Best Piston Engined Fighter Ever...

[Juha]

Hello
I can back up Timppa in that that I saw most of the graphs already some 6 years ago in one excellent Fw 190 Dora site, Haven't check the site in past couple years, so I'm not sure is it still up.

Juha

[lesofprimus]

Good time for our site to become that replacement then....

[Lucky13]

Get cracking people!

[Timppa]

Originally Posted by vanir

A few corrections. As you can see by the second chart you've posted GM-1 cannot be engaged until at least 1km above the critical altitude of the engine in the high supercharger gear, in order to prevent overpressurisation. GM-1 is not used under 11km alt in the Jumo 213E (or 7km in a DB-605A or 6.5km in a DB-601N).

Sondernotleistung is for use of MW50 which is required for manifold pressures exceeding ~1.72atm in the Jumo and you must be under the engine critical altitude. For one kilometre under and one kilometre above the critical altitude the Start und notleistung setting is the maximum manifold pressure the motor can achieve.

Also in terms of altitude speed you can generally use momentum for 0.5-1km above the rated throttle heights for your maximum level speed ratings. In the Ta152H maximum speed heights are invariably 500m above throttle heights for some reason. In other a/c it is usually about 1km but this probably has something to do with the extreme altitudes involved.

So a correctly calculated maximum speed performance chart will show boosted speed at sondernotleistung from sea level to approx.9.5km for the Jumo 213 where the maximum level speed drops to the same as the start u- notleistung setting until 11.5km, when it is again boosted by GM-1 this time (manifold ambient pressure simulates sea level by use of GM-1 and the supercharger ideally kicks back to first gear), dropping again to the start u-notleistung speed rating gradually until 12.5km when the second gear boosts it again, which quickly drops off once again until the final gear kicks in at 13.5km. Take off 0.5km from each of those speed altitude ratings and you get the throttle heights of the Jumo 213E.

In practise however the supercharger of the Jumo 213E was found unreliable at extreme altitude with the use of GM-1 and could give a good speed boost between 11.5-12.5km and wasn't much use over that, plus flying this high was never well advised since the cockpit pressurisation system was also unreliable and nearly killed one test pilot who tried it. Kurt Tank claims he flew the Ta152H to 14km but this is the only record of the a/c flying that high.

Another complication is the unreliability of the third supercharger gear in general, which the Jumo 213E was infamous for. MW50 was not used in the high gear, so it was never used to boost speed above around 5500 metres altitude. Therefore the maximum Sondernotleistung speed height is at around 6km. After that the maximum level speed rating drops to the Start u-notleistung engine setting of ~1.72atm until you reach 11km altitude and kick in the GM-1.

These points are partially displayed in the graphs you've posted above.

These were the reasons the Jumo 213E was found to be quite a disappointment, and did not return its initially calculated performance. According to the latest publication and references it was to be replaced by the DB-603L/LA in the Ta152H some time during 1945 production, about the same time the 190D-14/15 and 152C-1/3 entered major production I assume, and the aliens landed and women started liking us.

As I want to see in the "Flight test data" section only data, not opinions,I answer here:
There were 2 or 3 injection rates for GM-1: 60, 100, or 150 g/sec.(liquid nitrous oxide) according to Hermann, or
100/150 g/s per Jumo 213E performance chart.
Hence the sawtooth speed curve (above 11,500m). If you claim the "sawtooth" was because of different supercharger gear speeds, I would love to see the evidence, because your explanation makes no sense at all.

The DB603 was intended for Ta152C only (and as a backup engine for the rest of the variants).
The Ta152H was intended with Jumo213E-->Jumo212E-1-->Jumo213EB-->Jumo213I
The last one with 2,700hp takeoff power, Nov. 1945.

The H-0 variant was without MW-50 and GM-1 but with the base boost rating increased to 1,900hp.

[IAR80&81]

It is a long list with so many best sky machines. But I believe tracking the performances and operational results during WW II, the best piston engine (propeller) aircraft is Me-109. With all the inconveniences and to be a little outdated at the end of the war, is no match to this great airplane. Small and fastest this was a terrible machine in the hands of skillful pilot. Everybody can check the list of aces from Germany, Finland, Hungary and Romania and that will weight a lot in selecting the great piston airplane.