DB 601: 1' erhöhte Kurzleistung (1,40 ata)

[Kurfürst]

I have always assumed - but could not confirm - it was meant for low altitudes only, probably because the early LW bombers like the He 111P used the DB 601A too and it was a useful extra boost for them when lifting heavy loads.

I was trying to find out a while ago wheter that was a soft limitation ('you really should not - but may - use it for other than takeoff') or a hard one (you really can't use it whatever you do).

The power curves of the DB engines draw the 1-min rating only up to about 1-1.5 km then the line cease. So I wondered, if it can be only engaged in the first supercharger speed..? But there is no evidence to such limitation (yet..?).

Unlike however the 5-min limitation for the Kurzleistung, which was a soft one, the 1' erhöhte Abfluglestung in Db 601 A ( 1.4 Ata) and 601 Aa ( 1.45 Ata) was a hard one: when pushing forward the throttle, a 60-sec clockword was engaged which automatically shut down the erhöhte Abfluglestung after one minute.