Hawker Hurricane Mk. IIB vs. Grumman F4F-4 Wildcat

[claidemore]

I believe the 8 x .303 Brownings would fire 160 rds per second (20 rds a second or 1150/1200 rds/min per gun) giving a Hurricane a firing time of 17.5 seconds, five/six - 3 seconds bursts. A 12 gun Hurricane IIb would fire 240 rds/second.

4 x .50 at 750-850 rpm would give 50-56 rds per second.

Also, I'd like to point out, that the pilots flying these planes were aware of the convergence problem, and at extremely short ranges, they were known to bring to bear the guns of one wing only, to make sure the enemy plane didn't fly harmlessless throught the 'hole'.

 

[renrich]

I hope you don't think I am saying that the 8 guns have only a 2 second firing time. The two second firing time is based on a closure speed of 180 mph(which does not sound realistic) I suppose the two second window is the length of time the fighter is in range and on target.

 

[claidemore]

Renrich: no misunderstanding bud, just wanted to contribute some numbers to the discussion.

I like numbers, they are the ultimate weapon against colorful rhetoric.

Cheers!

 

[kool kitty89]

I totally agree that 4x .50 cal guns would have been better for the BOB. (plus there would likely be a longer firing time). They probably could have used 6x .50's but that might put a penalty on climb, and ammo load. (particularly important for an interceptor)

It would probably take a 4 sec burst with decent aim and positioning to down an average twin engine bomber at the BOB as long as the pilot focused on the vulnerable areas of the bomber. (fuel tanks, engines, and -depending on armor- cockpit)

 

[renrich]

KK, obviously I have never engaged in ACM or any air to air gunnery but in reading about and talking to men who have engaged in practise shooting at a sleeve and in looking at gun camera film it looks to me, that for most pilots, putting a few bullets into the target anywhere is about the most they can hope for. In other words, shooting at a specific part of the enemy AC is beyond the skill of most pilots.

 

[kool kitty89]

I meant aganst the Bombers, though you can't realy aim at a specific part you can aim in a general area and the inner wings are you're best bet with the engines, fuel tanks and fusalage/crew all in the general area. So it would be most effective to aim just outboard of the fusalage, particularly when outside the convegence zone for the guns.

And outside of gun camera footage and flight sims I dont have any experience in gunnery either...

 

[Elvis]

From the gun camera footage I've seen, over the years (and I don't exactly sit around all day looking at WWII gun camera footage, mind you) it seems to me the practice seemed to be to actually slightly overshoot the target and let them fly into it (or, in the case of strafing runs, undershoot and you fly into the target).

...and no, I don't have any experience firing guns in flight, either.

180MPH closure speed makes me think the formula the British used had been in practice for some time (maybe since the latter half of WWI?), but had never been updated.



Elvis

 

[renrich]

That closure speed seems a little fast to me. A German bomber might be doing 150 mph. Consequently the fighter would have to be making 330 mph. The engineers working that formula may have postulated that the fighter would be in a shallow dive but it seems to me that the fighter would have to be in full military power and in a shallow dive for at least a fair length of time to achieve that speed, especially when that formula was being used in 1933 or so. Perhaps they were thinking the bomber was doing 120 mph and that the British fighters were going to be able to get 300 mph.

 

[kool kitty89]

But that would also have been a time when twin engine bombers were out-performing single eingine fighters. When the Blenheim first apeared no RAF fighter could catch it.

 

[renrich]

All the countries were designing fighters to go 300 mph and were getting there in 1935. Perhaps they were predicting they could go there. How fast would a Blenheim go when it was on a bombing run with a full load of bombs?

 

[Graeme]

when the Brits were evaluating there Buffalo I's in 1941

A&AEE Boscombe Down tested the Buffalo (both British and Belgium models) and produced a report in July 1941.
A few of the salient points from it were;

"The unique undercarriage prove too fragile for service use.
Performance was not outstanding, although take-off run (with flaps) was only 215yds.
Carbon monoxide was dangerously high in the cockpit. Fish-tail exhausts were trialled but proved ineffective but did provide good flame damping qualities.
It was easily loaded to give an excessively unstable (aft) CG. An acceptable limit was found and recommended for the Service.
The aircraft was unsuitable for hot climates on account of predicted excessive oil temperatures.
The gun firing trials of the four 0.5in guns in the British version proved generally satisfactory, but rearming the wing guns was awkward, and firing the guns at low altitude caused oil to obscure the windscreen."

They were rejected as a first-line fighter in Europe following trials by No.71 Squadron based at Church Fenton.

"The aircraft was unsuitable for hot climates on account of predicted excessive oil temperatures."
Knowing this they sent the them to Singapore!, which proved disastrous.

"In an attempt to improve its inferior performance its all-up weight was reduced by changing the 0.5in guns to 0.303 calibre, cutting the ammunition to 350 rounds and restricting the fuel to 84 gallons".

 

[Graeme]

When the Blenheim first apeared no RAF fighter could catch it.

Are you referring to Lord Rothermere's privately produced civil Bristol Type 142 Britain First ? then yes, but surely not the Blenheim bomber of March 1937, as the Spitfire and Hurricane were then in existence?

How fast would a Blenheim go when it was on a bombing run with a full load of bombs?

Obsolete (Blenheim I) by early 1938, it proved unable to exceed 215mph at 10,000ft when carrying a full complement of four 250lb bombs and full fuel.

 

[Elvis]

180MPH closure speed makes me think the formula the British used had been in practice for some time (maybe since the latter half of WWI?), but had never been updated.

That closure speed seems a little fast to me. A German bomber might be doing 150 mph. Consequently the fighter would have to be making 330 mph. The engineers working that formula may have postulated that the fighter would be in a shallow dive but it seems to me that the fighter would have to be in full military power and in a shallow dive for at least a fair length of time to achieve that speed, especially when that formula was being used in 1933 or so. Perhaps they were thinking the bomber was doing 120 mph and that the British fighters were going to be able to get 300 mph.

...and thus, these are the stupid remarks we make when we work 12 hours on 2 hours of sleep.
As usual, Renrich is on the mark.
I stand corrected.






Elvis

 

[HoHun]

Hi again,

>I think the story quoted in post #76 in this thread (link below - hope it works this time) about Hurricanes out-turning Wildcats on a consistent basis is entirely credible:

>http://www.ww2aircraft.net/forum/av...s-grumman-f4f-4-wildcat-1550-2.html#post88018

Below a turn rate analysis for the two types at 0 km, 5 km and 10 km altitude ... doesn't look too good for the Wildcat in direct comparison.

(Clmax used is 1.23 for the Wildcat, 1.2 for the Hurricane.)

Regards,

Henning (HoHun)

 

[kool kitty89]

Are those for the F4F-4?

THe lighter F4F-3 would have had better turn rate though. (as would the FM-2 with its more powerful engine)

 

[HoHun]

Hi Koolkitty,

>Are those for the F4F-4?

Roger.

>THe lighter F4F-3 would have had better turn rate though. (as would the FM-2 with its more powerful engine)

That's right. I'm not sure about the exact weight of the F4F-3 (and the subtle differences of its engine to that of the F4F-4), but using 7000 lbs and the same engine as the F4F-4, I get results for the F4F-3 that are close to, but don't quite match, those of the Hurricane IIB. Only at sea level, where the R-1820-86 enjoys a power boost from running in "neutral blower", my generic F4F-3 is almost equal.

I don't have an engine chart ready for the R-1820-56 of the FM-2, but it appears to be more powerful than the R-1820-86 only near sea level, and the FM-2 is a bit heavier than the F4F-3, so the extra power and the extra mass counteract each other to some degree.

Regards,

Henning (HoHun)

 

[Elvis]

From the good folks at Ken's Aviation...

The name Cyclone was first used by Wright for their P-2 radial engine in 1925.
The R-1820, introduced in 1931, was a improved version of the P-2 with higher displacement.
The R-1820 remained in production through the 1950s by Lycoming and Canadian Pratt Whitney.

9 cylinder, air-cooled, radial
displacement: 1,823 cubic inches (29.9 liters)
bore x stoke: 6.125 x 6.875 inches


R-1820B: 575 hp
R-1820-22: 950 hp
R-1820-33: 775 hp
R-1820-39: 930 hp
R-1820-45: 930 hp
R-1820-51: 1,000 hp w/turbocharger
R-1820-53: 1,000 hp w/turbocharger
R-1820-54: 900 hp
R-1820-65: 1,200 hp w/turbocharger
R-1820-66: 1,350 hp
R-1820-76A: 1,425 hp
R-1820-77: 870 hp
R-1820-80: 1,495 hp
R-1820-82WA: 1,525 hp
R-1820-84: 1,425 hp
R-1820-86: 1,425 hp
R-1820-87: 1,200 hp
R-1820-97: 1,200 hp w/turbocharger
R-1820-103: 1,425 hp







Elvis

 

[claidemore]

I love your graphs HoHun, keep em coming please!

Been following this thread for a while and doing a bit of research online. Here's some numbers (mostly from Wiki, but a few other/better sources as well) and some comparative performance evaluations.

Hurri IIB, 340 mph (w/o trop filter, 320? with) climb 2780 ft/min, range 600 mi, 12x.303 mg, good turn, poor dive.
Wildcat F4F-4, 320 mph, 1950ft/min, range 770 mi, 6x.50mg average turn, excellent dive.
P40B-345-352 mph, 2100 ft/min, range 730 mi, 2x.50 4x.30, good turn, excellent dive
Brewster Buffalo F2A3, 321mph, 2290 ft/min, 965 mi,4x .303 or .50 good/excellent turn, good dive

A6M2-316 mph, 3100 ft/min?, 1200 mi, 2x20mm 2x 7.7, excellent turn, poor dive
Ki-43 II Hayabusa, 329mph, 29-3000ft/min, 1000 mi, 2x7.7 +1x 13mm or 2 x 13mm, excellent turn, poor dive
Ki-27 Nate, 275 mph, 3010 ft/min, 390 mi, 2 x 7.7 , excellent turn, poor dive

Looking at these numbers and hopefully objective 'general' comparisons of turn and dive characteristics, I can see why the Hurricane might not fare so well against the 1942 Japanese fighters.

It really didn't have any distinct advantages in flight performance. It could not climb, turn or dive better than an Oscar, Nate or Zero. It did have a max speed advantage over the Nate. Apparently the Buffalo could dive away from the Japanese planes, and those pilots/squadrons who did so enjoyed relative success. (in looking at the various engagements fought by Hurricanes in Burma 1942, they almost never had a tactical advantage at the start of a fight, which didn't help their record. Bad luck and no significant perf advantage = poor success)

Both the Wildcat and P40 had much better dive speeds, and general concesus seems to be that this was the advantage that they exploited successfully. P40 also had a max speed advantage.

In the mock dogfight of anti-sub Hurricanes against Wildcats, the Hurri was able to get on the Wildcats tail and stay there. Since it could outclimb and outturn the Wildcat, this is no surprise. A Zero or Oscar would have done the same.

As much as I admire the Hurricane, the P40 replaced it in North Africa in the fighter role with the RAF, and the Spitfire replaced it in Northern Europe and eventually in the CBI theatre. P40s also replaced it in Canada with the home based fighter squadrons, most notably in the Aleutian campaign. This in spite of the fact that Hurricanes were being built in Canada.

The Hurricane was a good plane, even a good fighter, but an excellent fighter has to be able to do at least one thing much better than its opposition to have consistent success.

 

[HoHun]

Hi Claidemore,

>I love your graphs HoHun, keep em coming please!

Glad they're appreciated

>It really didn't have any distinct advantages in flight performance. It could not climb, turn or dive better than an Oscar, Nate or Zero.

Well, from my limited knowledge I tend to think it was actually a better diver than the Japanese types. Below 5000 m, it certainly held quite a distinct speed advantage over the A6M2, too.

It's important to remember that the Spitfire V, which held all the technological advantages you mentioned over the A6M, did not fare too well in the direct matchup either. That really points to a tactical rather than to a technical background.

>P40 also had a max speed advantage.

The P-40 is another interesting case as it racked up quite a record against the Japanese, while being considered an inferior fighter in direct comparison to the Spitfire V in Africa. That seems to fit my perception of the importance of tactics ...

Regards,

Henning (HoHun)

 

[claidemore]

HoHun,

I agree with you 100% on your take on tactics. It was mentioned earlier in this thread that the Hurricane did much better vs the Japanese planes in 1943 and onwards. The Hurris were the same, but the Oscars were all type II and type III, much better planes, (type III 360 mph) so the difference in results has to be tactics.

About the Hurricane dive speed: I could not find a max dive speed for a Hurricane anywhere. I'm guessing one of you aeronatical computating guys could figure that out!
Given it's sturdy construction, you are probably right that it would have had a max dive speed greater than the lightly built Oscar or Zero. What I did find concerning the Hurricane , was that it built up speed very slowly in the dive as well as reports that 109s could easily dive away from them. Poor initial dive speed would make it difficult to disengage, hence my 'conclusion' of poor dive characteristics.

If somebody knows the max dive speed on these planes, feel free to point out my erroneous conclusion!