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Old 06-05-2012, 04:54 PM
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Crumpp Crumpp is offline
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Quote:
Originally Posted by IvanK View Post
Attached graphic is my Speed test in CLOD current version + Hot fix.
Blue Line my results, Broken line Spit I spec, full line Spit II spec

METHOD
Each run commenced on altitude with stabilised Oil/Rad temps Oil Temp at 80deg C. Rad Full open (At present I cannot detect any Rad drag so radiator position is not relevant imo)
Each altitude was a specific FMB set up. Altitude maintained +-50ft throughout the test. QNH checked as 992mb on the specific map used.
Each run done 3 times and Vmax average plotted.
Seal level temp estimated 19 deg C based on HEIII OAT gauge on the same map on the ground. TAS calculation based on standard 2 deg C lapse rate from the surface. so at 16,000ft I was using an OAT of -13deg C
My test wt 114lbs less as reported by FMB than the spec wt

Power setting was Full throttle 3000RPM. Indicated Boost +6. Now its important to understand that displayed Boost is not I believe actually measured in the FM but represents an angular animation value. We all know that it should be indicating +9 in the Spit II.

I gave up testing at 17,000ft as things were radically different from the spec values.

Results plotted as accurately as I could.


If someone wants to convert the test values to Standard day figures ... go for it.
It appears a little pessimistic.

Ballparking it off the data you gave I get your Density Altitude at 14000 feet as ~15500 ft.

It looks like the FTH then is ~1000 feet low and the aircraft is about 3% off in SL Vmax.