Fw-190 Dora-9 vs P-51D Mustang

[paul.kachurak]

Syscom3,

Yes it would be nice but it is also nice to see it in German because IMO it enhances it's authenticity. Do you have any questions on those two? I've used this site http://dict.leo.org/?lang=en&lp=ende&search= to translate a lot of it and the rest I've figured out what it is on my own. German is a tricky language.

To convert from kilograms to pounds mulitply kgs by 2.204623
To convert from meters to feet multiply meters by 3.28084
To convert from square meters to square feet well multiply by the square of 3.28084
To convert from kilometers per hour to miles per hour multiply kph by 0.6213712

I can tell you this from my school days it is a heck of a lot easier working in metric than in US units.

[Lunatic]

Originally Posted by KraziKanuK

Is that with or without dts?

As you can see, the P-51 was capable of a 425 mph cruise with a range on internal fuel (as specified) of 850 miles.

What is dts?

=S=

Lunatic

[FLYBOYJ]

Originally Posted by Lunatic

As you can see, the P-51 was capable of a 425 mph cruise with a range on internal fuel (as specified) of 850 miles.


=S=

Lunatic

Great chart, but are you saying that the -51 "cruises" at this setting (at 30,000 feet)? The way I read that chat it's showing Max. Continous, (97GPH) 2700 RPM. "Cruise" or an econmical setting would be on the far right and a lot lower, and the airspeed is TAS not indicated. If converted to indicated, (depending on temp & density altitude) it would be a lot lower....

[KraziKanuK]

The Spit has a TAS of 314mph @ 20k' which is 235mph IAS turning 2650rpm.

If my math is correct, then the P-51 had a IAS of 318mph at the same altitude, some 72mph slower than the shown TAS.

[Lunatic]

Originally Posted by wmaxt

Cruise speeds are always dependant on range issues The P-51 cruised at about 260mph for max endurance/reasonable speed and according to a P-51 pilot who flew out of England durring the war thats what they flew at. However a pilot that flew with the checkertails out of Italy said that they frequently flew at 350/360mph cruise but NEVER faster than that unless they were in attack mode "It used to much fuel" Quote and italics are his.

My TO-1 states Max endurance at 140mph CAS
Max range Wing racks only 35,000ft 66gph 367mph but at 10,000ft its 261mph and 42gph. Our checkertail friend stated they used 55/60 gph to define/limit/optimize their cruise speeds.

My TO-1 Mustang handbook states Full Throttle (military) for a P-51D is 424mph. All stats and tests I've seen rate the P-51 D at 420s in military or 1,590hp and 437mph at 1,650hp in WEP. The P-51B/C was about 3 mph faster. The 1 test I've seen with a P-51 in the 450mph range was 'cooked' The aircraft was well over 1,000 lbs lighter than normal test weight and probably prepared in other ways because this was a max possable test not a comparison test.

wmaxt

That's BS. I have the test report and the P-51B tested, AAF serial # 37050, was at 9423 lbs takeoff weight - fully loaded clean condition. The only change from production on the plane was a reworking of the radio antenna which was a standard field change usually applied before the planes were delivered to combat units. Maximum speed, 351 mph TAS, was determined at 3000 rpm and 67" of manifold pressure at ~29000 feet.

And if anything the USN report is biased against the P-51B and in favor of the F4U-1 and -1a used in the test.

[Lunatic]

Originally Posted by FLYBOYJ

Great chart, but are you saying that the -51 "cruises" at this setting (at 30,000 feet)? The way I read that chat it's showing Max. Continous, (97GPH) 2700 RPM. "Cruise" or an econmical setting would be on the far right and a lot lower, and the airspeed is TAS not indicated. If converted to indicated, (depending on temp & density altitude) it would be a lot lower....

The chart is right out of the P-51D pilot handbook. The brownish highlighting with rounded boxes is the handbook example, which shows a 325 mph cruise at 10,000 feet yeilds an 1100 mile range, after climbout (which is covered on the previous page). The left column shows the maxium speed continous cruise possible, and each colum to the right shows a progressively longer range cruise at a lower power rating.

Notice that at 30,000 feet at 2450 rpm and full throttle hight in the run condition the P-51 can managed 1220 miles after climbout.

Of course indicated air speed would be lower at altitude, but that is true for every plane equally right? Top speed and cruise speed figures are almost always given in TAS.

=S=

Lunatic

[FLYBOYJ]

Originally Posted by KraziKanuK

The Spit has a TAS of 314mph @ 20k' which is 235mph IAS turning 2650rpm.

If my math is correct, then the P-51 had a IAS of 318mph at the same altitude, some 72mph slower than the shown TAS.

That sounds about right at standard temperature/ pressure (59F at seal level, 29.92).

[wmaxt]

Originally Posted by "Lunatic

That's BS. I have the test report and the P-51B tested, AAF serial # 37050, was at 9423 lbs takeoff weight - fully loaded clean condition. The only change from production on the plane was a reworking of the radio antenna which was a standard field change usually applied before the planes were delivered to combat units. Maximum speed, 351 mph TAS, was determined at 3000 rpm and 67" of manifold pressure at ~29000 feet.

And if anything the USN report is biased against the P-51B and in favor of the F4U-1 and -1a used in the test.

No BS (which I resent) the data is right out of the Pilots Handbook for the P-51D 1947 edition.

Then I haven't seen the report you are refering to. The report I'm refering to had the P-51 at a weight listed below 8,000lbs and was not being compared to anything. I have looked but not found any tests or specs on the P-51 that indicate otherwise - that does not mean they don't exist - I haven't found or seen them. The other thing is that specs on the P-51 are very consistent even from Mustang advocates, if the P-51 was normaly faster (and 10/12mph is significant) than reported surely we would be hearing about it?

Flyboy, is also correct, Max Continous, is not cruise and according to the pilots I contacted they flew cruise at 55/60gal/hr 250/260IAS ~360TAS (I think thats high for TAS) @ ~25,000ft, and he made a point of stating, in italics, that anything faster than that used to much fuel for anything but actual combat. Three-sixty is substantial and better than almost every one else. I also posted the max range numbers which lists 367mph @ 35,000ft 66gph and 261mph @ 10,000ft both numbers TAS. The Pilot I contacted that flew out of Britian flew 250mph (I assume IAS) on missions over Germany including sweeps.

I repeat, I've only shown or commented on data I have, with no additions, modifications or adjustments.

wmaxt

[Udet]

Mr. Lunatic:

I´ll get back to you later on this, sorry.

[FLYBOYJ]

Originally Posted by Lunatic

The chart is right out of the P-51D pilot handbook. The brownish highlighting with rounded boxes is the handbook example, which shows a 325 mph cruise at 10,000 feet yeilds an 1100 mile range, after climbout (which is covered on the previous page). The left column shows the maxium speed continous cruise possible, and each colum to the right shows a progressively longer range cruise at a lower power rating.

Notice that at 30,000 feet at 2450 rpm and full throttle hight in the run condition the P-51 can managed 1220 miles after climbout.

Correct! I thought you were suggesting that the chart on the lower left (where you got the 425 mph) was a cruise chart. Big difference in fuel flow!!!

Originally Posted by Lunatic

Of course indicated air speed would be lower at altitude, but that is true for every plane equally right? Top speed and cruise speed figures are almost always given in TAS.
Lunatic

Actually indicated airspeed would match closer to TAS at lower altitudes if air temp and pressure a standard (29.92, 15C).

here's some rough examples.
Pressure Altitude S/L OAT +15c IAS 300MPH TAS 300
Pressure Altitude 5000' OAT 0c IAS 300MPH TAS 319
Pressure Altitude 10000 OAT -20C IAS 300MPH TAS 332
Pressure Altitude 20000 OAT -40C IAS 300MPH TAS 395
Pressure Altitude 30000 OAT -60C IAS 300MPH TAS 463

[Jabberwocky]

2700 RPM and 46" manifold are the "maximum continious" settings according to the P-51 Pilots Operations Handbook. That means that as long as the coolant and oil temperatures stayed within parameters (100-121 degrees for coolant and 70-105 degrees for oil) the engine could be held at that setting indefinately.

[FLYBOYJ]

Originally Posted by Jabberwocky

2700 RPM and 46" manifold are the "maximum continious" settings according to the P-51 Pilots Operations Handbook. That means that as long as the coolant and oil temperatures stayed within parameters (100-121 degrees for coolant and 70-105 degrees for oil) the engine could be held at that setting indefinately.

Yep, but you wouldn't want to stay there if you're trying to save gas!

[Lunatic]

Originally Posted by wmaxt

No BS (which I resent) the data is right out of the Pilots Handbook for the P-51D 1947 edition.

Then I haven't seen the report you are refering to. The report I'm refering to had the P-51 at a weight listed below 8,000lbs and was not being compared to anything. I have looked but not found any tests or specs on the P-51 that indicate otherwise - that does not mean they don't exist - I haven't found or seen them. The other thing is that specs on the P-51 are very consistent even from Mustang advocates, if the P-51 was normaly faster (and 10/12mph is significant) than reported surely we would be hearing about it?

Flyboy, is also correct, Max Continous, is not cruise and according to the pilots I contacted they flew cruise at 55/60gal/hr and he made a point of stating, in italics, that anything faster than that (~360mphTAS at ~25,000ft) used to much fuel for anything but actual combat. Three-sixty is substantial and better than almost every one else. I also posted the max range numbers which lists 367mph @ 35,000ft and 261mph @ 10,000ft both numbers TAS.

I repeat, I've only shown or commented on data I have, with no additions, modifications or adjustments.

wmaxt

My appologies, I didn't mean to offend you wmax, "BS" is considered very mild in my current environment.

Here's the report... (these are gifs so they should be small enough not to take too long to upload).

=S=

Lunatic

[Soren]

Originally Posted by Erich

intersting just checking through data on the engines of the Ju 88G-6. not bad for an old hunk of bolts. 2 Jumo 213E's with 1,880 h.p. up to 2,250 h.p. rating when needed...............
E ~

Yeah, and if im not entirely mistaken the Dora-13 (Which saw service btw), used just that engine.

Suddenly 2,240 HP from the Jumo 213A doesn't seem so unreal anymore, huh Paul ? You'd be surprised how much, switching from 87 to 100 octane fuel and adding a Compressor, actually increases the horsepower of an engine. (Not to mention having methanol sprayed into the engine at the same time as-well !)

Anyway Paul, I'll get back to you about the Jumo 213A later, as Im in abit of a hurry right now.

[wmaxt]

Originally Posted by Lunatic

My appologies, I didn't mean to offend you wmax, "BS" is considered very mild in my current environment.

Here's the report... (these are gifs so they should be small enough not to take too long to upload).

=S=

Lunatic

Thanks for the test. Though I try hard to be both correct and neutral, I do make mistakes once in a while, I also understand a little fanatisim too (Obviously I'm suseptable sometimes to).

I see the 450mph but I also note the wing was prepped "sanded smooth" If it was sanded then it would also have been buffed giving it a polished finish easily increasing speed of the aircraft.

I would like you to reference this site:
http://yarchive.net/mil/laminar_flow.html
which sums up what I've come to understand as the real life results of the P-51s unique features and performance. Included is a test of the P-51B @ 448mph but again its noted that the aircraft is not quite field standard.

IMHO, the P-51B/C/D/K was a very good aircraft by 1944/45 standards but not really a stand out except for range. Tactics and numbers made it a great plane. It traded Climb, and maneuvering for range and speed not to say the compromise wasn't good but it was compromised somewhat to do that. Like all planes it had some weaker points, but better training, support, and tactics compensated for those points quite a lot.

wmaxt