109's kill ratio (all variants from B to K)

[GScholz]

Originally posted by Wilbus
Ohhh long thread... What is it really about now? I haven't read much? Flame fest yet?

109G10/K4 vs. P-51. Not much flaming yet.

[gripen]

Originally posted by GScholz
109G10/K4 vs. P-51. Not much flaming yet.

Hm... I have been under impression that this thread was originally about kill ratio of the BF 109. Somehow this turned to P-51 vs 109G-10/K4 flame fest. BTW under original topic it was much more relevant to talk about how many 109s were really on service than how fast P-51D or 109K-4 was at sea level.

In reality these so called "optimal interceptors" (G-6s, G-14s, G-10s and K-4s) were wiped out from the sky by P-51Ds while these 109s with gondolas and drop tanks were trying to catch high flying bombers (Bf 109 needed wing cannons and also drop tank for that task). The kill ratio was certainly extremely poor in these cases.

gripen

[VO101_Isegrim]

Something of interest I found a while ago :

American pilot Robert C.Curtis remembers :

"My flight chased 12 109s south of Vienna. They climbed and we followed, unable to close on them. At 38,000 feet I fired a long burst at one of them from at least a 1000 yards, and saw some strikes. It rolled over and dived and I followed but soon reached compressibility with severe buffeting of the tail and loss of elevator control. I slowed my plane and regained control, but the 109 got away.
On two other occasions ME 109s got away from me because the P 51d could not stay with them in a high-speed dive. At 525-550 mph the plane would start to porpoise uncontrollably and had to be slowed to regain control. The P 51 was redlined at 505 mph, meaning that this speed should not be exceeded. But when chasing 109s or 190s in a dive from 25-26,000 it often was exceeded, if you wanted to keep up with those enemy planes. The P 51b, and c, could stay with those planes in a dive. The P 51d had a thicker wing and a bubble canopy which changed the airflow and brought on compressibility at lower speeds"

[mold]

Originally posted by gripen
In reality these so called "optimal interceptors" (G-6s, G-14s, G-10s and K-4s) were wiped out from the sky by P-51Ds

I believe this ground has been covered already.  Numerical gangbangs etc.  The K/D doesn't neccessarily tell you which plane is more "optimal".

[VO101_Isegrim]

Originally posted by F4UDOA

 Widewing beat me to it but even the 109K-4 at sea level had 2,000HP and the P-51D had 1750HP and they both had the same top speed. So which aircraft had the higher drag?


It appears most of your similiar statements are suffering from the same problem - wrong data to start with.

For you again:

Bf 109 K-4
DB 605 DC

Power at SL = 2000 PS (1 PS = 0.986 HP) = 1972 HP
Speed at SL = 377 mph

P-51 D with 150 octane, 81 Hg"
V-1650-7

Power at SL = 1940 HP
Speed at SL = 379 mph


Also your comment about the P-51D not being able to disengage at fullpower because it would run out of fuel is rediculous. Just think about that.

WEP time for P-51 D = 5 mins
WEP time for K-4 = 10 mins

Clear case.

Do you even know what the fuel consumption of the 109K4 is? I do I have a entire document on it. The 109 had limited amounts of C-3(Nitrous) and MW-50. It would run out of those additives long before the Mustang would run out of fuel or overheat.

You don`t have anything on that, clearly. So much bs..

ad 1, C-3 is not "nitrous". You don`t even know that... :eek
ad 2, "nitrous" (GM-1 injection) was not used on K-4
ad 3, MW 50 quantity was aduquate for 26 mins of use at full power .
ad 4, If the P-51 would run on 81" Hg for 26 mins, with 197 Impg/gall consumption as the Brit report notes, it would consume (26/60)*197*4.54 = 388 liter fuel, which means the  ~1/3 of the full interal tankage which means you are DRY with your lightweight P-51D at 9000lbs a good time by then. And of course since the V-1650-7 could only run for 5 min at a time then some time has to be spent on cooldown, in fact you have even less fuel left.

etc.

I challenge you to post the documents you claim to have. You won`t do that of course, as you were just bluffing.

Further lies will only make your situation worse.


Also your sustained turn theory doesn't work if the other 109 has a higher stall speed than the P-51D.

Post numbers and source.


If the 109 is pulling max G then he is deccelerating. If the P-51D is not pulling max G the he can still accelerate and fly on the edge indefinetely without loosing E while turning inside the 109.

So the much worser accelerating P-51D can actually beat a K in situation when ability to accelerate is the key...

Acceleration at 250 mph:

K-4 : 6.85 fps
51D : 3.34 fps

You are welcomed to tell me it was the exact opposite, and the Mustang with the ~same drag (as shown above) was able to outaccelate the K-4 with about half the powerloading :

Powerloadings :

K-4 : 1972 HP / 3.362 t = 586 HP / t
51D :
1940 HP / 4.3 t = 450 HP / t [150 oct. at 81" w/o rear tank ]
1630 HP / 4.3 t = 380 HP / t [at 67"]

Notice though, the USAAF`s Mustang run on 71" inches, above data only true to British mustangs.

[VO101_Isegrim]

Originally posted by gofaster
There is a question that's been vexing me for some time.  I'm trying to build scale models of the airplanes used in Aces High, but the only late-war kit of the 109 I can find is the K4.  What is the difference between a K4 and a G10?  I know the K4 had a wooden tail empennage, but is there any other difference in the airframes or armaments?
 

K-4 was different from G-10 in the following :

-rearranged internal equipment (not much interest to you)
-different cocpit arrangement
-no rectangular bulge in the rear of the cocpit (for point above)
-DF loop moved one frame to rear on fusalge top
-long tailwheel*, wheel bay doors for main and tail u/c, rectangular upper fairings for larger wheels on top wing*. Retractable tailwheel
-slightly wider undercarriege
-longer spinner
-circular access hatch for compass deleted on port lower fusalge
-rectangular access hatch on port lower fusalge was redesigned in shape, moved one frame front, and to higher postition
-wooden tail unit* (as a matter of fact, this is true for 90% of the late 109)
-slightly raised upper cowling
-MK 108 being standard. Otherwise same armament.
-abilty to carry bombs as large as 500 kg
-ability to use 115 liter MW tank as ferry tank with fuel
-G-10 being a few dozen kilos lighter, but -20 km/h faster. On the other hand, it climbed marginally better on similiar power.

So much I can think at the moment.

[VO101_Isegrim]

Originally posted by dtango
Hehe Gscholz, the answer regarding acceleration is I don't know !  Seriously though, I don't have enough data to make an accurate assessment.

2ndly you can compare acceleration either as average acceleration or instantaneous acceleration and have different answers.

With the data we have posted in this thread I can make this assessment assuming the data is valid regarding best instantaneous acceleration:

K-4 7400 lbs best climb 4823 fpm
P-51B 9600 lbs with 150 octane 67" Hg best climb 4380 fpm (posted by Neil)

K-4 max sea level speed 377 mph
P-51B 150 octane 67" Hg max sea level speed 379 mph (posted by Neil)

The K-4 probably has the better instantaneous acceleration given the plane configs.  I think this is pretty clear.  The K-4 probably has a better average acceleration vs. the Mustang at 150 octane until toward the upper regions of the speed envelope.  This is reading the tea leaves and I can't say with accuracy this is the case.  Keep in mind that as already been batted around here regarding weights.  As the P-51 burns fuel it would start making up the difference between the K-4's acceleration edge.  How much this would be and if this would ever equalize or "cross-over" I don't know.

Tango, XO
412th FS Braunco Mustangs

I`d only like to congratulate you for your balanced posts, Tango. I can agree fully.

A couple of points though : since the drag coeff of the Mustang is, as told by others,

As for Cd0s : imho calculating them with such a lack of data is pointless. We don`t know exhaust thrust, propellor effiency, radiator thrust.... further we don`t know engine torque (which BTW I belive would favour the larger DB), or the engine/propellor`s ability to "run up" and "accelarate" itself to max. power output...  this Could make the difference in actually available power as much as 20-40% in extreme cases, but at least 15%. It`s already too big margin to tell accurately and compare.

As I already pointed out, Cd0 has little practical relevance, for if you have the exact same drag with a small plane/high WRelated Cd0, and a large plane/low Cd0, then one only make a prestige question of it, but still the fact remains that the two planes with the same power will have similiar acceleration, for the simple matter they have the same DRAG ! Also, since it seems from the speed/power requirement data that the P-51D and 109K had roughly the same drag at max. SL speed, I would believe the K-4 would have less drag at lower speeds, since the Mustang`s laminar flow wings mean the Cd0s are not so Mach-sensitive, whereas the "normal" airfoil on the 109`s is, so at lower speeds the Cd0 it has must be lower as well.

[VO101_Isegrim]

Originally posted by Widewing


Years ago I read an article that discussed the Bf 109's drag issues. It did not employ the Merideth Effect radiator ducting, did not use boundary layer splitters and had all manner of protruding humps, bumps and scoops that contributed to a very high level of parasitic drag.


I don't have a copy of the article, but is was based upon an engineering analysis performed at Langley Field in late 1945, including some wind tunnel runs. It was a Brit magazine, although I can't recall which one.

My regards,

Widewing

I think the article you refer to is Hoerners, however it was shown the basic data he uses is "highly questionable" (=dead wrong), he gives way lower max. speed and an insane (100%) powerplant effiecy.

As regards to the "109 did not use Meredith effect, did not have boundary layer splitters" etc.

Meredith effect was nothing of unusual to be used in WW2 fighter radiators. Even the Spit enjoyed this effect, also Yakovlevs etc, AND the Bf 109. In fact the Bf 109F`s radiators were designed to take maximum advantage of it.

To qoute the relevant part from the Wright Field evaluation of Bf 109 F:

"Each flap is divided in two sections : the outer section is a modified split arrangement serving the additional purpose of controlling the airflow through the internally mounted wing radiators. At the front edge of the radiator is a hinged plate, linked with the trailing edge flaps to open with them. This plate picks up the boundary layer on the underside of the wing, and discharges it on the trailing edge. This form of boundary layer control causes smoother flow  through the radiator, thereby reducing the area for proper cooling".

In other words : the same principle as on the Mustang. Also, oil cooler on 109 worked the same way.

Also of interest :

"The Messerscmitt fusalge is remarkably clear and bulletlike.  The engine is compactly mounted in the nose and enclosed by easily removeable cowling. Proturbulances that mar the clean lines are cut to the minimum by partially submerging the coolant radiators in the wing."

[Neil Stirling1]

Just a quick note to point out that the Mustang that achieved 379mph at SL was fitted with wing racks, it would appear that nearly all P51D's were fitted with them.  Modification stage 1 Item19 (removal) was carried out on Tac R aircraft only. This according to The P51 Merlin Mustang in WW2 by R Freeman.
Can this be confirmed?

Neil.

[VO101_Isegrim]

Good, Neil`s here. Neil, I am making a similiar graph for the Mustang III you just provided. Do you have a similiar for IV which would show above FTH performance as well ? Otherwise I can`t include only but up to ~10 000 ft for IV.

And a slight off-topic : Do you know any wartime indian Spitfire squadrons that employed the Mk 14 during the war ? I asked Mike Williams already, but his listing didn`t include any of those.

[gofaster]

Originally posted by VO101_Isegrim
K-4 was different from G-10 in the following :

-rearranged internal equipment (not much interest to you)
-different cocpit arrangement
-no rectangular bulge in the rear of the cocpit (for point above)
-DF loop moved one frame to rear on fusalge top
-long tailwheel*, wheel bay doors for main and tail u/c, rectangular upper fairings for larger wheels on top wing*. Retractable tailwheel
-slightly wider undercarriege
-longer spinner
-circular access hatch for compass deleted on port lower fusalge
-rectangular access hatch on port lower fusalge was redesigned in shape, moved one frame front, and to higher postition
-wooden tail unit* (as a matter of fact, this is true for 90% of the late 109)
-slightly raised upper cowling
-MK 108 being standard. Otherwise same armament.
-abilty to carry bombs as large as 500 kg
-ability to use 115 liter MW tank as ferry tank with fuel
-G-10 being a few dozen kilos lighter, but -20 km/h faster. On the other hand, it climbed marginally better on similiar power.

So much I can think at the moment.

... and that information will be cut-n-pasted into my other thread for easy reference.  Thank you so much for the details.  I will print it out so I don't lose it!

Thanks again!

[Neil Stirling1]

Adam, the charts that show FS as well as MS for the MkIV/D  are at 67"hg and I think this is where the charts in Americas 100,000 come from. I am visiting the RAF Museum records this week, if I find anything I will let you know.

Spitfire the Story of a famous fighter by Bruce Robertson, this states "later in 1944 a large consignment of MkXIV's arrived at Bombay" However The Spitfire story by A Price gives June 45 and No11 as the date and squadron.

Neil.

[VO101_Isegrim]

Climb and Speed graphs with the Mustang III data Neil provided, plus the other British test with Mustang III I already posted vs. K-4 at 1.8 and 1.98 ata.






Notes :

1, Neil`s Mustang III speed data at 67" shows the plane at takeoff weight corrected to 95%, or approx. 1/3-1/2 fuel load, as usual in British speed tests. IMHO this would give slightly higher speeds above rated altitude, as with the lighter plane, less lift and thus angle of attack would be required to keep the plane level. Reducing angle of attack would of course reduce drag. German practice was to give speeds at full take off weight.

2, On the Climb chart I gave K-4 with 605DC at 1.8ata. It should be known that 605D series engines produced different powers at a great number of possible combinations, including using MW or not, octane rating and type/configuration of engine (DM, DB, or DC) and boost.
This refers to w/o use of MW, giving 1800 PS at SL with 96 octane fuel, a highly unlikely combination, as using DB config at 1.8/1.8 ata would yield 1850 PS w. MW injection, requiring only 87 oct. fuel. I have no chart for that configuration though.
At 1850 PS, I would estimate ~23 m/sec at SL for 1.8ata, with similiar increase up to 6000m.

This was deducted from the climb rates at SL I know with corresponding power :

DC, set to 1.98, running 1.8ata w/o MW : 20 m/sec w. 1725 PS
DC, set and running to 1.8ata w/o MW : 21.7 m/sec w. 1800 PS
DC. 1.98/1.98 w. MW : 24.5 m/sec w. 2000PS.

Indicates roughly 1 m/sec increase per 50 PS.

PS: Neil, I would be very interested in 67" MkIV data, as I don`t trust AHT too much, there are often errors in it. A primary source would be certainly more reliable to use as comparision base on my site.

[VO101_Isegrim]

Originally posted by Neil Stirling1


Spitfire the Story of a famous fighter by Bruce Robertson, this states "later in 1944 a large consignment of MkXIV's arrived at Bombay" However The Spitfire story by A Price gives June 45 and No11 as the date and squadron.

Neil.

Neil, you might find this one interesting. With Sqn number known, it took little time to read a bit on it on the Indian Air Force`s official website :

http://www.indianairforce.nic.in/afhist.htm

"In August 1945, No. 4 Squadron was designated a component unit of the British Commonwealth Occupation forces in Japan, exchanging it`s  Spitfire VIIIs for Mk XIVs in October and arriving in Japan aboard the HMS Vengence in 23rd April 1946."

Hope it`s the same Squad you were talking about. Also checked on the RAF`s site, and appears to be the same.

It seems that the confusion comes from that the VIII and XIVs were very similiar airframes with different engines..

[Grendel]

BTW, going back to the topic:

Me 109s in Finnish service had 25:1 kill ratio 1943-1945.

Originally Me 109s equipped HLeLv 34, an elite squadron built from the best Finnish fighter pilots. In 1944 also HLeLv 24 and HLeLv 30 were equipped with 109s.