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1500 questions
45
votes
6 answers
Why is water-contaminated fuel bad, but water-injection is not?
A "wet" takeoff of a KC-135 with J57 engines—By USAF Photographer (USAF photo) [Public domain], via Wikimedia Commons
Why is water-contaminated fuel bad, but water-injection is not?
The way I understand it, water-injection lowers the combustion…
user14897
45
votes
6 answers
When are aircraft required to dump fuel for emergency landings?
I've heard that in a lot of instances a jet that is making an emergency landing is required to dump excess fuel. In a lot of instances this would make a lot of sense. For example, if the gear cannot be lowered and the plane must land on its belly.…
Jae Carr
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45
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3 answers
Why do many fighter jets have double vertical stabilizers?
Many fighter jets have double vertical stabilizers, e.g. F-14, F-15, F/A-18, F-22:
On the contrary, most general aviation planes and commercial airliners do not. While there are certainly exceptions in both categories, I think it is fair to say…
kevin
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45
votes
12 answers
Why don't all commercial aircraft transmit GPS data in real time?
It seems strange that trucks and taxis can be set up to transmit GPS data in real time but aircraft cannot. Wouldn't this be a useful function and feasible to implement?
JoelFan
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45
votes
8 answers
Why aren't cell phones allowed to be used in aircraft?
What problems do cell phones cause? How is using a cell phone in the air different than using it from the ground?
flyingfisch
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45
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2 answers
Is the visual artifact seen over the wing from different air densities, a reflection or something else?
I have noticed a strange visual artifact over the wing of a Boeing yesterday. You can see two manifestations of the artifact in the pictures below.
The first shows it at the front edge of the wing. There were actually many of those, but I only…
Lukas_Skywalker
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2 answers
If I own land, can I create a private runway on my property for my own use?
In the United States, if I own land that has an area suitable for landing a small general aviation airplane, can I just create a private runway, or do I have to officially be registered with the FAA or some government agency?
Canuk
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45
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3 answers
What are the spiral marks in the center of the engines?
When I get a chance to peek inside an engine, I noticed that many have spiral marks painted in the center. What is the purpose of these?
Pictures:
Farhan
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44
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10 answers
Is it possible to recover from a flat spin?
In Top Gun, Maverick's F-14 enters a flat spin after flying through another F-14's jetwash, forcing him to eject and causing the death of Goose.
Is this scenario possible or was it only created for theatrical purposes?
If not, how does it happen,…
flyingfisch
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44
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2 answers
What does it mean when the controller uses the word "request"?
I recently had the opportunity to fly a PAR approach into Büchel Airbase in Germany. It was a ton of fun and I'll definitely try it again when I get the chance. However, as we were getting set up for the approach I received the following…
falstro
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43
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5 answers
How common are cancelled landing attempts?
I recently traveled from Stansted, UK to Skavsta, Sweden with Ryanair, and was informed that depending on the weather (it was very foggy), we might end up landing at Arlanda (~150 km from Skavsta) instead.
The pilot later decided to try landing,…
Mårten
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43
votes
5 answers
What does "Information " in ATC transmissions mean?
When listening to ATC broadcasting (at least for ULLI), phrase "Information on board" may be heard. Charlie, India, Whiskey, etc. refer to "C", "I", "W" but what do these codes mean? What kind of information is this?
HUB
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43
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6 answers
What does it take to maintain a private pilot certificate?
What, if any, requirements are there to maintain a private pilot certificate? For example:
Do I have to renew my certificate after a period of time? E.g. annually, 5 years, 10 years
Do I have to receive a minimum number of continued training…
tehDorf
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43
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2 answers
What is this quad-jet plane at El Paso Airport?
If you look at El Paso International Airport on Google Maps, on the south side apron and across from a hangar that is labeled "Sierra West Airlines" (west of the NASA facilities) there is a small quad-jet plane:
The aircraft is about 20 m long and…
William Taft
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43
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4 answers
Why do flight control cables not slacken during the cold temperatures at cruise?
Image source
Flight controls in airliners have long cable lengths in between the cockpit controls and the control surfaces. For instance in the picture above: the pilot operates the yoke, which deflects a steel cable running through the front…
Koyovis
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