What would be the effect if all the passengers on <say> a 747 aircrat in flight, all jumped up at once?

Question

Would the aircraft become lighter and climb for example?

spotted the typo - aircraft

I ask out of curiosity - often wondered whether the effect would be noticeable i.e. the weight of the aircraft vs. the passengers etc

Note: I don't mean jump out! I just mean jumped up in the aisles/seats all at once

Hi Mike S - can you elaborate; really struggle with this. If I had a boulder in a box (sealed container), surely it would weigh less if the boulder managed to levitate (i.e. lost contact with the floor thus exerting no force?)

Answer 1

It would have an effect on the plane because the plane would become lighter for just a second, however the effect would not be felt because they would not be in the air long enough. If they were off the floor long enough then the nose of the plane would start to gradually pitch up and you would enter a slow climb. The weight and speed of the plane determine the angle of attack, or pitch attitude, the plane must maintain to hold level flight. If the plane was holding level flight and the speed was not adjusted the plane would start to climb because it had a higher angle of attack than it needed. However it would not have time to go through all that because the passengers would only be off the ground for a second. The thing you would have to worry about it when they came back down. Everyone would increase the force on the aircraft for a split second which could (Although I doubt) increase the planes weight to beyond its capability which would make the wings snap off. Its the same thing that happened to a tanker putting water on a forest fire a few years ago. He was dumping the water then pulled up before all the water was out. The extra weight was too much stress on the wings which snapped off. He was supposed to lose all the water before performing that manuever. I have included the video to show what would happen if it did go over it's limit.

Answer 2

Yes. The same effect occurs when the pilot dumps fuel in the even that an engine goes out. The loss of weight cause the plane to require less forward velocity to keep the lift on the wings. The less fuel a plane has, the slower it uses it, to a certain extent. The large amount of passengers on a 747 would be a very significant weight for the plane. If they were to all jump at once, the plane would probably lift very quickly, just before the pilot would be able to correct the airspeed and flaps.

Why do you ask?

Answer 3

Nothing would happen because the aircraft is a sealed container.

The same applies to a sealed truck containing say budgerigars. If the birds were flying around inside the sealed truck the truck would weigh the same if the birds were all on their perches.

If the truck housing had small holes the truck would be heavier when the birds were perched.

Answer 4

i reckon so yes because its still a few tonne lighter for like a second....id be more inclined to ask would the place shake around loads when everyone hits the floor again? would it fall?

Answer 5

They would all land at once - give or take a millisecond - still in the plane which would still be flying normally.

Answer 6

Same as if all people in world jumped !
Nothing

Answer 7

The would die if the plane was in the air.

Answer 8

No doubt the flight attendant would have something to say about this! Like "ladies and gentlemen, please would you ALL sit down"...

Answer 9

The stewards would get angry

Answer 10

MY MOM WOULD MAKE A HOLE IN THE PLANE