Unanswered Questions
1,339 questions with no upvoted or accepted answers
18
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0
answers
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What causes the "dead band" phenomenon during takeoff on the Boeing 737?
During takeoff, the Boeing 737 encounters a distinctive "dead band" phenomenon after the initial pitch reaches approximately 10 degrees. Essentially, a slight increase in back pressure is ...
14
votes
1
answer
1k
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Is there a good source for estimating the per unit cost breakdown for a classic GA plane like the Cessna 172?
For instance, on a Cessna 172 what percent is spent on:
Raw materials
Labor actually manufacturing the plane
Testing the completed individual planes
R&D Making the plane (at this point, very ...
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12
votes
3
answers
1k
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Do aircraft using only spoilerons for roll control, with no conventional ailerons, have a crossover airspeed?
Airplanes generally have a crossover airspeed (a minimum airspeed below which directional control of the airplane cannot be maintained in the event of a rudder hardover). This is because, as airspeed ...
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11
votes
0
answers
412
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Who is this flyer seen in Oakland c. 1929?
Looking for identification of the man on the left. Second from left is W.A. "Sandy" Sanders, third is Denny Wright, and fourth is Clyde Sunderland.
Oakland, around 1929.
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10
votes
0
answers
236
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Are there any analyses of GA tie-down failures?
After a big harbor storm, there are frequently analyses of why boats break free of their moorings. This information is used to improve upon best practices, resulting in fewer boats breaking free and ...
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10
votes
2
answers
793
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Do constant maximum lift to drag ratio variable pitch propeller exist?
Are there variable pitch propellers, where pitch is set so that the blades constantly are at their maximum lift to drag ratio AoA, whatever the incoming relative wind speed & direction?
Such a ...
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9
votes
0
answers
278
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How to interpret flight schedule data from before 1987
I'm trying to interpret schedule data from before 1987 (see example).
Example line:
...
9
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0
answers
806
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How did Soapy get to fly Hornets?
Allegedly, in early June 1983, while flying a Sea Harrier during a NATO exercise off the coast of Portugal, Royal Navy's Sub-Lieutenant Ian "Soapy" Watson found himself in a rather ...
9
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0
answers
726
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How can I convert a frozen ATPL from South Africa to an Iranian one?
I have got a frozen ATPL license from South Africa and I'm from Iran. I came back home last year and I have converted my CPL/IR license to the Iranian piloting license by doing Air Law and Human ...
7
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0
answers
132
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What older regulations and exemptions does Boeing's 737 line benefit from?
Boeing is occasionally accused in the press of keeping the 737 competitive by being able to avoid newer regulations and standards, either through being previously certified or by other means.
The ...
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7
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0
answers
205
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Can a non-US registered aircraft be based in the US?
I am a Swiss citizen and I might have to move to the US for a couple of years. I own a small plane in Switzerland (HB-registered) and I'd like to take it with me to the US. As my stay in the US would ...
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7
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3
answers
801
views
Who was the first person to break the sound barrier?
In this video on Wikipedia of Chuck Yeager breaking the sound barrier in the Bell X-1 in level flight, at 2:44 the narrator says "For the first time, except in dive, a man has flown an airplane ...
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7
votes
0
answers
607
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Boeing 737-800 Source Off Light and Flight Director Bias Out Of View Function
I have seen the following occur during simulator events. With a left Source Off light illuminated and the captain's autopilot and autothrottles engaged (or re-engaged):
Captain's flight director ...
6
votes
0
answers
399
views
Why do the spoilers on the 737 only deploy to the flight detent after a flaps up landing?
Following an all flaps up (no flap) landing, the SPEED BRAKE
lever will not move beyond the FLIGHT DETENT and the spoilers
will not fully deploy (for reference this is stated in the Fcom 9.20.14 rev ...
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6
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0
answers
471
views
Engine Bearings Damage in Radial Engines
Studying the P47's dive performance in DCS, I noticed how it's easy to damage the engine bearings if you windmill the prop at high speed.
Doing some research, I discovered that all radial engines are ...
- 319
6
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0
answers
451
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What does the A340's underwing bulge (plastron) look like?
From Wikipedia:
From the start, engineers noticed that the wings were not stiff enough to carry the outboard engines at cruising speed without warping and fluttering. To alleviate this, an ...
CommunityBot
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5
votes
0
answers
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How do Antishock Bodies / Cuchemann Carrots delay shock-induced flow separation?
There are several online resources that describe these aerodynamic devices as either "Antishock Bodies" or "Kuchemann Carrots" and that they are used to produce some combination of ...
5
votes
0
answers
249
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How was the lost F35 from the Queen Elizabeth recovered?
In 2021, an F35 Lightning II from the Royal Navy carrier Queen Elizabeth crashed into the sea on take-off.
It was later reported that the aircraft was recovered from a mile below the Mediterranean.
...
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5
votes
0
answers
556
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Why do all trend vectors in the G1000 on airplanes indicate the status 6 seconds later? Why 6? Why not 5 or 10?
Why do all trend vectors in the G1000 on airplanes indicate the status 6 seconds later? Why 6? Why not 5 or 10? The fact that the trend vector shows after 6 seconds allows us to turn 3 degrees per ...
- 2,217
5
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0
answers
332
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Why is this placard on a Boeing 737 NG?
I was working on the cockpit of a Boeing 737 and was intrigued when I saw this placard. From what I know this has to do with Citibank being a lender or something along those lines.
Why would this be ...
- 323
5
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0
answers
106
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How dangerous (or not) are some synthetic types of aviation hydraulic fluids based on organophosphates?
Insider's January 13, 2023 Gerard Butler says he mistakenly rubbed acid all over his face while filming 'Plane' and didn't realize until he was 'burning alive' links to the Late Night with Seth Meyers ...
- 6,028
5
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0
answers
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Why isn't Yamaha EPeX300Ti more popular in aviation?
The answer to this question might be obvious to experienced aviators. But as an armchair enthusiast, I really couldn't find a satisfactory answer anywhere on the internet.
Below two pages came from ...
- 12.1k
5
votes
1
answer
359
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Where does the FAA define the dimensions of Terminal Radar Service Area (TRSA) airspace?
The airspace over the United States is classified into various areas of "alphabet" airspace (A, B, C, D, E, G). This is known as "regulatory" or "rulemaking" airspace ...
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5
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0
answers
418
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When did FedEx acquire it's current callsign and airline ID's?
FedEx currently uses the callsign "FedEx" and has the IATA and ICAO ID's of FX and FDX respectively.
Back in the 1990's they used the callsign "Express" and the IATA code was FM. (...
- 28.6k
5
votes
0
answers
504
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Why is the F-104 Starfighter’s afterburner thrust not greatly impacted by altitude?
Here is a page from the F-104 flight manual. It shows the flight envelope for the F-104 Starfighter with the powerful J79-GE-19 turbojet engine:
I have a question regarding the shape of the ...
- 28.4k
5
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0
answers
392
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How did the Blackops 'quiet one' helicopter muffler work?
Back in the Vietnam War era, special ops needed a quiet means of inserting soldiers behind enemy lines to install eavesdropping equipment. They modified a Hughes 500 to do the job. One of the things ...
- 20.8k
5
votes
1
answer
1k
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Were RCS tests performed on the ATF YF-22/YF-23 prototypes?
I know that radar cross section (RCS) tests were performed on geometric models of both the YF-22 and the YF-23 prototypes submitted for the Advanced Tactical Fighter (ATF) competition, but were the ...
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5
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0
answers
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Can I buy a A320 FCOM, FCTM and QRG as non-pilot?
I am very interested in the Airbus Systems. I really like the FCOM of the A320, there are some of them on the internet.
However, I like holding physical books in my hands more, than reading them on a ...
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5
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0
answers
294
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How is the required motor power calculated for a quadcopter?
I've been trying to find the required motor power for a quadcopter. I first calculated drag power and then I made a linear trend line for motor power against motor weight. I made the motor power 1.5 ...
- 19
5
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0
answers
255
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Why is this G-AIRMET's valid time earlier than its issued time?
For this G-AIRMET map, why is the valid time earlier than the time it was issued?
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