109 performance notes

[Krusty]

109 E4 rolls like a zero at 400 mph. So does the 109 K4. The 109 F4 rolls pretty bad until you start hitting 175mph, then it gets back to what it normally is (normally in AH anyways). I haven't noticd any change in G6 and G14 is almost just like G6 (flight-wise).

109E-4 still has short span slats. [EDIT: Changed to slats, I typed flaps originally]

So, what's up with the roll rates? Bug or change to reflect accurate roll rates??

109E is no longer the nimble zero it's been since AH2 came out.

[Karnak]

Bf109G-14 felt pretty dang nice to me, but I haven't tried it in combat.

[1K3]

i cant wait to see the 109F-4 vs Spit V re-match!:p

[1K3]

109G-14 climbrate is fantastic!  when i wa staking off the climb meter was at 3100, hit the wep then the climbrate went over 4K.  

note i was carrying 1/2 main tanks

[Grits]

Roll rate seems unchanged to me.

[justin_g]

G-14 seems to be too slow at higher altitudes.

Sea level - 317mph@1.3ata, 347mph@1.7ata = +30mph
16,000ft - 375mph@1.3ata, 390mph@1.7ata = +15mph

16,000ft is still below the critical altitude, so the speed gain should be similar to sea level, ie: G-14 should do 405mph at least!

[Nashwan]

Sea level - 317mph@1.3ata, 347mph@1.7ata = +30mph
16,000ft - 375mph@1.3ata, 390mph@1.7ata = +15mph

16,000ft is still below the critical altitude, so the speed gain should be similar to sea level, ie: G-14 should do 405mph at least!

That's down to the nature of the DB's hydraulic coupling, surely? (less power required to maintain a particular boost pressure at low level than high, 1.7 ata at sea level should require little from the supercharger with RAM)

[justin_g]

Hydraulic couple doesn't do anything at s/l, it kicks in at about 8000ft(lower if using MW50 boost, at about 3000ft) - and at critical altitude it's not doing anything again(~16400ft if using MW50 boost).

German charts show about 30mph improvement with MW50 boost up to critical altitude(see here - compare the pink and red curves).

[Bruno]

At 16k the G-14/AS, according to the chart you linked on Mike's site, does about 392 mph.

If the AH G-14 does 390 it may have the performance of the G-14/AS. What's the speed at 24.5k? 415mpg like the chart on Mike's page?

Even the deck speed, 347mph vs 342mph (see chart) is a bit low (352 for the G-6/R2 mph).

I haven't done any tests myself on AHs G-14, I will try to get to it later tonight.

[Kurfürst]

Originally posted by justin_g
G-14 seems to be too slow at higher altitudes.

Sea level - 317mph@1.3ata, 347mph@1.7ata = +30mph
16,000ft - 375mph@1.3ata, 390mph@1.7ata = +15mph

16,000ft is still below the critical altitude, so the speed gain should be similar to sea level, ie: G-14 should do 405mph at least!

Official figures for the (clean) G-14 maximum speed w. MW50 were 568kph/352mph at SL, and 665kph/413mph at 5000m/16400 feet.

Your data measured in the sim is well below the historical specs of the G-14, it's too slow.


Care needs to be taken with Mike's site, it doesn't list any 109 with full power, and it tends to cherry-pick from the worst results/data, often showing planes with external loads. The G-14/AS is one example, what Mike lists is a variant with external gunpods, not a clean one.

Official figures for the G-14/AS was 562kph SL, 680kph at 7500m.

[MiloMorai]

Originally posted by Kurfürst
Official figures for the (clean) G-14 maximum speed w. MW50 were 568kph/352mph at SL, and 665kph/413mph at 5000m/16400 feet.

Care needs to be taken with Mike's site, it doesn't list any 109 with full power, and it tends to cherry-pick from the worst results/data, often showing planes with external loads. The G-14/AS is one example, what Mike lists is a variant with external gunpods, not a clean one.

Official figures for the G-14/AS was 562kph SL, 680kph at 7500m.

If Mike did not state the ata for the a/c, the source of the data and that gondolas were fitted for the graph lines, then you would have a reason for your whines.

Mike states, "The GL/C-E2 for a clean G-14 with ASM engine gives 348mph(560kph) at Sea Level and 422mph(679kph) at FTH."

So you whine about a -2kph @ SL and and -1kph at altitude.

Hans Knickrehm of I./JG3 recalled the condition of new Me109G-14/AS's received by his group in Oct 1944:

The machines that were delivered were technically obsolete and of considerable lower quality. The engines proved prone to trouble after much too short of time, because the factories had had to sharply curtail test runs for lack of fuel. The surface finish of the outer skin also left much to be desired. The sprayed on camoflage finish was rough and uneven. The result was a further reduction in speed. We discovered clear cases of sabotage during our acceptance checks. Cables or wires were not secured, were improperly attached, stretched or even been visibly cut.

[Kurfürst]

Yeah, I agree Milo, Mike's site is a bit selective of the facts and hardly anybody takes it seriously given the amount of bias in it.
The things you mentioned are typical examples : he's familiar with the clean G-14 performance, but only shows the graph for the gondola equipped ones. etc.

My personal favourite is though the strory he made up about the groundcrew being transferred to the infantry. Now that's really original.
This guy is really desperate, and appearantly hates the 109 more than he loves the Spit, given the sheer amount of material aimed to show the 109 in a bad light, well, with a bit of help from Mike. OTOH, not a single difficulty with the Spitfire is mentioned. It was a flawless design, and the 109 a complete crap, oh yeah, sure. I think the fact that not even the most die-hard Allied fans bother to qoute the site as a source tells it all. The attitude is too bothersome, even for them.

[justin_g]

Some further testing has revealed these facts:

1. AH Bf 109G-6 speeds match the red curve(G-6 Start-Emergency (1/27/58/44)) from the previously linked-to chart.

2. AH Bf 109G-14 also matches this curve at 21000ft and higher(ie: 395mph@1.42ata/2800rpm).

3. AH Bf 109G-14 is SLOWER at its critical altitude of 16400ft(390mph@1.7ata/2800rpm), even though it should have about +300PS more than at 21000ft.

Two things IMO are wrong here:

1. Considering the shape of the performance curve for the G-6/R2(DB 605AM) and extrapolating from the AH G-14's s/l speed of 347mph, the AH G-14 should be capable of least 407mph at 16400ft(Which is still less than the real life data states, but my main point is the relative disparity between speeds at s/l and at critical altitude).

2. With MW50 activated above critical altitude, iirc there was still a small power advantage -> G-14 should be a little faster than G-6 above 21000ft.

[Bruno]

I just ran some quick level speed tests for the G-14:

AH2 BF 109G-14 level speed tests

100% Fuel, FBM  = .001 (minimum; no fuel burn)

1 x 1 MG151/2cm 150 rounds

100ft

WEP - 350 mph
MIL - 320 mph

5000ft

WEP - 369 mph
MIL - 340 mph

10000ft

WEP - 379 mph
MIL - 357 mph

15000ft

WEP -  388 mph
MIL - 366 mph

16400ft (FTH?)

WEP - 390 mph
MIL - 370 mph

20000ft

WEP -  397 mph
MIL - 377 mph

24500ft

WEP - 388 mph
MIL - 378 mph

[Widewing]

Originally posted by Bruno
I just ran some quick level speed tests for the G-14:

AH2 BF 109G-14 level speed tests

100% Fuel, FBM  = .001 (minimum; no fuel burn)

1 x 1 MG151/2cm 150 rounds

100ft

WEP - 350 mph
MIL - 320 mph

5000ft

WEP - 369 mph
MIL - 340 mph

10000ft

WEP - 379 mph
MIL - 357 mph

15000ft

WEP -  388 mph
MIL - 366 mph

16400ft (FTH?)

WEP - 390 mph
MIL - 370 mph

20000ft

WEP -  397 mph
MIL - 377 mph

24500ft

WEP - 388 mph
MIL - 378 mph

Good numbers Bruno.

I just ran some speed tests with 25% fuel (zero burn). The purpose was to find the absolute maximum speed at the plane's best altitude. This is what I got (via E6B).

20,000 ft
ATA 1.48
399 mph

21,000 ft
ATA 1.42
401 mph

22,000 ft
ATA 1.36
399 mph

So, it appears that the 109G-14's best altitude is 21,000 feet. How that compares to actual test data is for our Luftwaffe experts to determine. However, the data is accurate for that specific fuel load.

My regards,

Widewing