Turn Rate

Each aircraft was loaded with 10 minutes worth of fuel and air starts at various altitude were used. The aircraft were allowed to reach 100mph, and were then turned left. The sustained turn rate was recorded.

Each test was run twice. The aircraft were turned for at least two 360 degree turns until the speed stabilised. An average of the next two or three turns was taken. The speed at which the aircraft stabilised was a few miles per hour above stall speed in a turn. That speed:

A) is "right at the edge" with the stall "flutter" sounding.

B) varied with altitude and will vary with fuel loads "in the field".

 Turn Rate LEFT
 Aircraft  1,000ft  2,500ft  3,750ft  5,000ft  8,000ft
 Halberstadt CLII  12.8s  13.5s  14.4s  16.2s  17.3s
 Sopwith F.1 Camel  13.8s  14.5s  15.6s  16.6s  17.7s
 Albatros D.Va  14.4s  15.1s  16.2s  17.4s  18.7s
 Fokker DVII  15.0s  15.5s  15.9s  16.8s  19.2s
 Spad VII  15.7s  16.3s  17.4s  18.6s  20.6s
 R.A.F. SE5a  17.3s  18.0s  18.3s  19.0s  21.3s
 Fokker Dr.1  18.7s  19.5s  20.3s  21.3s  23.6s
 Bristol F.2B  18.9s  19.6s  20.3s  21.6s  23.6s
 Spad XIII  20.3s  21.4s  21.8s  22.6s  25.9s