Double Zero and others, some info on the Aden 25, which I had a little to do with before it got canned.
The idea was it would fire bursts a lot faster than the untrendy 30mm.
The HUD had a burst counter / limiter which I thought a good idea.
Snag was the metallurgy wasn't up to the ( flawed ) theory, so it fired it's own innards along with the shell - they didn't develop the gatling gun all those years ago for no reason - barrel cooling .
Dunsfold armoury tried valiantly but the thing was a lemon.
I's gently disagree that the Aden 25 was 'flawed' or a 'lemon'.
The gun was developed in the late 80s/early 90s by RO to use the then new 25mm NATO round (used by the Bradley and the GAU-12), to give much greater hitting power at longer range. It was a redesign of the Aden 30mm, which was in turn a straight clone of a Mauser 30mm cannon developed at the end of WW2. It turned into a very big redesign, using percussion firing (Aden 30 is electrical) and going at about 1850 rounds per min. Muzzle velocity about twice that of the Aden 30, so significant issues with power and recoil. RO basically couldn't make it work, so it was handed on to a small company (now defunct) based in Ascot, who did a great job of getting it right. On test, it worked a dream, and it remains the world's fastest firing percussion fire cannon. Also very low mechanical wear, and easy servicing, plus low cost rounds. All on schedule and within budget.
However.. the bad news was that the gun development was separate from the pod, and this included the ammo feeds. This led to severe problems with gun jams, but these were, IMHO, fixable. There were also issues with spent links hitting the aircraft, but this was a long known design feature. BAE tried adding great big bulges to catch them, but it always looked like a dodgy solution. By contrast, GD developed the GAU-12 gun and pod together, and this is certainly the right way to go. (They developed a great linkless feed, which avoids the spent link issue).
Metallurgy - there were certainly problems with barrel wear, just like any high rate of fire gun. The answer was the burst limiter, just like the French, US and Soviets have on comparable guns. At normal burst patterns, they were getting decent barrel life.
Gatling guns certainly do have less problems with barrel wear, but due to low rate of fire per barrel, not barrel cooling per se. Gatlings are great, as long as you can stand the weight, and power consumption. The other big advantage of revolver cannon like the Aden is that you get max rate from the first round of the burst - Gatlings spend quite a few rounds getting up to speed. Drives probability of hit way up on short bursts.
Before it was cancelled, I heard a senior Czech gun designer (who did the 30mm for the Flanker) say that the Aden 25 was 'an excellent and revolutionary gun'. Some people never got any credit for that.
In the end, the Aden 25 was cancelled by Air Staffs who were quite clear that guns were no longer required 'in any foreseeable circumstances'. Right.
Bottom line - a fine UK company did a great job in developing a very decent bit of kit, and we failed to get it properly integrated onto the platform. But a 'flawed lemon'? No.
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