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Old 08-09-2012, 07:44 PM
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Chromius Chromius is offline
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Location: Manchester, New Hampshire
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Default Ju-88 a1 Jumo 211B BETA 1.08.18956

The poor Ju-88 needs to brought up to spec. It is roughly 40-50kmh slow maybe more, which is also causing issues with the R-22 not being able to hold altitude

At 2250m (peak pre supercharger performance) with ata 1.25 and rpms 2400 on orange and trimmed for level flight @ 11,000 kg weight. I am only able to get 310 IAS which equates to 353 TAS @2250m. (Yes you can get on the step for a slight increase.)

All data available says the A-4 with Jumo 211J engines was slower than the A-1 with 211B engines due to the A4 having extra armor and load capability along with an addition bulge on the fuselage causing drag and the following charts claim A-4 data.

This performance graph corresponds to a Ju88 A-4, which was test flown without charge air cooler. The first two lines were flown at a gross weight of 13750 kg. The extended kg with a total weight 11500



From http://www.ju88.equitatura.de/performance.htm

And these specs are also based on the A-4

5. Cruise

Enriching lever is in position "Normal".

a) Cruising speeds when mixture control is in position "Lean" ("Arm") and enriching lever in position "Normal":

Altitude V-w Supercharger P2((ATA) n (RPM)
300 350 low gear 1.15 2250
2000 390 low gear 1.15 2250
4000 400 high gear 1.15 2250
6000 400 high gear 1.10 - 1.15 2250

b) Maximum speeds when mixture control is in position "Rich" ("Reich") and enriching lever in position "Normal":

Altitude V-w Supercharger P2((ATA) n (RPM)
300 375 low gear 1.25 2400
2000 410 low gear 1.25 2400
4000 415 high gear 1.25 2400
6000 425 high gear 1.15 - 1.25 2400


In the CEM engine damage model I had the following happen which does not seem right. I was pushing my engines to see what the various limits were when I had a single damaged item, I immediately throttled back and set ata to 1.15 and rpms to 2200 Green/Green.

Engine 2: Water Pump Failure

Had a massive loss of power in engine 2 and much cooler oil temps in eng2
Lost 40-50 kmh in level flight.

Radiator and oil coolers were set the same for 1 and 2, water temps stayed steady.

Throttles were both at 33% for 1.15 ata, rpms and pitch both 2140/73% water 1=84 2=86 identical radiators 30%

Oil temp eng1 84c eng2 32c both coolers at 20%
Oil press eng1 7.4 eng2 8.2

Seems strange that I had some power on 2 but increasing throttle did nothing, yet the ATA matched on both engines set at the same throttle setting? I flew like that with no change to water or oil temps for some minutes.
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Last edited by Chromius; 08-09-2012 at 08:14 PM.
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