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Grumman saw that it wasn't going to be produced and it was likely the Government had quit paying for testing. The weight issues kind of make me laugh "your 10,900 pound plane weighs too much so we are going to buy a couple of 12,000 pound airplanes instead (Hellcat and Corsair) Same size wing as a Corsair, 303 square feetWithout knowing the actual VMC of the aircraft or how its weight issues were going to be solved along with other problems Grumman didn't want to mess with, it's kind of hard to call the F5F the be all end all of naval fighters in 1941.
Even Grumman was trying to wash their hands of the project by the end of March 1942 with a memo to BuAer stating they had no further interest in the F5F.
I remember the FW187 as well. I didn't and still don't know enough about it to have an opinion.You may have joined after the period of much Fw 187 love.
Seems like we are in a period of XF5F love!
Grumman saw that it wasn't going to be produced and it was likely the Government had quit paying for testing. The weight issues kind of make me laugh "your 10,900 pound plane weighs too much so we are going to buy a couple of 12,000 pound airplanes instead (Hellcat and Corsair) Same size wing as a Corsair, 303 square feet
I agree with that. The self sealing fuel tank issue was, I believe, because of the way Grumman built the tank. Probably should have just stick built it instead of extruded. They also managed to get the Wildcat up to nearly 8,000 pounds on 1,200 hp. "Golly, wonder why the climb rate sucks?" On the XF5F they added all sorts of extra equipment like the radios, made them use bigger engine mounts that would accept multiple engines etc and then griped about weight increase. If you take the 10,900 pound XF5F and add 500 pounds of turbochargers, 150 pounds of armor and a self sealing tank(the reduction in tank capacity should equal out) you have an 11,550 pound plane with 2400 hp from SL to 25,000 feet. Climb should be outstanding, weight carrying ability should be outstanding, it was dived to 505 mph as it was, I'm not seeing a downside here. Same or less weight than a Corsair or Hellcat and available in 1941 if they had worked on it.I think Grumman tried to say good-bye to the airplane in January '41 due to the lack of production potential you mentioned, the Navy may have picked up costs pretty much until September 1942. (Someone may know for a fact one way or another.) Grumman also stated the aircraft design did not lend itself updating to the necessities of things like self-sealing fuel tanks, etc.
In regards to the weight? It had already gone up by 15% and the aircraft was not combat ready. (The USN was already looking at the F7F. And believe it or not in mid-1937 the Navy was thinking the F4U was only going to be about 9,000 lbs.)
I agree with that. The self sealing fuel tank issue was, I believe, because of the way Grumman built the tank. Probably should have just stick built it instead of extruded. They also managed to get the Wildcat up to nearly 8,000 pounds on 1,200 hp. "Golly, wonder why the climb rate sucks?" On the XF5F they added all sorts of extra equipment like the radios, made them use bigger engine mounts that would accept multiple engines etc and then griped about weight increase. If you take the 10,900 pound XF5F and add 500 pounds of turbochargers, 150 pounds of armor and self sealing tank(the reduction in tank capacity should equal out) you have an 11,550 pound plane with 2400 hp from SL to 25,000 feet. Climb should be outstanding, weight carrying ability should be outstanding, it was dived to 505 mph as it was, I'm not seeing a downside here. Same or less weight than a Corsair or Hellcat and available in 1941 if they had worked on it.
Oh I agree on why they didn't work on it, I think the F4F was the main problem. The XF5F was started in 1938, it should have been in production instead of the F4F in the same time period. They could have started production with the XF5F they had and added turbochargers etc a little later. Another humorous thing you brought up, the XF5F is too heavy for a twin engine carrier fighter at 10,900 pounds so let's build a 20,000 pound twin engine carrier fighter that can't actually operate from a carrier and had 0 vision to the rear. By the way I love the F7F.I think you'd be closer to 12K lbs, and we're still raising the VMC. And there's still issues with produce-ability and some stability issues the Navy found objectionable.
And........to beat my favorite dead horse, Grumman had engineers working on the F6F, F7F, TBF, was doing sustaining engineering on the F4F, and was probably seconding engineers to GM by the spring of '42. Ain't got the bodies.
Oh I agree on why they didn't work on it, I think the F4F was the main problem. The XF5F was started in 1938, it should have been in production instead of the F4F in the same time period. They could have started production with the XF5F they had and added turbochargers etc a little later. Another humorous thing you brought up, the XF5F is too heavy for a twin engine carrier fighter at 10,900 pounds so let's build a 20,000 pound twin engine carrier fighter that can't actually operate from a carrier and had 0 vision to the rear. By the way I love the F7F.
FYI I'm agreeing with you on WHY it happened, I just think it was a mistake.
From what I understand the F7F was never cleared to operate from a carrier, too heavy and landed too fastFunny thing is, by the end of 1938 the Essex was authorized and one of the design studies (27G) became the genesis of the CV-41 class with drawings being generated as early as 1940. Once that ball started rolling aircraft like the F7F, XBTD, etc, all became possible. (Remember the Midway was laid down in '43.)
Once the -4N was redesigned for 22 FPS landings after CQ's in 1947 the aircraft was cleared to operate from carriers. Having been designed for the CV-41 class, it was not well suited for the Essex class ships.From what I understand the F7F was never cleared to operate from a carrier, too heavy and landed too fast
Oh ok. Good info. Thank you.Once the -4N was redesigned for 22 FPS landings after CQ's in 1947 the aircraft was cleared to operate from carriers. Having been designed for the CV-41 class, it was not well suited for the Essex class ships.
Oh ok. Good info. Thank you.
At some point one of those will be based at my local airport
That's a real head scratcher Shortround. I don't know. I certainly understand what your saying, but I don't see the point in listing the exact hp at several different altitudes and then testing the airplane at that exact altitude and using a different hp than you listed. "Engine makes 900 hp at 14,000 feet, does 345 mph at 14,000 feet" (but we actually ran engine at 1100 hp, shhh don't tell them) The Buffalo did have a rather small wing area which might contribute to the higher speed at less hp, only 209 square feet vs 260 for the F4F. Personally, I think we need to assume the things listen in a test are factual (unless it's an obvious typing error) if we reject the facts listed in a test such as hp at a given altitude, then we can simply reject any and all tests that we don't like the results from.
I completely understand. I feel the same way about trying to sift through what power was actually available at what altitudes. The non turbo 1820 isn't as documented as well as most other engines. One reason I think the XF5F used the listed hp of 1,000 hp at SL and 4500 feet then used 900 hp at 7300 and 14,000 feet is they list the XF5F as doing 326 at 4500 feet then they list it as doing 324 at 7300 feet which would reflect a loss of 200 hp even though the air is thinner at 7300 feet then at 4500. If hp stayed the same it should be moving faster. Anyway, that is one of my reasons. I still enjoy the chat.The problem is that they aren't telling us what power ratings they actually used. We are left guessing. Some of the other data sheets the rating is listed as in
http://www.alternatewars.com/SAC/SBD-5_Dauntless_ACP_-_1_June_1944.pdf
Where column 1 is military and the others are "normal" power. The sheet for the F5F and the Buffalo don't say what rating was used.
Although I have my doubts about some of the entries. Like who takes off using "normal" power instead of take-off power and why are the distances the same
BTW the engine used in the SBD-5 was pretty much the same engine used in the Buffalo and the F5F, the -60 used a slightly different carburetor and magnetos but the FAA made no distinction between the two engines when they were converted for civilian use.
Trying to compare the different power ratings at different altitudes also gets a bit complicated (at least for me) as the Dauntless does 252mph at 13,800ft using 1000hp (Military rating, high gear in supercharger) and 244mph at 15,700 using 900hp (normal/max con), now 8mph may not seem like much for 100hp but the plane at 15,700ft in air that is about 4% less dense for less drag. However for navy pilots there may have been a 3-5mph difference in the speed of two airplanes using the same power settings (manufacturer usually was not penalised until the performance was off 2-3 % depending on contract) so minor differences may not be that important from a user's point of view.
It is not a matter of rejecting data I don't like as much as it is trying to get the right data. This is not helped when dealing with engines in late 30s and very early 40s when the definitions of different ratings were changing and/or different ratings came into use and displaced some of the older ratings.
Things are not helped when some engines were never given a "military" rating by their manufacturer but were given a "military" rating by either the Army or Navy.
A much simpler procurement problem was with the USN's torpedoes. Its aircraft torpedoes had a quite poor reputation, in comparison with those of Japan, Britain, and Italy. While the USN got its torpedoes via an arsenal system, they did not have the same sort of failures of design with their ships built in naval dockyards and aircraft built at the NAF. I suspect part of the problem was that the USN had decided that torpedoes weren't important. This makes it pretty hard to have an effective submarine force and also tends to severely limit destroyers' value in surface warfare.
The US Navy certainly vacillated over the importance of air launched torpedoes. By the end of the war they were actually reemphasizing the aerial torpedo due to the BurOrd's disappointment in the performance of their armor piercing bombs. Unfortunately it took until 1944 for the USN to get a reliable torpedo.
That is one of the great myths of WWII. The U boats were defeated in May 1943 when Donitz called off the wolf packs.. Anything after that was clean up. The only USN escort carrier in actual escort service at that time was USS Bogue, who's only claim up to that time was U-569 on May 22. HMS Biter's Swordfish had sunk a U-boat in April and in May in conjunction with destroyers while HMS Archer sank one in May. The lions share of the create for the defeat of the wolfpacks goes to the surface vessels of the Royal Navy with the Royal Canadian Navy, RAF, RCAF and RAAF assisting. Suggest reading Black May for an excellent accounting of the great convoy battles of May 1943.And in one stroke of the pen you throw ASW out the window and lose the U-boat war. No Wildcat and no Avenger = no jeep carriers. Or are you going to build enough big deck carriers to cover all the ASW and amphibious support CAS commitments the Jeeps fulfilled? No way you're going to operate that fast heavy air superiority fighter/do-it-all machine off a CVE. Ever wonder why A3s and RA5Cs didn't operate off the smaller Essex class boats? Too much airplane for the deck.
What other shipbuilding programs are you going to sacrifice in order to build enough big decks to allow your air superiority fighter to assume all the missions of naval aviation?
It's McNamara's TFX/F111 boondoggle all over again. One size DOES NOT fit all! Doesn't this smell kind of like a certain current weapons program that has had a few issues along the way? $$$$$$$$$$
Cheers,
Wes
US Navy without air-launched torpedoes in ww2 = boon for the Allied cause?
The Japanese didn't realize how useless the US torpedoes were so they devoted a significant effort into defending against them. Midway might have been a different story if the Zeros stayed high.
Somewhat different, maybe. But considering the almost constant stream of attacks from Midway Island which alternated low and high, Kido Butai was having trouble keeping its CAP armed and fueled. Lack of effective air search radar meant CAP was limited to eyeball range and not effectively ground directed, so dive bombers not likely detected til near their push-over points. Attacks had come from several directions, so CAP had to be somewhat dispersed to be eyeball effective using hand signals under radio silence.Midway might have been a different story if the Zeros stayed high.