A few days ago we recorded some performance data. Air was not entirely
smooth, so speed may be off a few knots.
The cowl flap made a very noticable difference. Also, we got some rain,
and it seems that it cuts a few knots off the speed.
The data below was recorded with the cowl flap in cruise setting (almost
closed) and with dry wings. Airplane (Hi-top Tri gear) was a bit over
MTOW. Power plant is a Rotax 914 coupled to a Woodcomp high twist
2-blade SR3000/W.
I think the fuel consumption is a bit on the high side, what do you
think? (Fuel flow has not been calibrated, sensors were used with
factory calibration, but seems to roughly match with refueling data).
Also, some people later commented that it is better to have a higher RPM
for the Rotax and lower MAP's, any comments on this?
MAP 27, RPM 4500: IAS 121, Fuel flow 15,5 L/h
MAP 29, RPM 4800: IAS 134, Fuel flow 19,7 L/h
MAP 31, RPM 5000: IAS 145, Fuel flow 24,0 L/h
How does this compare?
Any other MAP/RPM combinations I should try?
Frans
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