Abstract:
Flight tests to determine the dynamic lateral-stability characteristics of the Boulton-Paul IIIA aircraft have been made at aspect ratios 3.8, 3.0 and 2.3. They showed that the changes in damping, period and phase angle were not large when the aspect ratio was varied, but the roll to yaw ratio increased considerably as aspect ratio was reduced. The comparison between the characteristics measured in flight, and those estimated, is generally fair. Agreement is closest over the range of lift coefficient 0.25 to 0.45.
