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Grey_Mouser67
04-01-2006, 07:09 PM
Just got my latest issue of Flight Journal and there is an excellent article about the FM-2 Wilder Wildcat.

This plane not only have more horsepower, but Grumman took about 700 pounds of weight and 2 HMG's off the aircraft to improve its performance.

The article (take it for what it is) stated that the FM-2 could follow a Zero in every manuever except loops and turns below 180 knots.

Our FM-2 has a FM very similar to the F4F Wildcat...I don't think it is exact, but it does not seem to resemble the Wilder Wildcat at all. The FM-2 is somewhat a forgotten plane in this game, however I'd like to see it perform relattively close to historical values...anyone else do any testing and/or have any good numbers to post for performance?

VW-IceFire
04-01-2006, 07:18 PM
Read the same article just a day ago and I was going to make the same comments. The FM-2 seems to behave much like the F4F-3 except with a slightly different top speed.

Its worth checking into.

Apparently its also missing its HVAR rocket loadout.

Its definately a forgotten aircraft...I wouldn't mind seeing it in a dogfight room or two to see how it handles the late war stuff. Its not going to be fast but it should be very agile with the loss of weight and added power.

VW-IceFire
04-01-2006, 08:02 PM
I can't confirm anything right now as my video card is toast but if someone can look into some things on this...here's some interesting information.



XF4F-8 and FM-2
The increased weight of the F4F-4 made this version less suitable for use on the small decks of escort carriers. However, the Wildcat was more suited to these small, slow carriers than the newer, but also larger and heavier fighters such as the F6F and F4U. Therefore it was decided in 1942 to develop a lighter model. The two prototypes were built by Grumman under the designation XF4F-8, but production aircraft were built by Eastern as the FM-2.

The new Wildcat was powered by the R-1820-56 engine. Previous USN Wildcats were all powered by the R-1830, but the R-1820-56 delivered 1350hp, 150hp more than the engine of the F4F-4, and was also 102kg lighter, with a weight of 604kg. The weight was also reduced by deleting two guns (increasing ammunition to 1720 rounds at the same time) and the reserve fuel tank. The new engine had a single-stage supercharger, and performance at altitude was therefore below that of the F4F-4. But at low levels the performance was considerably better, with a spectacular improvement in climbing rate. The main tasks of the FM-2 were to be submarine patrols and close air support, so performance at high altitude was less important.

The two XF4F-8s were modified F4F-4s. The first one was flown on 8 November 1942. The prototypes were fitted with slotted flaps, but these proved less efficient that the split flaps of earlier models. The XF4F-8 weighed 2433kg empty, 3211kg gross, and 3752kg at max overload. The production FM-2 was, inevitably, a bit heavier.

Characteristic for the engine installation was a rectangular indentation of the forward fuselage aft of the cowling ring, above the wing leading edges, were the exhaust of the engine were grouped. The circular oil coolers under the inboard wing sections were removed. In side view, the FM-2 was easy to identify. And a taller vertical tail was fitted, because of the more powerful torque of the engine. This had other benefits, for the FM-2 now also had fully satisfactory spin recovery characteristics. The tailhook had to be reinforced after combat experienced showed it to be too weak.

Some later aircraft had the -56W or -56WA engines, with water injection. A tank with a 10min water supply was carried. After the 240st aircraft the main fuel tank of 117 US gallons was replaced by one of 126 US gallons, compensating a bit for the deletion of the reserve tank. After the 3301st aircraft provision was made for six 5in rockets.

The first order, for 1265, was signed in early 1943. The final production of the FM-2 was 4127, plus 340 Wildcat Mk.VIs for the FAA. The FM-2 was the most built version of the Wildcat.

http://www.csd.uwo.ca/~pettypi/elevon/baugher_other/f4f.html (http://www.csd.uwo.ca/%7Epettypi/elevon/baugher_other/f4f.html)

Top speed for the FM-2 is apparently 335mph...but alot of sources seem to confuse the F4F-4 with the FM-2 when it comes to performance. So I'm not sure. How does that stack up in IL2 Compare and Hardballs?

mortoma
04-01-2006, 08:53 PM
It overheats like mad too http://forums.ubi.com/images/smilies/16x16_smiley-sad.gif

R_Target
04-01-2006, 09:16 PM
FM-2 is a cool little plane. I haven't flown it in quite a while in PF, but I remember it being no wilder than the other Wildcats.

Nimits
04-01-2006, 11:09 PM
I don't know about the FM-2, but I do know that the performance differences between the F4F-3 and F4F-4 (the F4F-3 was lighter, faster, and more agile) does not seem to be modeled.

Oh well . . . no other game since Aces of the Pacific even bothered to include an F4F-3, let alone an FM-2

horseback
04-01-2006, 11:58 PM
Barrett Tillman wrote the definitive combat history of the Wildcat in 1983: The Wildcat in WWII, (Naval Institute Press). It covers pilot impressions, performance figures, differences between models, the whole magilla.

The Eastern Aircraft (GM) FM-2 was based on Grumman's F4F-8, which "outclimbed the F4F-4 by almost 1,000 feet per minute, and surface ceiling rose to over 36,000 feet." He reports that the average FM-2's top speed was around 320mph. Acceleration was considered pretty good though, and the Wildcat could always turn pretty well (not Zero/Oscar well, but better than anything flown in Europe at the time except the biplanes).

There should be a marked difference between the FM-2 and the Dash-4 Wildcats below 18-20,000 ft in-game, and there isn't. The FM-2 should be quicker and faster, just more responsive overall, with a much better climb.

cheers

horseback

GerritJ9
04-02-2006, 04:34 AM
William Green's "Warplanes of the Second World War: Fighters Volume 4" states that the FM-2's engine had a turbocharger and not a supercharger. So, which is correct?????????
As power went up, so the Cyclone's overheating problems increased until Wright replaced the original nitralloy cylinders, which had the fins machined into them, with a plain nitralloy cylinder with an aluminium sleeve shrunk on; fins were machined into the aluminium.
As for correcting the FM-2's performance, don't hold your breath. I've been trying to get the speed in level flight of all three Buffalo variants corrected for some time now, sending Oleg scans from various publications; all three are grossly undermodelled as far as speed is concerned. So far, however, nothing has been changed, though perhaps Oleg is waiting for the F2A-3 to be ready before he launches the changes....... one can always hope!

fordfan25
04-02-2006, 03:25 PM
yea to bad we cant fool serten people into beleaveing it was a near fantsy plane in the ETO built in the vast numbers of 10's of 5's. maby then it might get a little looking at. its always in this game been a normal wildcat cat with 4 guns a bettter sounding motor and a heat problem. http://forums.ubi.com/images/smilies/51.gif o well.

VMF-214_HaVoK
04-02-2006, 03:31 PM
Its performance is so poor and the overheating issue is so bad Id rather fly the F4F any day. And I usually do.

fordfan25
04-02-2006, 03:40 PM
Originally posted by VMF-214_HaVoK:
Its performance is so poor and the overheating issue is so bad Id rather fly the F4F any day. And I usually do. yea thats what i do. at least you get the two extra guns.

RCAF_Irish_403
04-03-2006, 03:22 AM
weren't the FM2's built by GM?

GerritJ9
04-03-2006, 05:30 AM
The FM-2 shouldn't suffer from overheating as much as it does in PF. By the time it entered service Wright had more or less sorted out the Cyclone's overheating problems.
If the engine was turbocharged rather that supercharged as William Green indicates, the extra 150 hp would have come from the engine no longer having to drive the supercharger fitted previously. Engine efficiency goes up with a turbocharger, the engine delivers more power for the same amount of fuel consumed = same amount of heat generated = same amount of heat that has to be disposed of.

JG53Frankyboy
04-03-2006, 06:34 AM
the FM-2's R-1820-56 had a single stage, two speed supercharger , no turbocharcher.

i have not much experience in flying the Wildcats in the game. but if you trust the lates compare its turn and climb does realy dont look like a "lightweight" Wildcat in comparison to the F4F-3/F4F-4.

well, its like with the F6F and F4U , dissapointing differences between the different versions http://forums.ubi.com/groupee_common/emoticons/icon_frown.gif

J_Weaver
04-03-2006, 03:01 PM
I can't claim to be a Wildcat expert, but as far as in game goes I can see no difference in teh F4F-3, F4F-4 and FM-2. IMO they all share the same fm. If there are any differences they are quite small.

VW-IceFire
04-03-2006, 03:22 PM
Originally posted by J_Weaver:
I can't claim to be a Wildcat expert, but as far as in game goes I can see no difference in teh F4F-3, F4F-4 and FM-2. IMO they all share the same fm. If there are any differences they are quite small.
I would say thats about right. My actual impressions are that the three types are essentially identical. I'm not sure if there is actual differences in terms of the top speeds...there very well may be...but its not perceivable in any great capacity. The FM-2 was supposed to be a fairly hot little fighter to fly...not superb or anything of the sort but the way that the pilots talk about this version and the specs that I've read...it should be something different...you would think.

fordfan25
04-03-2006, 04:48 PM
Originally posted by RCAF_Irish_403:
weren't the FM2's built by GM? yea maby thats the problem http://forums.ubi.com/images/smilies/88.gif

PlaneEater
04-03-2006, 05:15 PM
The FM-2 is more or joined at the hip with the escort carriers, since it was designed for that operating environment. Almost all of the changes they made to it from the F4F were to optimize it as a naval escort / CAP fighter that lived off of the catapults.

As half-hearted as deck operations are modeled in this game, we miss out on a LOT of the experience of flying the FM-2 (not to mention the TBF, which also lived off the escort carriers). I'd say getting its FM right is very important to try and make up the difference.

horseback
04-03-2006, 06:34 PM
Corrections:

1)fighters RARELY used catapults from any carrier (wind over the deck + a full power runup with the brakes on before takeoff usually gave a sufficiently short takeoff run, even on a slow jeep carrier)

2)the F4F-8/FM-2 was simply the natural development of the Wildcat in the event that the Hellcat was unsuccessful

3)the primary role of the FM-2 was ground attack/point defense-the jeep carriers' job was either ASW (especially in the North Atlantic), Naval gunfire spotting, or ground support after the fast carriers cleared most of the enemy air and did the invasion prep of the landing area.

cheers

horseback

3.JG51_BigBear
04-03-2006, 07:07 PM
I don't think the difference in performance should be that great between the models.

The F4F-4 had the folding wings and additional machine gun which made it a little heavier than the F4F-3 but the wing folding mechanism was relatively simple and light-weight. The FM-2 should have a higher rate of climb and a slightly tighter turn radius but its top speed and ceiling should be about the same.

The FM-2 could be considered "hot" in the sense that it was probably the most manueverable fighter left in the Navy's front line arsenal in terms of turn and burn combat and probably felt much lighter and more nimble than the Hellcats and Corsairs.

VW-IceFire
04-03-2006, 08:11 PM
Originally posted by 3.JG51_BigBear:
I don't think the difference in performance should be that great between the models.

The F4F-4 had the folding wings and additional machine gun which made it a little heavier than the F4F-3 but the wing folding mechanism was relatively simple and light-weight. The FM-2 should have a higher rate of climb and a slightly tighter turn radius but its top speed and ceiling should be about the same.

The FM-2 could be considered "hot" in the sense that it was probably the most manueverable fighter left in the Navy's front line arsenal in terms of turn and burn combat and probably felt much lighter and more nimble than the Hellcats and Corsairs.
Not disputing what your saying...I just want to understand. The FM-2 has extra horespower, improved low altitude performance (at expense of higher altitude performance), and with less weight (I think I remember 800lbs stripped out). Should it not have a noticeably different performance or am I expecting too much?

We obviously don't have alot of real benchmarks to go against here so the actual modeling of the type may be correct and its just not something that you can really notice.

horseback
04-03-2006, 09:07 PM
Frontline Naval aviators in May of 1942 were unanimous in their unhappiness about the F4F-4. The folding wing mechanism added 400 lbs (approx 200kg) and the extra gun and added armor piled on another 300 to 400 lbs, without a significant increase in engine power while decreasing firing time by about 5 seconds. From the admirals' standpoint, it was a good tradeoff because a carrier could carry more fighters, but it still boiled down to a less capable individual fighter when the Wildcat was already out performed by the Zero.

The Dash 4 was considerably less zippy than any of the Dash 3 variants, and climbed even more slowly. Only superior ruggedness and better radio comms (allowing more effective team tactics) coupled with a very professional corps of pilots allowed the Wildcat to maintain a better than 1 for 1 victory ratio against the Imperial Japanese Air Arms.

The FM-2 managed to strip off that extra 800 lbs, add a good bit of power and torque and was still able to fold its wings and add a few inches to its tail to counter all that torque. It climbed much better, it got up to speed much quicker (and acceleration is much more important than flat out speed in a fight), and it was very well received at the Joint Fighter Conference of 1944, where only its rearward visibility, top speed and groundhandling were criticized.

It was noticeably better than the F4F-4/FM-1 or -3.

cheers

horseback

PlaneEater
04-03-2006, 09:38 PM
fighters RARELY used catapults from any carrier (wind over the deck + a full power runup with the brakes on before takeoff usually gave a sufficiently short takeoff run, even on a slow jeep carrier)

Can you provide support or evidence for this? Everything I and many others have read is to the contrary. I also have several hours of film footage that contradict this, plus anecdotal evidence such as pilot's statements.

fordfan25
04-03-2006, 09:43 PM
thats what i remember reading back when PF first came out. i had never heard of the FM2 variant and was woundering what the deff was. i read threw some old books of a friend and browsing around the net and i read that it had a much improved clib rate and its handling was much better. i remember reading a piolets comments about how he "felt" things would have gone alot better in the earler days of the war had thay had the fm2 instead of the -4 and even the -3. dont ask for a link because i dout i could find it again lol. in this game though there is no deffernce in FM as far as how the fighter handles over the other two. ill break away from oblivion for a bit and test its top SL speed against the -3 just to see.

3.JG51_BigBear
04-03-2006, 09:43 PM
The figures I have show an increase in empty weight of 310lbs from the F4F-4 to the FM-2.

fordfan25
04-03-2006, 09:56 PM
ok crimra map. sealevel. rad's closed. 25%,weapons default,full power i could manetain roughly 445km/h for the -3 and 470 with the Fm2. thats true speed useing wounder woman veiw. i did not test heat but unless things have changed alot sence around 4.01 i am 100% sure the fm2 over heats a good bit faster and is haredr to kool down. so less wait on the FM2 plus higher out put motor only gives 25 extra km/h. what do you guys think. ill do some better testing of the turn rate and stall charicteristics later. i hae gobilns to slay right now. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

some links http://www.cavanaughflightmuseum.com/Aircraft/Wildcat/Page1.html

http://www.history.navy.mil/photos/ac-usn22/f-types/fm2.htm

acording to that last link the fm-2 had a topspeed of 332mph the wild cat i think had 315 if im not mistaken

http://www.daveswarbirds.com/usplanes/aircraft/fm-2.htm

R_Target
04-03-2006, 10:04 PM
I got the -3 and -4 up to 465, and the FM-2 to 470, same method. 25% fuel and 100% fuel results were the same. I'll check again.

fordfan25
04-03-2006, 10:09 PM
Originally posted by R_Target:
I got the -3 and -4 up to 465, and the FM-2 to 470, same method. 25% fuel and 100% fuel results were the same. I'll check again. what are your defuculty game settings? i could just bairly keep the -3 at 445 trimed ect. ill test again to be sure. im useing full real sept for overheat

fordfan25
04-03-2006, 10:12 PM
ok your right. this time i could maintain roughly 460kmh i must have put rad to open instead of closed opps. make's the FM2 look that much worse lol.

fordfan25
04-03-2006, 10:24 PM
ok as far as turn rate thay are from what i can tell the same.took both planes down to the deck. "same load out as before" NO TRIM as i did not want to throw any more human error or defernce in flight charicteristic varieanse's *spelling i know*. full power. left hand turn. i tried to make the tightst turn i could. in wide screen veiw wounderwoman veiw i tried my best to keep the cross hairs more or less 2 inchs above horizon on my 17inch POS monotor. and watched the speed.and how tight the turn was by watching land mass's for refernce. both planes got squirly at around 230mph true speed thay wanted to dip the right wing. im sure i could have turned them at lower speed but i was testing there combat mavuvering abilty. i made two attempts in both -3 and FM2. i could tell NO deffernce other than the sound of the motor. UMMV

R_Target
04-03-2006, 10:31 PM
I double checked also, same results. I thought I may have checked those speeds the other day w/o any ammo, but it didn't make any difference, ammo or empty. No difference between 25% and 100% fuel either.

fordfan25
04-03-2006, 10:42 PM
Originally posted by R_Target:
I double checked also, same results. I thought I may have checked those speeds the other day w/o any ammo, but it didn't make any difference, ammo or empty. No difference between 25% and 100% fuel either. wow. yea something is -afoot- . did i spell that right. iv never used that term before. afoot, hmmm google

horseback
04-04-2006, 10:26 AM
Originally posted by PlaneEater:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">fighters RARELY used catapults from any carrier (wind over the deck + a full power runup with the brakes on before takeoff usually gave a sufficiently short takeoff run, even on a slow jeep carrier)

Can you provide support or evidence for this? Everything I and many others have read is to the contrary. I also have several hours of film footage that contradict this, plus anecdotal evidence such as pilot's statements. </div></BLOCKQUOTE>Catapult takeoffs were (and are) much more dramatic than a straight runoff from the deck. If they make better TV, that's what they are going to show you. Most of the wartime footage was taken for its propaganda value rather than its historical value.

Pilots are only going to answer the questions that they are asked, and I'll bet that because you heard the word "launch", you assumed that it absolutely meant a cat shot, because that's what you associate with carrier operations. Certainly, with the heavy birds on the carriers today, the catapult launch is usually necessary, but it wasn't often needed for the much lighter prop planes of WWII.

The first light carriers lacked catapults entirely, and except for very heavily laden aircraft (rare until late in the war), they were usually unnecessary. Believe me, if they could get Doolittle's B-25s off the ESSEX in heavy weather without catapults, a Wildcat with much better wingloading and power to weight can make it in a significantly shorter run.

Admittedly, operations in the North Atlantic made greater use of catapult launches, because they were actually safer in heavy weather. But the rule of thumb was that the catapults were only used when necessary; they used a good chunk of the ships' steam power, needed to maintain their speed, and took longer to set up for each launch.

Take a look at Osprey's Aircraft of the Aces #3, Wildcat Aces of World War 2, not one picture of a cat shot in the whole 96 pages. However, if you take a look at the bottom of page 73, you'll see a very impressive headon shot of a Wildcat MK IV preparing for the kind of takeoff I described.

I'm assuming that you haven't spent much time at sea; after three years on a Fast Frigate, I can tell you with some authority that it's windy at sea, usually 10 or 15 knots. Add the speed of the ship going into that wind, and you get 25-30 kts across the bow to add to what you can get running up the engine to its max while standing on the brakes and then starting a two or three hundred foot run with 3/4 flaps. Add the altitude of the deck to the equation; you're at least thirty or forty feet off the ocean surface as well.

Hellcats, Helldivers and Corsairs had a tougher time with the short decks, and that was the main reason the Wildcats and TBM Avengers operated off the smaller deck carriers. However, off the big and medium sized fast carriers (like the Princeton), the usual means of launch for these birds did not include catapults either.

cheers

horseback

joeap
04-04-2006, 11:56 AM
Great post horseback, errr except that Doolittle and his pilots took off from Hornet, not Essex. http://forums.ubi.com/images/smilies/halo.gif

Sergio_101
04-04-2006, 04:46 PM
Originally posted by joeap:
Great post horseback, errr except that Doolittle and his pilots took off from Hornet, not Essex. http://forums.ubi.com/images/smilies/halo.gif

True.

According to Angelucci&Bowers...
FM2 GM manufactured,
Wright R-1820-56 9 cylinder radial
top speed 332 mph @ 28,000 feet
Climb in one minute, 3650 feet
Climb to 10,000 feet, 4.5 minutes

F4F-4 Grumman manufactured,
P&W R-1830-36 14 cylinder radial two stage supercharger
top speed 320 mph @ 18,800 feet
Climb in one minute, 2050 feet
Climb to 10,000 feet, 5.6 minutes

The FM2 was powered by the Wright R-1820 "G" series
engine similar to the engine that powered the B-17F and B-17G.
The crank case and cylinders were steel forgings, this is true of most
Wright radials of WWII. With the G series the
over heating gremlins that had caused problems
in early R-1820s had been solved.

Two other factors in the FM2s superior performance is
a slower propeller RPM (Higher ratio gearing)
and the use of a two speed single stage supercharger.
Before you guys jump on this, there is some
differing opinions on the two speed unit.
I have seen one in pieces, the -56 has a two speed supercharger
but not a two STAGE unit.

The R-1820-56 made more power and torque at the right time.


As to the modeling in this game, I feel the climb
is undermodeled a bit, but timing it is not easy
and the load out is a factor.

But, the FM2 could out climb a F6F-5 Hellcat easily.
In inital climb when a FM2 was at 3650 feet the F6F-5
would be 800 feet below!

Sergio

VW-IceFire
04-04-2006, 05:06 PM
Interesting...so our FM-2 is performing basically at the same level as the F4F's at sea level. What about at some higher altitudes. I noticed that the top speed of the FM-2 is set at 28,000 feet while the F4F is at 18,000 feet. So obviously their power levels are going to be different...what also strikes me as odd is why the aircraft achieves its highest performance at 28,000 feet when the FM-2 was supposedly designed as the low altitude Wildcat...used for supporting the ground troops, strafing, ASW, and artillery spotting.

Any thoughts?

horseback
04-04-2006, 07:12 PM
Originally posted by joeap:
Great post horseback, errr except that Doolittle and his pilots took off from Hornet, not Essex. http://forums.ubi.com/images/smilies/halo.gif Oops. See what happens when you rely on your memory after reading McCampbell's Heros, and taking a double dose of children's cough syrup for your cold?

cheers

horseback

fordfan25
04-05-2006, 12:59 PM
Originally posted by horseback:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by joeap:
Great post horseback, errr except that Doolittle and his pilots took off from Hornet, not Essex. http://forums.ubi.com/images/smilies/halo.gif Oops. See what happens when you rely on your memory after reading McCampbell's Heros, and taking a double dose of children's cough syrup for your cold?

cheers

horseback </div></BLOCKQUOTE>hahaaha you n00b http://forums.ubi.com/images/smilies/59.gif http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Max.Power
04-05-2006, 02:03 PM
Don't **** me, I know the issues about il2 compare, but anyways, il2 compare shows that the fm-2 turns slighly worse at low speeds and is slightly faster at high altitudes. Below 4,000m, the f4f-2 is faster. Out of the f4f-2, the f4f-4 and the fm-2, the f4f-2 seems to be the superior plane in all aspects by a slight margin (according to il2 compare).