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Cobra Maneuver

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Re: Cobra Maneuver

#31

Post by bolasanibk »

onlyrealcuzzo wrote: post #29
hutzlibu wrote: post #12

Earlier quoted context omitted.

"And after your opponent overshoots--you just lost a ton of energy--and energy is everything in aerial combat. " The idea is, to be able to make the kill, after you are now behind. Then it does not matter, if you are too slow. But wikipedia indeed says, this manoever has never been confirmed in real air combat, so yes, its usefullness is quite limited.

Dumb question - why can't planes shoot in reverse? It seems like this would be useful for these situations. I get that it would be hard to aim - but can't computers do that?

Some have: B-29 tail turret https://media.defense.gov/2010/Jun/14/2000352211/-1/-1/0/100...

I am guessing mostly space and weight are at a premium in an airplane.

Re: Cobra Maneuver

#32

Post by leeoniya »

jleahy wrote: post #30
onlyrealcuzzo wrote: post #29

Earlier quoted context omitted.

Dumb question - why can't planes shoot in reverse? It seems like this would be useful for these situations. I get that it would be hard to aim - but can't computers do that?

Energy. If you fire a missile to your rear then it needs to first accelerate to your original speed just to be staying still, only then can it accelerate towards the target. An AIM-9X can do this, but the kill probability drops rapidly as you move off boresight.

> only then can it accelerate towards the target

but in a dogfight (where this move is presumably useful) the target is not stationary, it's moving towards the missile. if all the missile does is accelerate to stay still, it will still hit the target at 700mph

Re: Cobra Maneuver

#33

Post by bornfreddy »

jleahy wrote: post #30
onlyrealcuzzo wrote: post #29

Earlier quoted context omitted.

Dumb question - why can't planes shoot in reverse? It seems like this would be useful for these situations. I get that it would be hard to aim - but can't computers do that?

Energy. If you fire a missile to your rear then it needs to first accelerate to your original speed just to be staying still, only then can it accelerate towards the target. An AIM-9X can do this, but the kill probability drops rapidly as you move off boresight.

What about guns? Relative speed against the enemy is the same no matter if you shoot forward or backward. Or am I missing something?

Re: Cobra Maneuver

#34

Post by canjobear »

js2 wrote: post #14

> Super stall plagued the early years of Saab 35 service, causing several deaths, which led the Swedish air staff to implement extra training on how to counteract and recover from them. The result was the cobra maneuver. Necessity, the mother of invention.

Although in this case there's no evidence that it was a useful invention.

Re: Cobra Maneuver

#35

Post by gmiller123456 »

Is there a reason why modern planes can't shoot backwards? A lot of the WW2 planes had turrets a separate gunner would control, but they all seem to have disappeared.

My only guess is that dogfights don't actually happen much anymore.

Re: Cobra Maneuver

#36

Post by Maursault »

bornfreddy wrote: post #33
jleahy wrote: post #30

Earlier quoted context omitted.

Energy. If you fire a missile to your rear then it needs to first accelerate to your original speed just to be staying still, only then can it accelerate towards the target. An AIM-9X can do this, but the kill probability drops rapidly as you move off boresight.

What about guns? Relative speed against the enemy is the same no matter if you shoot forward or backward. Or am I missing something?

Bullets don't move at the speed of light.[1] Shoot a bullet backwards off a bullet train, that bullet's ground speed is less than if shot from the ground while stationary. Similarly, shoot a bullet forward off a bullet train, that bullet's ground speed is more than if shot from the ground from a stationary position. Shoot bullets backwards off a jet moving Mach 3 (just sayin') those 1700mph bullets will still be moving in the forward direction of the jet at 600mph relative to the ground.

[1] They should use rear-facing lasers!

Re: Cobra Maneuver

#37

Post by meheleventyone »

hutzlibu wrote: post #12
hatsunearu wrote: post #10

Unfortunately the circumstances where this is useful is very limited. You'd have to be in very close range and in a very bad disadvantage, which honestly doesn't last long (you'd blow up very fast) and when you start decelerating you become a very easy target to hit. And after your opponent overshoots--you just lost a ton of energy--and energy is everything in aerial combat. Energy is the currency you spend to maneuv…

"And after your opponent overshoots--you just lost a ton of energy--and energy is everything in aerial combat. " The idea is, to be able to make the kill, after you are now behind. Then it does not matter, if you are too slow. But wikipedia indeed says, this manoever has never been confirmed in real air combat, so yes, its usefullness is quite limited.

> The idea is, to be able to make the kill, after you are now behind. Then it does not matter, if you are too slow.

Air combat is rarely 1vs1 so being slow means you get killed by someone else.

Re: Cobra Maneuver

#38

Post by somerandomqaguy »

akkartik wrote: post #4

Is this the maneuver John Boyd used to use? https://www.youtube.com/watch?v=p55LY30AIoc

I don't think so. The way I'm reading it, both fighters should be in a turn fight with the opponent closely following Boyd's rear at high speed.

In the case of a flat plane, you're dumping airspeed but you don't stall the aircraft. This guy explains it way better then I can, describing the maneuver as a Rudder Reversal: https://www.youtube.com/watch?v=5ab6Ek1UCcM. Skip to 2:07 to see him demonstrate it with model airplanes.

The Cobra you do enter into a stall (the airflow departs the top surface of the wings) and are instead relying on other some other aspect of the plane to control the aircraft and get the plane back into the fight.

Note that this is just what I know from superficial memory, I never studied it in depth.

Re: Cobra Maneuver

#39

Post by chrisseaton »

gmiller123456 wrote: post #35

Is there a reason why modern planes can't shoot backwards? A lot of the WW2 planes had turrets a separate gunner would control, but they all seem to have disappeared. My only guess is that dogfights don't actually happen much anymore.

To put a gun in a turret it's got to be pretty small. Turret guns were therefore only good for shooting at slow, close aircraft. You basically don't get that anymore.

Re: Cobra Maneuver

#40

Post by googlryas »

gmiller123456 wrote: post #35

Is there a reason why modern planes can't shoot backwards? A lot of the WW2 planes had turrets a separate gunner would control, but they all seem to have disappeared. My only guess is that dogfights don't actually happen much anymore.

This is correct. It's actually rare for pilots to even see the planes they're attacking, if they're attacking a plane at all.
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