The US Air Force’s Sikorsky HH-60W Jolly Green II combat rescue helicopter finished its developmental test programme on 13 April.

The service’s new combat search and rescue helicopter wrapped up nearly two years of testing at Eglin AFB in Florida, the USAF said on 15 April.

“The final test by the Sikorsky and air force team was on the aircraft’s weapon systems,” says the service. “The goal of that test was to both demonstrate the performance of the weapons while optimising weapon system configurations.”

The HH-60W first flew in May 2019. The helicopter arrived at Eglin AFB in November 2019 and has been undergoing testing since. The USAF and Sikorsky have accrued more than 1,100 flight hours across six helicopters during the testing programme, says the USAF.

Tests included examination of the helicopter’s flight performance, communications systems, cold and hot weather performance, in-flight refuelling, data links, defensive systems, cabin systems, rescue hoist system and the live-fire of three guns, including its GAU-2 Gatling gun.

The USAF plans to modify testing aircraft for operational use and then transfer the helicopters to rescue units. The Combat Search and Rescue Combined Test force also plans unspecified follow-on testing at Nellis AFB in Nevada in 2022, says the service.

Though the HH-60W has only just completed testing and has not started operations, the USAF and Sikorsky are already planning follow-on upgrades to the helicopter. The USAF granted the manufacturer in February an indefinite delivery/indefinite quantity contract with an estimated ceiling of $981 million that allows for Sikorsky to retrofit the helicopter with new capabilities on a rolling basis over five years.

The need to upgrade the brand-new helicopter is driven by new threats that have emerged since the USAF set down requirements in 2012 and 2013, Sikorsky has said. Those threats are unspecified, but presumably include advanced weapons, such as surface-to-air missile batteries fielded by Russia and China.

The HH-60W is to replace the USAF’s ageing fleet of HH-60G Pave Hawk combat rescue helicopters. Both models are designed to rescue military personnel, in particular downed pilots, in hostile environments, for example behind enemy lines.

The Jolly Green II is based on the US Army’s UH-60M Black Hawk. The advanced variant has additional fuel tanks, giving it an unrefuelled 195nm (361km) combat radius. An in-flight refuelling boom allows the helicopter to fly even farther. The aircraft also has countermeasures to protect against surface-to-air missiles, including digital radar warning receivers, a laser warning system and a missile and hostile-fire warning system.