Jump to:
M1917
M1917A1

Six-ton Tank M19171-9

M1917: General
Date of first acceptance October 1918 Total acceptances 950
Manufacturers
  • Van Dorn Iron Works
  • Maxwell Motor Co.
  • C.L. Best Co.
Crew
2 men:
  • Gunner in turret
  • Driver in hull center front
M1917: Dimensions
Combat weight 14,500lbs
6,580kg
Height 91"
230cm
Length with tailpiece 197"
500cm
Gun overhang forward 0"
Width over tracks 70"
180cm
Tread 57"
145cm
Ground clearance 16.2"
41.1cm
Fire height 70"
180cm
Turret ring diameter 36"
91cm
Ground pressure, zero penetration 6.9psi
.48kg/cm²
M1917: Armament
Type Mount Ammunition Traverse Elevation
37mm Gun M1916
--OR--
.30cal M1919 MG
Ball mount in turret 238 rounds 37mm
(25 ready)
--OR--
4,200 rounds .30cal
360°;
30° in mount
(manual)
56° in 37mm mount
(manual)
38° in .30cal mount
(manual)
Aiming equipment
Telescopic sight M1918 (tank) for gunner
M1917: Armor
Assembly
Bolting and riveting
Hull
Rolled face-hardened steel
Location Thickness Angle from vertical
Driver's cupola .60"
1.5cm
17°
Driver's doors .31"
.79cm
70°
Front .60"
1.5cm
30°
Sides .60"
1.5cm
Rear .60"
1.5cm
Front top .31"
.79cm
90°
Rear top .31"
.79cm
65° to 90°
Floor .25"
.64cm
90°
Turret
Rolled face-hardened steel
Location Thickness Angle from vertical
Gun shield .60"
1.5cm
Front .60"
1.5cm
12°
Sides .60"
1.5cm
12°
Rear .60"
1.5cm
12°
Top .31"
.79cm
73° to 90°
M1917: Automotive
Engine Buda HU modified; 4 cylinder, 4 cycle, vertical L-head gasoline
Horsepower Gross: 42@1,460rpm Fuel capacity 30gal
113L
Transmission Selective sliding gear, 4 speeds forward, 1 reverse
Steering Clutch-brake, steering levers
Brakes Mechanical, external contracting
M1917: Suspension
Type Road wheels Track return rollers
Coil and leaf spring 2 bogies/track;
5 track rollers/front bogie, 4 track rollers/rear bogie
6/track
Drive sprockets Idlers Shock absorbers
15-tooth rear drive Adjustable at front of track None
M1917: Track
Single pin, cast steel with integral grouser
Width 13.375"
33.973cm
Pitch 9.842"
25.00cm
Shoes/track 32 Ground contact length 79"
200cm
M1917: Performance
Max level road speed 5.5mph
8.9kph
Max trench 84"
210cm
Max grade 70% Max vertical obstacle 36"
91cm
Min turning diameter with tailpiece 20'
6.1m
Max fording depth 24"
61cm
Cruising range ~30mi, roads
~48km, roads

The six-ton tank M1917 was originally known as the six-ton special tractor model 1917, and was the American version of the French Renault FT. The measurements for the tank were switched from metric to English for the American conversion. Some other differences present in the Americanized model were replacement of the steel-rimmed wooden idler wheels with all steel wheels, American weapons, a different engine that featured the exhaust muffler on the left side of the hull, and a bulkhead separating the crew from the engine. The idler adjustment mechanism was changed to utilize a screw on each side instead of the single fork used on the French machine. Hooks were used as tow points, and an extra outward-facing hook was added to each side of the upper hull just behind the turret to aid in shipping. The American tanks also had an additional plate featuring a vision slot on either side of the driver necessitated by allowances from the change in measurement systems. The top of the tailpiece was secured by a threaded rod with handles screwed onto each end. All M1917s were fitted with a riveted octagonal turret, as opposed to some French tanks which were fitted with a round cast turret. The machine gun M1917s were originally armed with the .30cal Marlin tank machine gun, but this was switched to the Browning M1919 starting in 1919. Browning tank machine gun tanks had a vertical seven-compartment ammunition belt rack hooked to a bracket on each side of the gunner's compartment. Each compartment could hold six 50-round ammunition belts on a hinged hook. 37mm ammunition was stowed in a 100-round rack on each side of the gunner's compartment, each having four horizontal rows that could accommodate 25 rounds; a 13-round rack suspended from the bottom of the front of the left 100-round rack, though it could be moved to the opposite 100-round rack; and a 25-round rack attached to the right side of the turret.

Of the 950 M1917s, there were 374 37mm gun tanks, 526 machine gun tanks, and 50 signal tanks which possessed no armament but carried a radio in a fixed superstructure.

Top

                                                                                                                                                                                                                                                                                                                                                                                                                                                                       



Six-ton Tank M1917A11-3,10-11

M1917A1: General
Date of introduction 1930 Total acceptances 7 converted from M1917
Manufacturers
  • Holabird Quartermaster Depot
  • Ordnance Department shops
Crew
2 men:
  • Gunner in turret
  • Driver in hull center front
M1917A1: Dimensions
Empty weight 14,200lbs
6,440kg
Height 91"
230cm
Length with tailpiece 208"
528cm
Gun overhang forward 0"
Width over tracks 70"
180cm
Tread 57"
145cm
Ground clearance 16.2"
41.1cm
Fire height 70"
180cm
Turret ring diameter 36"
91cm
Ground pressure, zero penetration, empty 6.7psi
.47kg/cm²
M1917A1: Armament
Type Mount Ammunition Traverse Elevation
37mm Gun M1916
--OR--
.30cal M1919 MG
Ball mount in turret 238 rounds 37mm
--OR--
4,200 rounds .30cal
360°;
30° in mount
(manual)
56° in 37mm mount
(manual)
38° in .30cal mount
(manual)
Aiming equipment
Telescopic sight M1918 (tank) for gunner
M1917A1: Armor
Assembly
Bolting and riveting
Hull
Rolled face-hardened steel
Location Thickness Angle from vertical
Driver's cupola .60"
1.5cm
17°
Driver's doors .31"
.79cm
70°
Front .60"
1.5cm
30°
Sides .60"
1.5cm
Rear .60"
1.5cm
Front top .31"
.79cm
90°
Rear top .31"
.79cm
65° to 90°
Floor .25"
.64cm
90°
Turret
Rolled face-hardened steel
Location Thickness Angle from vertical
Gun shield .60"
1.5cm
Front .60"
1.5cm
12°
Sides .60"
1.5cm
12°
Rear .60"
1.5cm
12°
Top .31"
.79cm
73° to 90°
M1917A1: Automotive
Engine Franklin series 145; 6 cylinder, air-cooled, gasoline
Horsepower Gross: 100@3,100rpm Fuel capacity 30gal
113L
Transmission Selective sliding gear, 4 speeds forward, 1 reverse
Steering Clutch-brake, steering levers
Brakes Mechanical, external contracting
M1917A1: Suspension
Type Road wheels Track return rollers
Coil and leaf spring 2 bogies/track;
5 track rollers/front bogie, 4 track rollers/rear bogie
6/track
Drive sprockets Idlers Shock absorbers
15-tooth rear drive Adjustable at front of track None
M1917A1: Track
Single pin, cast steel with integral grouser
Width 13.375"
33.973cm
Pitch 9.842"
25.00cm
Shoes/track 32 Ground contact length 79"
200cm
M1917A1: Performance
Max level road speed ~9mph
~14.5kph
Max trench 84"
210cm
Max grade 70% Max vertical obstacle 36"
91cm
Min turning diameter with tailpiece 20'
6.1m
Max fording depth 24"
61cm
Cruising range ~30mi, roads
~48km, roads

The rear hull of the M1917A1 was longer and taller to accommodate the new engine. The tanks were also equipped with a self starter, and the engine, transmission, and clutches were mounted as a single unit, which eased maintenance. The increased weight and speed necessitated strengthening the idler wheel rims. The engine was governed down to 2500rpm to prevent damage to the powertrain components.

Top



References

  1. Hunnicutt, R.P. Stuart: A History of the American Light Tank, volume 1. Navato, CA: Presidio Press, 1992. Reprinted with permission from Stuart, R.P. Hunnicutt ©1992, available from Presidio Press, 505B San Martin Drive, Suite 160, Navato, CA 94945.
  2. Lemons, Charles. The Six Ton Special Tractor Model 1917. lulu.com, 2017.
  3. AGF Board No. 2. Development of Armored Vehicles, volume 1: Tanks. 1947.
  4. TR 1325-A Tanks: Six-ton Tank, M1917. Washington, DC: War Department, 2 January 1934.
  5. TR 1320-39 C1 Weapons: Browning Tank Machine Gun, Caliber .30, Model of 1919. Washington, DC: War Department, 1 May 1926.
  6. Tank Data, vol. 2. Aberdeen Proving Ground, MD: US Army Ordnance School, July 1958.
  7. Clark, 2LT Chad G. "Radio to Free Europe: Armored Force Radio Development, Great Britain and the United States 1919-1941." Master's thesis, University of Nebraska, 1998.
  8. Handbook of Ordnance Data. Washington, DC: Office of the Chief of Ordnance, 15 November 1918.
  9. Sola, Samuel, Vincent Bobkowski, and Kara Crocker. Weapon Mounts for Secondary Armament. Santa Monica, CA: G. O. Noville & Associates, Inc., April 1957.
  10. Hogg, Ian V. The Greenhill Armoured Fighting Vehicles Data Book. London: Greenhill Books, 2000.
  11. Kirk, William. "Light Tanks." TANKS! 21 June 2000. 5 December 2000 <http://mailer.fsu.edu/~akirk/tanks/UnitedStates/lighttanks/​LightTanks.html>. TANKS!
Last updated 24 Nov 2023.
Questions? Comments? Corrections? Email me
© Copyright 2000-23 Chris Conners