Drift Sight, Mk II-B Pelorus, WWII US Navy Aircraft Sally Bomber It is a wonderful reference

It is a wonderful reference document from that era

Here is an engine Torque Pressure Indicator

It is labeled Fl

Indicator ID-92/ARN-6

Drift Sight, Mk II-B Pelorus, WWII US Navy Aircraft Sally Bomber It is a wonderful referenceHere is an early WWII era US Navy aircraft Pelorus Drift Sight. A Pelorus Drift Sight is designed to function either as a Pelorus, for taking bearings on objects, or for improving dead reckoning aircraft navigation by measuring the angle between the heading and the track of an airplane. It consists of a small 'telescope' viewing vertically towards the ground, angled toward the direction of the aircraft. When viewing the ground through the scope while