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Old 06-05-2012, 07:54 AM
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David198502 David198502 is offline
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Quote:
Originally Posted by IvanK View Post
As per the Spit IIA Speed test here is my test on the Hurricane. Wt this time as per the full line on the 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 as per the spec wt as it can be achieved in FMB with the Hurricane

Power setting was Full throttle 3000RPM. Indicated Boost +5.2. 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 +6.25 in the Hurricane

Results plotted as accurately as I could.

thx IvanK for your testing!
and thank you for confirming my observation, that rad settings dont have any effect on speed.
i got flamed a year ago by stating this on this very forum(i tried it with the 109s though)
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