Fighter speeds at 10,000 feet

[Widewing]

We've seen several tests that established fighter speeds on the deck. We also seen a lot of testing at medium and high altitudes.

What we don't have is testing at altitudes commonly found in the MA. Therefore, I decided to record speeds for all fighters at 10,000 feet ASL.

Testing would be done with fuel loads that provide for between 25 and 35 minutes of flight time at Military power (max power, no WEP). All test aircraft were so loaded. Maximum internal ammunition loads were carried. Where external guns are offered (Bf 109s), they were not taken. No bombs or bomb racks were installed. Aircraft were flown from a 10k field to eliminate climbing and the corresponding waste of time. All speeds were CAREFULLY MEASURED using E6B. All aircraft were within 50 feet of target altitude. Only max speeds were recorded. That means WEP was used where it was available. Additional data from recent testing is included for the fastest 8 fighters.

Here's the results.

1) Bf 109G-10: 411 mph (429 mph @ 16k, 443 mph @ 25k)
2) P-51D: 406 mph (407 mph @ 16K, 441 mph @ 25k)
3) Fw 190D-9: 405 mph (417 mph @ 16K, 425 mph @ 20k)
4) Spit XIV: 404 mph (441 mph @ 25k, 444 mph @ 28.5k)
5) P-51B: 401 mph (424 mph @16K, 443 mph at 27.6k)
6) P-47N: 399 mph (476 mph @ 30k)
7) F4U-4: 398 mph (439 mpg @ 20k, 446 mph @ 25k)
8) Tempest: 396 mph (424 mph @ 16k)
9) La-7: 394 mph
10) F4U-1: 390 mph
11) Yak-9U: 387 mph
12) Ta 152: 386 mph
13) Typhoon: 381 mph
14) F4U-1C: 380 mph
15) F4U-1D: 380 mph
16) Bf 109G-2: 380 mph
17) P-47D-11: 377 mph
18) La-5FN: 377 mph
19) P-47D-40: 375 mph
20) P-47D-25: 374 mph
21) P-38J: 373 mph
22) P-38L: 373 mph
23) Bf 109G-6: 371 mph
24) Ki-84: 367 mph
25) Fw 190A-5: 366 mph
26) Fw 190A-8: 366 mph
27) Mosquito MkIV: 366 mph
28) Fw 190F-8: 365 mph
29) Bf 109F-4: 365 mph
30) C.205: 365 mph
31) Spit IX: 362 mph
32) P-38G: 359 mph
33) N1K2-J: 357 mph
34) Spit V: 355 mph
35) Seafire: 355 mph
36) F6F-5: 354 mph
37) Yak 9-T: 352 mph
38) Ki-61: 352 mph
39) C.202: 349 mph
40) Bf 110G-2: 343 mph
41) P-40E: 337 mph
42) Spit I: 331 mph
43) Bf 109E-4: 330 mph
44) A6M5b: 330 mph
45) Bf 110C-4b: 323 mph
46) P-40B: 313 mph
47) FM-2: 311 mph
48) Hurricane IIC: 311 mph
49) A6M2: 308 mph
50) F4F-4: 302 mph
51) Hurricane I: 300 mph
52) Hurricane IID: 293 mph

Note that the F4U-1 is 10th fastest fighter, a full 10 mph faster than the -1C and -1D. If you are wondering why the P-51D is no faster at 16k than it was at 10k, just look at the speed chart below.



My regards,

Widewing

[Furball]

so THATS why i couldnt catch those dastardly 109's in my Hurricane IID.

gj

[Krusty]

Furball, might want to disable the "Optional Drag Inducing" feature on the factory-fresh HurrD's... You see by removing the super clunky and super heavy (but mostly useless) pods under the wings, you will find you have much better performance! And reducing the guns from 8x303cal to 2x303cal means you're lighter than ever!!!

[Wotan]

10k feet isn't a good place to be in a 190. The sc switches gears around that alt and you will see a dip in performance...

[Widewing]

Originally posted by Wotan
10k feet isn't a good place to be in a 190. The sc switches gears around that alt and you will see a dip in performance...

Yep, same problem for the P-51D.

I always seem to forget how potent the P-51B is. At 16k, only the 109G-10 can out-run it. Even at 10k, it's faster than the much ballyhoo'd Tempest. At 16k it's dead even, with climb and acceleration virtually the same too.

When we take the P-51B and Tempest up to 20k, we see that the Tempest has a slight speed edge (425 mph vs 420 mph for the P-51B) solely the result of the P-51B being at supercharger shift altitude.

Nonetheless, the B-stang accelerates faster and was climbing considerably faster when they reached 20k (2,900 fpm vs 2,250 fpm for the Tempest). Testing the Dora at 20k as well, we see it is as fast as the Tempest (425 mph), but has no climb or acceleration advantage over the P-51B. (fuel was 50% for P-51B, 75% for Tempest and 190D-9).

Acceleration at 20k, 200 mph TAS to 300 mph TAS. Timing from 200 mph using E6B for speed.

P-51B: 31.87 seconds
190D-9: 34.66 seconds
Tempest: 38.75 seconds

It's too bad the B-stang has only four machine guns. I wonder what would have happened had the production planes retained the 4 Hispanos of the XP-51B....

My regards,

Widewing

[J_A_B]

If you test them at 30K you will see the P-51B is a monster up there.

"It's too bad the B-stang has only four machine guns. "

Optionally, you might wonder---as many pilots wondered--why the heck they switched to the V-1650-7 with its lower alt supercharger.  



J_A_B

[Magoo]

Dont be too hard on the B's gun package. Let's keep in mind that one of the reasons the B-stang handles better is because it only has 4 guns in the wings.  Kind of the same reason why I take the 6 gun/low ammo option up in a Jug very often.

Have you fellows noticed the dramatically increased use of the B in the MA? Seems every other Pony I see now is a B. Likely that a fellow tries it out because of the new Malcolm hood only to find that it handles wonderfully and as we are discussing...is uber (4 x 50s be damned).

I guess the friggin' cat is out of the bag.

On a related note, did you know you can take the 4 X 50 option on the 51D and carry substantially more rounds total than the 6 x 50 package?

Magoo

[J_A_B]

"On a related note, did you know you can take the 4 X 50 option on the 51D and carry substantially more rounds total than the 6 x 50 package? "

It's a similar number of rounds, just divided between 4 guns instead of 6.  With the 6 gun package you carry 1880 rounds.  2 guns have 400 rounds, and 4 guns have 270 rounds.  With 4 guns, you carry 1800 total.  Two guns have 400 and two have 500.  The way the ammo boxes in the P-51D were laid out, if you removed one of the guns then the outer .50's could use the all of outer wing boxes for ammo.

I think the P-51B carries something like 1260 rounds, give or take a few (my memory is a little fuzzy).

J_A_B

[stantond]

Firstly, I would like to thank Widewing for taking the time and energy to document the current plane speeds at 10k.  That is usually the altitude I fly at in the MA.  I have found with 10k alt there are multiple evasive maneuvers available from attacking planes and its a good altitude to attack from.

As an aside, when the day comes that I can consistently kill with the B's four 50's I'll be elated!  Until then, the Malcom hood is good (but not that good).  When I flew ponies more, the D model could out perform and out maneuver the B model.  Don't think that's changed.  

In order to land enough hits for a kill you usually need to slow down to saddle up and the B is not a slow speed plane.  The ammo load out is low also.  However, the B model is a relatively fast plane.

That said, I'll probably keep flying it to help force me to pick better shots.  Too bad assists don't count for anything.  


Regards,

Malta

[J_A_B]

"When I flew ponies more, the D model could out perform and out maneuver the B model. Don't think that's changed. "

This should be true at very low altitudes, because the P-51D's engine develops considerably more power down low (different supercharger gear ratios).  At higher altitudes, the P-51B will hold a substantial advantage.

I never really noticed much difference between the 4 and 6 gun package for killing power, with the result being that I often took 4 guns in the P-51D.  I tended to rely on solid tracking shots and didn't really make much use of snapshots (I hated wasting ammo).  

J_A_B

[Bronk]

I think the reason for more P-51B use is ........



The malcom hood. that is the single best thing they did when they upgraded the 51's.    











Bronk

[Magoo]

I stand corrected J_A_B. I did the (erroneous) math in my head when I added it up. The good news is you do get much more fire time albeit at a reduced punch. As far as the 4 x 50s in either model, I try to pick my engagements or drag and bag, hopefully not with a T&B plane, but in that environment the 4 x 50s are sufficient. Usually the 1st hit you can knock some parts off and work your opponent from there. In a furball your gonna have to accept more assists since you don't have the 1 pass knockout power.

As far as the B model performance compared to the D: Yes the D is faster on the deck and the B faster up hi, but I also find the B to be much more responsive in a turn or roll at equal fuel loads and it seems even the maneuvering flaps give you more lift in the B model. I don't think the 4 gun 51D even compares. I may test this one day, for now it's based on feel.

Magoo

[Karnak]

Bf109G-10 best alt should be about 22,000ft.

Spit XIV best alt should be about 27,000ft.