F-22 / F-35 5th Generation jets | News & Discussions.

SQ8 · Jan 1, 2015

Peter C said:
Just "180" rounds....

Isn't 150 the "usual amount". For instance on a Mig29? Su30?

Calibre also matters I guess. 25mm rounds having more accuracy due to higher velocity.. the same goes for the GSH-30 on the Russian hardware.. apparently its accuracy made the Russians limit the number of rounds.

gambit · Jan 2, 2015

Oscar said:
Calibre also matters I guess. 25mm rounds having more accuracy due to higher velocity.. the same goes for the GSH-30 on the Russian hardware.. apparently its accuracy made the Russians limit the number of rounds.

Am going to pose this only as speculation and an intellectual exercise.

But first...Why do we want high cyclic rate of fire, especially at moving targets ? Simply put, we suck at guesstimating where this moving target is going to be. It does not matter if the target is an aircraft in 3D space, or a deer running on the ground. It takes training, time, and often innate skill to make an excellent marksman. In gunnery, leading the target is always a learned skill, not something one is borned with. We attempt to quantify every aspects of this skill and continually refine it, whether it is to teach the human soldiers or impart it to the machines. So the reason we want a high cyclic rate of fire is because we want to deposit as much materials on the target as possible within a certain time frame, preferably as short a time frame as possible as well.

What if, for speculation's sake, the F-35's gunnery software is capable of this skill and does it at a high level due to the sophistication of the aircraft's sensor package ?

The sensors, active and passive, sees the enemy fighter ahead and calculate, with less than one meter precision, speculatively speaking, where the enemy fighter is going to be. The gunnery software calculate that based upon the target's predicted path, the gun will need to expend 10 rounds -- as a packet of material -- at that predicted spatial location. The F-35 pilot does have the option of shooting more than 10 rounds, of course, but he chose to let the gunnery software control the amount of munition. All he has to do is make the final decision to kill, which means to squeeze the trigger.

Say that out of 10 rounds, only four hit the target. But now the enemy fighter is damaged to one engine. Since the enemy fighter have widely spaced engine placement, he now have asymmetric thrust, which strains his flight controls in trying to keep stable flight. Damage to one engine also mean diminished hydraulics, which may lead to limited maneuverability.

As the enemy fighter struggles with its wound, the F-35's gunnery software now predict another 10 rounds, and the pilot shoots. Since the enemy fighter is already limited in maneuverability, 8 out of 10 rounds impacted.

The WW II era Japanese Zero fighter have two 20 mm cannnons. The American fighters heavily favored the .50 cal machine guns.

MK 108 cannon - Wikipedia, the free encyclopedia

...excellent 20 mm MG 151/20 required an average of 25 hits to down a B-17.

For our speculative air combat between an F-35 and an enemy jet fighter, 12 rounds of 25 mm cannon gunfire should be enough to at least send the enemy fighter home, if not outright compels the enemy pilot to eject, thereby denying the enemy a valuable combat asset.

Again, am not saying that is how the F-35's gunnery software works. Am just tossing a speculation out and let people make up their minds.

SQ8 · Jan 2, 2015

gambit said:
Again, am not saying that is how the F-35's gunnery software works. Am just tossing a speculation out and let people make up their minds.

Well, apparently the F-35 cannon has dispersion(average variance of actual round impact from aimpoint) that is less than most of its counterparts. This may be due to higher round velocity or canon design. Regardless, the short story is that the GAU-22 is going to have its rounds hit where the pilot aims with a much higher probability than say that of the venerable M-61. Add to that the larger caliber of the 25mm round vs the 20mm on the M-61.. and it becomes clear why the supposedly low number of rounds is actually enough(although a greater ammo capacity would surely be missed for strafing attacks if those ever come about).

Im sure that in the future the F-35 could incorporate an upgrade like one that was planned for the Eurofighter.. which basically ensures that the canon is only fired if the PIP comes directly over the target to ensure that every round hits. And while the Eurofighter does so via a radar lock to get accurate range and bearing.. the F-35 will have the added benefit of EOTS(which should in my view be able to track cannon rounds) to provide an even more accurate gun system.

The Speaker · Jan 3, 2015

Correct me if i am wrong but isn't stealth useless in close range as they are detected by then, so why are F35 and F22 armed with cannons? Wouldn't their engagements be limited to long range where cannons are useless.

Hamartia Antidote · Jan 3, 2015

The Speaker said:
Correct me if i am wrong but isn't stealth useless in close range as they are detected by then, so why are F35 and F22 armed with cannons? Wouldn't their engagements be limited to long range where cannons are useless.

Why should they be limited but all other fighters are not??
The only difference is they have stealth...and that isn't a handicap.

gambit · Jan 3, 2015

The Speaker said:
Correct me if i am wrong but isn't stealth useless in close range as they are detected by then, so why are F35 and F22 armed with cannons? Wouldn't their engagements be limited to long range where cannons are useless.

You are wrong.

Raptor debuts at Red Flag, dominates skies

Pilots from the 65th and 64th AS, including exchange pilots from the Royal Australian Air Force and Royal Air Force, of Australia and England respectfully, expressed their frustration related to flying against the stealthy F-22.

"The thing denies your ability to put a weapons system on it, even when I can see it through the canopy," said RAAF Squadron Leader Stephen Chappell, F-15 exchange pilot in the 65th AS. "It's the most frustrated I've ever been."

No one knows how the -35 compares to the -22 in terms of low radar observability. May be you can get a radar lock on the -35 within visual range, may be not. May be we will just have to wait a bit longer.

IrbiS · Jan 12, 2015

25mm Apex round designed for F-35 is devastating combining armor piercing, HE, blast fragmentation, incendiary and tracer elements all in one.

sancho · Jan 14, 2015

Cost figures for the F35 out of the Department of Defense Appropriations Bill 2015:

Department of Defense Appropriations Bill 2015.PNG

So if we take the budget estimate, we get to unit costs of:

F35A - $136.65 million
F35B - $200.06 million
F35C - $305.32 million

And this must be fly-away costs right?

Hamartia Antidote · Jan 14, 2015

sancho said:
Cost figures for the F35 out of the Department of Defense Appropriations Bill 2015:

View attachment 183848

So if we take the budget estime, we get to unit costs of:

F35A - $136.65 million
F35B - $305.32 million
F35C - $200.06 million

And this must be fly-away costs right?