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Aircraft performance covers areas such as the amount of runway required to takeoff or land and how fast an airplane can climb or descend.
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Is a winglet better than an equal span extension?
Is there indisputable evidence that a winglet improves performance over an equal span extension? Please note: I am only interested in L/D improvements.
Winglets do improve roll performance, that is ...
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Can the Airbus A380 safely fly with two engines out on the same wing?
I know twin-engine jets can safely take off and fly with one engine out (i.e. all thrust only on one side). Of course quad-engine jets are also able to fly safely in case one engine is out.
But is ...
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Why would a glider have water ballast? If it is trying to stay aloft without an engine, wouldn't it be better to be as light as possible?
So I was looking at the description of a ASW 27 B glider and ran across this statement:
Two water tanks in the wing plus a further 35 liter tank in the
fuselage enable the ASW 27 B to carry more ...
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Do airplanes need brakes in the air?
A few days ago I flew on a Boeing 737-900ER. Luckily I was sitting just beside the left wing, seat 26B. I observed that the spoilers were activated (opened) just after the pilot spoke on the Passenger ...
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Is it possible for an SU-25 to fly high enough to shoot down a Boeing 777?
A common theory from pro-Russian netizens surrounding the MH-17 tragedy is that it was a Ukrainian Sukhoi SU-25 ground attack plane that shot down the civilian airliner. However, the MH-17 was flying ...
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Why was the boat mounted this way on the underside of the wing on the "Landseaire" flying yacht?
After seeing the below image of the "Landseaire" flying yacht here I was curious to know why the small boat mounted to the underside of the plane was mounted the way it was. At least to me (and @Dave ...
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What do winglets do to increase aircraft performance?
It seems like a lot of the newer airliners have winglets or wing fences. How do they improve aircraft performance?
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Do the Mt. Everest rescue helicopters have modified engines to operate at high altitudes?
There are so many climbers on Mt. Everest today that there is now a helicopter rescue service there. They operate rescue up to 21,000 + ft. Because this is essentially stationary service it seems that ...
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What happens if you exceed the maximum speed on a C172?
The airspeed indicator has a red marking that means: "never exceed this speed" ($V_{NE}$, around 160 KIAS). Why can't you exceed that speed?
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What are the effects of the Boeing 787's very flexible wings?
I recently came across this picture of the Boeing 787 series aircraft's incredible wingflex:
I suppose this is a consequence of using very light CFRP wings, but how does the wingflex itself improve ...
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Why are dirt and bugs on an aircraft so bad?
It's noted in many POHs to keep your aircraft clean all the time, but is there a reason to this? Dirt hardly add any sort of weight to the aircraft, bugs are extremely small and other things such as ...
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What is the operating altitude of jetliners?
I am performing a science project, and this involves knowing the average operating altitude at which commercial passenger airplanes (jetliners) fly.
I am trying to find minimum operating altitudes and ...
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How does the mounting location of a jet engine affect aircraft performance?
Different jet airplanes mount the engines in different ways.
For example:
Under the wing
To the fuselage
How does the engine location affect aircraft performance? Is one better than the other?
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Why are jet aircraft never designed with a slower cruise speed?
All jet airliners have a cruise speed between Mach 0.82 and Mach 0.85.
At those speeds the aircraft are flying at their maximum subsonic speed. Any greater cruise speed would only be ...
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In WW2 aircraft, where were gun cameras mounted, and did they suffer performance penalties?
During WW2, some aircraft had gun cameras that activated whenever the guns fired, so that people on the ground could evaluate performance and help with kill ratios and other statistics. These were ...
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