OH-58D Kiowa Warrior Reconnaissance / Attack Helicopter, USA

The Armed OH-58D Kiowa Warrior, in service with the US Army, is supplied by Bell Helicopter Textron of Fort Worth, Texas. Around 375 Kiowas are in service and the single engine, double-bladed armed reconnaissance helicopter has been deployed in support of United States armed forces around the world including Haiti, Somalia and the Gulf of Arabia (Desert Storm and Desert Shield).

In 2002, Kiowas were deployed as part of Nato's SFOR forces in Bosnia and, in 2003, 120 Kiowas were deployed in support of Operation Iraqi Freedom. 29 helicopters were lost during that operation. In August 2007, the US Army Kiowa fleet achieved a total of 300,000 combat hours.

The primary mission of the helicopter is in the scout attack role. The helicopter can be optionally equipped to carry out transport and utility roles using equipment kits installed externally on existing hard points.

A cargo carrying hook is rated to carry loads up to 2,000lb. Emergency casualty evacuation can be carried out transporting two casualties on litters (stretchers), plus over 320kg of supplies to an operating radius of more than 185km. The Kiowa can be used for insertion of up to six troops for critical point security missions.

Two Kiowas can be transported in a C-130 aircraft. For air transportation the vertical tail fin pivots, the main rotor blades and the horizontal stabiliser are folded, and the mast mounted sight, the IFF antenna and the lower wire cutter are removed. The landing gear can kneel to decrease the height.

The OH-58D Kiowa Warrior has been replaced by the next-generation armed reconnaissance helicopter (ARH) within the US Army. The contract for the ARH, a military version of the Bell 407, was awarded to Bell Helicopter in July 2005. 368 helicopters are to be delivered between 2008 and 2013.

To maintain the safety and effectiveness of the Kiowa fleet until retirement, a safety enhancement program is underway, which includes engine upgrades and improved computer control systems. The programme is due to complete in 2010.

Two Bell 407 helicopters were delivered to Rotorcraft Leasing, one of the largest helicopter operators in the Gulf of Mexico, in February 2009. Rotorcraft's Bell 407 fleet increased to 12 with the addition of two 407 helicopters and its total Bell fleet is increased to 149 helicopters.

In March 2009, the US Army awarded a contract to Bell Helicopter to upgrade an additional 27 OH-58D aircraft under the Kiowa Warrior safety enhancement programme (SEP). The SEP includes engine upgrades and improved computer control systems. The programme is due to complete in 2010.

Upgrade work on the 27 aircraft began in April 2009 and deliveries started in the last quarter of 2009 at a rate of three aircraft a month. The upgrade is being carried out at the Bell Helicopter's Plant 1 facility in Fort Worth, Texas.

OH-58D cockpit

The Kiowa was the first US Army helicopter to have an all-glass cockpit. The cockpit is supplied by Sperry Flight Systems and is equipped with a multiple target tracking / moving target indicator, an ANVIS (aviation night-vision system) display symbology system and helmet-mounted display.

The primary multi-function displays provide situation information, communications control and the mast-mounted sight video. A video recorder stores television and thermal imagery from the mission and allows playback in the cockpit.

Kiowa weapons

The OH-58D is equipped with two universal quick-change weapons pylons. Each pylon can be armed with two Hellfire missiles, seven Hydra 70 rockets, two air-to-air Stinger missiles or one .50-calibre fixed forward machine gun.

Mission processors control the suite of mission subsystems via a military standard 1553B bus. An onboard computer provides laser ranging and target location within 10m.

Countermeasures

The countermeasures suite includes an AN/ALQ-144 infrared jammer, radar warning receivers against pulsed and continuous wave radars and a laser warning detector.

Fire control and observation

The distinctive mast-mounted sight (MMS) from Boeing, situated above the rotor blades, enables the Kiowa Warrior to operate by day and night and to engage the enemy at the maximum range of the weapon systems and with the minimum exposure of the helicopter.

The MMS contains a suite of sensors which includes: a high-resolution television camera for long-range target detection; a thermal imaging sensor for navigation, target acquisition and designation; a laser rangefinder / designator for target location and guidance of the Hellfire missiles and designation for Copperhead artillery rounds; and a boresight assembly which provides in-flight sensor alignment. The laser rangefinder / designator is also employed for handoff to an AH-1 Cobra helicopter for TOW missile engagements.

The MMS is principally used for collecting imagery and target acquisition data of the battlefield during the day or night, under extreme adverse conditions.

DRS Technologies is currently responsible for the sensor suite and, in March 2004, was awarded an $8.2m contract to upgrade the thermal imaging system on the MMS. The thermal imaging system upgrade (TISU) provides enhanced target detection and range. Deliveries began in August 2005 and were completed in early 2006.

The contract is part of a five-year $514m master indefinite delivery / indefinite quantity (IDIQ) contract awarded to DRS in December 2003.

In February 2006, the US Army Aviation and Missile Command (AMCOM) awarded another TISU contract worth $33m. Product deliveries began in February 2006 and were completed in December 2008.

A new five-year contract (January 2009-December 2013) worth $913m was awarded to DRS in February 2009 to support the maintenance, repair and service of the MMS on the OH-58D Kiowa Warrior. This is a follow on of the previous $514m contract.

Under the contract, DRS was awarded a $110m contract to supply spare components, repairs and programme services for the MMS in April 2009. The contract includes delivery of new spare parts from June 2009 to March 2013 with repair and maintenance services scheduled from June 2009 to January 2012.

Navigation and communications

The US Army OH-58D is equipped with an attitude heading reference system (AHRS) from Litton and an integrated Global Positioning System and Inertial Navigation System, GPS/INS.

A data-loading module allows the pre-mission storing of navigation waypoint data and radio frequencies. The mission equipment includes an improved data modem for digital battlefield communications, (IDMDBC). The communications system is based on the Have-Quick UHF and SINCGARS FM anti-jam radio.

Kiowa Warrior engine

The OH-58D helicopter is equipped with a Model 250 485kW turbine engine from Rolls-Royce. The transmission has a transient power level of 475kW. The engine and transmission system have been upgraded to provide high performance levels in high temperature and extreme climates.