High alt acceleration and speed

[Widewing]

When Combat Tour debuts, the first scenarios will revolve around the ETO, probably focused on 1944.

With that in mind, I thought it might be fun to see how the various American and German fighters will perform at altitudes above 20,000 feet.

Therefore, I did some simple tests of a limited number of aircraft. I recorded acceleration at 20k and 25k as well as max speed at 25k in MIL power and WEP.

All aircraft were loaded with 25% internal fuel. This was done to reduce climb time. To futher minimize time required to reach altitude, I took off from a 10K field. Acceleration will be faster at the lighter weight, but max speed will only be a few mph faster. Fuel burn was zero.

Acceleration was measured from 200 MPH TAS to 300 mph TAS. 200 mph TAS is the minimal practical air speed as 150 mph TAS is too slow for these altitudes. As it was, the Dora was nearly stalled at 200 mph TAS. Times are in seconds.

Data: Time to accelerate @ 20k / Time to accelerate @ 25k / Max Speed MIL @ 25k /Max Speed WEP @ 25k

Bf 109G-6: 36.12/45.41/382 mph/388 mph

Bf 109G-14: 32.53/43.53/383 mph/391 mph

Fw 190D-9: 37.83/46.22/417 mph/423 mph

P-38J: 33.28/38.07/403 mph/420 mph

P-47D-25: 34.69/37.88/416 mph/430 mph (432 mph @ 30k)

P-47D-40: 34.22/36.72/416 mph/432 mph (435 mph @ 30k)

P51D: 36.04/43.53/431 mph/441 mph

It's interesting that the P-38J and the Jugs accelerate faster than the P-51D. Likewise, the 109s and Dora cannot hope to run away or climb away from the American hardware up at 25k. Their only avenue of escape is to split-s and dive. They won't dive away from the Jugs or Mustang, but the P-38J could not follow without serious compressibility issues.

You can see that the 109G-14 offers good acceleration at 20k, but  acceleration, speed and climb rate fall off quickly above that altitude. Indeed, there's no great difference between the 109G-6 and the 109G-14 at 25k.

My regards,

Widewing

[Warspawn]

Great work!  So, assuming 1944 ETO, much of the scenarios will revolve around bombers and their escort intercepts?  If so, this will be a chance to illustrate the frustration the Luftwaffe had to deal with as their hardware became inadequate to deal with the task assigned to them (stopping the bomber raids over the Reich).

Not going to be much fun for the LW, since their best chance to avoid engaging superior aircraft in the envelope they were designed for, will be to dive away from them (and away from the bombers they're supposed to be attacking).  Will K-4 and TA-152's be available, or were their numbers of production and time in service incompatable with the scenario?

[Bruno]

o/t but WTH:

The first CT tour should run from '43 to the end of the war.

As the tour progresses the later plane types will come online. There are some real problems with the plane set as is and their are huge gaps.

Despite those gaps planes like the 109G-6 (2-43) and 190A-5 (6-43) would be 'matched' against the D-11 (3-43 as D-5 sub) and P-38G (11-42) then the 38J and P-51b (12-43) would come online. With no 190A-6 or A-7 the best LW bomber killer would be the G-6 with gondolas making its performance even worse.

The A-5 has only 2 MG151/2cm. The MGFF as modeled in AH are weaker then the Japanese Type 99 MK 1 and are completely useless. No M'geschoss rounds are modeled and MGFF will contribute very little to the over all lethality of the the A-5. They aren't worth their weight. Not only that there are only 60 rpg despite the fact that in '43 a 90 round drum was available. The 90 round drum fit in the same space as the 60 round drum. The A-6 would have just about the same performance as the A-5 but could carry 4 x MG151/2cm and its lethality would be boosted greatly over the A-5.

The AH G-14 is poor choice for the CT 'WETO Bomber Camapign'. This was pointed out way back when the G-14 was announced. The G-14 was a great addition to AH and was requested for the longest time by me and others. However, the G-14 has a FTH of 16400 above that it is just slightly better then the G-6. It was requested that HTC keep the G-10 but with a modified performance. This way it could have stood in for th AS engined 109s. The G-6/AS, G-14/AS, G-10 and the K-4 all had the same supercharger from the DB603 and a higher FTH and better performance above 20k then what's available now (K-4 excluded).

The G-14 and G-14/AS saw service in June '44. The G-10 and K-4 in October '44. The G-14/AS and G-10 had close enough performance that the G-10 could have subbed for the G-14/AS.

The Dora entered service in Sept '44 but in AH the Dora is modeled with the performance of a later Dora, Jan '45.

So by entry dates, fighters only, LW in bold:


P-38G ... 11-42
Bf 109G-6 ... 2-43
P-47D-11 ... 3-43(D5)
Fw 190A-5 ... 6-43
P-38J ... 12-43
P-51B ... 12-43
Fw 190A-8 ... 2-44
P-47D-25 ... 5-44
P51D ... 5-44
P-38L ... 7-44
Bf 109G-14 ... 7-44
Bf 109K-4 ... 10-44
P-47D-40 ... 1-45
Fw 190D-9 ... 1-45

With just a few minor aircraft inclusions the first CT tour would have had a great series of match-ups.

For example a P-47C (not retro-fitted), a Fw 190A-6 and a G-10 with rl G-10 performance standing in as an AS engined Gustav and things would have been perfect as far as I am concerned. As such it is what it is...

I am curious to see how the numbers balance out once the CT goes gold. Since the AH player base prefers Ami planes by far lets hope the AI is competitive enough to give them a fight.

[Angus]

This:
"Not going to be much fun for the LW, since their best chance to avoid engaging superior aircraft in the envelope they were designed for, will be to dive away from them (and away from the bombers they're supposed to be attacking). "

Well, it was pretty much slashing attacks, and the escape was downstairs.

Look at how good the P47's are when it comes to 25K BTW. And then yet we are to see how it looks like at 30K!! (High escorts).

For the hell of it, it would be fun to see how a Spit IX would do up there.

Oh, and Bruno, do you have some wee more on the G10 (intro date) and then the 190A6. Were they available in big numbers?

[TexMurphy]

would be interesting to see some manouverability stats... such as turn radious and loop radious of these planes at this alt...

Tex

[bozon]

Originally posted by Widewing
All aircraft were loaded with 25% internal fuel. This was done to reduce climb time.

.wind 0 0 0 100
and ride a 100mph thermal wind

It's interesting that the P-38J and the Jugs accelerate faster than the P-51D. Likewise, the 109s and Dora cannot hope to run away or climb away from the American hardware up at 25k.

Superchargers RULE!
This is where being big and fat to accomodate all the tubes and ducting of the superchargers starts to pay off. It will be nice to run down 109s and out climb 190s with the jug instead of the other way around.

Originally posted by Bruno
The G-14 and G-14/AS saw service in June '44. The G-10 and K-4 in October '44. The G-14/AS and G-10 had close enough performance that the G-10 could have subbed for the G-14/AS.

Will be interesting to see some service numbers. Do you happen to know how common were the AS models on the western front?

Bozon

[Kev367th]

Originally posted by Angus
Look at how good the P47's are when it comes to 25K BTW. And then yet we are to see how it looks like at 30K!! (High escorts).

For the hell of it, it would be fun to see how a Spit IX would do up there.

 

IX with the Merlin 61 (ours) should be somewhere around these ballpark figures (no slouch for 1942)-

385 m.p.h. at 15,000 ft.  
409 m.p.h. at 28,000 ft.  
394 m.p.h. at 30,000 ft.

A Merlin 70 one is approx 10-20mph faster at alts over 15k. i.e. 395 @ 15k up to 414 @ 30k.

[Bruno]

Angus,

Oh, and Bruno, do you have some wee more on the G10 (intro date) and then the 190A6. Were they available in big numbers?

G-10 entered service in October '44.

There were more A-6s produced then A-5s. The A-6went into production in June '43. LW a/c usually went from production to service within a month. In Fact JG2 had A-6s in July '43. The A-5 date above is wrong. It entered production in Feb '43 and for example JG2 recieved A-5s in March '43.

the biggest difference in terms of AH and CT is that the A-6 could carry 4 x MG151/2cm giving it better fire power against bombers then the A-5.

bozon,

Do you happen to know how common were the AS models on the western front?

There were around 5000 G-14s produced with about 1000 being G-14/AS. G-14/AS entered service with II/JG 27 and I/JG 77 in Aug '44.

The G-6/AS entered service in May '44 with JG 1, JG 5 and JG 11. I don't recall G-6/AS production numbers. AFAIK all the AS engined 109s were used in the west. Due to the larger SC their low altitude performance was not as good. For example the standard G-14 was faster at SL then the G-14/AS.

[Bruno]

G-6/AS = +/- 700-800 produced
G-14/AS = +/- 1000
G-10 = +/- 2600 produced

updated service entry dates:

P-38G ... 11-42
Bf 109G-6 ... 2-43
Fw 190A-5 ... 3-43
P-47D-11 ... 3-43(D5)
P-38J ... 12-43
P-51B ... 12-43
Fw 190A-8 ... 4-44
P-47D-25 ... 5-44
P51D ... 5-44
P-38L ... 7-44
Bf 109G-14 ... 7-44
Bf 109K-4 ... 10-44
P-47D-40 ... 1-45
Fw 190D-9 ... 1-45

[DoKGonZo]

Did you run those tests on all planes or just the ones for CT?

[Widewing]

Originally posted by DoKGonZo
Did you run those tests on all planes or just the ones for CT?

Just those. It comsumes a lot of time climbing. However, Hammer just forwarded me a new map with 20k bases. So, I can do more much faster now.

I will try to flesh-out the whole fighter set over the next week or so.

My regards,

Widewing

[Murdr]

Nice work on this and the sea level acceleration.  Thanks.

[Karnak]

I have always used the

.wind 124 124 124 0

command to climb fast.

Then the

.wind 0 0 0 0

to set the wind back to nothing.

[1K3]

hmmm also note our 190A-5 is a bit too fast at alt and bit too slow at deck.  The A-5 also climbs waaay too fast, it even has higher ROC than the actual german climb test.  I wonder where HTC got the speed/climb figures for Fw 190A-5...

[Debonair]

I wonder if accelerating out of the "back side of the power curve" might be accomplished more swiftly by not doing it in level flight