Aircraft Guns

[Chinmoy]

Dear All,

I have yet to come across any thread here which do deal with the Guns which the fighters do carry out. I am sorry if it is a repost and would ask the moderators to merge this thread with the existing one, if there is any.

But I do think that a Gun system is an integral part of a Fighter. Leave alone the BVR's and AESA's, but when it comes to airbattle, you can't throw off the Guns. We do have different systems for different platforms like GSh-30-1 for Su-30, M61A1 in almost all there in US arsenal GSh-23 for Tejas.

Lets have an open discussion on the merits and demerits of the systems over here .

 

[Chinmoy]

While going through LCH prog, I did came out with this info on the armament segment that it used GSh-23 instaed of GSh-301 which is there in SU-30MKI. Apart from rate of fire and the working principle, I think GSh-301 is better then GSh-23. So why it has been selected for Tejas instead of GSh-301.
Could someone enlighten me on this?

 

[pmaitra]

LCA is a light fighter with a single engine. MiG-29 is larger than LCA with two engines. The Sukhoi-30 is more or less a larger version of the MiG-29. So, it makes sense to have a calibre that is commensurate with the size of the fighter jet.

 

[Chinmoy]

Got it.... But I think more then the Gun, its the weight of the round which did matter in its choice. GSh-23 weights around 50Kg where as GSh-301 weights 46Kg, but the rounds used by GSh-23 weights 329gm approx whereas that of GSh-301 weights a whooping 832gm. But doesn't this make it less effective then GSh-301 in ground attack mode or against other aircraft during dog fight?

 

[jackprince]

Got it.... But I think more then the Gun, its the weight of the round which did matter in its choice. GSh-23 weights around 50Kg where as GSh-301 weights 46Kg, but the rounds used by GSh-23 weights 329gm approx whereas that of GSh-301 weights a whooping 832gm. But doesn't this make it less effective then GSh-301 in ground attack mode or against other aircraft during dog fight?

Wright of the round do matter as that will affect how many rounds the bird can carry to the fight. But another deciding factor is the recoil of the gun and that recoil's effect on the structure of the bird. MKI has huge effective load capacity and more mass giving it ability to carryore GSh30 rounds as well compensate the vibration sue to recoil with the mass having less structural damage. OTOH, LCA not cannot carry many rounds of GSh30 to be effective in dogfight, the jarring it will have because of GSh30 recoil, will be potentially damaging to it structurally.

However, calibre of the rounds do matter, since GSh30 rounds are high velocity and much more lethal against an enemy fighter. But, again the no. of the rounds the bird is carrying will come to the question for judging the effectiveness. For a air combat the birds need very powerful guns to kill with a minimum no. of rounds, but against a ground target of say a column of army convoy, the no. of rounds will be more important.

 

[Chinmoy]

Wright of the round do matter as that will affect how many rounds the bird can carry to the fight. But another deciding factor is the recoil of the gun and that recoil's effect on the structure of the bird. MKI has huge effective load capacity and more mass giving it ability to carryore GSh30 rounds as well compensate the vibration sue to recoil with the mass having less structural damage. OTOH, LCA not cannot carry many rounds of GSh30 to be effective in dogfight, the jarring it will have because of GSh30 recoil, will be potentially damaging to it structurally.

However, calibre of the rounds do matter, since GSh30 rounds are high velocity and much more lethal against an enemy fighter. But, again the no. of the rounds the bird is carrying will come to the question for judging the effectiveness. For a air combat the birds need very powerful guns to kill with a minimum no. of rounds, but against a ground target of say a column of army convoy, the no. of rounds will be more important.

Then I think Tejas would be better contender in ground attack role as it does carry 220 against 150 that of Su-30. Moreover in my opinion GSh-23 is much more reliable then GSh-301 due to number o barrels and its working principle.

 

[pmaitra]

@Chinmoy, it is not GSh-301. It is GSh-30-1.

GSh: Gryazev Shipunov (the designers)
30: 30 mm.
23: 23 mm.

Check this:

Interesting read: http://www.quarryhs.co.uk/GSh-6-30.htm

 

[pmaitra]

Just like the GSh-30-1 has a 6 barreled Gatling style variant, the GSh-6-30, there is the GAU-8, that is the same 30 mm but is longer, and is used in the A-10.

GAU-8 mounted in A-10

 

[Yumdoot]

@Chinmoy , nobody serious would do a strafing operation these days unless in exceptional circumstances its a case of US expeditionary forces going after two bit Toyota borne terrorists. Guns today are very useful for WVR combat though.

But I don't understand why you concluded that Gsh-23 would be superior to Gsh-30-1.

The way I see it there would not be very much difference. See, Gsh-23 in LCA is a two barrel GAST Gun with a higher rate of fire, while the Gsh-30-1 on the Su-30MKI is a single barrel short recoil operated cannon with a lower rate of fire but with a much bigger shell.

Because of this difference in the rates of fire and the mass of the shell, for nearly similar ranges, the net kinetic energy deposited will not differ very much.

Give or take things and you can figure things. LCA will need larger number of shells because it has a greater rate of fire/depletion. Possibility of 4/5 long bursts would be absolutely necessary in WVR combat.

Both seek to achieve the same thing differently.

Now Gsh-30-2 on Su-25, would be a different beast altogether. Now you can do some serious strafing depositing nearly twice the energy compared to a Su-30MKI and at a much faster initial rate of fire than a Gatling. But again only if you are Russia strafing some random Chechen terrorists.

@pmaitra what is this 6 barrel version of Gsh-30? Any links (reading material). TIA.

 

[pmaitra]

@Yumdoot,

GSh-30-1

GSh-30-6

 

[Yumdoot]

Need some Vodka to gulp that thing in.

Why and what kind of a man thinks of something like that. I thought it would be some really weighty final product. The damn thing is like a baby with a bazooka. I had heard of the theory but never knew somebody would go make it.

 

[pmaitra]

@Yumdoot,

The GSh-6-30 started off as a naval gun to protect ships from incoming missiles. Later on, it was modified and adapted for use on aircraft. Here is a video:

 

[Akim]

Of course GSh-30 is better for combat effectiveness than GSh-23. Therefore, GSh-23 gun is no longer set. This gun has a weak round, which altered with large-caliber cartridge.

 

[Ash]

A picture that emphasises the size of the gun found in the A-10 'warthog'.

Just like the GSh-30-1 has a 6 barreled Gatling style variant, the GSh-6-30, there is the GAU-8, that is the same 30 mm but is longer, and is used in the A-10.

GAU-8 mounted in A-10

 

[Chinmoy]

View attachment 6197


A picture that emphasises the size of the gun found in the A-10 'warthog'.

As far as I know, generally designers fit the gun in an aircraft, but in case or Warthog, they did fit the plane in the gun :biggrin2:.

So what are the main difference there in between Gatling type guns and GSh types apart from the weight ofcourse.

 

[Akim]

GSh-23L
Azerbaijani modernization BRDM.

Т-64Е

GSh-6-30
AZ from tne Belarus

 

[Chinmoy]

@Chinmoy , nobody serious would do a strafing operation these days unless in exceptional circumstances its a case of US expeditionary forces going after two bit Toyota borne terrorists. Guns today are very useful for WVR combat though.

But I don't understand why you concluded that Gsh-23 would be superior to Gsh-30-1.

The way I see it there would not be very much difference. See, Gsh-23 in LCA is a two barrel GAST Gun with a higher rate of fire, while the Gsh-30-1 on the Su-30MKI is a single barrel short recoil operated cannon with a lower rate of fire but with a much bigger shell.

Because of this difference in the rates of fire and the mass of the shell, for nearly similar ranges, the net kinetic energy deposited will not differ very much.

Give or take things and you can figure things. LCA will need larger number of shells because it has a greater rate of fire/depletion. Possibility of 4/5 long bursts would be absolutely necessary in WVR combat.

Both seek to achieve the same thing differently.

Now Gsh-30-2 on Su-25, would be a different beast altogether. Now you can do some serious strafing depositing nearly twice the energy compared to a Su-30MKI and at a much faster initial rate of fire than a Gatling. But again only if you are Russia strafing some random Chechen terrorists.

@pmaitra what is this 6 barrel version of Gsh-30? Any links (reading material). TIA.

Yeah, we could say that strafing is a thing of past, but while designing an aircraft, we can't simply deny that it no longer exist. I think some thought should be put into designing a modern variant of these canons and into a round too which could be intermediate of GSh30 and 23.

 

[pmaitra]

As far as I know, generally designers fit the gun in an aircraft, but in case or Warthog, they did fit the plane in the gun :biggrin2:.

So what are the main difference there in between Gatling type guns and GSh types apart from the weight ofcourse.

• GSh-30-1 is a one off single barreled gun.
• GSh-30-2 is a double barreled gun that works on the Gast principle.
• GSh-30-6 is a six barreled Gatling gun.

 

[Yumdoot]

@Chinmoy to extend the post by pmaitra (posting in 3 parts because requirement is for max 8 pictures)
(cc: @pmaitra)

• GSh-30-1 is a one off single barreled gun. - Revolver gun, where the chambers rotate and as they align with the single barrel. Boom. Like your bollywood pistaul. DEFA, ADEN, Mauser 213 et al.

works like this:

Installed like this:

• GSh-30-2 is a double barreled gun that works on the Gast principle. -

Karl Gast principle was to have a reciprocating lever fulcrumed on to a point, with force arm of the lever propelled backwards with each firing which in turn forces the load arm to cock up the other gun placed sideways. Like this from his patent drawings:

A Russian by the name of 'Much to complex name Silin' modified that a little to use a reciprocating rack and pinion arrangement like this:

I thought somebody had made this into a multibarrel version. Russian/Soviet Gast guns are actually Geared Silin Guns.

 

[Yumdoot]

Contd.

• GSh-30-6 is a six barreled Gatling gun. - This is a gas operated gun rotary cannon. Where the barrel chamber/breach everything rotates like crazy.

Mr. Gatling used to crack his gun by hand. Americans got a motor + cam arrangement (rotor) Like this http://www.thebangswitch.com/garwood-industries-m134g-minigun/:

This is the linear arrangement of the process. Note only one barrel fires & the rest are in the process of loading and unloading.

The Russians instead of the complex electrical and mechanical engineering chose a different path to their needs and used the powder charge gases to power the whole thing.
Link: http://www.kalashnikov.ru/upload/medialibrary/d83/058_065.pdf
Drawings:

Notice unlike in the American gatling this one does not just rotates without recoiling. Slostin gun had each barrel also recoil which cocked-out the barrel of adjacent gun (pushing it outwards and the spend cartridge gets ejected - like in the trop two barrels shown in the linear arrangement above). Obviously the barrel that had already fired is the only one forced outwards and for the rest of the rotation it spends all the time falling back into position to receive another cartridge. A total loading-firing-ejecting sequence being gas operated.

However Slostin went on to design a further improvement the recoil of the barrel was eliminated. And here is how I guess Slostin wanted to do it. It seems a recoil force was transferred onto a linear recoiling piston which had a helical worm gear inside a housing with bearings in the grooves of the helical worm gear. This worm gear in turn would inturn move a circular gear to produce a rotary motion.

Like the following image (notice Rotary Drive #24 where the linear motion gets converted to rotary motion http://www.google.com/patents/EP1529974A2?cl=en)

Linear motion converting to rotary motion like this (notice the axis or orientation of holes):

However both Silin and Slostin experiments had been abandoned by the State. However both Silin (Gsh-30-2) and Slostin (Gsh-6-30) seem to have been refined into a final product which much of the world uses today.

The American gatling is too complex too slow. Gas operation was too smart too fast. Americans also worked on gas operation rotary cannons but they mostly took up Rotor operated Gatling to increase their GDP.