F4U1D Vrs P51D

[F4UDOA]

Gentleman,

I know this is a beta release but there are some bones to pick as you can see based on some previous post. The biggest flight discrepancy I have seen so far is the climb performance of the F4U (I love that Airplane so I have the maost Data on it obviously) is
not based on actual climb caracteristics of the A/C. The F4U had a Higher lift angle than it Army counter parts as well as a larger wing area. This means that the F4U climbed more verticaly than say a P-51 that would climb at a flat trajectory. That is why the F4U could leave a carrier deck in 800ft were as a P-51 takes 1200ft to lift off. The best climb speed for a f4U therfore would be lower but its time to climb is less even though the speed is lower. Witness by the 7min climb to 20k. The Army and Navy tested a F4U-1A vrs
a P-51C (Which had better climb and speed than the P-51D model) and found the F4U to be superior in takeoff and climb. AH seems to model every A/C to climb best at 200MPH which is not an acurate reflection of a Navy A/C
Which were true interceptors not Pursuits or escorts as were used by the Army flying a longer ranging war. The idea is point defense for bases or fleets not a long extended climbout. Also speed of the F4U was exceptional at lower alts. sea level and equal to the P-51 at 25k.  being 425mph and slower at 30k were the P-51 speed peaked at 437MPH. This is certainly not relected in AH.
Anyway I hope some changes are made to reflect these issues in your next patch.

Thanx
=DOA=

[Rocket]

S!
I have seen pictures of the Naval Tech Sheets for the hawg.  425 @ 20,000 is the best she will do for flat out running level.
Initial climb rate with 5 min of WEP is 2890fpm.
@ sealevel 135 IAS(knots) 2300 FPM 2mins to 5k
this is for a 11,200lb bird full loadout
14,200 135 IAS(knots) 1800 FPM 3 min to 5k

to 20,000 is
11,200lbs  130 IAS(knots) 1900 FPM 8 min
14,200lbs  130 IAS(knots) 1100 FPM 13 min

I think the torque could be done better.. ie. on landings with throttle down and you see you are going to be short and jam the throttle full she should roll all the way over at landing speeds.
Not sure how close the rest of the FM is.  Need to do some timed climbs and turns.
One of the best tactics used was to roll and dive in a spiral and she could out run any of her enemies.  In a HA she should shine against the IJN.  I am not sure of performance in the dive compared to LW or US planes.
The dive brakes work nice   Many times I have deployed gear then dove to make sure I didn't overspeed dropping 6k on a bogey.  She should be able to drop 1 notch of flap to tighten her turn up but haven't tried it.  I tend to try to turn tooo long still  

you can check http://214th.com/ww2/main_frame.htm
goto musuem .. warbirds
All the tech sheets are there for the plane
The charts are for the USN pilots for climbing, landing, take off etc. They should be pretty accurate I would believe(read not propaganda).  

S!
Rocket


------------------
The Red Dragons
Fierce and Bold
With Honour and Courage

[F4UDOA]

Actually I base most of my data from a book called America's One Hundred Thousand which gets most of it's flight data from the fighter conferances of 1943 and 1944 when these A/C were tested side by side. Also reading the published report of the head to head fight comparisons of the F4U Vrs the Zero and Focke Wolf Fw-190A-5. As well as other A/C. If you read manufacturers Data or the data from Eric Browns Wings of the Navy you may be reading someones recollections or personal bias opinion. The F4U could Out climb the A6M5 Zero the P-51D and the F6F-5 Hellcat. But was not as good as the Focke Wolf FW-190A-5 (although the A-8 was much heavier and could not climb as well) or the SpitIV. The Bf-109G was also an excellent climber. This data is directly from head to head comparisons not opinion or manufacters data. I have read were Republic said that there P-47 could attain a speed of 504mph at 30k in 1944. These speeds are barely attainable today by Reno racing A/c with no armament or armor. By all accounts in WW2 the F4U more than held it's own in the Climb. A climb rate of 2100fpm at sea level would have not even been considered a modern a/c in 1943.

Thanks =DOA=

[F4UDOA]

Rocket,

I just went back and checked the data that you reffered me to. The climb data on the main page is for a F4U-1A and is vague at best. Also if you follow your link to the next page there is an Adobe document you can read or down load. It gives performance specs for the F4U-4 A/C which was 500lbs heavier but had 200 more H/P. This A/C is quoted as having an unloaded climb rate of 4800FPM and a climb to 20k At 4.9 mimutes. And 7.5 minutes to 20k with a full load out. This is essentially the same A/C as the F4U-1d and is only 25Mph faster. It would be impossible for any aircraft to gain over double the climb rate when you add 500lbs and 200HP to the engine and no significant redesign of the Airframe. Anyway I've beaten this dead horse enough for now. I hope someone at AH is reading these post.

Thanks =DOA=

[hitech]

 

It would be impossible for any aircraft to gain over double the climb rate when you add 500lbs and 200HP to the engine and no significant redesign of the Airframe

Care to wager on this impossiblity?

HiTech

[F4UDOA]

Yes I would.
The empty weight when from 8971lbs in the -1D to 9205lbs. The horsepower increased from 2135 to 2380. According to the  test data from from the USN the time to climb went from 7.5min to 6.8 min military power. Combat power the -4 is listed as under 6 min.at 12,039lbs.to 20K. As per USN data in "America's OneHundred thousand".

If you want to make it a wager HI-Tech just find one A/C that doubles its own climb rate with and increase of twohundred HP. and no major redign of the airframe. Especially one that weights 10,000lbs. IE the F6F-6 with the
R-2800-18w. The same engine as the F4U-4.

By the way. Sorry about your airplane shooting up your airplane :^}

[Minotaur]

F4UDOA;

 

It would be impossible for any aircraft to gain over double the climb rate when you add 500lbs and 200HP to the engine and no significant redesign of the Airframe

I would not take that bet on a dare.  But, I'm no expert.

Apples vs Grapefruits

F4U-1D vs RV-8

F4DOA, I fear the words "any aircraft" would lead to your demise in this dogfight.  Keep your hand near the "Eject Lever" bud.  

It might be better for you to land and re-arm, HiTech is a smart cookie you know.

Best of Luck to you, in any case!  

Merry Christmas!

Mino

[hitech]

Hmm my office realy needs another bottle of cragenmore care to send me one after I let you know how this can happen?

HiTech

[indian]

Before you take that bet you should know the F4U-4 was the finest corsair built. Not only did it have more horse power it had an updated engine and Four bladed prop. The wieght is not that great the corsair loves wieght it had little effect on the airframe if any. I have the same book and like it alot. The -4 being a later modle was sure to have aerodynamic improvments done to it so I would not take that bet.

In the Army I worked on a twin turboprop airplane that was 1000lbs heavier then the other to like it my unit had, it had a 300hp advantage over them and could out run them in flight easly. They were the same airframe but different configurations for different missions. Mine had lot more wires in it and different generators to give it more weight.

------------------
Tommy (INDIAN) Toon
  Cherokee Indian
My Homepage
Where you can find the Key Commands in  files for Word6 Wordpad and text mode.

indians Homepage

Aces High Word6 and Wordpad Doc's available on my web site.

[F4UDOA]

I will say this.

Hi-Tech must be a very crafty pilot indeed to be imortalized in Warbirds by having your callsign coded into the offline game. I earned my bones in the AW arena's. However I am not talking about finding a lightweight home built A/C that dramtically improves performance by changing to a more efficient powerplant. I'm talking about a 5 ton fighter A/C that without major redesign could somehow improve climb performance by 100% with and added 500lbs to the airframe. As a great example look at the P-51A vrs the P-51D.
Max P-51 Hp at sea level 1330 vrs P-51D max HP1720 at sea level combat power. Climb performance improves but only from 2300fpm to
3300fpm. Climb is more of a function of design than of just tweeking Hp is my point.
A/C that are design for long range escort by design do not climb as well as short range interceptors. Unless you radically improve HP
or design IE the P-51H or P-47M. Even the F2G Corsair for example. Also the F4U ailerons were not metal covered until the -5 version. My point is however in the end that the F4U-1 and -1D corsair is a better climber that is being indicated by AH.
If your still interested in the bet Hi-Tech
you may fire when ready.

Thanx
=DOA=  

[wells]

Here's a scenerio...

The F4u-1 when it made it's first flight, was only putting out 1800 hp and the prop was designed accordingly.  As time went on, the engine output became better and water injection was added etc, but maybe the extra power wasn't 'useable' due to having the original prop on it.  Sure, there was some added performance, but not as much as could have been.  So the f4u-4 comes along with a 4-bladed prop.  Why go to all the trouble of having all that extra prop drag when there's only a 100 hp increase?  Maybe it was more like a 300 hp increase? (2100 vs 1800 from a prop point of view)...and maybe the prop was designed to handle the power from the added water injection as well, so it's closer to a 650 hp increase (1800 vs 2450)?

Some of the later models may have even put out 2800 hp!  The P-47M and N did!

[F4UDOA]

Nice theory but the first production F4U had a 2100hp engine. And other than the F2G no Corsair (production) ever put out more than
2450HP and that was the -5 version. Yes the Hamilton standard four blade prop did help but were talking about doubling climb rate.
Not just improving it.

Guys, all I am saying is the -1 and -1d were capible of reaching 20k in 7+ minutes. It's documented I swear. I'm not making it up.
And as proof I am saying that there is no way that the -4 model could have performed as it did(20k in under 6min) if the airframe in the -1 didn't allow that kind of climb performance. It's no accident that the F4U was the Navy's weapon of choice for over a decade if it could even make it off the deck to join the party.
Kapish???

Regards
=DOA=

[indian]

Ok First off who do you think wrote WarBirds in the First place. He owned ICI which became Imagic. The extra blade is probably the main increase in climb rate but design changes can and do make a difference. One thing you have to make sure of is that you are looking at a full airplane guns and all loaded some data does not take guns and ammo into effect and most test data was made with no weapons or wing mounts installed it makes a big difference.

I do believe the 4800 fpm is wrong it should be 3800. On page 511 of Americas Hundred Thousand the F4U-4 never reached 4800 nor even 4000 fpm. It looks to me that it show about 3500 for -1D and 3800 for -4. That seems close enough that 200 hp and another blade would produce this amount.

The added blade does not cause drag when it is under power it causes thrust. If it is windmilling then it is drag.

The F4U is my favorite plane and it seems right to me but I am a mechanic not a F4 pilot.

------------------
Tommy (INDIAN) Toon
  Cherokee Indian
My Homepage
Where you can find the Key Commands in  files for Word6 Wordpad and text mode.

indians Homepage

Aces High Word6 and Wordpad Doc's available on my web site.

[wells]

I suppose 2 wings don't add drag either..only lift, right?  Of course there is more drag with 4 blades compared to 3, 33% more!  Unless you are getting 33% more thrust HP out of the prop, it isn't worth going to 4 blades!  Looking back at my propeller design theory...

2450/1850 = 1.32

Almost worth it, huh?

[hitech]

On the 3 v 4 change well's we put a lot of thought into the hp/ climb rate numbers at first appearnce they just don't make since on the f4u. Conclusion we came to is at low speed the 3 bladed prob is at max AOA and can't change the hp into thrust. Since they couldn't make it much longer they elected for the 4 blade prob for better low speed performance.

HiTech