Guns on fighter aircraft

[charlielima223]

This is an interesting video. He is by no means an expert but appears to be a well informed/read enthusiast. He gets a few things wrong here and there but for the most part is fairly accurate.


Ironically this video popped up on my youtube suggestion list after I was done reading about the latest DOT&E report regarding the GAU-22 here.
I generally agree with his opinion. I thought this would be an interesting discussion. I've seen small discussion in other topics but nothing dedicated (I'm too lazy to comb through this entire forum for this topic). I know people will bring up future lasers as well as increasing missile reliability and technology.

[basher54321]

A lot of it is wrong of which I am not going to go into - (apart from he missed the F-16A A-A gun kill in 1992 ) suffice to say they are not my opinions - he just needs to spend more years researching the subject.



This is much better because it gives an idea why the F-35C internal gun was omitted and gives his arguments on why an internal gun on the F-35A should be there at all cost.

The need for a Gun on JSF.pdf

The Need for a Permanent Gun System On the F-35 Joint Strike Fighter by Colonel Charles Moore

(324.86 KiB) Downloaded 1136 times

[zero-one]

From Basher's Excellent article

The USAF has prematurely
attempted to burry the gun many times in the past and does not want to make the same
mistake again.

However, is there really a need for a gun system on such an advanced
aircraft? Do we really expect to be “dog fighting” in the battle space of the future?
Doesn’t the advancements in missile technology and stealth technology make the gun
obsolete within the air-to-air environment?

All of these questions must be addressed if
we are going to make informed decisions about the need for such a legacy weapon on
such an advanced aircraft.

Although the AMRAAM is a very effective missile, capable of destroying targets
BVR and WVR, a typical air-to-ground weapons load will only allow the F-35 to carry
two AMRAAMs within its internal bays. However, if tasked solely in the air-to-air role,
the aircraft is capable of increasing the number of internally carried AMRAAMs to four.
The F-35 also has the ability to carry two wingtip mounted Aim-9X missiles that
significantly improve its WVR capabilities. However, this increase in capability comes
with the potential for negative impacts to the aircraft’s RCS. Like the gun pod, engineers
are confident that they can mitigate the negative impacts to the aircrafts signature, but
these promises have yet to be realized. Ultimately, cost benefit analyses of carrying the
Aim-9X will have to be made based on the specifics of each mission.

Therefore, in its most optimum air-to-air configuration the F-35 will be equipped
with four AMRAAMs, two AIM-9Xs, and its internal gun. There is little doubt that this
weapons load, the F-35’s advance sensors/avionics and its RCS will provide it with the
first launch and first kill capability in most environments and against most other aircraft.
However, it is not hard to imagine situations where the F-35 does not detect or kill all the
adversary aircraft it may encounter. The primary reason for this is that air-to-air missiles
do not have a 100% Probability of Kill. Obviously, when faced with a reasonable
number of low-tech adversaries the F-35 may achieve a kill with every BVR AMRAAM
shot it takes. However, against advanced low observable adversary aircraft equipped
with advanced Electronic Counter Measures (ECM), it is not hard to imagine a scenario
where it requires multiple missile shots to achieve one kill. Furthermore, it is not hard to
imagine a scenario in which the aircraft’s missile supply is simply overwhelmed by a
significant number of low-tech adversaries. If the F-35 uses all of its AMRAAMs in the


BVR environment and does not kill all the adversary aircraft, it must then decide whether
to egress the area or engage in the visual environment. It’s noteworthy that the F-35 does
not enjoy the ability to super cruise or achieve the high top end speeds that its brother the
F-22 enjoys. Currently, the F-35 ORD requires the aircraft to be able to accelerate from
.8 Mach to 1.2 Mach in less than 55 seconds at 30,000 feet.4 In addition, the aircraft’s
required top end speed is 1.0 Mach at sea level and 1.5 Mach > 30,000 feet.5

While theseperformance parameters are nothing to scoff at, they do not guarantee the jet the ability to
egress from all fifth generation threats.

If the F-35 cannot egress away from a threat, then it must stay and fight in an
environment where its stealthy signature is severely mitigated. Within the visual
environment, the AIM-9X provides the F-35 with a formable capability. The AIM-9X is
a lethal all aspect IR missile, especially when combined with the F-35’s HMD, but like
the AMRAAM it does not have a 100% Probability of kill. Like any missile, the
Sidewinder is susceptible to countermeasures and defensive maneuvers and killing an
advance adversary with one shot is undoubtedly a difficult task. Furthermore, once the
JSF finds itself maneuvering against an enemy aircraft in a visual environment, it will be
very easy to end up inside the minimum range of both AMRAAM and Sidewinder.6 The
type of WVR fighting the JSF is expected to pursue amplifies this situation. Because of
the development of HMDs /Helmet mounted cueing systems and the abundance of High
Off Bore Sight (HOBS) missiles, most visual engagements will result in aircraft
remaining relatively close to one another. This is because the combination of these
technologies frees the pilot from having to point the nose of his aircraft at his adversary
in order to fire a missile. Even with advanced missiles, remaining close to your


adversary mitigates his ability to maneuver his aircraft in a position that is acceptable for
a missile shot. According to Major Craig Baker, a F-22A pilot, “if you are fighting an
aircraft with a HMD and a HOBS missile you’ve got to keep the fight close and look for
a missile or gun shot.”7
Given all of these considerations, it’s not hard to imagine the
F-35 finding itself in an environment where it is out of missiles or not within missile
parameters and completely dependent upon its gun system to defend itself and complete
its mission.

However, it is not just the limited number of missiles and lack of acceleration/top
end speed that may lead the JSF to find itself in a situation where it needs a gun system.
As mentioned earlier, the F-35 CONOPS requires it to perform OCA and DCA. While
performing both of these missions it is completely feasible that the F-35 may find itself in
a situation where it is defending other assets, air and ground, which it cannot simply
egress or run away from. In these situations, the aircraft may be required to stand and
fight regardless of the number or type of enemy aircraft present. In these situations, you
can never have enough air-to-air ordnance.8

The internal gun system provides the F-35
with additional employment opportunities and may be just the extra firepower necessary
to complete its mission.

Moreover, the F-35’s gun system gives it a very reliable and effective counter air
weapon. As it has been alluded to, air-to-air missiles are far from being 100% reliable.
Although this can be due to several factors, missile reliability, counter measures and
maneuvers, there are other factors to consider.

Both the AMRAAM and the Aim-9Xrequire other aircrafts systems in order to be employed. The AMRAAM, for example,
will be cued to air targets utilizing the F-35s on board radar or Electro-Optical Targeting
System (EOTS). If the aircraft finds itself in a situation where either or both of these
systems are degraded or not working properly, the ability to employ AMRAAM will be
severely degraded if not impossible. Similarly, the Aim-9X requires either the aircrafts
radar, EOTS or HMD in order to be cued to the desired target. Failures in any of these
systems can significantly mitigate the pilot’s ability to employ the missile. It’s also
important to note that several of these supporting systems impact the employment of both
of the aircrafts primary air-to-air weapons. For example, if the F-35 loses it’s on board
radar or HMD, the ability to employ both the AMRAAM and the Aim-9X are seriously
impacted and may make their use impossible.

The F-35’s gun system, on the other hand, is not predicated on other systems and
is extremely difficult to defeat. Although the HMD will make gun employment much
more precise and accurate, it is not required for the pilot to employ the system. All that is
required for an air-to-air gunshot to be effective is for the attacking aircraft to be in range,
in lead, and in the same plane of motion as its target. Once the F-35 finds itself in the
visual environment, being in range for a gunshot is dependent upon many factors such as
both aircraft’s speed, the aspect of the target aircraft and the type of ammunition being
fired. However, with the proposed 25 mm gun system, it’s safe to say that the F-35 will
be within air-to-air gun range when it’s within 5,000 feet of its target. Putting the F-35 in
lead and in the same plane of motion as the target requires flying maneuvers that all JSF
pilots will be trained to perform. However, it is worth noting that unlike the F-22, the
JSF does not have an engine that utilizes vectored thrust. This will make it more difficult
to maneuver to a position from which a gun employment opportunity can be taken. If the


F-35 was dependent upon a gun pod, the impacts on maneuverability would further
complicate this situation and make a gun employment opportunity even more difficult.
Once the problems of range, lead and plane have been solved all that is required is
that the JSF pilot put the aircrafts HMD gun sight on the target. The only way to defeat a
gun shot like this is for the target aircraft to maneuver in such a way that it causes the
bullets to miss. However, with today’s advance predictive gun sights this is much easier
said than done. The bottom line is that all the modern technology in the world cannot
protect an enemy aircraft from the oldest weapon in air-to-air warfare. The gun is simple,
efficient, effective and always available

[outlaw162]

....it’s safe to say that the F-35 will be within air-to-air gun range when it’s within 5,000 feet of its target.

I wouldn't think you'd want to waste any of the 182 rounds just because you're theoretically in range at 5000', unless it was some oddball falling away last chance geometry.

If you have a reasonably stable solution at 5000', one would think you could hold that a few seconds longer....preferably until the target 'filled the windscreen', external factors (other bad guys) permitting. I don't know what the TOF from 5000' is for a GAU-22, but one little jink by the target increases the potential miss distance 2X for a given achievable mil accuracy compared to 2500', the usual preferred optimum range for the M-61.

I've only ever fired the M-39 and M-61, so more knowledgable modern aerial gunnery experts can correct me here if the GAU-22 combined with the F-35 aiming symbology is that reliable at those 'longer' ranges.

I know, "OK boomer."

edit: BTW, having flown an aircraft without an internal gun, I would say it's more 'fighter culture' limiting than mission limiting if you naturally plan to take it into account.

[quicksilver]

A fighter is a small target at 5000’ slant range; it doesn’t take much by the target to invalidate what is already a very low Pk shot.

[zero-one]

A fighter is a small target at 5000’ slant range; it doesn’t take much by the target to invalidate what is already a very low Pk shot.

Maybe not if the target doesn't know you're there in the first place

[h-bomb]

Do fighters still need guns? Probably no. If you are the one pilot, on the 1 in a million time that needs the gun? Yes. Better to have it and not need a gun. Never under estimate that value of a strafing run just to keep the bad guys heads down.

[outlaw162]

Maybe not if the target doesn't know you're there in the first place

How do you know that he doesn't know that you know that he doesn't know?

edit: And if he doesn't know, why shoot at 5000' where he'll know that you think he doesn't know?

[quicksilver]

A fighter is a small target at 5000’ slant range; it doesn’t take much by the target to invalidate what is already a very low Pk shot.

Maybe not if the target doesn't know you're there in the first place

Increase your Pk; close the distance a bit.

[quicksilver]

“Do fighters still need guns?”

Yep.

[wrightwing]

A fighter is a small target at 5000’ slant range; it doesn’t take much by the target to invalidate what is already a very low Pk shot.

Maybe not if the target doesn't know you're there in the first place

Unless you close the distance to ~500' to 1000', your Pk is going to be pretty low. Nobody wants to be at that distance from a foe with HMS/HOBS missiles, if they can help it.

[eloise]

Given that we have guided rocket now, I think something like this is very useful

[spazsinbad]

Somebody mention rockets? We all know about the A-4C shooting down a MiG-17 in Vietnam with a ZUNI - now hear this:

An F-16 Shot Down a Cruise Missile with a Rocket 26 Dec 2019

https://www.popularmechanics.com/milita ... le-rocket/

[charlielima223]

Somebody mention rockets? We all know about the A-4C shooting down a MiG-17 in Vietnam with a ZUNI - now hear this:

An F-16 Shot Down a Cruise Missile with a Rocket 26 Dec 2019

https://www.popularmechanics.com/milita ... le-rocket/

I can imagine some kind of SHORAD systems armed with some sort of CIWS and a pack of guided rockets as a form of missile defense.

[steve2267]

APKWS 70mm Hydra rocket following a laser dot placed on the bandit by a podded or built-in laser designator?

May 1981: Firefly / IFFC -- demonstrated long range / "difficult" target aspects by an F-15B.



My memory said that program demonstrated hits out to 5000ft, but I cannot find such a statement now. Karlo Kopp's article, https://www.ausairpower.net/AADR-IFFC-Sept-82.html, stated hits were obtained at 945m, so basically a kilometer. That's pretty far from what I understand...