Author Topic: speed test, climb test (Read 580 times)

-ammo- · « **on:** September 16, 2002, 08:31:53 PM »

All this about AC performance prompted me to do some test's in AH. Now mind you, this is in game test, not real life data. How it compares to real life data is not my problem:) I tested six AC, the P-51D, the FW 190D, the TA-152, the Spit9, the spit14, and the P-47D30. I only ran comparisions for max climb, and max speed. To keep it as simple as possible, I tested at 25K and 30K. Now, its very rare that a fight in AH is held at that altitude, but I wanted to see how AH AC stacked against each other at those altitudes. I was surprised.

25K

30K

a couple of things stand out for me. First, which spit is the hotrod?

Second, the P-51D is nowhere close to what it should be doing at 30K, about 20-30 MPH short by the data I have seen lately. Please reference the P-51 post here http://216.91.192.19/forums/showthread.php?s=&threadid=64200&perpage=50&pagenumber=3

Its climb rate is rather slow as well in comparison.

he TA 152 has awesome speed at 30K, wilbuz will tell us if it is up to par;)

Nothing outclimbs a spit9 at this alt. (exception could be the 109G10), even the spit14 takes a back seat.

GRUNHERZ · « **Reply #1 on:** September 16, 2002, 08:36:33 PM »

Well everyone knows the SpitIX was the best performing fighter of the war.....

ra · « **Reply #2 on:** September 16, 2002, 09:22:54 PM »

The Jug's engine was better above 25K than the P-51's. The P-51 maxed out at around 24K, the Jug at 30K. At 30K the Merlin only produced around 900 HP.

ra

thrila · « **Reply #3 on:** September 16, 2002, 09:25:14 PM »

The spit F IX does that well because it's suposed to. But hey, i wont argue if you want the Spit LF IX modelled instead.

Spitfire F mk IX

-ammo- · « **Reply #4 on:** September 16, 2002, 09:59:07 PM »

OK thrila, I can exept that, but is the spit14 supposed to be better at 25 and 30K?

-ammo- · « **Reply #5 on:** September 16, 2002, 10:01:37 PM »

Quote

Originally posted by ra
The Jug's engine was better above 25K than the P-51's. The P-51 maxed out at around 24K, the Jug at 30K. At 30K the Merlin only produced around 900 HP.

ra

actually, the P-51D published speeds at 29-30 K are much better than what I got in my test.

I won't argue ythat the P-47 had a better engine (induction system) than the P-51 at alt, I agree. Just that the numbers dont match.

J_A_B · « **Reply #6 on:** September 16, 2002, 11:07:24 PM »

AMMO, the reason the P-51 does so poorly is you're using the wrong model. You used the P-51D (V-1650-7 engine) in your tests; the published data you quoted in that other thread was a P-51B with the V-1650-3 engine.

The difference between the two engine types was that in the -7 engine the gear ratio of the supercharger was reduced which resulted in the engine having a lower critical altitude; this meant that P-51D's and late-model P-51B's had worse performance at very high altitudes than the earlier P-51B's. Why they made that engine change is beyond me; I've never heard of a good reason for it. This engine difference is reflected in AH; the P-51D maxes out at around 25K but the P-51B maxes out at around 28-29K.

Test the AH P-51B instead of the D and it should match your info much better.

J_A_B

Karnak · « **Reply #7 on:** September 17, 2002, 01:15:43 AM »

Spit XIV should hit its maximum speed at about 26,500-27,000ft on WEP, a speed of 448mph.

The Spit XIV without WEP is a rather mediocre and disappointing fighter, which is why I keep pointing out in the "perk threads" that you're paying all 60 points for the five minutes of WEP. If you look at the Spit XIV's AH charts you'll see that it gains a bigger boost to its performance from WEP than any other aircraft in AH and without WEP it is unimpressive. That's why a WEPless Spit XIV is a Spit XIV in serious trouble.

-ammo- · « **Reply #8 on:** September 17, 2002, 05:38:44 AM »

So..It's normal for a spit9 to outclimb a spit14 at 25k? All test were ran with 50% fuel (offline with 0 fuel modifier) with WEP engaged?

niklas · « **Reply #9 on:** September 17, 2002, 05:41:31 AM »

Quote

Originally posted by J_A_B

The difference between the two engine types was that in the -7 engine the gear ratio of the supercharger was reduced which resulted in the engine having a lower critical altitude;
...
This engine difference is reflected in AH; the P-51D maxes out at around 25K but the P-51B maxes out at around 28-29K.
J_A_B

yep, and the -7 run also with higher boost right? This too reduces the critical altitude, the engine will reach the limit for +18lb earlier than for +16lb.

The 25k claim for the -7 doesn´t seem to be corrected for standard day conditions btw. Those are the critical altitudes for the engines without RAM effect, and with it, assuming a gain of 3000ft:
V-1650-3
1st gear: 15750ft / 18750ft
2nd gear: 26500ft / 29500ft
V-1650-7
1st gear: 5100ft/ 8100ft
2nd gear: 18500ft / 21500ft

While it sounds very realistic that the P-51B was fastest at 30k, the topspeed for the D model in 25k sound unrealistic for standard day conditions. And this is confirmed by this chart where "400mph RAM effect" is already included, concerning critical altitude. The -D should top out at 21k probably.

niklas

Wilbus · « **Reply #10 on:** September 17, 2002, 06:31:58 AM »

Hey ammo

The Ta152 is up to par IF it was an H-0, we have the H-1 (or so the hanger and webpage says and the weight and the wing tanks).

So speed matches the H-0 pretty good, almost perfect actually, but are way of as we're suposed to have the H-1

But yeah, it's a fast plane above 30k, only the P51 B can match it.

Wilbus · « **Reply #11 on:** September 17, 2002, 07:31:02 AM »

Tests for P51 B using 50%.

31k: 335mph no wep
338 mph wep

33k: 430 mph no wep
no increase.

35k: 421 no wep
no increase

30k: WEP, after dive, deacceleration with wep didn't go lower then 447mph.

Acording to the charts we have on AH webpage now it should reach around 440-445 at 29,5k, seems to be right.

Bombjack · « **Reply #12 on:** September 17, 2002, 07:32:20 AM »

Quote

OK thrila, I can exept that, but is the spit14 supposed to be better at 25 and 30K?

Yes it is. According to the AFDU tests on MW's site, it breaks down like this:

25k Climb Rate (fpm)

Spit IX ammo: 2950
SpitXIV ammo: 2600

Spit IX AFDU: 3020
Spit XIV AFDU: 3100*

* averaged from 24k and 26k figures

30k Climb Rate (fpm)

Spit IX ammo: 2000
Spit XIV ammo: 1800

Spit IX AFDU: 2280
Spit XIV AFDU: 2390

On to the level speeds...

25k Max Level Speed

Spit IX ammo: 409
Spit XIV ammo: 434

Spit IX AFDU: 391
Spit XIV AFDU: 446*

* speed measured at 25,400 feet

30k Max Level Speed

Spit IX ammo: 398
Spit XIV ammo: 419

Spit IX AFDU: 402
Spit XIV AFDU: 443

*edit*

Note that the AFDU tests were all conducted with a full fuel load.

thrila · « **Reply #13 on:** September 17, 2002, 09:07:56 AM »

Isn't that interesting.......the spit XIV is porked at high alt. Not just speed as above but, in climb too.
spitXIV

-ammo- · « **Reply #14 on:** September 17, 2002, 05:19:28 PM »

rgr that on the spit14, it isnt the monster at that alt I thought it would be.

BTW, I tested all the AC with 50% fuel load with no fuel modifier. So, it was still 50% when I tested at alt.