Terminology and engine data

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Thank-You Tomo!

I did not dare think it was Feb '45! The DB 605 DB and DC Motorenkarte is Dez '44.
For the late DB603, this is very good information. I suspect that the 603 E/EB/EC were possibly destined for the He 219 or maybe Do 335 versions. I think these very late types just show how the plans for other high output piston engines had collapsed.
I think this Motorenkarte is important because it shows information for Troops to use with actual production engines, or at least engines that were actually being built. IMO, this is better information than many other sources.
Thanks again for posting that! Excellent!

Eng
 
1 ata is worth about 14.5 psi.
+25 psi = 2.8 ata then?
Thanks for that, there are some very useful figures on Merlin and V-1650 wiki articles , but not quite all pressures are given as ata as well. For +25 psi it was given as 2.7 ata. For my own education 1.8 ata would be around (but under) +12 psi and 2 ata around +15 psi, while a typical 1.42 ata would be about +6 psi.
It was also derated wrt. the max allowed RPM, for all the power settings. restrictions ended by October of 1942, when BMW finally debugged it.
Max rpm allowed was 2450, boost indeed 1.35 ata. We know for a fact the power made at 2400 rpm and 1.32 ata, ie. 1520 PS at 700m (low gear), and 1320 at 5300m (see this post). Another data point is 2700 rpm and 1.42 ata, making 1730 PS and 1440 PS at 600m and 5700m, respectively.

We can expect, for a derated 801D, a bit above 1550 (certainly under 1600 PS) down low, and ~1350 PS at ~5400m? Basically, similar to the fully rated 801C down low, and a bit better than the 801C at higher altitudes. Note that I'm not aware of 801C power figures for 2700 rpm in 2nd gear - official data I have allows only for 2550 rpm in 2nd gear.

See here for 2700 rpm 801C in 2nd gear flying in late 1941.
Again much appreciate this, it's more detail than i hoped for.:)
 
Fw 190 and Ta 152 were also mooted with these engines, even including re-engining the surviving BMW-powered airframes.
OK. Some Ta 152 C built with DB 603 L versions with 2-stage superchargers.

Eng
 
OK. Some Ta 152 C built with DB 603 L versions with 2-stage superchargers.

Eng
This is what I was referring to:

umbau.jpg
 
Oh wow, that's a fantastic topic. Well if it isn't much, i am still coming to grips with converting ata to psi to inch Hg, i have found a very useful table but it only goes to about 1,80 ata/+11 psi. Is there something going to +25 psi by any chance?

Also, very curious, what's the PS rating for the BMW-801D-2 derated to 1.35 ata?

See a conversion spreadsheet (Excel) in post #72.
 
This is what the power vs. altitude values were supposed to be for the Jumo 222 and DB 603A, as promised by the respective engines' manufacturers in 1940 (note the rather big propellers envisioned, 4.30 m diameter for the case of Jumo 222):

191.jpg

Power vs. altitude graph for the Jumo 213A-1 as it should've been in mid-1943:

jumo 213A.jpg

Later graph for the 213A: link

Graphs that go with the above tables:

2power22.jpg 6power03.jpg
 
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Three well-known DB engines; effects of the different values of ram pressure are shown for the 'Steig & Kampfleistung' of the DB 601E:

DBs.jpg

...and a lesser-known BMW:

139.jpg

(per manufacturer's data; as it can be seen by the hand-drawn 'ornaments', things were changing a lot :) )
 
Three well-known DB engines; effects of the different values of ram pressure are shown for the 'Steig & Kampfleistung' of the DB 601E:

View attachment 701990

...and a lesser-known BMW:

View attachment 701991

(per manufacturer's data; as it can be seen by the hand-drawn 'ornaments', things were changing a lot :) )
Hi Tomo,
Which document is the DB 601E, 605 and 610 photo taken from please? I see it is just pages 2 and 3, so I presume it is a short briefing doc? Can you please post it all, sometimes there are little clues in the details.
Thanks,
Eng
 
From the Lufthansa's manual:

Thank you Tomo, your downloads are very good!
So, this is an interesting Lehrgange or "teaching program" about the DB 601E, 605 and 610 for Lufthansa employees.
It combines elements from the DB Handbuch and the DB repair guide, with some illustrations. It is an interesting document. However, although there is some detail in various sections, the technical detail is not deep and I would not like to attempt any mechanical work on the engines from this document alone.
Thanks for posting!

Eng
 
For what it's worth, some IAR K14 IV C32 engine details (which in many sources is called the same plus 1000A or IAR K14 1000A or A1 or A2 with A2 variant being for IAR-39 and IAR-47, or simply IAR-1000A1/A2, things are very confusing) from the IAR-80 manual 1943. The manual can be found here, along with the 1941 edition, spare parts catalogue as well as various other details through the site.

It seems you can't download the manuals so i took these two screenshots below from different pages in the manual. Strangely, the engine weights are different, 705 kg and 720 kg. And in the 1941 edition the weight is quoted as 688 kg.

So it seems the basic numbers for the engine are 960 HP at 2300 rpm and 935 mm Hg for take-off, and 1000 HP at 3200 m (4500 with ram) with 850 mm Hg and 2300 rpm. The 1941 manual says the ram altitude is 4000 m though.

Although i haven't seen it in the manual, the compression ratio seems to be 5.5:1 according to the IAR-80 book by Radu Branzan (by far the most detailed on it to date)

But things are never simple, on the same site, and also on wiki , there are other power/ rpm data respectively such as 996 HP at 2390 rpm for take-off, and 1100 HP at 2390 rpm at 2600 m. No idea where these figures come from.

And also, there are older figures which i recall reading as a kid, that IAR K14 1000A had 1040 HP at 2500 rpm, and 1140 HP at 2550 rpm for take-off! In fact the other day i found a snippet on the internet that said the compression ratio was 6.14:1 but for the life of me i can't find it now. Separately, on the site above there is mention of a project/prototype for a IAR K14 IV C38 (so a higher rated altitude of 3800 m), and/or a IAR-1000B project, involving among others a higher rpm. So perhaps the 2500 rpm figures are for one of these prototype/projects? At any rate, the manual says the never exceed rpm in a dive is 2450 (but i also saw 2420).

Apparently some people have access to the IAR K14 IV C32 manual (1942 edition), would there be by any chance other romanian members here who have or seen/read this manual?
 

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Not sure if this has been posted before, but i found this file the other day dealing with HS and GR engines, contains some background history, basic details, cutaways etc. I found particularily interesting to see the evolution of the cylinder head from GR 14K, N and R.
 

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Just a quick question, what's the compression ratio of the DB-601E? I THINK it's 7.2 (i've seen couple of mentions of that here and elsewhere) but i'm looking for some original datasheet or other german document to say that. Also, did the 601E have different CR ratios for right and left cylinder banks? Thanks.
 
Thanks for that. Still looking to see a contemporary data sheet for DB-601E if available.
Hi, Well there is the original power ratings table and graph on reply #108 from Tomo Pauk above on this thread. Tomo also posted the whole of that Lufthansa tech manual on post #110, so get that copied! Also, you might find more complete copies of original material if you research online and visit some of the sites. Unfortunately, if you are not good with German language, there are not many translations available.
However, the best material is the original manuals. Copies of most manuals are available from Udo Hafner Archiv.

Eng
 
Data sheet for the Jumo 205D is posted here. Unfortunately, there is no data on the rated height(s).
 

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