Author Topic: The 1.05 planes  (Read 1014 times)

Offline StSanta

  • Gold Member
  • *****
  • Posts: 2496
The 1.05 planes
« Reply #15 on: September 20, 2000, 01:32:00 PM »
Thanks guys, much appreciated  

------------------
StSanta
JG54 "Grünherz"
"Trespassers will be shot. Survivors will be shot again"
 

[This message has been edited by StSanta (edited 09-20-2000).]

Offline Ripsnort

  • Radioactive Member
  • *******
  • Posts: 27260
The 1.05 planes
« Reply #16 on: September 20, 2000, 01:40:00 PM »
Type: P-47D-30-RE
Function: fighter
Year: 1943 Crew: 1 Engines: 1 * 1865kW P&W R-2800-59
Wing Span: 12.42m Length: 10.99m Height: 4.44m Wing Area: 27.9m2
Empty Weight: 4812kg Max.Weight: 7900kg
Max. Speed: 687km/h Ceiling: 12800m Max. Range: 2900km
Armament: 8*mg12.7mm 1135kg

 
Quote
Nath:The F4U1D had a 8W, which delivered 2,250 hp at maximum compared to F6F5's 2,000 hp. I don't know what powerplant the P47D-30 or -25 had but i assume its the R-2800-59, 2,000 hp for it both at take off and 30,000 ft, P47 should perform the same as F6F below 15k I assume.

So, tell me this, why can I climb to 20k faster in a P47D than a F4U, when the F4U is lighter, and has more power?

Offline Ripsnort

  • Radioactive Member
  • *******
  • Posts: 27260
The 1.05 planes
« Reply #17 on: September 20, 2000, 01:42:00 PM »
Santa, you're going to make more enemies than friends with that signature, including me.

Nath-BDP

  • Guest
The 1.05 planes
« Reply #18 on: September 20, 2000, 01:53:00 PM »
Because 1D has 2,250 hp at take off, but losses it when alt is gained... with the P47D30 you stay at 2,000 hp all the way to 30k.

Offline Ripsnort

  • Radioactive Member
  • *******
  • Posts: 27260
The 1.05 planes
« Reply #19 on: September 20, 2000, 02:06:00 PM »
Nath, do you have any idea what it 'loses' it too? Like does it reduce to 1800 HP output or less?  Just seems like the F4U should be a better climber than the P47D historically, I'm gonna ask some guys down at the flight museum, that actually worked on these birds, see what they have to say.

Offline miko2d

  • Parolee
  • Gold Member
  • *****
  • Posts: 3177
The 1.05 planes
« Reply #20 on: September 20, 2000, 02:11:00 PM »
 Santa,
 Your sig looks like some kind of religious statement or, rather, denunciation.
 Are you sure it's the right forum for it?
 miko

Offline F4UDOA

  • Silver Member
  • ****
  • Posts: 1731
      • http://mywebpages.comcast.net/markw4/index.html
The 1.05 planes
« Reply #21 on: September 20, 2000, 04:01:00 PM »
Gents,

The Topic of climb in an F4U has alway's been an anomally(Spelling)? The F4U-1D is listed at 2250HP at sea level and the power drops off to only 1900HP at 20K. It is listed as climbing at 3150FPM and 7+min to 20K. However in head to head test against the P-51B(listed as outclimbing the Mustang by 700FPM not as good as the 190 better than the Zero and F6F), Fw-190A5, A6M-5 Zero and F6F Hellcat it bested those numbers by a considerable amount. As well as having less weight and drag than a P-47D and better power loading and wing loading.

So why the better rated climb? Well I have alway's believed that some A/C specs are over rated by either the service or manufacturer. Take for example the the
P47-D30. The addition of water injection added 600Hp to the engine for short periods of time raising the climb from 2500FPM at Military power to roughly 3400FPM. The
F4U-1D also had water injection which raised the rated power 250HP fro 2000HP to 2250HP and climb values from Roughly 2800FPM at Military power to 3150FPM. Cosidering they both had the nearly the same water injection the P-47 benifited by a geat amount more than the F4U. Enough to make the P-47 climb almost 1,000FPM better than at military power I don't know. It was not the case in the ealier versions of the P-47 with water injection until the D25.

The other factor is the Propeller which is the quoted reason from republic on the climb gain in the P-47 from the early D model to the late. It was given a Hamilton Standard 4 blade paddle blade prop. However the F4U was already using a HS paddle blade prop at the time. What ever the case I have sworn off debating these subjects until I see Badboy's breakdown of A/C performance which I have been waiting to be published for some time.
Until then if Well's or anyone else has a good explanation I would be happy to listen.

Later
F4UDOA

Offline -ammo-

  • Platinum Member
  • ******
  • Posts: 5124
The 1.05 planes
« Reply #22 on: September 20, 2000, 04:10:00 PM »
agreed Miko


santa-
Are you making an attemp at being funny? Just want to be the antagonist? That IS offensive to me.

ammo
Commanding Officer, 56 Fighter Group
Retired USAF - 1988 - 2011

Offline Jigster

  • Copper Member
  • **
  • Posts: 107
      • http://www.33rd.org
The 1.05 planes
« Reply #23 on: September 20, 2000, 05:51:00 PM »
Rip, remember the P-47's have a super charger behind the cockpit that is the size of your average washing machine along with some of the most efficent ducting work concieved.

The F4U has a much much smaller 2 stage blower mounted directly on the engine, thats a little over a foot in diameter and 6 inchs thick. The F6F has pretty much the same type that loses power over 10k all the way to 19k where the second stage kicks in.

From 14k to 19k most US fighers lose power until the second gearing for the super charger kicks in and draws more air. The exceptions US fighters being the P-47 and P-38. If you look at average partroling altitudes for Navy planes from historical account's they normally were not in that 14k to 19k if they could help it   I think 12k and below and 20k and above, right?

The P-47 produces much more power in that range, maintaining it's climb rate pretty well up to 25k or so when it starts dropping off slowly. Same with the P-38.

- Jig

[This message has been edited by Jigster (edited 09-20-2000).]

Offline StSanta

  • Gold Member
  • *****
  • Posts: 2496
The 1.05 planes
« Reply #24 on: September 20, 2000, 07:05:00 PM »
An attempt to be funny  .

Please don't hold it against me; I had a rough childhood. My Life manual wasn't in my package, and I've been pushing buttons ever since, trying to figure the damned thing out.

If you hated that one, yer gonna love this  

--
StSanta
JG54 "Grunherz"
 
"What is better, to be loved by one, or hated by all?"

Offline Sundog

  • Silver Member
  • ****
  • Posts: 1781
The 1.05 planes
« Reply #25 on: September 20, 2000, 11:14:00 PM »
In regards to the Hellcat's roll rate, I believe the spring tab ailerons were added in the -5 to offer a much better rate of roll, however, it never did match the F4U's roll rate. I think somewhere further back on the boards I posted a response regarding this subject based on reports from Corky Meyer, a Grumman Test Pilot. This is probably from the `Report of Joint Fighter Conference' book that Pyro recommended a while back. It's a good book with background information on the various aircraft you won't find in your average book on World War Two planes.


[This message has been edited by Sundog (edited 09-20-2000).]

funked

  • Guest
The 1.05 planes
« Reply #26 on: September 21, 2000, 07:48:00 AM »
Ripsnort:

I don't know where you got those weights.

Loaded weights (max internal fuel and ammo, no external stores) are about 12,700 lb for the Hellcat, 12,000 lb for the Hog, and 14,500 lb for the Jug.  Empty weights are interesting but I've yet to see any flight test data that was measured at the empty weight.  

The engines are different.
F4U-1D (R-2800-8W) and F6F-5 (R-2800-10W) both had 2135 hp with water injection.  The P-47D-27 through -40 (R-2800-59) could make 2600 hp with water injection.

The big difference is that Navy planes had two-stage two-speed mechanical blowers while the Jug used a single-speed single-stage mechanical blower plus a turbosupercharger.

The Jug's supercharging system could generate more boost at sea level than that of the Navy planes and could maintain that boost at high altitudes where the mechanical superchargers were gasping.

As a result the 2600 hp in the late P-47D could be maintained up to 25,000 feet, while the Hog and Hellcat could only maintain their 2135 hp ratings up to about 15,000 feet.

[This message has been edited by funked (edited 09-21-2000).]

funked

  • Guest
The 1.05 planes
« Reply #27 on: September 21, 2000, 07:51:00 AM »
DOA the reason the Jug benefitted more from water injection is because its supercharging system could generate more boost.  Water injection doesn't give you any more boost, it just lets you operate at boost levels that would normally cause detonation, overheating, and other bad things.

Offline Westy

  • Gold Member
  • *****
  • Posts: 2871
The 1.05 planes
« Reply #28 on: September 21, 2000, 09:47:00 AM »
Here:
 http://www.history.navy.mil/branches/hist-ac/f6f-5.pdf

Enjoy  

BTW. Are we going to have an armament option? This plane could have either two 20mm with four 50's or six 50's. *Another plane with hispanos. Fishu is going to go crazy!  

  -Westy

[This message has been edited by Westy (edited 09-21-2000).]

Nath-BDP

  • Guest
The 1.05 planes
« Reply #29 on: September 21, 2000, 10:51:00 AM »
The only F6F witn 20mm was the F6F5N, which was a nightfighter.