/Vehicles/Allies/USA/08-Halftracks/Data/M21.htm | Up-dated:
81 mm Mortar Motor Carriage M21
GENERAL DATA
Other Designation(s)
-
Type
Mortar Carrier
Radio Equipment
?
Manufacturer(s)
White Motor Co.
Crew
6
Production Quantity
110
Date of first acceptance
January 1944
DIMENSIONS
Combat weight
9100 kg
Height
2.30 m
Length with winch
6.22 m
Ground clearance
0.284 m
Width
2.22 m
Wheelbase
3.442 m
Tread
1.64 m (front) - 1.62 m (rear)
ARMAMENT
Primary Armament
81 mm Mortar M1 (1)
Ammunition Carried
97-112
Traverse
60° to front (Manual)
Elevation
+40° to +85° (Manual)
Traverse speed (360°)
-
Sight
-
Secondary Armament
50cal (12.7 mm) M2HB MG (2)
Ammunition Carried
400
.45 cal submachine gun (3)
600
M1 Rocket Launcher (4)
6
Grenades (5)
12
Mines (6)
12
Location
1: Mount M1 - 2: Flexible on skate mount - 3/4/5: inside - 6: side racks
ARMOR
Assembly
Bolting
Armor Detail
(from the horizontal)
Front
Side
Rear
Top/Bottom
Body
6.4 mm / 66° (Radiator louvres)
13 mm / 65° (Windshield cover)
6.4 mm / 90°
6.4 mm / 90°
6.4 mm / 7° (Hood top) & Open
AUTOMOTIVE
Engine
White 160AX
Type & Displacement
L6
Horsepower (maximum)
147 hp at 3000 rpm
Power/Weight Ratio
16.15hp / ton
Gearbox
Spicer 3461 constant mesh:
4 forward, 1 reverse
Steering
Cam and lever, front wheels only
Brakes
?
Fuel Capacity
227 L Gasoline (Petrol)
SUSPENSION
Type
Semi-elliptic longitudinal leaf spring (Front)
Vertical volute spring (Rear)
Road wheels
Steel ventilated disc (Front)
1 bogie/track; 4 dual/bogie (rear)
Track return rollers
1 dual/track
Sprocket-Wheels
18-tooth front drive
Idler Sprockets
Adjustable fixed at rear of track
Shock absorbers
On front wheels
Track Type
Center guide band type
Width
300 mm
Pitch
100 mm
Links(shoes)
58
Track ground contact
1.187 m
PERFORMANCES
Maximum Speed
72 km/h on road
Range
320 km on road
Mileage
? L/100 km on road
Maximum grade
31° (from horizontal)
Trench crossing
0.76 m
Vertical obstacles
0.30 m
Maximum fording depth
0.81 m
Minimum turning diameter
18 m
Sources
AFV Database
OnWar.com
Vehicles.com
-
Drawings
M21
File
Mortar Motor Carriage