Hi Juha,
>>Pilots saw 4*.5 HMG as adequate armament against Japanese a/c and saw also that after you had run out ammo your chances to help the defence of your flat-top or your charges was minimal.
Amsel has just posted an interesting and highly relevant quote over here:
http://www.ww2aircraft.net/forum/aviation/what-wrong-f4f-wildcat-16142.html
"Here is the text of a despatch from Admiral Nimitz to
Admiral King sent on 20 June 1942:
ALL AIR COMBAT REPORTS BATTLE OF MIDWAY EMPHASIZE EXTREME
AND APPARENTLY INCREASED SUPERIORITY PERFORMANCE OF 0 FIGHTERS
X ALTHOUGH THESE PLANES ARE MORE VULNERABLE THAN OURS THE
PRIMARY SOURCE OF ANY COMBAT SUCCESSES TO DATE BY NAVY FIGHTING
PLANES HAS BEEN OWN EXPERT TACTICS OPPOSED TO FAULTY ENEMY
TACTICS X OVERALL RESULTS HAVE BEEN BAD AND WILL BE SERIOUS
AND POTENTIALLY DECISIVE WITH IMPROVEMENT THAT MUST BE EXPECTED
IN ENEMY TACTICS X
CONSIDER ACTION ALL OF FOLLOWING LINES TO BE OF HIGHEST IMPORTANCE
X PROVIDE P-40F PLANES OR COMPARABLE TYPE FOR ALL MARINE FIGHTING
SQUADRONS ASSIGNED TO OUTLYING BASES X IF P-40F OR COMPARABLE TYPE
CAN BE MODIFIED FOR AIRCRAFT CARRIER OPERATIONS PROVIDE THESE
PLANES FOR CARRIER FIGHTING SQUADRONS X TAKE ANY POSSIBLE STEPS
TO LIGHTEN F4F4 AND INCREASE AMMUNITION CAPACITY EVEN AT COST OF
REDUCTION IN NUMBER OF GUNS X GIVE ABSOLUTE PRIORITY TO
PRODUCTION AND DELIVERY NEW F4U FIGHTERS"
It re-enforces your point that the ammunition supply was seen as critically insufficient. There is no direct comparison made to the F4F-3, though of course the hint at a possible reduction of the number of guns is clear.
>If you check the actual ammunition supply, the 4x 12.7 mm battery had 1720 rounds of ammunition while the 6x 12.7 mm battery had only 1440 rounds. What the pilot bemoaned was that the new aircraft had less ammunition, not that the extra guns fired off the same the number of rounds more quickly.
As Ivan just pointed out in another thread, my weight for the 12.7 mm Browning ammunition was too low:
http://www.ww2aircraft.net/forum/weapons-systems-tech/ww2-aircraft-gun-specifications-16005.html
So the comparison with the hypothetical Hispano armament would be yet more unfavourable for the Browning:
4x ,50 Browning M2 - 430 rpg, 33 s duration - 350 kg - 1,1 MW firepower - 37.5 MJ total supply
6x ,50 Browning M2 - 240 rpg, 18 s duration - 370 kg - 1,7 MW firepower -31.4 MJ total supply
Here the Hispano battery with equal firing duration, but superior firepower at lower weight:
2x Hispano II - 325 rpg, 33 s duration - 260 kg - 2,1 MW firepower - 69 MJ total supply
So it would be possible to have the original duration of fire of the original F4F-3 Browning armament at about twice the firepower while saving 90 kg of weight.
(Note that Nimitz' telegraph also strongly suggests that weight savings are necessary for the F4F.)
My error regarding the weight of 12.7 mm ammunition of course affects most comparisons I have made in this thread, but I thought this was the most interesting example, so I'd point it out here and leave the rest uncorrected for now.
(Thanks for bringing up the Wildcat example, I have to admit that I was fixated on the European Theatre before that
Regards,
Henning (HoHun)