109 performance notes

[gripen]

Originally posted by Kurfürst

And since you started your claims with a lie about the true conditions of the Mtt datenblatt, and you are very selective which tests, regardless of the noted conditions, are to be worshipped, and which are to be neglected and dismissed, which happen to be the ones that disprove your claims, I think we can just safely ignore all what you say. I don't even see a danger of someone actually believing that cr@p, it's that much in-credible.

Hm... the Mtt data sheets are open for everyone to check out what I have claimed in this thread as well as the tests I have quoted.

BTW you have announced to ignore me earlier too.

Originally posted by Crumpp

That sentence says your comparision is not valid.

The prototype G-5/AS values are within less than 3% of claimed speed of the AS.

Originally posted by Crumpp

Changing to a generally more efficient prop does not necessarily mean a level speed increase.

The propeller of the AS ie the 12159 is a high altitude propeller and 10000m is high altitude.

gripen

[Crumpp]

The prototype G-5/AS values are within less than 3% of claimed speed of the AS.

Which has nothing to do with you original contention that a conclusion can be drawn from comparing them with Bf-109G1 performance estimates.

No one is denying that the Bf-109G5/AS data is valid for the prototype Bf-109G5/AS.  You’re like a scratched record.  This is the third time I have had to repeat that.

The propeller of the AS ie the 12159 is a high altitude propeller and 10000m is high altitude.

True, 10,000M is very high and VDW 12159 is supposed to be a high altitude propeller.

Other nice to know information that has nothing to do with your comparision is submarines can dive deep in the ocean and the ocean is very deep.



What does any of this have to do with the your ignorant comparision of the Bf-109G1 performance estimates and flight testing of the Bf-109G5/AS prototype??

All the best,

Crumpp

[gripen]

Originally posted by Crumpp

What does any of this have to do with the your ignorant comparision of the Bf-109G1 performance estimates and flight testing of the Bf-109G5/AS prototype??

It's a fully valid comparison showing that calculated performance of the G-1 is at same class with the flight tested  AS at 10000m. In the flight tests of the production G-1 and mostly similar G-2, the results at 10000m were more than 50km/h below the calculated values ie the difference is far over 3%.

gripen

[Crumpp]

It's a fully valid comparison showing that calculated performance of the G-1 is at same class with the flight tested AS at 10000m. In the flight tests of the production G-1 and mostly similar G-2, the results at 10000m were more than 50km/h below the calculated values ie the difference is far over 3%.

I don't see any Bf-109G1 production machine performance estimates posted in this thread to compare with production Bf-109G1 flight test results.

Nor do I see any Bf-109G5/AS prototype performance estimates to compare with the prototype flight test results.

All I see your conclusions based on an ignorant assumption.

All the best,

Crumpp

[Karnak]

I don't really understand why there is this drive in some people to make their oposition fighter out to be as crappy as possible, cherry picking the data to make it look just so.

Yes, there are examples of poor performing airframes of just about all fighters, but to hold the low end up as the normal performance level seems very biased and suspect.

Cherry picking data to match a preconcieved bias is just poor research methodology.

[gripen]

Originally posted by Crumpp
I don't see any Bf-109G1 production machine performance estimates posted in this thread to compare with production Bf-109G1 flight test results.

Available from NASM as pointed out by Mr. Porta.

Originally posted by Crumpp

Nor do I see any Bf-109G5/AS prototype performance estimates to compare with the prototype flight test results.

The G6/AS (data posted by Mr. elkaskone) is basicly the same as the G5/AS.

gripen

[gripen]

Originally posted by Karnak
I don't really understand why there is this drive in some people to make their oposition fighter out to be as crappy as possible, cherry picking the data to make it look just so.

I don't know if you mean me but lets have a look to the data.

The flight test data for the G-1 is from Mtt test (ie manufacturer) and this data was used as reference in Mtt documentation.

The MT-215 test data (a basicly similar G-2) is from the FAF tests of a new plane in the squadron service and the results are actually somewhat better than Mtt measurements specially at low altitude (mostly due to colder conditions). There is much worse data available if somebody cares to search a bit.

If we compare these measurements to the AH G-2 at 30k (military power):

AH G-2 about 600 km/h
Mtt G-1about 600 km/h
MT-215 about 595 km/h (slightly below spec rpm)

So the flight tests give same kind of performance as the AH G-2, so apparently I'm making the Bf 109G-1 or G-2 to look just as good as it is in the AH. As for comparison the Mtt calculation for the G-1 (Ausführung) gives a bit over 640km/h at same altitude and the calculation for the Endzustand gives something over 670km/h (673km/h at 10000m).
 
Note that these tests are open for anyone to check out: Mtt G-1 data is available from the NASM (as well as Mtt calculations and G-5/AS test data) and MT-215 data is available from the Hallinportti Ilmailumuseo (an aviation museum in Finland) and Sota-arkisto (Finnish war archives). In addition many members of the this BBS have this data allready.

Overall this has quite little to do with the performance of the G-14 with MW-50, I can say that the performance given in the Mtt datasheet is marked as calculation and I have no idea if it is realistic. And the official AH data is not yet avalable so there is not much to discuss about.

gripen

[Kurfürst]

Sure gripen, and all the other flight tests are conviniently ignored by you, pointing a test by Mtt with a DB605 engine that obviously had problems, bringing only marginal (6km/h) speed increase to the 601E 'despite having 200 more HP and a better high altitude propeller', and a Finnish flight test that was done with a draggier version of the 109G-2, ie. photographs of the test MT 215 shows the aircraft had non-retractable tailwheel which unlike most G-1s and G-2s. This was responsible for -20 kph speed loss at alttiude, which curiously would just bring the MT 215 to the level of the other tested aircraft by Rechlin and NII VVS.

[gripen]

Originally posted by Kurfürst
Mtt with a DB605 engine that obviously had problems, bringing only marginal (6km/h) speed increase to the 601E 'despite having 200 more HP.

The output difference between the DB 605A and the DD 601E is between 50-110PS depending on RAM with given ratings. There is no particular problems mentioned in the report. The coolers were more open with the DB605A causing some drag penalty.

Originally posted by Kurfürst

and a better high altitude propeller',

The propellers used for the tests seem to be standard propellers; the 12010 for the DB 601E and the 12087 for the DB 605A. There is no reason to believe that there was large differences in the efficiency.

Originally posted by Kurfürst

 and a Finnish flight test that was done with a draggier version of the 109G-2, ie. photographs of the test MT 215 shows the aircraft had non-retractable tailwheel which unlike most G-1s and G-2s.

Actually most of the Finnish G-2s had a fixed tailwheel when delivered and all G-1s and G-2s got sooner or later fixed tail wheel.

Originally posted by Kurfürst

This was responsible for -20 kph speed loss at alttiude.

According to Raunio and Hörner, the loss was around 10km/h at altitude. And the MT-215 (slightly below spec rpm) did actually roughly 560km/h at 10000m ie about 20km/h less than the Mtt tested G-1.

gripen

[EagleDNY]

Well, according to the Janes I have, the G-14 could have any number DB605 power plants.  Janes lists the DB605 A, AM, AS, ASB, ASM, and D engines as all having been fitted to the G-14, with either MW50 or GM1 power boosting equipment depending upon the exact subtype.

I'll post some of the relavant specs from the engines section below:

DB605 AM: 1,800hp at 2800rpm @ sea level (1.7 ata)
DB605 AM: 1,700hp at 2800rpm @ 13,500 ft (1.7 ata)

DB605 AS: 1,435hp at 2800rpm @ sea level (1.42 ata)
DB605 AS: 1,200hp at 2800rpm @ 26,200 ft (1.42 ata)

I don't know why Janes doesn't have them tested at the same boost pressure, but that's the specs the list for those.

The D engine apparently has 2 subtypes - DB and DC
DB is 8.3:1 compression running 87 Octane and the MW50 system
DC is 8.5:1 compression running 96 Octane and the MW50 system

DB605DB: 1,800hp at 2,800rpm @ sea level (1.8 ata)
DB605DB: 1,530hp at 2,800rpm @ 19,600 ft (1.8 ata)

DB605DC: 2,000hp at 2,800rpm @ sea level (1.98 ata)
DB605DC: 1,800hp at 2,800rpm @ 16,700 ft (1.98 ata)

The DB605DC looks to be the best version of the motor, which tells me that isn't the one that is in the G-14!  The 109K4 is listed in Janes only with the DB605D series motors, so there is some hope that we at least have the best power plant in that.

[Bruno]

Originally posted by EagleDNY
Well, according to the Janes I have, the G-14 could have any number DB605 power plants.  Janes lists the DB605 A, AM, AS, ASB, ASM, and D engines as all having been fitted to the G-14, with either MW50 or GM1 power boosting equipment depending upon the exact subtype.

I'll post some of the relavant specs from the engines section below:

DB605 AM: 1,800hp at 2800rpm @ sea level (1.7 ata)
DB605 AM: 1,700hp at 2800rpm @ 13,500 ft (1.7 ata)

DB605 AS: 1,435hp at 2800rpm @ sea level (1.42 ata)
DB605 AS: 1,200hp at 2800rpm @ 26,200 ft (1.42 ata)

I don't know why Janes doesn't have them tested at the same boost pressure, but that's the specs the list for those.

The D engine apparently has 2 subtypes - DB and DC
DB is 8.3:1 compression running 87 Octane and the MW50 system
DC is 8.5:1 compression running 96 Octane and the MW50 system

DB605DB: 1,800hp at 2,800rpm @ sea level (1.8 ata)
DB605DB: 1,530hp at 2,800rpm @ 19,600 ft (1.8 ata)

DB605DC: 2,000hp at 2,800rpm @ sea level (1.98 ata)
DB605DC: 1,800hp at 2,800rpm @ 16,700 ft (1.98 ata)

The DB605DC looks to be the best version of the motor, which tells me that isn't the one that is in the G-14!  The 109K4 is listed in Janes only with the DB605D series motors, so there is some hope that we at least have the best power plant in that.

The G-14 in AH has the DB605AM. All it is is a G-6 (DB605A) with MW-50 (DB605AM = M = MW-50). All MW-50 does is cool the charge and allow for higher boost by preventing the fuel from detontating.

The other engine the G-14 had was the DB605ASM. The 'AS' indicates that  this DB605A(M) is fitted with the larger supercharger of the DB603. This gave a higher FTH and better performance up high.

The DB605D was fitted on the G-10 and the K-4. It too had the DB603 supercharger and MW-50. The C and B indicate the fuel type. For example a DB605DC ran on C-3 fuel, a DB605B ran on B-4 fuel.

A K-4/G-10 running at 1.98ata rquired C-3 + MW-50 and was only available late in the war (I will let others argue over when and how many) but most G-10 and K-4s did not run at 1.98ata.

In AH the K-4 has a DB605DB. (B-4 + MW-50)

Also GM-1 was never serialized on the late 109s. It provide a performance boost 2000m or so above FTH. With the larger DB603 supercharger 109s high alt performance was sufficient.

[MiloMorai]

German spec sheets on the DB605s

http://mitglied.lycos.de/luftwaffe1/aircraft/lw/DB605_varianten.pdf

[EagleDNY]

Thanks for the note on the fuel codes - I knew they had 87 & 96 octane, I just didn't know their name for it.

I personally would like to see a 109 variant utilizing the DC605DC - maybe we can talk HT into making the K-6 available.  My Janes is showing that as having an additional 2 30mm gondolas (103's not 108's) and IMHO that with the DB605DC powerplant would make a good "slightly perked" 109 variant.  I'm sure it would cause some "brown trousers" in the bombing ranks.

I myself am still testing out the various types - frankly, I'm having plenty of luck perk-farming with the G-2.  It seems like so many folks are used to fighting the rocket-sled 109s they forget that there are a few varieties that can hang in a turn-fight.

EagleDNY    

[Crumpp]

Actually most of the Finnish G-2s had a fixed tailwheel when delivered

There were some other differences too, Gripen in the Finnish 109's.  Can you say "export" version??  No country in the world has ever sold their best equipment to another nation in Tier 1 condition.

All the best,

Crumpp

[Meyer]

K-6 had a new wing with 2 built in Mk-108 (not 103  ), but didn't make it in time before the end of the war