MauiLvrs
Well Known Member
We based the 20 on the way the plane feels, and what others seem to do.
For normal take-off we use no flaps. The 20 deg. that we use are for short field. 30 deg. felt like it was too much. The gain from 10 deg. didn't seem to be as much as 20 deg. I believe that the number may be between 15-20 deg. as that is what we have experienced. Probably doesn't much matter unless you're flying of a strip 1000' or less. With me and 20 deg flaps on a cool morning, it wouldn't be difficult to clear a 600' obstical at the end of our 4000' runway.
It would be difficult without a wind tunnel to get exact data for the wing/flap configuration. One thing that we have learned is that consistent data is difficult to obtain. Another is that it takes much effort to extract useful data from a dump of the data logger. It samples 1/sec, but extracting say useful CHT data from that is difficult during climb as many of the parameters are changing.
For normal take-off we use no flaps. The 20 deg. that we use are for short field. 30 deg. felt like it was too much. The gain from 10 deg. didn't seem to be as much as 20 deg. I believe that the number may be between 15-20 deg. as that is what we have experienced. Probably doesn't much matter unless you're flying of a strip 1000' or less. With me and 20 deg flaps on a cool morning, it wouldn't be difficult to clear a 600' obstical at the end of our 4000' runway.
It would be difficult without a wind tunnel to get exact data for the wing/flap configuration. One thing that we have learned is that consistent data is difficult to obtain. Another is that it takes much effort to extract useful data from a dump of the data logger. It samples 1/sec, but extracting say useful CHT data from that is difficult during climb as many of the parameters are changing.
Hey Dave,
as a -9a driver with little time on type, I am trying to assemble the correct operational data.
why 20 degrees of flap for takeoff? Have you tested this as the best lift for the wing?