Erhöhte Notleistung
 

Hi guys

I have been researching some into the specifications for the BMW 801 D-2 engine and the effects that erhöhte Notleistung had on the preformance of the Fw 190 A-8. Unfortunately there seem to be a number of conflicting figures given for the power output that this system had on the fighter. I have seen that the BMW 801 D-2 was rated at 1,700 PS for take-off and emergency and 1,500 PS for climb and combat. Are these figures correct? Regarding erhöhte Notleistung, I have seen that this boosted power output to 1,980 PS while other sources give a figure of 2,000 PS. Could some one please inform me which is the correct figure? Many thanks.

Horrido!

Leo

Edit: I have read new information by Crumpp from www.white1foundation.org in which it appears that the BMW 801 D-2 was improved in the summer of 1943 with a revised exhaust system and new fuel pump among other changes that increased output to 1,800 PS at take-off and emergency and 1,560 PS at climb and combat. This was the engine fitted to the Fw 190 A-8 and when erhöhte Notleistung was fitted it boosted output to 2,050 PS.

Re: Erhöhte Notleistung
 

Dear Leo Etgen,

I have written about the increased power of the BMW 801 D-2 engine "Erhöhte Notleistung" a short description. You can read it here:

http://www.cockpitinstrumente.de/arc.../Dokumente.htm

Please go to M -Motoren- and then to "BMW 801-D Leistungssteigerung"

Best wishes
Dietmar Hermann

Erhöhte Notleistung
 

Hello Hermann

It was interesting to read that C3-Einspritzung may have been used in the Fw 190 A-8 as I was always under the impression that this system was used only in Jabos. It is unfortunate that there is no way of knowing how many fighters may have had this system installed but I have read that it was of limited use to fighters as power production decreased rapidly above 1,000 meters. Just one question: in your research did you come across any information that would suggest that Erhöhte Notleistung may have been fitted to individual fighters before it was serialized in July 1944? I have always had this doubt as the installation appears to have been quite a simple affair. Many thanks.

Horrido!

Leo

Re: Erhöhte Notleistung
 

The term "Erhöhte Notleistung" was used earlier for the 1,42 ata/2700 rpm rating while the original "Notleistung" rating was 1,35 ata/2450 rpm. That was the situation July 1942, see the last page of the document here:

http://www.wwiiaircraftperformance.o...t-30july42.pdf

Hermann probably has more information when the earlier rising of the "Noteistung" (from 1,35ata/2450rpm to 1,42ata/2700rpm) happened.

Erhöhte Notleistung
 

Hello Pihl

Many thanks for the link to the document. However, I am somewhat confused as I did not see any reference to Erhöhte Notleistung but rather to erhöhten Startleistung (2,700 U/min. @ 1.42 ata) and erhöhten Steigleistung (2,400 U/min. @ 1.32 ata). If I am correct these are the settings when the boost limitations of the BMW 801 D-2 were released and the engine was cleared to run at full power. The earlier de-rated settings were Start- und Notleistung (2,450 U/min. @ 1.35 ata), Steig- und Kampfleistung (2,350 U/min. @ 1.28 ata) and Dauerleistung (2,250 U/min. @ 1.14 ata). This appears to have occurred by 12 October 1942 for what I have read. If I am understanding correctly, by mid-1943 the improved BMW 801 D-2Q with revised exhaust among other changes thus increasing output to 1,800 PS was being installed on the Fw 190 A-6. Erhöhte Notleistung which was serialized in July 1944 on the Fw 190 A-8 added another 250 PS but was rather rough on the engines. It is possible that this system was available previously as a field modification but I am not certain and would like to know if this was indeed the case. In December 1944 Alkohol-Einspritzung began to be installed in some aircraft due to the shortage of C3 fuel. This was the system used on the Fw 190 D-9 as well. Any comments or corrections to the above would be greatly appreciated as I am far from being knowledgeable about this area of research.

Horrido!

Leo

Re: Erhöhte Notleistung
 

Hello Leo,
You are right that it does not directly refer to the rising of emergency power (Notleistung), however I think that it's clear that rising of the take off power (Startleistung) means rising of the emergency power as well because they earlier use the term "Start- u. Notleistung".

Regarding the 1,42ata/2700rpm setting, I have not seen concrete evidence when it was released for the service use. I have a Rechlin paper from January 27 1943 which still refers climb power as 1,28ata/2350rpm and full power rpm as 2450.

Anyway, my main point here is that the term "Erhöhte Notleistung" was probably used in many occasions and with many different engines when the higher ratings were introduced to the service.

Harri