World War II Database

Contributor: C. Peter Chen

ww2dbaseCruiser Mk I Sentinel (AC I) tanks were designed starting in Nov 1940 based on the American M3 Medium design's power train and British Crusader designs' hull and turret in response to the Australian participation in the Desert War in North Africa. The designation "Sentinel" was assigned in Feb 1942 when they entered production, and the first examples emerged from the factories in Aug 1942. They were the first tanks to be built with single-piece cast hulls and single-piece cast turrets. The first 65 Sentinel tanks built before Jun 1943 were equipped with the 40-mm QF 2 pounder guns, and the few built after Jun 1943 carried the larger 57-mm QF 6 pounder guns. Later variant design of Sentinel tanks, AC III and AC IV, carried larger caliber weapons, but these two designs never entered production as the cruiser tank program ended in Jul 1943. The only Sentinel tanks produced in 1943 and earlier were assigned to the Australian 3rd Army Tank Battalion, but none of them ever entered combat; these tanks were later dressed up as German tanks for the purpose of starring in the movie The Rats of Tobruk.

SPECIFICATIONS

AC I

Machinery	Three Cadillac V8 engines rated at 330hp each
Suspension	Horizontal Volute Spring
Armament	1xQF 2 pdr gun (130 rounds), 2x7.7mm Vickers machine guns
Armor	65mm front, 45mm sides and rear, 65mm turret
Crew	5
Length	6.35 m
Width	2.80 m
Height	2.56 m
Weight	27.0 t
Speed	48 km/h
Range	175 km

AC III

Machinery	Three Cadillac V8 engines rated at 330hp each
Suspension	Horizontal Volute Spring
Armament	1x87.6mm QF 25 pdr gun, 1x7.7mm Vickers machine gun
Armor	65mm front, 45mm sides and rear, 65mm turret
Crew	4
Length	6.35 m
Width	2.80 m
Height	2.56 m
Weight	27.0 t
Speed	48 km/h
Range	175 km

AC IV

Machinery	Three Cadillac V8 engines rated at 330hp each
Suspension	Horizontal Volute spring
Armament	1x76.2mm QF 17 pdr gun or 1x87.6mm QF 25 pdr gun, 1x7.7mm Vickers machine gun
Crew	5
Length	6.35 m
Width	2.80 m
Speed	48 km/h
Range	175 km

Photographs