Paul Lewis/STRATFORD, CONNECTICUT
Sikorsky has adopted a three-step strategy to keep it at the forefront of the world's helicopter industry. Its immediate goal is to sustain output through US domestic UH-60/CH-60 and international S-70 sales, while continuing to press ahead in the long term with the RAH-66 Comanche. It hopes the planned remanufacture of US Navy SH-60R Seahawks and proposed US Army UH-60X Black Hawk upgrade will provide a mid-term bridge.
An indispensable part of Sikorsky's road map is the USN and USN Reserve (USNR) helicopter master plan for the future. The latest refined version calls for the navy to rationalise its 400-strong rotary wing inventory from seven types down to two by 2005. This will be achieved through a combination of remanufacturing, redesigning and retirements.
"We've been very much involved with the planning of the programme," says Sikorsky product development management Jay Verney. "We've worked with the navy so that they could develop a plan that just happened to result in the H-60 helicopter being the aircraft of choice."
The USN's multi-purpose SH-60B, anti-submarine warfare SH-60F and special forces/search-and-rescue HH-60H will be rebuilt to a new common SH-60R standard. The tandem-rotor Boeing CH-46Ds will be replaced by the newly designed and produced CH-60S utility machine, while remaining Bell HH-1N, USNR Kaman SH-2Gs and Sikorsky SH-3Hs will go.
In many respects the USN will not even be operating two different helicopters types but rather one baseline model. The new CH-60S, of which the first of two production examples are scheduled for delivery at year-end, will have much in common with the planned SH-60R. This includes a new digital H-60 Common Cockpit supplied by Lockheed Martin, which promises to reduce support and training costs.
"The biggest saving will be in life cycle costs," says Verney. "Today, each of the navy's helicopters has its own logistical support system, spare parts, maintenance and training. Even within the current H-60 models there are enough variants that a pilot qualified to fly a HH-60H would not be able to fly the SH-60B."
Lockheed Martin has adopted open architecture and commercial off-the-shelf systems for the new H-60 Common Cockpit. This modular approach enables the CH-60S and SH-60R to perform a range of missions that today require seven different types. Roles range from ship-to-ship vertical replenishment and guard duties to more demanding roles of combat search-and-rescue (SAR) and anti-surface warfare.
The baseline cockpit comprises four Litton 200 x 250mm (8 x 10in ) colour liquid crystal displays (LCD), with two for flight information and two for mission data. Other features include dual flight management and mission computers, crew programmable keysets, a new integrated inertial navigation/global positioning system and digital communications suite.
A planned new SH-60R sensor suite reflects the USN's shift from a traditional "blue water" mission to post-Cold War littoral or "brown water" operations. Moving closer to shore and operating in much busier environments brings new challenges in discerning civil air and sea traffic from military threats. Shallower water also presents new acoustic detection difficulties.
The helicopter will have an improved 360¹ -scan multi-mode radar from Telephonics in place of the APG-143. Telephonics has also been selected to supply new communication system for the SH-60R and CH-60S.
Raytheon's AAS-44 forward looking infra-red (FLIR) system will provide an expanded field of view, laser ranging and target designation for the Boeing AGM-114 Hellfire missiles, which is being integrated with the SH-60R and CH-60S. Options include Kongsberg Penguin anti-ship missiles, Mk44/50 torpedoes and cabin mounted M60 machine guns.
Lockheed Martin is developing a new expanded-band electronic support measures system, providing passive detection, location and emitter identification. The integrated system includes four missile warning sensors, two side fuselage-mounted laser detection systems and twin tailboom-mounted automatic chaff and flare dispensers.
Shallow water anti-submarine capability will be improved with the installation of the Raytheon/Thomson-CSF AQS-22 airborne low-frequency sonar now under development. The helicopter will also have an AYK-14 mission processor, UYS-2 acoustic signal processor and provision for eight sonobuoys and launcher. The SH-60B's magnetic anomaly detector will be deleted to make room for a fourth weapons hardpoint.
Individual system testing has begun, with an early SH-60B trials helicopter testing the new FLIR. This testing was due to be concluded by April, after which the new H-60 cockpit will be installed. "We've also developing two production test articles under contract to the US Navy and these will fly next year," says Verney
The first remanufactured helicopter is tentatively set for hand over to Lockheed Martin for system integration in April 2002, with delivery to the USN following that October. Sikorsky plans to modify the helicopters at a rate of between 10-12 a year, with each initially taking 12 months. The company hopes, with time, to cut this to nine months.
This schedule and the final number of machines to be modified is subject to funding and a production contract from the USN. A decision on low rate initial production is due to be made by March next year. Work will start with the SH-60B, of which 170 remain in service, followed by the navy's 77 carrier-borne SH-60Fs and its 42 HH-60s in 2006.
The rebuild process starts with the helicopter's delivery to Sikorsky, which will document the machine's condition before it is disassembled. The current SH-60s were designed for a 10,000h airframe lifetime, and with the oldest now approaching 9,000h, a service life extension is needed. Remanufacturing will extend the helicopter's fatigue life to 20,000h through a combination of structural refurbishment and replacement. The SH-60's tailcone, tailrotor pylon, stabilator, rotor blades and landing gear will be retained and overhauled. These items will then be mated with a new SH-60R cockpit and cabin structures.
USN plans call for the helicopter's twin 1,420kW (1,900shp) General Electric T700-401C turboshafts to be retained and, where necessary, overhauled. There is, however, a possibility that the SH-60R will require an uprated powerplant, since modifying the helicopter will increase its maximum take-off weight from 9,925kg (21,885lb) to 10,700kg.
Any USN decision to re-engine the SH-60R is likely to hinge on the US Army's future plans for its much larger fleet of UH-60 utility machines. There is as yet no formal requirement for a Black Hawk upgrade or new derivative development, but several improvement; studies are under way. These includes re-engining and stretching 250 of the helicopters to a new UH-60X configuration.
The army would like to increase the helicopter's underslung load capability to 5,000kg. The latest standard UH-60L, which is powered by uprated T700-701C engines, is limited to a 4,085kg external load. Aside from a new powerplant and dynamic system, the army is also looking at a 0.9-1.8m (3-6ft) fuselage stretch and installation of a new glass cockpit.
Industry has proposed a range of alternative powerplant solutions, including fitting theUH-60X with the new Sikorsky S-92 GE Helibus' CT7-8 engine, an uprated 1,865kW development of the military T700 series, along with its larger transmission and rotor system. Rolls-Royce Turboméca is promoting the RTM322, which it contends has been demonstrated to 2,310kW and offers more growth potential than the incumbent GE engine.
These engines, however, fall short of the US Army's ambitious goal of an 80% more powerful turboshaft that delivers a 30% reduction in specific fuel consumption and 20% cut in operating costs. Its preference, funding permitting, is the development of a new 2,240kW-class Advanced Common Engine for both the AH-64D and UH-60X. It would draw on elements of the US military's Joint Turbine Advanced Gas Generator demonstrator programme.
The selection of new cockpit avionics comes down to three options. Lockheed Martin is hopeful that the US Navy's selection of its new H-60 common cockpit for the SH-60R/CH-60 will give it the edge with the US Army. The latest UH-60Q medical evacuation/SAR derivative offers a hybrid mixture of Litton multifunction displays and analogue gauges. Sikorsky's integrated common digital cockpit is a third solution.
Source: Flight International
