Directory of U.S. Military Rockets and Missiles
Appendix 2: Modern UAVs
Copyright © 2024 Andreas Parsch

Kaman CQ-24 K-MAX

The CQ-24 K-MAX is an optionally manned cargo-lift helicopter, two examples of which are used by the U.S. Marines for test and evaluation purposes.

Kaman developed their model K-1200 K-MAX since the late 1980s, and achieved the first flight in 1991. It was designed and optimized for external cargo load operations. The K-MAX is a single-seat helicopter featuring Kaman's trademark intermeshing twin rotors, which provide for an exceptionally stable platform. The narrow fuselage and the outward-bulging side windows allow the pilot an excellent view on the underslung cargo. With an empty weight of only 2334 kg (5145 lb), the K-MAX can lift loads of up to 2700 kg (6000 lb). The K-MAX was built in relatively small numbers between 1991 and 2003 for civilian customers.

As early as 1998 Kaman began work on a K-MAX version, which could optionally fly without an on-board pilot. In 2007, Kaman partnered with Lockheed Martin to offer this optionally manned variant to military services, and a prototype was first demonstrated in 2008. In December 2010, the Naval Air Systems Command awarded Kaman a contract to supply two unmanned K-MAX helicopters to the Marine Corps for evaluation. In 2014, the DOD assigned the official designation CQ-24A to the unmanned K-MAX.

The CQ-24A can either fly autonomously, using a pre-planned route and GPS navigation, or be controlled by a pilot on the ground. For the latter, the aircraft is equipped with both a line-of-sight datalink and a SATCOM (Satellite Communication) system for over-the-horizon operations.

Photo: Lockheed Martin

In 2011, the two USMC K-MAXs were deployed to Afghanistan. By early 2013, more than 600 missions had been flown, primarily to supply troops at forward outposts to avoid dangerous overland trucking operations. One of the two helicopters crashed in June 2013. The aircraft was eventually repaired, but Marines' K-MAX operations were interrupted for several months. In May 2014, both CQ-24's were returned to the United States. Also in 2014, the CQ-24A played a role in the evaluation of the USMC's AACUS (Autonomous Aerial Cargo/Utility System) technology, which combined algorithms and hardware to allow automatic pin-point landings of unmanned helicopters. The other type involved in that progam was the Boeing H-6U, also known as Unmanned Little Bird (ULB), an unmanned version of the AH-6. In the end, it was announced that the development of AACUS would be continued with the ULB only, and the CQ-24A was therefore retired.

The civilian K-MAX was more successful, and by 2015, Kaman had gained enough new orders to re-open the production line. The main use cases were logging, industrials cargo transportation, and firefighting, and about 60 K-MAX were built between 2017 and 2023. In early 2023, Kaman announced that the production line would close that year. A total of about 100 K-MAX helicopters had been built.

Photo: Pfc George Melendez, USMC

In 2019, Kaman received a contract to bring the Marines' two CQ-24A aircraft back to flight status, to test and evaluate the latest unmanned technology and support future UAV development. The upgraded CQ-24A began flying in mid-2021.


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

Data for CQ-24A:

LengthFuselage: 12.73 m (41 ft 9 in); incl. rotors: 15.85 m (52 ft)
WidthIncl. rotors: 15.67 m (51 ft 5 in)
Height4.14 m (13 ft 7 in)
WeightEmpty: 2334 kg (5145 lb); max take-off, incl. load: 5400 kg (12000 lb)
SpeedClean: 185 km/h (100 kn); with external load: 148 km/h (80 kn)
Ceiling4600 m (15000 ft)
Range560 km (350 miles)
Load Capacity2700 kg (6000 lb) at sea level
PropulsionHoneywell T5317A-1 turboshaft; 1010 kW (1350 shp)

Main Sources

[1] Wikipedia: Kaman K-MAX
[2] Kaman: Kaman Awarded Contract to Reactivate USMC K-MAX® Helicopters
[3] Lockheed Martin: K-MAX® Unmanned Aircraft System
[4] Marines to Reactivate Kaman CQ-24A K-MAX

Back to Directory of U.S. Military Rockets and Missiles, Appendix 2

Last Updated: 13 January 2024