Heinkel He.100

[Zipper730]

From what I recall, it used surface evaporative cooling with an extendable belly radiator for low-speed flight: I'm not sure if the figures from a book I was reading was right, but it seemed to have a cruise and dash speed that were close.

 

[tomo pauk]

From what I recall, it used surface evaporative cooling with an extendable belly radiator for low-speed flight: I'm not sure if the figures from a book I was reading was right, but it seemed to have a cruise and dash speed that were close.

What specific model of the He 100 is that about?

 

[Zipper730]

What specific model of the He 100 is that about?

Hang on...

B-Series: He-100 V5
Weights
Empty: 1950 kg
Flight: 2437 kg
Speeds
Maximum: 580 km/h (Bodennähe); 682 km/h @ 5000 m
Cruise: 525-670 km/h
Does bodennähe in context mean at what we'd call "sea level" in the US & UK?
Landing: 150 km/h
Ranges
Optimal: 1200 km
Max speed: 900 km
Gipfelhöhe: Does this mean service or absolute ceiling?
11000m
Engine: DB601M
T/O Power: 1175 PS
Power at 4500m: 1030 PS

C-Series: He-100 V7
Weights
Empty: 1800 kg
Fight: 2580 kg
Speeds
Maximum: 690 km/h
Cruise: 652 km/h
Engine: DB601A @ (1175 PS takeoff power).

 

[tomo pauk]

Does bodennähe in context mean at what we'd call "sea level" in the US & UK?
Gipfelhöhe: Does this mean service or absolute ceiling?

1 - yes, sea level more or less
2 - probably 'service ceiling'

Now about the question from the 1st post.
There is cruise, and then there is cruise. Unfortunately, people at Wikipedia for example, are not persistent in quoting what kind of engine power was used to cruise, nor at what altitude. The only data sheet for the He 100 I have states that, at 5.5km, the He 100 will indeed cruise very fast (665 km/h), and that is when max continuous power is used (= 960 HP at that altitude with ram - that is for the 30min 'high max continuous' power setting). Note that max power is just slightly better and at lower altitude (1020 HP at 5000 m with ram?) thus the max speed will not be much better.
Now, the He 100 can cruise at 560 km/h if the engine is 'throttled back by 40% vs. Kurzlesitung' (5min Kurzelsitung being the max power, aside the 1min take-off power) at 5km - basically, around 600 HP is used for that cruise speed.
Data sheet claims that all max speed test runs were done for altitude between 0 and 5 km, while the climb tests were made up to 6 km altitude; other performance figures are calculated.

 

[GrauGeist]

One of the problems of nailing down specific performance for the He100 types, is that Heinkel's headquarters was destroyed in bombing raids resulting in the loss of records for the various He100 aircraft (and other types, like the He280) that were developed.

 

[tomo pauk]

One of the problems of nailing down specific performance for the He100 types, is that Heinkel's headquarters was destroyed in bombing raids resulting in the loss of records for the various He100 aircraft (and other types, like the He280) that were developed.

For what is worth: Heinkel aircraft data

 

[Denniss]

Dienstgipfelhöhe is Service Ceiling, Gipfelhöhe is absolute Ceiling AKA Max alt

 

[Zipper730]

1 - yes, sea level more or less

Thanks

Now about the question from the 1st post. There is cruise, and then there is cruise.

Kind of like how the P-51B/C could do 395 mph @ 25000 feet, or a more optimal 300 mph at 29800'.

Unfortunately, people at Wikipedia for example

That wasn't from wikipedia: It was from Die Deutsche Luftrüstung: 1933-1945 Band 1/2/3/4 by Heinz J. Nowarra. I was mostly looking into contenders for the Bomber A program. I was interested in the He 100 because of the surface evaporative cooling which they wanted to use on the He.177.

The only data sheet for the He 100 I have states that, at 5.5km, the He 100 will indeed cruise very fast (665 km/h), and that is when max continuous power is used (= 960 HP at that altitude with ram - that is for the 30min 'high max continuous' power setting).

Which is basically the US equivalent of military power?

 

[Shortround6]

Which is basically the US equivalent of military power?

Not quite the same, Both the British and Germans used a 30 minute rating in addition to 5 minute ratings. Germans on occasion had a one minute rating. This was often the rating used for climbs, especially by bombers. There was a lower power level used for "cruise" that was unlimited in length and then a whole range of power settings for more economical cruise. German fuel injection was pretty good at making power without using a huge amount of fuel.

The American "military" rating changed during the war on some engines. At the beginning (or at least 1941/42) it was 5 minutes, some late war (but not all) got 15 minute time limits on Military power.

However the US NEVER had a 30 minute rating, it was either 1 hour or max continuous (run out of fuel). So US engines are either going to have a bit higher rating than the German max continuous rating but was supposed to be used for a short period of time or they had a bit lower rating that had no time limit (temperature and fuel availability permitting).
They also had a range of lower power settings for economical cruise.

WEP or WER was NOT military power. Military power could be used repeatedly in flight, subject to cooling off periods with no notifications to the crew chief or notations in the log book/s. the use of WEP/WER required both and also required extra maintenance procedures.