Original Item: One-of-a-kind. This is a very nice original WWII U.S. Aircraft Night Drift Signal, Mark 4, manufactured by Triumph Explosives, Inc. and dated February 1942. Designed to be dropped from an aircraft over water, the signal would float after impact and produce a bright flame accompanied by white smoke, allowing an aircrew to determine aircraft drift and providing a highly visible reference point on the surface. This early 1942 example retains excellent exterior markings and is in very good to excellent overall condition.

The side retains its original stenciled markings reading AIRCRAFT FLOAT LIGHT M.K. IV / LOT NO. 156 2/42 / TRIUMPH EXPLOSIVES, INC. / R.G. The 2/42 marking indicates production in February 1942, placing this example very early in America's direct participation in WWII.

The AN-Mk 4 was a compact aircraft-deployed pyrotechnic signal with a wooden body, metal nose and tail components, and an internal pyrotechnic candle. When dropped, it descended nose-first and activated upon striking the water. The water-impact mechanism initiated a delay of approximately 8 to 12 seconds, allowing the signal time to return to the surface and orient itself before the pyrotechnic composition ignited. Once functioning, it produced a bright flame approximately 12 to 15 inches high, together with white smoke.

Offered in very good/excellent condition these are exceptionally rare with an example currently on display at the Smithsonian Air and Space museum.

The Triumph Explosives, Inc. manufacturer marking and early LOT NO. 156 2/42 date are especially desirable features on this example. Surviving AN-Mk 4 signals provide an interesting look at the specialized navigation and signaling equipment carried aboard American military aircraft during WWII, equipment that served a far less familiar but important role alongside conventional aircraft armament.

This example is particularly noteworthy for its clearly retained February 1942 date, Triumph Explosives manufacturer marking, lot number, and excellent overall exterior condition. Its specialized function as an aircraft drift and surface-reference signal makes it an unusual surviving piece of early WWII American aviation equipment.

This inert ordnance item has been fully deactivated in accordance with ATF guidelines. It cannot be converted into a functional explosive device and is strictly restricted from international export. 

AN-Mk 4 Specifications
Length: 13 inches
Diameter: 3 inches
Weight: 2 pounds
Burning time: 3 to 3.5 minutes
Time from impact to ignition: 8 to 12 seconds
Release altitude: Under 500 feet
Visibility: Night - 6 to 7 miles

Totally inert, cannot be converted to an explosive device, not available for export. This item is completely legal within the USA. International Military Antiques, Inc observes all Federal, State and Local laws. Everything for sale on ima-usa.com is completely legal to own, trade, transport and sell within the United States of America.

All deactivated ordnance sold by IMA, Inc is engineered to be inoperable according to guidelines provided by the US Bureau of Alcohol, Tobacco, Firearms and Explosives (BATF).