what safety concerns do the authorities have with own-ship display?

Specific accident reports or official citations would be great.


texts: Do ETOPS requirements vary between passenger, cargo, and non-revenue flights?

texts: Are there different ETOPS requirements for aircraft depending on usage?  For example, does a FedEx cargo flight need the same ETOPS ratings for over ocean flights as a passenger flight?  Also, how about ferry or repositioning flights which are not revenue flights?


texts: Did A320 NEO need an equivalent to 737 MAX MCAS because of its bigger engines?

texts:
We read that MCAS on the Boeing 737 MAX was needed because of the new, bigger, heavier engines of the MAX compared to the previous 737 versions.

The closest equivalent to MCAS on the Airbus A320 NEO is the alpha protection even if they are not the same.

But what have been the adaptations to the A320 due to heavier, larger engines?  Can we be sure that A320 does not suffer from issues comparable to those the 737 MAX has, due to their similarities (bigger engines on same airplane)?


texts: Why can't sonic booms be heard at air shows?

texts:
At air shows with fighter jets I would expect there would be a demonstration of supersonic flight. But in this flight of a Eurofighter Typhoon, no sonic boom was heard.

What is the reason?

Is it that there is no supersonic flight involved due to loudness or needing a bigger distance to accelerate?

Or is the sonic boom inaudible for a reason related to the short time delay of the sound between the noise source and the microphone, or some other physical reason?


texts: What airframe design is best for stormy weather?

texts:
Consider picking a plane for weather study. This plane will intentionally fly into weather systems (e.g. inside the eye of a hurricane) to collect scientific data. It will be equipped with on-board weather radar and other atmospheric sensors.

Which airframe designs are most suitable for this type of flying?

4 engines is probably a must for reliability
Piston? Turbo-prop? Turbo-fan?
Low wing? High wing?
Low / high aspect ratio?
Delta wing? Sweep wing?
Conventional tail? T tail?

You get the idea...

EDIT: I would also like to know why the current planes are chosen. For example, if delta wing is not used, then it suggests a certain criteria which cannot be met by the delta wing design (e.g. requires high AoA at low speeds).


texts: What is the meaning of R88/70D in this METAR from Ashgabat International airport?

texts:
The following METAR is from Ashgabat airport (UTAA)

  UTAA 071300Z 13006KT 9999 FEW050CB BKN050 BKN100 15/06 Q1013 R88/70D
  NOSIG

What does R88/70D mean, I couldn't find any references?


texts: Is there a way to calculate the difference in pitch required to reach a certain vertical speed?

texts:
I am programming an autopilot for a 787 flight sim software and I've been having a problem.
I'm trying to simulate a PID that controls the pitch of the aircraft In relation to the vertical speed selected. I'm not sure how to obtain the difference in pitch required to get to a certain vertical speed in fpm and keep it stable there. Any advice and input is appreciated.

Edit:
Posted updated question on a more suitable stackexchange forum:
https://robotics.stackexchange.com/questions/16249/needed-help-with-pid-for-an-airplane-autopilot-system


texts: What are the FAA sport-pilot self-certification standards?

texts:
Consider a hypothetical pilot who knows they have a medical condition which the FAA considers disqualifying (under the standard medical qualification standards). Is that pilot permitted to operate under sport-pilot privileges if they do not believe their condition interferes with their ability to safely perform their sport piloting duties? Must that pilot consult with a private physician? If so, must the physician offer some sort of approval?

The FAA has a similar question on the FAQ, but doesn't seem to answer it fully. They "suggest" consultation with a physician. Does that suggestion indicate a pilot who does not do so is in violation of a FAR?

edit: This question is concerning operation of a powered airplane.


texts:
Since the world population shows no signs of slowing down its rapid increase, it's pretty safe to say that means we can only expect more concurrent flights as time moves forward.

Is it physically possible (with current aircraft models) to further reduce RVSM to say 500ft?

Since automatic altitude maintenance is required when flying in this airspace, I can't see why not.


texts: Why do pilots need the ceiling, time, and dew point in the ATIS?

texts:
For example:

Ceiling: what is the ceiling? Why do they need to know the ceiling?
Zulu time: what is the zulu time?
Dew point: why do they need to know the dew point?


texts: In what portion a non-GPS approach, can a pilot legally fly with GPS as primary navigational resource?

texts:
In IFR-GPS-equipped (/G) aircraft, a pilot flies most of the segments with GPS as primary navigational resource* even the route is along victor airways or VOR radials. However, when we start the approach, we have to switch the nav source from GPS to the nav source specified for the approach. In this context of using GPS for non-GPS approaches,

When should a pilot switch away from GPS? Is it from an IAF, FAF or upon ATC vectors to intercept the final approach course?
If the a pilot executes a missed approach, when can the pilot switch back to GPS? Is it when established on course direct to the holding fix?

*By primary navigational resource, I mean it provides the signal/data source for the CDI needle on a HSI, that a pilot, autopilot or flight director refers to make actions or action suggestions.


texts: Can the FDR be interfered with in-flight?

texts:
Can an FDR on a Boeing 777 be interfered with or vandalised during flight?

If this has happened on MH370 then the black boxes may not yield any data if found.


texts: How many angle-of-attack sensors does the Airbus A 320 NEO have?

texts:
Are there 3 x AOA-sensors on all the Airbus family planes? In the Airbus flight manual there is one AOA-sensor called 'stand-by'. What does that mean?

Are all 3 AOA-sensors heated and can the actuall temperature of these sensors be monitored live by the pilots during flight?


texts:
Note: not a duplicate of Can biplane or triplane designs be revived with modern materials?

This question compares a high performance triplane with high aspect ratios and high gap, to a monoplane. It does not explore materials engineering.

Wouldn't a triplane be much more efficient than a monoplane of same wing area?

Take a small GA plane, 1,000 lbs, 100sq ft of Wing area, 25' span, 4' chord, a pretty typical LSA/microlight. So, an aspect ratio of roughly 6, and a wing loading of 10psf.

NOTE:  With a gap of 2 chord, I understand the efficiency of multi wing aircraft is almost the same as a monoplane. see graph.

Now make it a triplane, which reduces the chord to roughly 1.3, increasing the aspect ratio from 6 to 18, just like a glider.  That's a 300% increase in efficiency, no?

Instead of a heavy spar for a thin wing, you could just put the stabilator at the wing tips joining the 3 wings: so no extra wing strut interference drag ( expect for a small amount of extra interference drag at 2 wings roots).

So:

less weight( same wing area, but smaller lighter wings),
smaller engine needed ( so could even go with smaller wing area)
less induced drag (due to 3 times the aspect ratio)
a less form drag ( same span, but thinner wings (66% THINNER(??) due to 66% smaller chord)
a little more wing root interference drag,
no extra wing strut interference drag
less induced drag due to 1/3 the wing loading

NOTE: All this could only happen with a gap of 2 chord or more, where I'm told 2 wings act independantly without interfering with each other, just like a main wing and horizontal tail( which is a biplane of sorts)

Is this correct, at least conceptually?


texts: Flying VFR in uncontrolled airspace, what to do if one spots an apparently out-of-control fire on the ground?

texts:
Suppose I'm flying VFR in class G (uncontrolled) airspace, monitoring the local CTAF frequency while doing so. Maybe I'm alone in doing circuits around the local airport, or maybe I'm practicing navigating by landmarks, or maybe I'm on a cross-country flight from A to B. Either way, there is no one else in the immediate vicinity making themselves known on the radio, and (unlike in controlled airspace) there's no obvious ground station that I can call and expect to get an answer from.

Now, I, or someone else onboard, spots a fire on the ground some distance away.

A good first step then seems obvious, to go closer to get a better look. Now suppose that, on closer inspection, this does indeed appear to be an out-of-control fire with no firefighters on site. This could mean either that nobody yet knows about it, or that rescue services have been alerted but are still on their way.

It could be a structural fire, or a forest/field/grassland/etc. fire. To the extent that this makes a relevant distinction, it'd be great if answers addressed both types. (Both of these have happened recently in my immediate area, though I don't think they were initially reported by aviators.)

For me, a thousand feet or more above ground, what's the next step?

The aircraft isn't in any immediate danger, so from the perspective of the aircraft and its occupants, it's not an emergency or even urgency situation. However, there's certainly risk to property, and possibly people, on the ground.

Should I dial in 121.5 on the radio and call mayday? Or pan-pan on 121.5? Or should I use some other frequency, such as that of the local area control if I were to climb straight up into controlled airspace? (They would also be monitoring 121.5, so I would effectively be reaching the same people.) Mayday, pan-pan, or not? Or something else entirely?

Not doing anything in particular and just going on with my day doesn't seem like the right thing to do in such a situation.

Looking at my radiotelephony textbook, urgency traffic (pan-pan) includes situations relating to the safety of a "vehicle" (not just the aircraft, but specifically including any aircraft) or for a person onboard or within sight, but that do not require immediate assistance. Emergency traffic (mayday) includes situations involving "serious and/or immediate danger" (unspecified as to what) where immediate assistance is required.

I'm interested primarily in answers pertaining to the EU.


texts: What's a quick way to determine which runway to use?

texts:
Let's say I call up Wx and have the wind direction and I know the runway headings from my charts and the pattern is empty. I can do the math, but it's tedious and slow and even worse when there are multiple runways. This is what I usually do:

Runways are 13 and 31
Wind is 253° which rounds to 25
$25-13=12$
$31-25=6$
I'm going to use Runway 31

Is there a trick to determine best runway quickly without doing the math?


texts: When to turn during missed approach when MAP not identifyable

texts:
Not a duplicate of When to go missed on a non-precision approach? please read carefully before duplicating this contains some subtle points. Reposting after clarifications that emphasise this is a different question

According to AIM 5.4.21 (b): When an early missed approach is executed [...] fly the IAP as specified on the approach plate to the MAP at or above the MDA or DH before executing a turning maneuver.

Hence if a pilot decides on a missed approach, he needs wait until over the MAP to execute any turns of that procedure. One can only assume that is meant to prevent a climbing turn into a nearby protected airspace.

The following scenario puzzles me.

A pilot executes a LOC approach with a missed approach consisting of "Climb to 1000' then left climbing turn to 5000' direct to..." Sometime after the FAF the cockpit timer breaks. The MAP can no longer be identified by time. The pilot immediately starts climbing to 1000'. But when to start the left climbing turn to 5000'?

The aircraft does not have other equipment that would positively identify the MAP, when is that pilot required to begin that turn?
The aircraft has a DME and a functioning timer? Which is preferred to identify the MAP? Is the pilot allowed to change from timer to DME after having initially started using the timer for MAP identification upon timer becoming unusable or does equipment malfunction mandate execution of a missed approach?


texts: What makes a jet single pilot certified?

texts: Why are some small-ish jets (Embraer Phenom 300, Pilatus PC-24 for example) single-pilot certified? The pilot still has to fly+navigate+communicate. Why would a small jet be more manageable than a bigger jet? Or is it more the case that they would not kill as many people if things go belly up?


texts: Do propellers have any lead/lag mechanism?

texts: The fan blades in a fanjet are mounted loosely in a fir-tree shaped mount so they are free to lead or lag and balance themselves. The blades on fully articulated and semi-rigid helicopter rotor heads are mounted with a drag hinge that allows them to lead/lag as needed. Do any propeller aircraft have a method to allow the blades to lead/lag, or is this for some reason unnecessary?


texts: What are these "pimples" on the jet engine for?

texts: When looking into the General Electric CJ 805-23B jet engine, I have discovered that all forward section of the compressor is covered by a number of near identically looking "pimples". What are these tiny devices for, what are they doing? And why only front section of the compressor has them?


texts: Is the MD-11's third engine slightly nose up?

texts: From my visual inspection, the third engine (the engine on the horizontal stabilizer) is slightly "nose up", especially compared to the engines on the wing. That means, the front part of the engine is lifted slightly. Am I correct? If yes, what is the intention?


texts: why the front shape of the engine of Boeing 737 aircraft is not round ?? can anyone explain ?


texts: What are the differences between the MiG-15 and MiG-17?

texts: Apart from the extra wing fence and angled leading edge of the MiG-17, what are the differences visually between the two aircraft?


texts: Why are there vortex generators under the Boeing 737's cockpit windows?

texts: What is the purpose of the vortex generators located right in front of the Boeing 737's windshield?


texts:
Is there any no air proof design for the wings? Or are  some of the parts are equivalent to outside pressure and some have gauge pressures?

Are some parts airtight and others not?


texts: Is it worth it? Spending loads of money and years?

texts:
I'm a high school student. Over here in India, there are too many people and less jobs. I have a passion and a dream to become a pilot in one of the distinguished commercial airlines of the world. I have researched all the data and know all the facts.

The question which comes to my mind is:
Is it worth spending more than US$80000 for all the training, type ratings and education and still not being capable to end up with a job?

The number of hours required for ATPL are 1500 here but we land up with approximately 310 after University and CPL. How do I increase my flight hours after that? How many years before I'll get a proper job? Is it worth spending so much money and time?

Please let me know guys! I'm not sure whether i should continue in this field or not.


texts: Why do passenger aircraft have the little airjets over each seat?

texts: I never turn them on, but I do turn them off if I notice them. Is this a relic from the age when people lit up next to you and you wanted to blow away the smoke? The system must weigh almost a ton on a large aircraft and seems pretty unpopular and hard to maintain.


texts: What is the difference between a VOR and a VORTAC?

texts: Confused about the difference between a VOR and a VORTAC?


texts: How would a low-airspeed fixed-wing drone be designed to reduce effects from gusts and wind shear?

texts:
In a story I am working on, the characters need a fixed-wing drone that can rendezvous with a blimp, where by "rendezvous" I mean "come within a very short distance at low relative airspeed".  The challenge is that the blimp will typically be flying through powerful gusts and abrupt wind shear—ideally hurricane-like conditions or worse.  The characters have the time and resources to design and build a custom drone for this purpose, and while I realize that I will probably have to stretch credulity at some point, I'd like the drone's design to at least seem plausible.  Hence my question: What would a drone custom-built for such missions look like?

Here's what I found so far (and which I hope is accurate):

Wing loading is the single largest factor in gust response.  If the only concern were dealing with the wind, the drone would have as much wing loading as could be managed.  However, I also need the rendezvous to happen at low (blimp-relative) airspeed.
A long wingspan is a liability in wind shear, increasing the chance for an asymmetric stall and upping the rolling moment even if there is no stall; the drone should probably have its wings tucked tight to its body.
Given the risk for sudden stalls, the wings should be designed with substantial washout.  They will probably not be swept (in either direction), both because drag reduction is not a driving consideration and because swept wings would tend to push the drone nose-up in a stall.
Anhedral wings, while less good for stability, would cause the drone to bank into crosswinds, which could be useful given the feedback delay the drone pilot has to deal with, and some of the stability could be made up by placing the wings high, creating a pendulum effect.  But maybe stability is the more important factor here.
An inverted tail will cause the drone to both roll and yaw into crosswinds.  I am not sure whether an inverted T or inverted V would make more sense.

I have also found some planes that are intentionally flown into hurricanes: the Lockheed WC-130, the Lockheed WP-3D Orion, the Gulfstream IV, the Douglas DC-8, NASA's ER-2 (a Lockheed U-2 derivative), and the AAI Aerosonde, the only drone on my list.  The last, at least, backs up some of the ideas I have above.


texts: Where to find a waypoints/fixed points, navaids and airports database?

texts:
I wonder if it is possible to download a database with waypoints, navaids, airports and airways between them. I've been working with AIP documents but it's difficult to get raw information from them and they only have information about waypoints.

I happened to find skyvector.com and I thought there would be an easier way to obtain that amount of information.


texts:
Induced drag is proportional to the square of span loading. The normal method to decrease it would be to increase span. This, however, leads to an exponential weight increase.
So, my question is, if tandem wings are placed with a large longitudinal gap, so as to avoid downwash, would they act as independent wing spans sharing the weight of the aircraft to reduce induced drag? If so, how large would this gap need to be? Would one at the nose and another at the tail be enough?


texts: What is the technical term for ARINC 429 data injected into a heartbeat stream going to an LRU?

texts:
I am going to describe a type of communication protocol that I've seen used with ARINC 429 and would like to know if there is a proper name and classification for this type of communication... Anyway, I'll try to describe as accurately as possible.

So there is an outgoing stream of communication (like a heart-beat) that an LRU expects to receive. The LRU also expects to receive certain data on that same heart-beat bus... So, you'd have to sort of inject the ARINC word data into the heart-beat stream temporarily to send it to the LRU.

Is there a name for that sort of communication?

I think I've also seen similar protocols with serial communications... Where a data stream (heart-beat) is always being sent, but the pay-load changes when you need to transmit/receive meaningful data.

I am looking for the technical terms to describe this communication process.


texts: Launch control equivalent while take-off

texts: What is the proper term used when the plane is stopped and the engine is ramped up and after a certain thrust is reached, it suddenly starts off with a jerk.


texts: What are static discharges for on an airliner?

texts: I have never noticed these on any boeing planes before, so why are these on airbus a320 series and not on the boeing 737 and also what are they for?


texts: What does an owner/operator need to do to legally rent out their aircraft?

texts:
I am interested in knowing all regulations apply to about what an owner operator needs to do to legally rent their aircraft out for private/business usage or flight instruction.

What inspections?
Insurance requirements?
Anything else?

I assume renting your aircraft out is under part 91.


texts: Do pilots keep light in the cockpit during long night flights?

texts:
During long times of the cruise flight, is the internal light normally switched on or off inside the cockpit?
Knowing it is generally dark in the night would make a smartphone-based night time logger easy to write.


texts: What runway alignment should I expect from a straight-in approach?

texts:
More precisely, in the case when a straight-in approach is present, what is the maximum angle between the final approach course and the runway heading for a straight-in minimum apply?

I had thought it is 15° for GPS IAP and 30° for others. However, when I looked at RNAV (GPS) RWY 28L @ KMRY, the angle is |279.4° - 261°| = 18.4° > 15°. Is there any other rule that applies, or is this simply an exception?

Note that on IAP runway diagram (bottom-left), there is usually an arrow with a distance from FAF to MAP and course direction, and they are omitted here.


texts: How many displays does an ARTCC Air Traffic Controller view and what is displayed on each?

texts:
I am trying to figure out the relation between the data sent to a center (ARTCC = Air Route Traffic Control Center) air traffic controller and the displays they view. Did the workstation change when En Route Automation Modernization (ERAM) was implemented?

I am really just looking for a general description of a center air traffic control workstation (if it varies based on the type of controller I would like to know any significant differences).


texts: What is the exact responsibility of the Landing Signal Officer on an aircraft carrier?

texts:
From Youtube:

There are three LSOs apparently working at the same time, providing indications to the pilots:

What is the exact role of the LSO?
Why three? All of them holding a wave off switch.
What is the reason to have pilots guiding pilots rather than a computer?


texts: Which authority regulates airliner design?

texts: To which regulating authority's regulations and standards are large sub-sonic transport aircraft (passenger or cargo) designed? The FAA's, or EASA's, or both?


texts: At what exact point in time should we be giving the 10 minutes to diversion call to ATC?

texts:
I wanted to get some clear information if it’s available as to which exact point should the 10 mins to diversion call be given to ATC with respect to our FOB. The way I have been doing it currently on the A320 is by looking at the FUEL PRED page and when that shows a time value equivalent to 10 mins I give the call to ATC. But this is not a very reliable way to do it while in a HOLD. As the FMGC only updates the extra fuel and time value after crossing the waypoint/PPOS/pseudo waypoint at which the hold has been inserted.
This 10 mins to diversion call is mainly given while flying in India to let ATC know that we only have 10 mins worth of extra fuel left for holding beyond which a diversion will have to be initiated to our filed destination alternate.
Is there any precise way to calculate when we will exactly be at 10 mins?


texts: Why isn't Vy lower than the speeds for best L/D ratio and best glide ratio in an airplane with a piston engine and a variable-speed prop?

texts:
This answer to a related question implies that if the power available were constant regardless of airspeed, Vy would occur at approximately the angle-of-attack that yields the minimum sink rate with power idle, which occurs near the airspeed for the max ratio of lift coefficient cubed / drag coefficient squared, slower than the airspeed for max L/D ratio.  The airspeed for best glide ratio should be only a little slower than the airspeed for max L/D ratio, to minimize the extra drag from the stationary or windmilling prop.

Therefore it would seem that in an aircraft with a piston engine and a constant-speed propeller, Vy should be slower than the best glide speed.  Yet this manual for a Cessna 182 gives the best glide speed as 70 KIAS, and gives Vy as 78 KIAS at sea level and 72 KIAS at 10,000' MSL (page 4-14.)  So why is Vy faster than the best glide speed in this aircraft?  Why isn't Vy slower than the best glide speed?

In essence, this is a question about what the power-available curve looks like for an aircraft with a piston engine and a variable-speed prop, plus a question about what other factors may be at play here.

Is less power available at lower airspeed?  If so, does that imply that less manifold pressure is available at lower airspeed?  Presumably the throttle would be fully open in a climb at Vy -- is the engine unable to turn at the optimum RPM for maximum power when climbing at Vy?

Does the answer have to do with the fact that even with a constant speed prop, at most airspeeds, the pilot cannot simultaneously optimize the RPM of the engine and the angle-of-attack of the prop?  And thus the power available (given that RPM and manifold pressure are kept within safe limits) is not constant as the airspeed varies?  Since there is no variable transmission (variable gearing) between the engine and the prop, it would seem that this would be an accurate description of the situation.

(Naturally, the designer of the prop can simultaneously optimize the angle-of-attack of the prop and the RPM of the engine by selecting the appropriate prop diameter, chord width, blade twist, etc, but it would seem that this optimization might be only valid at one particular airspeed, even with a variable-pitch or constant-rpm prop.)

It would seem that in an aircraft like a Cessna 182, the maximum achievable steady-state climb angle would be shallow enough that the "unloading" of the wing during the climb is not very significant, so that essentially the same correlation between angle-of-attack and airspeed exists in climb, horizontal flight, and gliding flight.

Here are some other related ASE questions and answers--

Why is best angle/rate of climb indicated in airspeed? -- informative, but it is unclear whether the graphs are meant to represent the case of a fixed-pitch prop or a variable-speed prop.

Does a windmilling propeller create more drag than a stopped propeller in an engine out scenario? -- informative, but it is unclear whether the "best glide" airspeed in a typical pilot's operating handbook would represent a stopped prop or a windmilling prop.

Is Vy closer to Vbg with a variable pitch prop -- closely related to the current question, but the actual body of the question is phrased entirely in terms of a fixed-pitch prop.


texts: What is the area between the taxiway and runway shown in the picture below?

texts: Is this the Arresting area? I'm not too sure what you call this area


texts: Do "air ferries" for civilian vehicles still exist?

texts:
In the 1950's and 1960's, there were vehicle (and passenger) air ferries operated by planes such as the Bristol Freighter. Mostly across the English Channel (England to France), by companies like Silver City Airways and Channel Air Bridge.  In other words, your car travelled with you on the same plane.

On that route, sea ferries (and hovercraft) eventually killed them off financially.

Do similar scheduled air ferries, for civilian cars and their passengers, still exist anywhere in the world?  If not, why?  Is the reason just financial, or are there no suitable planes any more, or did new safety or security rules make it impossible to operate them?

They would seem well suited to short hops like the Scottish islands, islands off British Columbia or Alaska, Indonesia, the Caribbean islands, and so on.  Especially in locations where the sea crossing is rough and unreliable.


texts: Can hours accumulated in a glider count towards the 1500 hours for an ATP certificate?

texts: If you have ratings in Glider, ASEL, AMEL do all your PIC hours in all categories count towards an ATP certificate, or must the Glider hours be kept separate?


texts: If "flight time is compensation", how can a PPL holder legally fly at all?

texts:
I have seen a strange phrase "flight time is compensation" in a few questions and answers here, mostly related to what PPL can do for free and what is not allowed.

This looks so confusing that I ask a question. If the private pilot cannot get the compensation, and flight time is a compensation, how could such pilot legally fly? One should theoretically get CPL before having the possibility to log any flight time.

This is surely not the case, I understand. When the "flight time is compensation" and when it probably is not?

Most of the confusing questions are related to USA (so FAA).


texts: What are the advantages/disadvantages of diesel/Jet A-1 piston engine?

texts:
Some GA aircraft, notably the DA40/DA42, are equipped with piston engines that use Jet A-1 and/or automotive-grade diesel instead of aviation gas (avgas). An example of such engine is the Austro Engine AE300:

What are the advantages/disadvantages of these engines and why are they not more common?


texts: Were civilian aircraft allowed to overfly the Soviet Union?

texts:
The great-circle route from Western Europe to, say, Japan involves putting in a lot of miles above Russia, for example like this (London Heathrow–Tokyo Narita; map from gcmap.com).

Would routes like that have been possible during the days of the Soviet Union or would civilian planes have had to take a more circuitous route, flying south of the USSR and maybe even avoiding the Warsaw Pact countries, too?

I'm aware that at least some of Soviet airspace was prohibited which, for example, led to the Soviet Air Force shooting down Korean Air Lines flight 007. Presumably, the route shown in the map would be prohibited, since it goes over the Kola Peninsula, where the Northern Fleet is based and Novaya Zemlya, a major nuclear weapons test site.


texts: If Space Shuttle flies "like a brick", why does it need the wings?

texts: I have seen the Shuttle named a "flying brick" multiple times.  However a brick, as understood in the building industry, is a simple rectangular shape without wings and without any adaptation of the form. If the Shuttle was only capable of that much, why could not it be a lifting body like  Martin Aircraft X-24?


texts: What do air traffic controllers do on a slow day?

texts:
We all know air traffic controllers have one of the hardest, most stressful jobs on the planet... day after day they handle thousands of aircraft with the cool of a seasoned gunfighter and the surgical precision of a Jenga-playing robot.

But what about when there's no aircraft around? Perhaps it's freezing rain and there no chance of an aircraft landing. Or perhaps the (extremely) high volume of flight training at a particular field suddenly drops to nearly zero over spring break. Or maybe fate and luck just got together and no one wants to go to that airport today.

What do controllers do when there's no aircraft in their area, and especially what do they do when there's not likely to be any aircraft for an extended period (1+ hours)


texts: What trade-offs does an airline make when selecting an engine type for their aircraft?

texts: So it is my understanding that on most commercial jets, the airline has a choice of multiple engine types, such as GE or P&W, etc. My question would be why an airline would choose one type over the other. Also if there is a "better" choice, why would the airlines choose one of the others?


texts: How should control surfaces be modeled in simulations?

texts:
I am modeling the lift and drag forces of a wing in software of my own creation.

If I have a wing which fits the profile of (for example) NACA 0024, it is a simple operation to look up the proper coefficients for lift and drag based on the current angle of attack for the wing.

But what happens if I slap an aileron on the trailing edge?

Do I need to re classify the wing based on the new geometry?
Should I treat control surfaces as their own aerodynamic bodies and look for lift/drag tables for them?
Since this is just a simulator, would it make sense to just offset the current coefficients by some value based on angle of deflection?

I am admittedly uneducated in aerodynamics and aviation, so please forgive me if I've come at this problem from entirely the wrong direction.
Any help or advice would be greatly appreciated!

Thanks!


texts: How come Boeing invested \$32 billion on the 787 program and Airbus only \$15 billion on the A350? (according to wikipedia)


texts: What "jet engine" is featured in this ad that Simone Giertz made for a phone?

texts:
Simone Giertz's video "Having Dinner With a Jet Engine/Leaf Blower" has a number of views of the turbine, on a cart, with a ducted fan attached.  This side view is the best view, in my opinion.

I put "jet engine" in quotes in the title because it doesn't seem like it's trying to produce thrust via exhaust, it looks like a turboshaft or turbine generator or maybe APU where the power is supposed to go into the output shaft and the hot exhaust just comes out the side, slow.  I'm guessing the ducted fan is an add-on but am not sure.

There's also a good shot of the control panel during start-up.  I haven't immediately noticed one that shows operating RPM.

At least one shot also shows a nameplate top-front on the compressor section but it's not in focus and I can't make it out.

I feel the need to postfix this with:  I am not in any way affiliated with Simone Giertz or Google.


texts:
aviation pros!

New to the aviation/RC world and would like to ask a serious question about using composites for the skin of a UAV I am developing my first time out.

Want to use carbon fiber for a planned UAV approx 6-8 feet in length and weighing in at about 200 lbs powered by electric motors.  But, instead of making a carbon fiber skin from a stryofoam (or similar) mold, I am thinking of printing out the skin (using a carbon fiber filament) from a large format 3-D printer as separate panels up to 20" x 20".  They would then be attached to the UAV's metal airframe (of a semimonocoque style).

It just seems like a much simpler way than molding the skin from a plug.  Yes, I am concerned about the necessary strength and elasticity needed from the skin but I am hoping that a well thoughtout design for the panels (and especially for the nose and empennage) along with a CF/nylon filament will provide that.  I have also considered the production time and filament costs associated with this method, but it just seems so darn simple and easy.

But what do the pros think.

Thanks.


texts: Is the air bleeded from the engine to maintain cabin pressure for airlines heated or cooled.  If heated, what device is used, if cooled, what device is used and in both cases how much energy does it draw for both the former and the latter


texts:
Why must VR (Rotation Speed) be set so precisely? I mean why can't they just say:

  Rotate the Aircraft at 120 to 150 knots

And then, the pilot thinks:

  OK, I have a full plane and half full tanks, I think I will rotate at around 135 knots

And then rotates at around that speed?


texts: How to interpret/use "Fix Minimums" (at KALB)

texts:
This one stumped both myself and my CFI. Im specifically asking about the minimums at KALB IL/LOC 19 but a general answer is also appreciated.

The plate lists two distinct sets of minimums and we were confused about the S-LOC 19 minimums. The first set seems like the obvious regular ones and takes you to the labeled step down altitude. Then there is a second set for WESTS FIX MINIMUMS that are lower to the first set.

What is this second of set of minimums for and how can they be utilized?

It seems a bit odd that they reference an altitude below the step altitude. Presumably you fly 820 to 0.7 on the DME, but yet the WESTS FIX MINIMUMS seem to allow for lower than this.

(full plate for reference incase it changes)


texts: Has a general aviation twin-engine turboprop with counter rotating propellors ever been built?

texts:
In my experience with general aviation twin-engine turboprops I've never heard of one with counter rotating propellors. I've never seen any data about an engine manufacturer building left-rotating turboprop engines.

I'm also curious if any counter rotating twin-engine turboprop aircraft exist outside general aviation as well.


texts: What was the Space Shuttle's glide ratio?

texts:
The Space Shuttles glided to a landing in the atmosphere after reentry. They were not good gliders, aerodynamically speaking, so their glide slope angle was rather steep.

What was the glide ratio of the Space Shuttles in this phase of flight?


texts: Where to find the LSA exporting requirements from the USA?

texts: I'm planning to visit the US to buy an LSA (light sport aircraft) then export it to Saudi Arabia, I'm not a US citizen, where to find the requirements?


texts: What is the largest flight school in the U.S. that does not offer a degree?

texts:
Definition of "largest" for the purpose of this question: the greatest number of flight operations per year on average.

What is the largest flight school in the United States that does not offer a degree?


texts: What is the correct equation for rotor solidity?

texts:
I'm working in a project that uses"blade solidity ratio", or "rotor solidity", the problem is, there are several articles which defines the equation in a different way changing in the section of the Radius analysis. I found 3 equations that I will describe below:

$$1. \frac{Nc}{2πR}$$ $$2. \frac{Nc}{2R}$$ $$3. \frac{Nc}{R}$$
N=Number of Blades, c= Chord Length, R= Radius of the rotor

Which one is correct or there is some case where each of this equation is applied?
Thanks.


texts: Which way (if at all) do the ailerons need to be deflected in a full-rudder sideslip in a Cessna 152 or 172?

texts:
Do you typically have to maintain an aileron deflection in a constant-heading full-rudder sideslip in a Cessna 152 or 172? If so, in which direction?  And why -- what is the source of the roll torque that needs to be countered>

Note that aileron deflection is not the same thing as bank angle.


texts: Why is it more difficult for ATC to manage a larger airliner?

texts:
After playing a few ATC simulation games, and reading at a few places (don't remember where), I am certain that it is more difficult to manage a larger airliner for the ATC.

Suppose that one A320 and one A380 is trying to land at a certain airport. In another case, if two A320s are queuing up for landing, what extra precautions would the ATC have to take in first case, mainly in separating the aircraft and ensuring that they are on time?


texts: What is the "on condition" concept of aircraft maintenance?

texts:
"On-condition" appears to mean that a component should be "fit until failure" or that the maintenance should only be performed upon failure of the component.

This seems problematic.

Can someone help me to understand why some components are handled this way and not as part of a regular inspection schedule of some kind?


texts: When do the Boeing 737 Next Generation aircraft reach End-of-life?

texts:
When can we expect the Boeing 737 Next Generation aircraft to reach End-of-life / stop flying?

The Next Generation is the name given to the −600/-700/-800/-900 series of the Boeing 737 airliner.


texts: Do helicopters try to take off and land into the wind?

texts: When helicopters take off and land is it preferable to point the nose into the wind? Since a helicopter is providing its own lift does it matter which direction wind is coming from?


texts: How were the fuel tanks sealed on the XB-70 Valkyrie?

texts:
The Valkyrie flew at Mach 3.1, close to the SR-71's operating speed in cruise. For the SR-71:

Fuselage panels were manufactured to fit only loosely with the aircraft on the ground. Proper alignment was achieved as the airframe heated up and expanded several inches. Because of this, and the lack of a fuel-sealing system that could handle the airframe's expansion at extreme temperatures, the aircraft leaked JP-7 fuel on the ground prior to takeoff. (Wikipedia; emphasis mine)

And if my memory serves me well, and if Discovery channel got it right, the SR-71 needed to meet with a tanker right away because of this leakage.
What was the Valkyrie's workaround/fix? The Valkyrie's Wikipedia article doesn't mention leakage prior to in-flight expansion.
I wanted to initially ask about the MiG-31's fuel tank seals, as the USSR developed heat-resistant rubber[1] (and also special fuel like the SR-71 – the T-6) for that purpose, but since the MiG-31 is a lot cooler, it wouldn't have been comparable, though this piece of information might be relevant.

1: Wings of Russia TV documentary


texts: Are QDM and QDR the same as 'inbound' and 'outbound' courses?

texts:
I'm about to take my last test to join an airline: the simulator. I've been told they ask to perform some QDR/QDM interceptions, as well as radial ones.

About QDM/QDR:

QDM: Magnetic course from the aircraft towards the station.
QDR: Magnetic course from the station to the aircraft.

I guess we all may agree with that. But:

Could we always take QDM as an inbound course? E.g. the aircraft is at 'radial' 180 and the examiner tells me: "Intercept QDM 320". That would be the same as saying "intercept the inbound course 320", right?
The opposite for QDR. Shall I take it as always an OUTBOUND course?

Probably QDM/QDR is used for NDBs and for practical uses they cannot speak about a radial, but anyways I'd like to know if my points are correct.


texts: How does Reynolds Number affect skin friction drag?

texts:
I'm an aerospace engineering student, and I'm worried about efficiency as it relates to high and low Reynolds numbers. I don't understand which is more helpful for a aircraft.

On a website I read this:

  If the Reynolds Number is large, the viscosity effect is small. For the for us practical values the inertia or density forces dominate, and the parasite drag increases with the square of the velocity. However, although the viscosity is unimportant, it may still affect the very thin boundary layer, leading to the creation of turbulent flow.
  Thus the importance of the Reynolds Number is that it tells us the type of flow we can expect. It tells you whether you can hope for having laminar flow over the wing and other parts of your airplane. A low Reynolds Number gives laminar flow while a high Reynolds Number gives turbulent flow. For both a laminar and a turbulent boundary layer increasing Reynolds Number gives lower skin friction drag. However, because of the higher energy loss in the boundary layer, a turbulent layer always has higher skin friction drag.

In this, there is something like this: For both a laminar and a turbulent boundary layer, increasing Reynolds Number gives lower skin friction drag. I didn't understand the meaning of that statement.

Is there a rule like "Higher Reynolds number, higher drag force"?

And what exactly do parasite drag and boundary layer do?
And what do their vastness or rarity contribute to?

Simply: how big should a Reynolds number be for an aircraft to be efficient?


texts: What are the empty weight and maximum takeoff weight of the Moller Skycar?

texts:
I know what are empty weight and MTOW, which are data I need for my school project. But the website for Moller Skycar only shows the gross weight and net payload: https://www.moller.com/moller_skycar400.html.
But in the wiki for the same vehicle, it shows that the empty weight is the gross weight and the MTOW is the gross weight + net payload: https://en.wikipedia.org/wiki/Moller_M400_Skycar.
Could you guys please help me figure out what is the correct value for the Moller Skycar 400?


texts: Are there benefits to opening a flight plan if I'm flying over populated areas?

texts: Here in Idaho we have a lot of mountains and desert areas where if I had to make an emergency landing or crashed it may take a very long time to find me. In that case I can see the benefit to opening a flight plan. But in areas where I'm flying over most or all populated areas, someone would see the crash well before they would start looking for me. In that case, are there other reasons to file and open a flight plan?


texts: Can a GA headset be used for listening to normal audio or with a cell phone?

texts:
I own an older but still nice noise-cancelling general aviation headset from Denali, with the two-plug adapter.

I wonder if I can/shall repurpose it.  For example, I now have to take a number of international flights, 14 hours as a sardine...  not fun.  Does a GA headset make for a good entertainment and silence headset?  Or, I could use the GA headset for phone calls from my Android cell phone.

Good idea / bad idea?


texts: What are the points 1864 and 1922 on this in-flight map?

texts:
This was taken in a Emirates flight Dubai-Paris in December 2015.

What are on these 2 locations?
Why these numbers? Are they dates?


texts: How do I calculate the impact of the winds aloft in this test question?

texts:
I was flying through this section in the ASA test prep book, I thought I had mastered this E6B.  But this has me stumped:

I can’t do the math to figure out how many knots I’ve traveled. But in the answer it has me plotting a course of 280 (100 + 180) from the departure point. I cannot figure out for the life of me where they got this course.
I see that the winds are from 100 in the winds aloft, but I can’t imagine how I get a 100+180 course from that.  I feel like I’ve missed some major concept.


texts: Why are airlines so concerned with checked baggage weight?

texts:
Why is it that commercial airlines are so concerned with checked baggage weight, such that they charge extra just for the privilege of checking in a suitcase with a limited weight (e.g. 15kg), and then if you should go even a couple of kg over the limit, they charge quite a bit per kg?

My first guess is they see it as a way of making extra money, but is this the only reason?

The reason I'm so puzzled about it is that they don't seem the least bit bothered about the weight of carry-on luggage, not to mention the passenger's weight (e.g. I weigh about 70kg more than my daughter, yet our ticket prices are the same). And then the weight of the aircraft itself - e.g. an Airbus A320 weighs 42.6t, with a max take-off weight of 78t according to Wikipedia. So why are they so concerned about an extra 3-4 kg in the checked-in luggage?


texts: What is meant by "fuel flow: on " in checklists?

texts:
What is mean by "fuel flow: on " in checklists? For example:

http://www.projectlear45.nl/docs/Checklist_LEAR45.pdf


texts: Is there any recorded instance of a passenger's hat or scarf being blown into an aircraft's engine?

texts:
Passengers climbing the stairs into an airliner are often subject to gusts of wind; I've had to hold onto my own scarf in the past.

It doesn't seem beyond the bounds of probability that a passenger's hat or scarf could be whipped off suddenly, to be deposited into a windmilling - or even idling - jet engine.

Has this ever happened?

I would imagine that the average hat or scarf would be better for an engine than a handful of good-luck coins.


texts:
The Jeppesen and FAA IFR plates represent the same information in different ways. The FAA publishes its charts for free, but the underlying data that goes into the charts (e.g., exact coordinates of fixes, frequencies, etc) doesn't appear to be published in a structured format. The PDF files that the FAA publishes appear to be created using Bentley MicroStation, but do not seem to embed any useful metadata about what the various symbols mean.

Based on that preliminary research, I am wondering how Jeppesen creates their various charts, such as IFR approach plates? Do they simply take the FAA charts and manually create their own derived charts (which strikes me as tedious and error-prone)? Or is there some hidden repository of structured FAA data available somewhere that they use to create them?


texts: What is an ATC clearance? Does a VFR flight have to get a ATC clearance?

texts:
1)
Do all flights have to get an ATC clearance to fly in controlled airspace such as class C airspace? I know that IFR and VFR flights are provided with ATC service in class C airspace, but I am not sure that receiving ATC service means an ATC clearance must be obtained. And if so, should VFR aircraft also get an ATC clearance like an IFR clearance that is given to a pilot before take-off including clearane limit, route, level, squwak, etc?

2)
What is an ATC clearance? 'ICAO Annex 11' defines an ATC clearance as an "Authorization for an aircraft to proceed under conditions specified by an air traffic control unit." And, also states that an "ATC clearance shall indicate a) aircraft identification as shown in the flight plan, b) clearance limit, c) route of flight, d) level(s) of flight for the entire route or part thereof and changes of levels if required and e) any necessary instructions or information on other matters such as approach or departure manoeuvres, communications and the time of expiry of the clearance."

I think it refers to the IFR clearance given to pilot before take-off.

Does it mean that an ATC clearance always includes all these items such as route or level? If the ATCO instructs a VFR pilot to maintain 5,000ft for separation with IFR, is it just instruction because it doesn't include a clearance limit and route?

In the same vein, is a take-off clearance a type of ATC clearance? It doesn't include some items such as route. But the definition of an ATC clearance states that "The abbreviated term “clearance” may be prefixed by the words “taxi,” “take-off,” “departure,” “en route,” “approach” or “landing” to indicate the particular portion of flight to which the air traffic control clearance relates."


texts: Where Can I Find the Master Minimum Equipment List for the A320 Series (UK / EUR)?

texts:
I'm currently trying to locate the Master Minimum equipment list for an Airbus 321.

I have the FAA (US) version of this document, but I'd like a copy of the UK or EUR version if possible.

The Master Minimum Equipment List page on CAA doesn't contain a link to the any airbus series

http://www.caa.co.uk/application.aspx?catid=33&pagetype=65&appid=11&mode=list&type=sercat&id=16

I found a page on the flight safety committee that contains 5 historical links to lists for the A320 series aircraft. But all of these links are dead.

http://www.ukfsc.co.uk/information/caa-notifications/275-caa-master-minimum-equipment-list-amendements-mmel

Can anyone point me in the right direction as to where I can find this document? I would prefer the revision that was current in September 2013 for UK and Europe.


texts: Does a Type Rating "upgrade" with your license?

texts:
I believe anything the FAA refers to as a "rating" upgrades automatically with your license. For example, if I get my instrument rating on my Private Pilot License, I don't have to retake the instrument checkride when I get my commercial license in order to fly IFR commercially. This is not true for license classes (single engine land, multi-engine land, single engine sea, multi-engine sea). If I get a private MEL, and then take my commercial checkride in a single engine, I still have to take another commercial MEL checkride in order to exercise commercial privileges in a multi-engine airplane.

The question is, do type ratings work like instrument ratings or like license classes, and what regulations govern this?


texts: How does an aircraft derive winds aloft on its own?

texts: The G1000 has a feature where it can put up a winds aloft arrow/speed in the PFD.  I've been sort of wondering how exactly this is determined.  My guess is that the aircraft (or the G1000) knows your airspeed via the pitot/static system and heading via the fluxgate/mag compass.  Then, it uses your GPS position to figure out where you should be every X seconds given the airspeed and heading.  Any difference must be attributable to winds aloft.  Does this make sense?


texts: Do airline pilots get to go home often to see their family and have a break from flying planes. If so, how many days?

texts: Do airline pilots get to go home to see their families often, and if so how long?


texts: What materials are used in a Rolls-Royce RB211-524 Engine?

texts:
I am trying to know what materials (Specifically metals) are used in making a Rolls-Royce RB211-524 Engine. I already found what is used in engines in general, but is it the same for all? And if so, what could be different in this specific engine?

Thanks!


texts: What may cause a strong smell of paint thinner like odor and no power to master in a Piper Warrior?

texts: I am sitting in the hangar with my Piper Warrior II sitting outside.  The battery is completely flat and the cabin smells like paint thinner.  This is the first time that this has occurred and if anyone has experienced this before please let me know what is going on!  This is a maintenance question and I am concerned leaving the plane in the current condition over night.  This is NOT a 100LL smell.


texts: What are the EASA external aircraft lighting requirements for day/night/VFR/IFR operations?

texts: I have attempted to decipher the EASA rules related to non-commercial small aircraft external lighting requirements (for a pilot) for the various types of flight, and I can only find the MEL for complex aircraft.  Can someone point me to the requirements?


texts: Does the air resistance of a jet engine air intake count towards the jet's total air resistance?

texts:
Does a jet engines air intake count to the overall jets geometry dependent air resistance?

Taking the Saab Tunnan as an example it's overall air resistance has to be quite low because of it's huge air inlet.

Or does the inlet create air resistance as well but just not so much?


texts: How do I find the serial number and other important information of an old airplane I have?

texts: My dad has passed away and I have his plane. I can't find the paper work but I want to get a replacement title from FAA. Their site says that I need manufacturer name, model designation, N-number, and serial number.  I have the N-number but don't know where to find the other info. Could you please help me find that information?


texts: Why are commercial flights not equipped with parachutes for the passengers?

texts: I understand that commercial flights are equipped with life vests. I also understand that most military jets are equipped with ejection seats. It may be costly and technically challenging to equip passenger planes with ejection seats. Having seen air-borne personnel lining up and parachuting out of a C130, what is preventing flights from equipping each passenger with a life-saving parachute? Is it very technically challenging for an untrained person to deploy a parachute, or are there other reasons?


texts: How to calculate "duty" when between flights in a 135 operation

texts:
Here is the scenario ... at 6:00am pilot flies from Location A to Location B to drop off a customer.  Flight duration is 2hrs.  Pilot is then given the day to do with as they want to but must be ready for the return flight at 22:00 later that day.  The return flight is another 2hrs.

Question: Has the pilot exceeded their daily duty limit under part 135 rules?  Or is it reasonable to assume the interval between flights would constitute a 10hr rest period?

NOTE: between the time of 8:00 and 22:00, the pilot was not paid and able to do anything they wanted with their time.  They were not expected to wait at the airport and knew they would not be needed before 22:00.


texts: When buying an aircraft which has had multiple owners it is acceptable to get the logbooks from the previous owner only?

texts: I know of a case where a small GA aircraft has had three owners since it was manufactured.  However the only airframe, power plant and propeller logbooks available for the airplane are from the most recent owner and no other logbooks are available from the two owners prior to the current owner.  The current owner's logs are good with the required annuals, engine overhauls, etc. documented and incorporates all FAA and manufacturer ADs to date.  Does this decrease the value of the aircraft?  My first thoughts are that yes, it will, as I have no idea as to what happened to the aircraft prior to the date the current owner obtained it, but I'm not totally sure.


texts: How did the De Havilland Mosquito compete with contemporary jets?

texts: During the Second World War, the British De Havilland Mosquito light bomber achieved success in raids through its sheer speed. Traveling at up to 392 mph, it could outrun virtually all piston-engined interceptors, removing the need for it to carry defensive weaponry. Later in the war though, German jets like the ME-262 could travel at speeds in excess of 500 mph, seemingly making the Mosquito obsolete. How did the Mosquito compete with these jets successfully, despite the obsolescence of its only major advantage?


texts:
In most weather reports I see "Outlook VFR" and I am not sure what that means and as a pilot what should I expect? What is an "outlook" and what does it mean when it is "VFR"?

In other words, what does 'OTLK... VFR' mean in weather reports?


texts: Why don’t airliners have temporary liveries?

texts: For buses, it’s quite common to have plastic foil with advertisements on them, but I’ve never seen that on an aircraft. Looking at how aggressively some airlines try to save money, they probably already came up with the idea to sell the space on the side of their aircraft for advertisement purposes – so why did they not do it? Is there any technical reason to not have temporary liveries?


texts: I was on a intercontinental flight to the US and noticed this object shaking with the wind and moving as the flaps change position. Is this normal? I have never seen this before. Is it safe to travel with this kind of item on the trailing edge?


texts: Clarification on autogyro thrust formula

texts:
I'm slightly confused regarding the formula quoted here:
How to calculate the amount of thrust of a autogyro during auto rotation?
When they say thrust is equal to the weight.  Do they mean use earth weight directly i.e. 50Kg or am I supposed to calculate thrust as weight force, i.e. F = m * g?
If its the latter can I just use summary of component forces to determine vertical thrust, resultant from a horizontal axis of travel?


texts:
I've travelled from Vancouver to London often enough to see this phenomenon as something that happens regularly enough to notice. I'm just not sure why.

So... the route from Vancouver to London is basically a series of right-hand turns. I guess it follows a set of rhumb lines or whatever. But what I noticed was that most right-turns are preceded by a smaller left turn.

ie the aircraft banks and turns left for a couple of seconds, then straightens up and goes straight into the longer right hand turn I'm expecting.

So my question is, why does it do that little turn in the opposite direction? I can't imagine it's navigational, not when it's cruising at high altitude. Is it something mechanical? Say to make sure everything is working and not iced up? I imagine the aircraft is on autopilot at that point, so it's not a pilot thing.

Does anyone know what this is? In fact, has anyone else even noticed this?! I think I've noticed it most on Vancouver-London because when you're over Iceland and the aircraft starts to turn north, you start to wonder where you are headed!


texts: Is there any benefit of using a swept wings at low-subsonic speeds?

texts:
Is there any benefit to using swept wings for speeds up to 250km/h ?
(By the way..Why do some fast birds like falcons, swifts and most migratory birds use swept wings or raked wingtips since they fly at low subsonic speeds?)
Peregrine falcon - swept wings

Alpine swift - swept wings

Albatros - straight wings with raked wingtips

Common swift - straight wings with raked wingtips


texts: Why don't modern fighter aircraft hide their engine exhaust?

texts:
In many photographs, the F-4's unique geometry hides one or both engines. I've been told that this is one of the terrific accidental features of the F-4, as it would help shield the hot exhaust from sensors used on heat-seeking missiles.
Is it true that the F-4 was harder to target with heat-seeking missiles due to the shape of the empennage? If so, then why don't modern aircraft use a similar design?
Example images:


texts: How much more efficient is an aircraft with no windows?

texts: How much more efficient is an aircraft with no windows (in terms of operation)? Consider the hypothetical situation where you have two aircraft identical in every way, except one of them has no passenger windows. Or is the difference so small that its negligible?


texts: After an emergency landing, what procedures should the pilot follow?

texts:
In case of an emergency landing (non-fatal) on a road/highway or in a large field, what happens next?

Should police be contacted?
Should aircraft owner and/or insurance be contacted?
In case landing is on a road or highway, what should the pilot do?
In case of landing on someone's personal property, what should one do?


texts: What is the aerodynamic reason that the An-225's vertical stabilizers are not simply vertical?

texts:
I am trying to understand the aerodynamic consideration that the two vertical stabilizers of this gigantic Antonov An-225 are not simply made vertical and are slightly pointing in. Then my questions are:

What is the reason?
What is the degree they lean?


texts: Did DB Cooper's aircraft land safely with the aft stairs open?

texts:
I've never seen a 727's aft stairs open, but presumably, based on an Wikipedia image and common sense, they do reach the ground when the aircraft is on the ground. Furthermore, (as I understand it), airliners land with a positive pitch, which means that assuming a level runway, the rear of the aircraft will touch down first. However, this suggests that if the aft stairs of the 727 were open during landing, they would impact the ground during landing and, given the pitch, do more than scrape the ground and cause damage to the aircraft.
However, DB Cooper's jump left the aft stairs open, and (as far as I can tell) it seems that the landing was uneventful besides the stress of having a hijacker potentially on board (although it's quite understandable if no one made any record of it, given there were slightly more important things to deal with).
If DB Cooper's flight did land without damage, why is that—did the 727's aft stairs not fully touch the ground? If the stairs did impact the ground, was there sufficient damage to require repairs?
(I meant this question to be more about the 727 than DB Cooper, but since his was the only landing with stairs open, there wasn't much room for speaking in general terms).