Best dogfight gun?

On 16 Dec 2003 23:36:41 -0800, (Tony Williams) wrote:

"Brett" wrote in message ...
"Tony Williams" wrote:
"Brett" wrote in message
...

__Burbage emphasized that both the BK 27 and GAU-12 were able to meet
JSF's lethality requirements, which include probability of kill and
accuracy. He said the GAU-12, which has a higher rate of fire than the
BK 27, was able to meet the requirement by putting more rounds on the
target.
"Performance and affordability are equally important in our selection
process," Burbage said. "If we have two candidates that are comparable
in technical performance, but have significant differences in terms of
affordability, we will pick the one that is more affordable."

Burbage also said there were more technical negatives against the BK 27
than the GAU-12. Cost in three areas, unit recurring fly-away cost,
ammunition, and operational support, tilted the decision in favor of the
GAU-12, he said.

"In all three areas, there was a benefit to the GAU-12," Burbage said.__

see: http://stage.defensedaily.com/VIP/dd...ddi1122.htm#A3

Having studied that article, a couple of interesting points emerge.
The first is that GD withdrew its proposal for the GAU-12/U in
February 2000 "in part due to a belief that the gun did not meet the
necessary requirements." The second is the comment from Burbage that
"We spent a lot of time balancing performance and cost, looking for
best value."

I find it hard to imagine that GD would make such a mistake in
understanding the requirements (in my experience of tendering, it's
more usual for firms to submit non-compliant tenders then argue why
they should be accepted despite that!). Reading between the lines, it
seems most likely that the GAU-12/U did not meet the original
requirements, but when the costs of the BK 27 became an issue, L-M
revisted the requirements and "balanced" them to allow the GAU-12/U to
compete. Or am I just too cynical about the way things work?

"Too cynical", the M61 20mm Vulcan was apparently also considered during the
evaluation and you appear to forget that all the results of the evaluation
would ultimately be judged by the Air Force JSF office.

Which suggests that the initial 'order of merit' after assessing how
well the competitors met the stated requirement was: first, BK 27,
second GAU-12/U, third M61A2.

That raises the interesting question of why the F/A-18E/F and F/A-22
are equipped with the M61A2 instead of the GAU-12/U - I have wondered
about that before. Yes, the M61 is lighter and faster-firing, but the
extra range, reduced shell flight time and much superior hitting power
would have more than compensated, I would have thought. After all, the
USAF originally planned to move to a 25mm gun in the early 1970s (the
GAU-7/A), and would have done so if it wasn't for technical problems
with the combustible-case ammo.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Military gun and ammunition discussion forum:
http://forums.delphiforums.com/autogun/messages/

The F-35 is optimized for air to ground, while the F-18 and F-22 are
optimized for air to air. Different targets, different guns. The GAU-12
is also used in ground to air.

Al Minyard

Alan Minyard wrote in message . ..
On 16 Dec 2003 23:36:41 -0800, (Tony Williams) wrote:

Which suggests that the initial 'order of merit' after assessing how
well the competitors met the stated requirement was: first, BK 27,
second GAU-12/U, third M61A2.

That raises the interesting question of why the F/A-18E/F and F/A-22
are equipped with the M61A2 instead of the GAU-12/U - I have wondered
about that before. Yes, the M61 is lighter and faster-firing, but the
extra range, reduced shell flight time and much superior hitting power
would have more than compensated, I would have thought. After all, the
USAF originally planned to move to a 25mm gun in the early 1970s (the
GAU-7/A), and would have done so if it wasn't for technical problems
with the combustible-case ammo.

The F-35 is optimized for air to ground, while the F-18 and F-22 are
optimized for air to air. Different targets, different guns. The GAU-12
is also used in ground to air.

Agreed. However, every other nation obviously believes that 27-30mm
guns are nowadays the optimum for fitting to air superiority fighters
as well as for air-to-ground. Even the USAF seemed to believe that a
more powerful weapon was needed for the F-15 fighter when the GAU-7/A
was specified (and although still only 25mm, that was much more potent
than the GAU-12/U).

When guns were still important in air-to-air, around 1970, the RAF
carried out an assessment of the effectiveness of the available
weapons and concluded that the best fighter gun on the market was the
30mm Oerlikon KCA (as fitted to the SAAB Viggen) which fires massive
cartridges as powerful as the A-10's GAU-8/A (in fact, the GAU-8/A's
cartridge was derived from the KCA's).

In the light of all of this, I wonder if the GAU-12/U was even
considered for the F/A-22 and F/A-18E/F? If so, it would be
interesting to see the assessment.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Military gun and ammunition discussion forum:
http://forums.delphiforums.com/autogun/messages/

"Tony Williams" wrote:
Alan Minyard wrote

...

The F-35 is optimized for air to ground, while the F-18 and F-22 are
optimized for air to air. Different targets, different guns. The GAU-12
is also used in ground to air.

Agreed. However, every other nation obviously believes that 27-30mm
guns are nowadays the optimum for fitting to air superiority fighters
as well as for air-to-ground.

Every other nation that has "signed up" for the JSF would appear to have has
also signed up for an internal or pod version of the 25mm GAU-12/U. That
includes the UK whose current views also include that the BK-27 carried by
their Typoons is only there as ballast :-)

"Brett" wrote in message ...
"Tony Williams" wrote:
Alan Minyard wrote

...

The F-35 is optimized for air to ground, while the F-18 and F-22 are
optimized for air to air. Different targets, different guns. The GAU-12
is also used in ground to air.

Agreed. However, every other nation obviously believes that 27-30mm
guns are nowadays the optimum for fitting to air superiority fighters
as well as for air-to-ground.

Every other nation that has "signed up" for the JSF would appear to have has
also signed up for an internal or pod version of the 25mm GAU-12/U. That
includes the UK whose current views also include that the BK-27 carried by
their Typoons is only there as ballast :-)

That's hardly surprising as the cost of developing a different gun
installation would be enormous. For the same reason, the 20mm M61 is
in widespread foreign use simply because US fighters come with it as
standard, not because anyone specifically chose that gun. The only
recent example I can think of, of any non-US maker willingly choosing
a 20mm gun, is the new Korean AT-50, which uses what is essentially a
three-barrel version of the M61A2; but that is a light trainer/attack
plane. Before that, there was the Italian version of the AMX light
strike plane, which fits the M61 presumably because Italy already had
it in service in the F-104; the Brazilian version of the AMX has 30mm
cannon.

Don't talk to me about the RAF's attitude :-( The kindest
interpretation I can put on it is that they offered up the Eurofighter
gun as a saving, knowing they could always add it back later...

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Military gun and ammunition discussion forum:
http://forums.delphiforums.com/autogun/messages/