The US Navy is increasing the pace of flight testing the new Sikorsky CH-60, as it plans to expand a proof-of-concept demonstration of a towed airborne mine counter measures (AMCM) application for the new naval utility helicopter.
Flight-testing of the first CH-60 has been under way at the US Navy's Patuxent River facility in Maryland since mid-May and the helicopter will be joined by three more by next month. The programme has clocked up 20h out of a planned 230h of technical evaluation schedule, due for completion by November.
A three-month operational evaluation will follow, leading to a full-rate production go-ahead decision in March next year. The navy was able to launch straight into tech/eval after only 50h of flight testing at Sikorsky as the result of having already tested the CH-60's new glass cockpit suite using a modified army UH-60 Blackhawk airframe, explains Paul Morgan, CH-60 programme manager.
The prototype YCH-60 has since been employed for the first two phases of the AMCM trials, involving a "tow the Earth" static pull up to 3,859kg (8,500lb) and an actual airborne dynamic tow of a magnetic orange pipe. The helicopter has flown at between 5kt (9.25km/h) and 30kt, pulling loads with a hydrodynamic cable tension of between 2,724kg and 3,632kg.
Concern about the helicopter being forced to fly in an excessive nose-down altitude has proven unfounded, but with one engine inoperative (OEI) there is a need for a greater ceiling margin than the 150-200ft (46-61m) height so far flown.
"Engine out is a function of height. In phase two we're looking at some increase in altitude to make OEI flyable," says Morgan.
A third phase of trials will start in September at Panama City, Florida, during which the helicopter will pull a mock-up of the navy's AQS-20 mine detection sonar. The trial will also be used to demonstrate a prototype carriage and recovery system for the towed sonar mounted in the cabin.
Plans call for the AMCS programme to move to a development programme in 2002 using one of the tech/eval aircraft.
Source: Flight International
