Illustration of the compass swinging procedure for the B-25, from: Erection and Maintenance Instructions for the B-25H-1-NA Medium Bombardment Airplanes, NA-5785, Auguest 1943.

Compass Swinging Rose.
Illustration of the compass swinging procedure for the B-25, from: Erection and Maintenance Instructions for the B-25H-1-NA Medium Bombardment Airplanes, NA-5785, Auguest 1943.
Compass Swinging Rose.