O-1 Ground Loop at NKP
These next two pictures show the classic results
of a ground loop. Aircraft with tail wheels are inherently unstable.
This means that if the aircraft starts to yaw on the ground (yaw is
rotation around the vertical axis), the more the tail starts to swing around,
the more the tail tries to swing farther. In contrast, an aircraft with
tricycle landing gear (nose wheel and the two main gear have the same pattern
as a tricycle) is inherently stable. As the aircraft starts rotating around its vertical axis, the
aerodynamic forces try to push the tail back in line.
Anyway the configuration of the O-1 made the
aircraft more of a challenge to taxi than it was to fly.
On landing, if the tail started to swing around on you, you needed to
push the rudder against the rotation ASAP.
If you didn’t react quickly enough, the rotation accelerated into a
ground loop. The typical result was a violent twist to the fuselage behind the
cockpit, perhaps even breaking off the tail.
The tire at the right of the picture is on the big
portable crane that appears in the picture of NKP in 1966.
