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paddy-boy66
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Can anybody tell me how aircraft fly up side down? I'm an under grad aero student and can't see how aircraft do. Can any aircraft theoretically fly up side down?
You just need to adjust the angle of attack (http://en.wikipedia.org/wiki/Angle_of_attack)paddy-boy66 said:Can anybody tell me how aircraft fly up side down? I'm an under grad aero student and can't see how aircraft do. Can any aircraft theoretically fly up side down?
No, you've fallen prey to the most pervasive fallacy in aerodynamics - the Equal Transit Time fairy tale. Google that phrase, and you'll find many places that show how it's wrong.paddy-boy66 said:but doesn't the resultant lift always act in one direction relative to the "upper" surface so if its upside down won't the "lift" be downwards? Am i being stupid in saying this?
Well considering that some aircraft fly upside down, it is actual rather than theoretical. Practially, it is limited to small aircaft, acrobatic and jet fighters, and the like.paddy-boy66 said:Can any aircraft theoretically fly up side down?
Do you also have a crash-team sim?Averagesupernova said:Hmmmmmmmmm. I'll have to try that with a 747 on my flight sim.
I think, perhaps, by "any", he meant every. Though pretty much any *airfoil* is capable of producing negative lift (or positive lift while inverted), many *planes* cannot fly inverted for various other reasons (structural, fuel flow, lift/drag ratio, etc).Astronuc said:Well considering that some aircraft fly upside down, it is actual rather than theoretical.
paddy-boy66 said:so then how do aircraft fly perpendicular to the ground, or is there a component of the thrust equal to g?
I don't want to get too much into semantecs, but since it was a 1g, transient maneuver, I don't know that I'd call that "flying upside-down".cyrusabdollahi said:You want to fly an airliner upside down, sure here it is:
If done properly, the forces are not a problem, nothing would be ripped off.
It's called a chandelle and it's a 1g manuver. If your airplane is going to fall appart at 1g, you have bigger problems.
russ_watters said:I don't want to get too much into semantecs, but since it was a 1g, transient maneuver, I don't know that I'd call that "flying upside-down".
It is possible for an aircraft to fly upside down due to the principle of lift. The wings of an aircraft are designed with a curved shape on top and a flatter shape on the bottom. When air flows over the wing, it creates an area of low pressure above the wing and high pressure below the wing. This difference in pressure creates lift, allowing the aircraft to stay in the air even when inverted.
Yes, pilots do have to make some adjustments when flying an aircraft upside down. They may need to apply negative G-forces to prevent themselves from blacking out and also use different control inputs to maintain stability. Additionally, some aircraft may have inverted fuel and oil systems to ensure the engine continues to run properly.
No, not all types of aircraft are capable of flying upside down. The ability to fly inverted depends on the design and aerodynamics of the aircraft. Some aircraft, like stunt planes, are specifically designed for aerobatic maneuvers and have symmetrical wings that allow for inverted flight. Others, like commercial airliners, are not designed for inverted flight and attempting it could be dangerous.
The length of time an aircraft can fly upside down depends on the type of aircraft and the skill of the pilot. Some aircraft, like stunt planes, are designed for extended inverted flight and can stay upside down for several minutes. However, most aircraft are not designed for prolonged inverted flight and may experience engine problems or loss of control if attempted for too long.
Flying an aircraft upside down can be safe when done by a skilled pilot in a properly designed aircraft. However, it is still a risky maneuver and should only be attempted by trained professionals. The G-forces and control inputs required for inverted flight can be physically and mentally demanding, and any mistakes could result in loss of control and a potential crash. Safety should always be the top priority when performing aerobatic maneuvers.