Dive bomber accuracy in perspective.

[Wild_Bill_Kelso]

Right, but the F4Fs didn't seem to be able to smash waves of Vals and Kates when they were escorted by Zeros.

 

[EwenS]

I would say that F4F would have helped a lot in some of those convoy battles the British had both in the Med and North Atlantic, but they never got enough of them in time. They had a few. F4F IMO is pretty lethal threat to He 111, Ju 87, SM.79 and can at least catch Ju 88s in most cases. I don't know the full combat history of the FAA Martlets but it seems like in the key convoy battles they either didn't have any or had just a handful.

Check out the Martlet operations from the first escort carrier Audacity between June 1941 and her loss in Dec 1941.

After the fixed wing Martlet I (71 + 10 lost at sea) & III (30) from French & Greek orders the RN chose to delay delivery of further aircraft until Grumman had developed the folding wing option. They didn't become available until late 1941 with the first going aboard Formidable and Illustrious before they left for the Indian Ocean in early 1942. That batch totalled 90 aircraft. The next batch of 220 Lend Lease aircraft didn't begin to be delivered until mid-1942. It was 1943 before numbers built up for them to go aboard escort carriers.

F4F production was still running at low levels in 1941.

 

[Wild_Bill_Kelso]

Ah I see... yes a shame for the delay, but understandable. I don't know if one Martlet is worth two Sea Hurricanes necessarily

 

[SaparotRob]

They're worth more than that, but again, I'm from Long Island.

 

[Zipper730]

There was also an account of an F4F literally beating a G4M out of the sky. The Grumman was out of ammo. The pilot lowered his landing gear and kept bouncing it off the Betty's wing. That might have been at the Battle of the Coral Sea, though.

Honestly that's a story I'd like to hear... you got more information on that?

It had been mentioned that it was the F4F "that did the heavy lifting" holding the line until the hotter planes arrived.

To some extent that's definitely true, though I think the SBD was probably more important. F4F basically helped prevent catastrophe (in terms of US strike aircraft getting totally decimated or enemy strikes having too easy of a time of it) but they didn't really stop enemy strikes cold or totally protect USN Bombers.

I think both of them played their part to be honest.

 

[SaparotRob]

Honestly that's a story I'd like to hear... you got more information on that?


I think both of them played their part to be honest.

I got it from either a Military Aviation History channel vid, Rex's Hanger or Drachinifel. I accidentally hit the reply button as I was going to take a look.
I'm leaning to Drach but it's a long video.

 

[SaparotRob]

Right, but the F4Fs didn't seem to be able to smash waves of Vals and Kates when they were escorted by Zeros.

They did break 'em up though!

 

[Wild_Bill_Kelso]

I got it from either a Military Aviation History channel vid, Rex's Hanger or Drachinifel. I accidentally hit the reply button as I was going to take a look.
I'm leaning to Drach but it's a long video.

This incident is in First Team I think, I'll look it up

 

[ThomasP]

Some specs for comparison:
________________________Vmax at Altitude______TTH (Time To Height_____Guns
Martlet Mk I____________313 mph at 14,500 ft____6.7 min to 15,000 ft_____4x .50 cal
Martlet Mk II___________ 317 mph at 14,000 ft____7.5 min to 15,000 ft_____4x .50 cal
Martlet Mk III___________307 mph at 14,000 ft____6.8 min to 15,000 ft_____4x .50 cal
Martlet Mk IV___________298 mph at 14,000 ft____9.4 min to 15,000 ft_____4x .50 cal
Martlet Mk V___________ 320 mph at 18,800 ft____ 12 min to 20,000 ft_____6x .50 cal____F4F-4
_______________________305 mph at 11,500 ft
Martlet Mk VIA__________318 mph at 16,750 ft____6.6 min to 15,000 ft_____4x .50 cal____FM-2
_______________________307 mph at__3,700 ft

SeaHurricane Mk IB_____308 mph at 18,000 ft____ 10 min to 20,000 ft_____8x .303 cal___ navalized Hurricane Mk I
SeaHurricane Mk IIC____ 320 mph at 19,500 ft____9.5 min to 20,000 ft_____4x 20mm_____navalized Hurricane Mk IIC
_______________________300 mph at 12,000 ft

NOTE All speeds are at Military power. TTH are at Military then Normal for the Martlets, and at Normal for the SeaHurricanes

 

[Shortround6]

NOTE All speeds are at Military power. TTH are Military then Normal for the Martlets, and Normal for the SeaHurricanes

I would note that the time limit for Military power for the US was 5 minutes after which the power was reduced to normal.


I would also note that the USN was using a bit of deception at times in that a "normal" fighter was operating at hundreds of pounds below gross weight and an "over loaded" fighter was operating a full gross weight clean. This was changed during the war but even if late 1942 this stuff was showing up in the spec sheets.
The "normal" F4F-4 was rated at 110 US gallons of fuel and four .50 cal guns with 200rpg (800 rounds total) while the overload F4F-4 held 144 US gallons internal and held the full six .50 guns and 1440 rounds of ammunition.

 

[Wild_Bill_Kelso]

Some specs for comparison:
________________________Vmax at Altitude______TTH (Time To Height_____Guns
Martlet Mk I____________313 mph at 14,500 ft____6.7 min to 15,000 ft_____4x .50 cal
Martlet Mk II___________ 317 mph at 14,000 ft____7.5 min to 15,000 ft_____4x .50 cal
Martlet Mk III___________307 mph at 14,000 ft____6.8 min to 15,000 ft_____4x .50 cal
Martlet Mk IV___________298 mph at 14,000 ft____9.4 min to 15,000 ft_____4x .50 cal
Martlet Mk V___________ 320 mph at 18,800 ft____ 12 min to 20,000 ft_____6x .50 cal____F4F-4
_______________________305 mph at 11,500 ft
Martlet Mk VIA__________318 mph at 16,750 ft____6.6 min to 15,000 ft_____4x .50 cal____FM-2
_______________________307 mph at__3,700 ft

SeaHurricane Mk IB_____308 mph at 18,000 ft____ 10 min to 20,000 ft_____8x .303 cal___ navalized Hurricane Mk I
SeaHurricane Mk IIC____ 320 mph at 19,500 ft____9.5 min to 20,000 ft_____4x 20mm_____navalized Hurricane Mk IIC
_______________________300 mph at 12,000 ft

NOTE All speeds are at Military power. TTH are at Military then Normal for the Martlets, and at Normal for the SeaHurricanes

The issue with the Sea Hurricane vis a vis the Martlet / Wildcat was just that the Sea Hurricane had such short legs. Terrible for a naval fighter.

"16. The short operational endurance of the Hurricane and small amount of ammunition carried must result in frequent turns into wind to land on aircraft which have been in combat, greatly aggravating the position in regard to flying off others or maintaining sections standing by to fly off.""

"The Sea Hurricane's range was recorded as about 450 miles. But it was loiter time that meant the most for carrier operations.

Sea Hurricanes carried only enough fuel to sustain themselves for 1 hour at combat power, and 4.5 hours at full-economical settings. The Fulmar and Martlet could stay aloft for 2 hours and 2 hours 45 minutes under combat power, and 6 hours economical.

The consequence of this was carriers being forced to turn into the wind far more often to take-off and land Sea Hurricanes. So they were often held as 'alert' aircraft on the deck while their longer-legged stablemates maintained the CAP."

Armoured Aircraft Carriers

An overview of the design considerations and evolution of the Hawker Sea Hurricane fleet fighter during World War II.

www.armouredcarriers.com

 

[Wild_Bill_Kelso]

From the same site:

"Minute from First Lord of Admiralty to Prime Minister [AVIA 46/ 136] 6 December 1941
Supply of Grumman Martlet fighters
FIGHTER AIRCRAFT FOR THE FLEET AIR ARM.
I am increasingly anxious as regards the prospective situation of shipborne fighter aircraft. I attach a chart on which graphs show how the aircraft available fail to meet the requirements. It will be seen from the graphs that up to the end of 1942 the situation is apparently satisfactory, but I would point out that this apparently satisfactory position is due to the use of the obsolescent Fulmar in the first line squadrons aided by the supply of 260 Hurricane 'Ones' from the Royal Air Force, which have been converted for use in Carriers, and by the prospective supply of 200 Spitfires, which you yourself were instrumental in obtaining for us from the Royal Air Force subsequent to your visit to H.M.S. INDOMITABLE.
It was hoped that with the supply of Martlets from the United States of America commencing at the rate of 20 per month, as it should have done from October, 1940, we could have kept our heads above water until the new fleet fighters, Firebrand and Firefly, came into effective production. Owing to the failure of the U.S.A. to keep their promise, the situation deteriorates to a marked degree after the end of 1942. We wish to increase the number of Auxiliary Carriers by a total of 15 in 1942, and are considering a further 15 in 1943 and 1944. This will accentuate our difficulty, because although at present the idea of using these Carriers for anti-submarine purposes is predominant, it may well be that Germany will push out her air-raiders to an extent which will require Auxiliary Carriers to be equipped with fighters in addition to anti-submarine craft.
It is clear, therefore, that unless drastic steps are taken to increase the production of fleet fighters, we are likely to be in a nasty hole from the beginning of 1943 onwards. Although we have use of a number of Hurricanes, and in prospect of a number of Spitfires, it must emphasised that these are not really suitable aircraft for operating from Carriers for the following reasons:–
(a) They cannot be used in the small lifts of VICTORIOUS, ILLUSTRIOUS and FORMIDABLE.
(b) Although they can be used in the Carriers fitted with large lifts, they occupy so much more space than a folding aircraft that a drastic reduction in the small number of aircraft which can be carried by any one Carrier is dictated.
(c) Their small endurance requires a Carrier to be turned into the wind so often in order to relieve fighter patrols that the consequent reduction of speed of advance of the ships from which it may be operating is quite unacceptable under certain circumstances.
(d) The R.A.F. aircraft cannot carry the equipment in the way of radio sets and homing beacons, which we have found necessary, for successful operations from Carriers…
The American folding fleet fighter is the ideal aircraft for the job, but here again the productive capacity of the United States is barely sufficient to meet the requirements of their own Navy, which is much behind in modern aircraft owing to the fact that Congress has not allowed them to change their aircraft more than once every five years."

 

[Shortround6]

The USN also had some problems in their destroyers as not all of them had high angle 5 inch guns, as in the Porter Class (launched 1935-36):

The US, some like some other navies, had several different Destroyer designs. This was complicated in 1930s by the naval treaties lapsing.
The US started building late, with their stockpile of WW I four stackers they didn't build a new destroyer until 1934.
The Porters were a special case. The US was chronically short of light of light cruisers or even destroyer "leaders" and the Porters were an attempt to remedy this, while meeting a treaty limit of 1850 tons and the DP capability of the 5in/38s had to go in order to keep eight guns and meet the weight limit. But they only build eight Porters before going back to the smaller 4 gun DP destroyers. The Porters were to add 'punch' to the destroyers to fight their way through the enemy screening destroyers for the big torpedo strike. The Porters were followed by five Somers class and that was the end of the single purpose 5in/38 in either single or twin mount in destroyers. Considering the hundreds of US destroyers built they are just a foot note.
The role of the Porters was somewhat taken over by the Atlanta class light cruisers or the number of US cruisers with 6in guns built or planned in the early part of of WW II (52 Cleveland's ordered)

The US had plans for other guns but stuck with the 5in/38s and in the end were well served by them.

The British were not ignorant of the problems of lack of AA for escorts and the Hunt class had been designed, ordered and many of them laid down before Poland in 1939 but it still took closer to 2 years than 1 year for even cheap destroyers. Design was for three twin 4in and a quad 2pdr but somebody had gotten their numbers wrong and they were top heavy and needed one gun mount taken out until new construction was widened by 2 ft 6in and the third mount came back.

 

[Shortround6]

Sea Hurricanes carried only enough fuel to sustain themselves for 1 hour at combat power, and 4.5 hours at full-economical settings. The Fulmar and Martlet could stay aloft for 2 hours and 2 hours 45 minutes under combat power, and 6 hours economical.

Somebody in the original writing was doing a bit of cherry picking.
Nobody was flying around at combat power for between one hour to two hours unless the situation was truly desperate. I would also note that the Martlet didn't have combat power rating in the way that the Hurricane and Fulmar did. The Martlet had a military rating that that was it. The Martlet used 48in or 9lb boost at the most.
Martlet also only carried about 120Imp gallons of fuel without drop tanks. Hurricane carried 97imp gal?
I can believe the Martlet could fly longer, but the difference seems to be pretty amazing. Something in the actual speeds/power settings seems off.

 

[Wild_Bill_Kelso]

Somebody in the original writing was doing a bit of cherry picking.
Nobody was flying around at combat power for between one hour to two hours unless the situation was truly desperate. I would also note that the Martlet didn't have combat power rating in the way that the Hurricane and Fulmar did. The Martlet had a military rating that that was it. The Martlet used 48in or 9lb boost at the most.
Martlet also only carried about 120Imp gallons of fuel without drop tanks. Hurricane carried 97imp gal?
I can believe the Martlet could fly longer, but the difference seems to be pretty amazing. Something in the actual speeds/power settings seems off.

I don't think anything is off. That website is a patriotic leaning Royal Navy fan page, very detailed and tends to be accurate. But it's hardly the only source on this. And it quotes numerous British naval officers from during the war on this exact issue - the flight endurance of the Sea Hurricane being so low that they had to constantly turn the carriers into the wind and couldn't keep up with the needs of launching and recovering other aircraft. They were terrible for CAP for this reason.

There is a long account on there somewhere of the harrowing ordeal of one of the northern convoys and the trouble they had with the Sea Hurricane over this problem.

The Martlet may have only had 20% more fuel but the R-1830 was supposed to be a particularly fuel efficient engine. Do you know what the relative fuel consumption was at cruising power or military power? I don't have the manuals for either aircraft.

Regardless, I don't think armoredcarriers is cherry-picking or lying about anything. If anything they tend to boost British military hardware on the site somewhat optimistically.

Showing the range for the Sea Hurricane IB here (modified Hurricane IIA) at 505 miles.
range for Sea Hurricane IC (modified Hurricane IIC) as the same, 505 miles
Sea Hurricane IIC at 452 miles with two 44 gallon drop tanks!

Right here I see range for the F4F-3 as 860 miles, F4F-4 is shown as 1275 miles, for FM-2 at 1350 miles.

So looks like Wildcats had between one and a half to almost three times the range of a Sea Hurricane, depending on the specific type.

 

[Shortround6]

Right here I see range for the F4F-3 as 860 miles, F4F-4 is shown as 1275 miles, for FM-2 at 1350 miles.

So looks like Wildcats had between one and a half to almost three times the range of a Sea Hurricane, depending on the specific type.

It also depends on wither they had drop tanks or not. The engine/s on the F4F-4 and FM-2 were not that efficient.
Also check to see if the F4F-3 had self sealing tanks or not (no drop tanks) as the fuel capacity dropped from 160 US gallons to 147 US gallons. (around 1/2 hour?)
The 1275-1350 range was with a pair of 58 US gallon drop tanks. Useful for patrol, if the British had them. and assuming you could get off the deck with them.
Take-off run with a 15kt wind went from 410ft to 550 ft by adding two drop tanks. At 25 kts it went from 278 to 390 ft.

Also check the speeds.
The cruising range for the WIldcats was usually around 160mph (not knots) for max endurance.
Cruising range for Hurricanes was often figured at 212mph. However that is at 20,000ft which is rather high for a what the RN was doing. Of course at lower altitude you have the extra fuel you would have burned getting to 20,000ft.

I am sure that the author/s of armorcarriers didn't lie about anything and copied the source material faithfully. I am not so sure about the original authors and if they were overstating their case or trying to shift a bit of the blame over the failure of the Firefly and Firebrand to be coming into service as desired.

Granted the fixed wing Hurricane was not a good solution.

I do like this bit from the original British author.

The American folding fleet fighter is the ideal aircraft for the job, but here again the productive capacity of the United States is barely sufficient to meet the requirements of their own Navy, which is much behind in modern aircraft owing to the fact that Congress has not allowed them to change their aircraft more than once every five years."

I would note that using well used Hurricane Is for conversion to naval fighters was hardly the best solution over 15 months after the MK II Hurricane went into squadron service in the RAF. This was 6 months after the Germans invaded Russia.

 

[EwenS]

But the RAF had not completed conversion of all its units to Hurricane II by the end of 1941. They were still in front line use in the Middle East. When Indomitable ferried Hurricanes from the ME to the FE in Jan 1942 the RAF had to include some Mk.I to make up the numbers.

 

[Reluctant Poster]

I think you are heavily overstating the limitations of the Ju 87. They sunk quite a few ships in convoys in 1941-1942 which weren't in any dock, including quite small ones. They also managed to maul British aircraft carriers.

The later US destroyers do seem to have been better armed than most other nations, aside from their terrible torpedoes, US was a little ahead on naval warfare in many ways IMO, (certainly in terms of the carrier fleet, and radar on the battleships). But even US ships were still highly vulnerable to Japanese bombers in 1942 as we know, and were still taking losses in 1943. More guns and the proximity fuse really started to make a difference in the later war but by then the tide had already turned.

The USN was behind the RN in application of radar, both in installation and more importantly in how to use it properly. The Battle of Cape Mattapan was a textbook example of the use of radar in a night surface action. A year and a half later the USN produced an absolute clown show in the use of radar at Savo Island. If you read "Fighters Over the Fleet " you will also see that British were a least a year ahead of the American in fighter direction.

There was also an account of an F4F literally beating a G4M out of the sky. The Grumman was out of ammo. The pilot lowered his landing gear and kept bouncing it off the Betty's wing. That might have been at the Battle of the Coral Sea, though.

That sounds like early war exaggeration. Similar to B-17s shooting down half a dozen Zeros at a time. Attached is an example of an early war (for the Americans) puff piece. The P-40 and B-17 are crushing the opposition.

 

[RCAFson]

I don't think anything is off. That website is a patriotic leaning Royal Navy fan page, very detailed and tends to be accurate. But it's hardly the only source on this. And it quotes numerous British naval officers from during the war on this exact issue - the flight endurance of the Sea Hurricane being so low that they had to constantly turn the carriers into the wind and couldn't keep up with the needs of launching and recovering other aircraft. They were terrible for CAP for this reason.

There is a long account on there somewhere of the harrowing ordeal of one of the northern convoys and the trouble they had with the Sea Hurricane over this problem.

The Martlet may have only had 20% more fuel but the R-1830 was supposed to be a particularly fuel efficient engine. Do you know what the relative fuel consumption was at cruising power or military power? I don't have the manuals for either aircraft.

Regardless, I don't think armoredcarriers is cherry-picking or lying about anything. If anything they tend to boost British military hardware on the site somewhat optimistically.

Showing the range for the Sea Hurricane IB here (modified Hurricane IIA) at 505 miles.
range for Sea Hurricane IC (modified Hurricane IIC) as the same, 505 miles
Sea Hurricane IIC at 452 miles with two 44 gallon drop tanks!

Right here I see range for the F4F-3 as 860 miles, F4F-4 is shown as 1275 miles, for FM-2 at 1350 miles.

So looks like Wildcats had between one and a half to almost three times the range of a Sea Hurricane, depending on the specific type.

Aircooled engines like the R1830 can be quite economical in a low power cruise, but they consume far more fuel in rated power climbs and at or near full throttle than a liquid cooled Merlin. At Midway, 4 June 1942, 10 F4F-4s flew escort on Hornet's SBDs. During their entire flight they used low power cruise settings and they never encountered enemy aircraft. All ten ditched in an average of 3.5 hours from TO. Based upon fuel consumption charts the actual endurance difference between a Sea Hurricane 1B and an F4F-4 or a folding wing Martlet II (F4F-4A) or a Martlet IV (F4F-4B) is about 30min, if they fly a similar mission profile.

The Sea Hurricane IB had a very low accident rate. During PQ18, not a single SH1B was lost due to deck landing accidents when flying off a ~18 knot CVE (HMS Avenger). You can see the data card for the SH1B here: https://images.squarespace-cdn.com/...E5BF3YF3Z06CJCJM/image-asset.jpeg?format=750w

The Merlin III could reduce fuel consumption to ~16-20 Imperial GPH and this would give it an endurance of 4 to 5 hours during loiter operations although prolonged operation below 1900rpm was not recommended. At 17000ft at 1900rpm fuel consumption was 23 IGPH.

The SH1B had a much higher power to weight ratio than the F4F-4 and it's folding wing variants and it's combat climb performance in FPM was about twice that of the F4F-4. Even the Fulmar II could climb with an F4F-4 to 10K ft or so when using the combat rating of the engine. In Jan 1942 the Fulmar II's Merlin 30 was given approval for 16lb boost and over 1500hp! USN testing of the F4F-4 revealed extremely poor climb rates, even using full military power during the entire climb:

http://www.wwiiaircraftperformance.org/f4f/f4f-4-02135-performance.jpg

IMHO, the Sea Hurricane only gets a bad rep because DK Brown, the test pilot was in love with the Martlet, but it appears that he's remembering the fixed wing Martlet 1 or 2, not the folding wing variants with armour and self sealing tanks that weighed 1000 to 500lbs more than the early variants.

 

[RCAFson]

Against ships with tachometric directors and true dual purpose guns, the Stuka was little more than an aerial target.
Fortunately for the Luftwaffe, the RN didn't have either on its Destroyers.

The performance of the Mk37 and Mk30 5" mount as fitted by the USN to some old RN Cruisers they refitted was so much better than anything the RN had in service, the RN placed an order for 142 ships sets to switch it to the RN's standard Destroyer armament, but Pearl Harbor got in the way and it was off the Lend Lease table.

But why no Tachymetric directors on RN Destroyers?
Lessons not learned.

The RAF didn't have dive bombers or torpedo bombers, it's approved method of attacking ships was using medium bombers dropping bombs from altitude. An against such targets, firing box barrages using a 2 axis director was seen as perfectly adequate, they obligingly flew in on a constant bearing and altitude. But dive bombers moved in 3 axes at once. TTP's could minimise the risk of dive bombers to ships, but it needed a cool nerve, sea room, and speed. Against fast moving ships with sea roam, the Stuka was fairly useless, most of its successes was against ships either in or around harbours or tied up alongside.
Even against slow targets at sea, they weren't all that good, see the effort to sink HMS Terror, a slow lumbering Monitor.

Best Destroyers any of the assorted assorted combatants entered the war with for fighting off air attacks? The USN's Fletcher Class proved to be magnificent ships, by 1942, they started acquiring l20mm and 40mm guns too making them formidable adversaries for aircraft.

Lundstrom in his First Team volumes analysed USN AA performance during the 1942 carrier battles. He estimates that USN AA only shot down 10 IJNAF aircraft at Coral Sea, Midway and Eastern Solomons. At Santa Cruz, where USN ships were more numerous and carried heavier close range armament including the 40mm bofors, he estimates 25 IJNAF aircraft were downed by AA. In every battle, Lundstrom's data shows that 5in AA was very ineffective and really not a factor at all as most kills were by close range fire. However, what is especially noteworthy is that the USN claimed over 200 AA kills during these four battles vs Lundstrom's estimate of 35. Hence the myth of the 5in gun and USN tachymetric AA fire control.