# Fast Airbrakes (1 Viewer)

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#### Ronhrin

let's assume that it's possible to maintain a object floating in the air, when we acelerate with the object there's basicly only one way to stop it, airbrakes.

let's assume that same object is traveling at a speed of 300 Km/h, is it possible to build a airbrake system able to fully stop the object in less than 1.5 seconds?

#### Averagesupernova

Gold Member
Hmmmmm. That would be a new definition of airbrakes to me. Airbrakes are typically used on trucks. What you are describing would be thrusters if I am understanding your post correctly.

#### NoTime

Homework Helper
Gliders (and other aircraft) use airbrakes.
Quite effective at high speeds, but they loose effectiveness as the speed decreases.
So bringing something to a complete stop seems unlikely.

For your purposes a parachute might be considered an airbrake.

#### brewnog

Gold Member
No, you won't bring it to a complete stop using air brakes. Look up the formula for aerodynamic drag, and you'll see why.

#### Mech_Engineer

Gold Member
Ronhrin said:
let's assume that it's possible to maintain a object floating in the air, when we acelerate with the object there's basicly only one way to stop it, airbrakes.

let's assume that same object is traveling at a speed of 300 Km/h, is it possible to build a airbrake system able to fully stop the object in less than 1.5 seconds?
There's no way you'll be able to get an object to stop that fast (5.66g continuous for 1.5 seconds) using just an airbrake, for the reasons stated above (most importatly the loss of decelerating force with speed.) Maybe retro-rockets?

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