Pitot Tube, G-2, Air Force US Army WWII 782-02
This is an example of the WWII-era G-2 Pitot Tube used on US Army Air Force heavy bombers B-29 Superfortress, B-17 Flying Fortress, B-24 (J model) Liberator, medium bomber B-26 (F&G models) Marauder,and fighter P-61 Black Widow (according to the US Army Air Force's Maintenance Interchangeability Chart dated Feb 1945).
Pitot Tubes are used to provide impact and static pressures for the operations of various flight instruments. Impact pressure is the resistance encountered by the aircraft moving through the air. Static pressure is the atmospheric pressure of the air at whatever altitude the aircraft may be flying. Static pressure is supplied for the accurate operation of the altimeter and the rate-of-climb indicator. The pressure differential between the impact and the static pressure operates the airspeed indicator.
The G-2 Pitot Tube is mounted in line with the forward direction of travel of the aircraft, such as the side surface of a fuselage or bottom surface of a wing, with the hole pointed in the direction of travel. On a B-17, the G-2 was mounted on a 'mast' affixed to the front fuselage (see photo). The G-2 is heated to prevent icing, powered by a 24 volt DC circuit.
It is in reasonable condition given its age. It is labeled as Property Air Forces US Army, so it is a WWII-era artifact (USArmy Air Force became US Air Force in 1947).