Directory of U.S. Military Rockets and Missiles
Appendix 4: Undesignated Vehicles
Copyright © 2006-2024 Andreas Parsch

4.5 inch HE Rocket M16/M20/M32

Fin-Stabilized 4.5 inch Rockets (M8, M9)

The 4.5 inch Rocket M8 was a fin-stabilized aircraft rocket, the first of this kind developed and used by the Army Air Forces. It was also used as a barrage rocket with ground-based launchers, the 8-tube "Xylophone" and 60-tube "Calliope". But since fin-stabilization is not very effective for low-speed ground-launched rockets, it was replaced later in the war by spin-stabilized rockets of the M16 family (q.v. below). The M9 was a practice round for M8 training.

Spin-Stabilized 4.5 inch Rockets (M16, M17, M20, M21, M24, M32, M33)

The 4.5 inch HE Rocket M16 was the first of the Army's spin-stabilized 4.5 inch rockets. It was fired from 24-tube T66 and M21 "Honeycomb" and 60-tube "Hornet's Nest" launchers. The M16A1 and M16A2 were variants with different fuzing options. The 4.5 inch HE Rocket M20 was a derivative of the M16 for use with the single-rocket expendable M12 launcher. M16 rockets were used by the Army at least until the Korean war.

The 4.5 inch HE Rocket M32 was a significantly improved rocket, with higher speed, greater range, better accuracy and higher lethality than the M16 series rockets.

Image: via ORDATA Website

The 4.5 inch Practice Rockets M17, M17A1, M17A2, M21 and M33 were inert rounds, to simulate the M16, M16A1, M16A2, M20 and M32, respectively. The 4.5 inch Inert Rocket M24 was used in handling and operations training for the M16.


Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Data for 4.5 inch Rockets M8, M16, M20, M32:

Length91 cm (36 in)78.7 cm (31 in)76.7 cm (30.2 in)
Diameter11.4 cm (4.5 in)
Weight17 kg (38 lb)19.3 kg (42.5 lb)18.4 kg (40.5 lb)19 kg (42 lb)
Speed?290 m/s (940 fps)?380 m/s (1250 fps)
Range3660 m (4000 yds)5490 m (6000 yds)8320 m (9100 yds)
PropulsionSolid-propellant rocket
WarheadHigh Explosive

Main Sources

[1] Norman J. Bowman: "The Handbook of Rockets and Guided Missiles", Perastadion Press, 1963
[2] Frederick I. Ordway III, Ronald C. Wakeford: "International Missile and Spacecraft Guide", McGraw-Hill, 1960
[3] ORDATA Online Website
[4] War Department: "Technical Manual TM9-1950, Rockets", July 1945
[5] Department of the Army: "Technical Manual TM9-1950, Rockets", June 1950
[6] Department of the Army: "Technical Manual TM9-1950, Rockets", February 1958

Back to Directory of U.S. Military Rockets and Missiles, Appendix 4

Last Updated: 8 June 2024