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Cobra Maneuver

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Re: Cobra Maneuver

#81

Post by trevorishere »

bazillion wrote: post #20
funstuff007 wrote: post #2

Didn't Maverick pull this off in Top Gun?

In Top Gun 2, he uses it twice. Once, during the training dogfight where Rooster has a chance to shoot him down (he says, "Too late, you had your chance" and then pulls off the maneuver, targeting Rooster instead afterwards). After the training dogfight, he is told by Cyclone, "...and I don't ever want to see that Cobra shit again. That could have gotten you both killed". The second time was towards the end when they…

> flares

Which do nothing for radar-guided SAMs... but pumping out chaff wouldn't be very visually impressive (if you could see it at all).

And of course, the strike package would have been accompanied by the EA-18G Growler to jam SAM radar.

Re: Cobra Maneuver

#83

Post by kortex »

nine_k wrote: post #78
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…

I always thought that the cobra is about making a radar lose the lock on you, because you suddenly stopped moving. Might be useful if you detect a radar pulse. Losing your speed and showing your belly / back to the enemy, when you cannot shoot, never looked like a reasonable thing to do.

Interesting. I don't work in defense / aero, but that seems plausible. Stealth aircraft are optimized to reduce cross section from certain perspectives. Front, bottom, and oblique are pretty good, iirc, while rear and side are harder to optimize. Not sure about top. I would think it would reflect most energy away from tracking radar unless an active seeker was coming in from higher altitude (in which case you are already toast).

Combined with some sort of chaff/decoy release, I could see this causing the seeker's kalman filter or whatnot choosing to go after the return which stayed on the same trajectory with the same signature.

Without a decoy, or with smart enough seekers (eg combined mm wave with IR), I think you are probably still going to be hit.

Re: Cobra Maneuver

#87

Post by Karellen »

pishpash wrote: post #44
leeoniya wrote: post #32

Earlier quoted context omitted.

> 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

In a vacuum. The aerodynamics aren't possibly the same.

Surely the aerodynamics are better for firing a missile backwards.

If you fire it forwards, the missile has to accelerate through whatever air resistance you're both already experiencing through even more air resistance to get to the target. That's hard.

If you fire backwards, the missile uses air resistance to accelerate towards (i.e. slow down) towards the target. Even when it goes through 0mph relative to the air and continues to accelerate, the resistance will be much less as it approaches an even higher closing velocity in a shorter period of time.

Re: Cobra Maneuver

#88

Post by giantrobot »

nine_k wrote: post #78
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…

I always thought that the cobra is about making a radar lose the lock on you, because you suddenly stopped moving. Might be useful if you detect a radar pulse. Losing your speed and showing your belly / back to the enemy, when you cannot shoot, never looked like a reasonable thing to do.

Not only do you lose speed but the attacker just needs to rake across your now giant profile with guns. They might also pop off a heat seeking missile which sees you as a giant hot spot against the cold sky.

Re: Cobra Maneuver

#89

Post by greedo »

nine_k wrote: post #78
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…

I always thought that the cobra is about making a radar lose the lock on you, because you suddenly stopped moving. Might be useful if you detect a radar pulse. Losing your speed and showing your belly / back to the enemy, when you cannot shoot, never looked like a reasonable thing to do.

You can use the Cobra to break a radar lock since most modern radars look for Doppler shift. But eventually the radar would pick you up again.

Re: Cobra Maneuver

#90

Post by giantrobot »

ninkendo wrote: post #77
TylerE wrote: post #70

Earlier quoted context omitted.

Fighter guns are fixed. You aim by pointing the whole airframe.

I think the operative question is, why must the guns be fixed? Wouldn’t it be useful for guns to be on turrets that can aim in other directions? We do it with helicopters (complete with automated aiming), and we used do it with bombers in WW2, after all. I’m sure the answer has to do with aerodynamics, and the general rarity of close-range dogfighting in the first place, that make such a design impractical.

> I’m sure the answer has to do with aerodynamics

It's both aerodynamics and mass. The main guns on most western fighters is the M61 Vulcan which is a 20mm rotary gun. The F-35 mounts a 25mm GAU-12 rotary gun. These are both pretty big guns and are typically mounted internally on the jet. Trying to fit one in a turret would not be practical, it would have tons of drag. In order to be able to rotate and elevate the gun it would need a lot of heavy duty motors to be able to actuate at fighter jet speeds.

Even if such a thing nominally worked, that space and mass could go to missiles. Missiles are far more likely to be used than some gun turret. A bore sight mounted canon is far more useful since the pilot is already going to be pointing the whole plane.

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