US manufacturer Kaman is offering its Seasprite helicopter for export.


The end of the Cold War has had a severe impact on Western aerospace companies heavily reliant on defence contracts. One US helicopter manufacturer, Kaman Aerospace, has turned the situation to its advantage and begun re-manufacturing surplus US Navy SH-2F Seasprites for sale overseas.

Thirty-six years after the first HU2K-1 prototype was flown, Kaman is hoping to give the helicopter a further lease of life in the form of the re-incarnated SH-2G. For a fraction of the cost of a new naval helicopter, Kaman is offering foreign navies a completely revamped and modernised zero-hour machine.

Kaman has already secured a $150 million order from Egypt, and is attracting strong interest from navies in Asia. The company is also challenging more modern designs, such as the Westland Super Lynx and Eurocopter Panther, for lucrative new naval orders in Australia and New Zealand.


The H-2, as the Seasprite is generically designated in US Navy service, has proved a particularly enduring and flexible design. Despite its apparent age, the helicopter in its latest Super Seasprite guise shares little in common with the original single-engine SH-2A delivered to the US Navy in 1962.

Kaman began work on the H-2 in the late 1950s, to meet a US Navy requirement for a new shipboard utility and search-and-rescue (SAR) helicopter. A total of 186 UH-2A/Bs was eventually delivered to the navy, before the design underwent a series of major changes. In 1966, the UH-2C version was introduced, powered by side-mounted General Electric T58-8B turbo-shafts.

The addition of a second engine provided a much greater safety margin, particularly for H-2 crews performing combat SAR missions over the Gulf of Tonkin, in China, and North Vietnam. A limited number of armored HH-2Cs fitted with GE Miniguns was also produced specifically for use in the Southeast Asian conflict.

During the early 1970s, the H-2 again underwent an extensive conversion programme, this time to meet the US Navy's requirement for a light airborne multi-purpose-system (LAMPS) helicopter to equip its fleet of new FF 1052 Knox-class frigates.

The reconfigured SH-2D LAMPS helicopter formed an integral part of the FF 1052 frigates' weapon systems, providing anti-submarine warfare (ASW) and anti-ship surveillance and missile targeting. The SH-2D was re-equipped with chin-mounted search radar, magnetic-anomaly detector gear, sonobuoy launcher, and two Mk46/50 anti-submarine torpedoes.

New improvements introduced with the SH-2F included a reinforced undercarriage, main rotor and up-rated 1,000kW (1,350shp) T58-8F turbo-shaft engines. After the delivery of the last upgraded H-2 in 1981, Kaman restarted production of new-build SH-2Fs to meet a US Navy order for 60 more helicopters.

The final six machines ordered in 1987, were completed to the much improved, SH-2G standard. The new variant represents the most extensive re-design of the H-2 to date, powered by twin 1,285kW General Electric T700-401 engines and incorporating a new MIL-STD 1555B digital databus.

It had been planned to upgrade 97 H-2s to the new SH-2G configuration. Post-Cold- War defence cuts, however, reduced the programme to just 18 conversions, including one prototype. Reduction of US Navy fleet strength resulted in the pensioning-off of the FF 1052-class frigates and the withdrawal of the SH-2F from service.

"After the fall of the Berlin Wall, there wasn't a lot of effort put into the H-2 programme," says Kaman International programme manager Loring Nichols. "It was felt the US Navy had selected the SH-60 as its next LAMPS aircraft and, without the FF 1052s, there was no longer a need to keep the H-2 around."


The US Navy has retained 16 SH-2Gs to equip early-build FFG 7 Oliver Hazard Perry-class frigates, which have not been refitted to operate the larger Sikorsky SH-60B Seahawk LAMPS Mk3 helicopter. The mix of new and re-manufactured SH-2Gs equips two reserves Naval Air Squadrons, HSL-84 at North Island, California and HSL-94 at Willow Grove, Pennsylvania.

With the transfer of redundant FF 1052s to allied foreign navies, Kaman was quick to recognise new opportunities to keep the SH-2G programme alive. The company has already received an order from the Egyptian Navy for ten upgraded Super Seasprites for use aboard its recently acquired ex-US Navy frigates.

There is a total of 72 SH-2Fs, which is being kept in desert storage, available for rebuild and sale overseas. The fleet varies from high-time machines with as many as 13,000h clocked-up on the airframe, to the latest-build SH-2Fs, which have accumulated as few as 1,000h in the air.

Nichols says: "Because the aircraft were very well kept when flying and then went into the desert, there is very little variance in the work that has to be done on the production line. It's exactly the same, whether it's a 13,000h or 5,000h aircraft."

Each helicopter removed from the desert for remanufacturing at Kaman's Bloomfield plant is examined for any specific corrections, which need to be made. Paint is then stripped down to the primer, or, where corrosion needs to be treated, to the metal.

All electrical and mechanical systems are removed and replaced, including the helicopter's twin T58 engines, forward-drive train, gaskets, seals, fuel system, control cables and rods and interior-sound blankets. The H-2's retractable landing gear is removed and completely rebuilt.

The H-2's rotor system is removed and disassembled for inspection. System components have a life span of 2,500-12,000h and, depending on their condition and remaining service life will be restored for re-use.

Once a fuselage has been completely stripped, it is moved to Kaman's Moosua factory for the fitting of a new, titanium roof structure. The stronger roof is needed to accommodate the SH-2G's two re- placement T700 turbo-shafts, drive system and engine firewalls.

The restored airframe is "...conservatively rated" for an additional 10,000h service life. A fatigue-test programme has indicated that the helicopter has the potential to operate for a further 10,000h beyond that.

Back at Bloomfield, the helicopter is fitted with new engines, three unlimited-life-component gearboxes, a self-lubricating and health-monitoring system, dual-redundant fuel-delivery system, hydraulic plumbing and a gas turbine auxiliary power unit, for self-starting.

The new T700 engines offer a 20% improvement in fuel efficiency over that of the T58, allowing for expanded range and flight endurance. With improved reliability and nearly a 30% increase in power, there is a "significant improvement in the SH-2G's single-engine performance", says Nichols.

Retention of the H-2's original main-rotor transmission, however, has meant that the helicopter's maximum take-off weight remains unchanged at 6,125kg.

In addition to a new dual-redundant 1553B databus, the SH-2G is equipped with a Teledyne AN/ASN-150 tactical navigation system, replacement instrument panels, a new lightweight electrical wiring system, with centrally located circuit breaker panels, and two 30kVA generators.

New mission-avionics fitted to the US Navy's SH-2Gs include an integrated sensor-operator station, a Computing Devices AN/UYS-50 acoustic data processor and 99-channel sonobuoys. "The Canadian UYS-503 is arguably the best processor in the world today, in terms of weight speed and growth architecture," claims Nichols.

Beyond the standard SH-2G upgrade already developed and funded for the US Navy, Kaman has proposed a series of further enhancements to the helicopter's sensors and weapon fit. "If we're to become an international player," says Nichols, "I would expect to see a lot more research and development focused on this."

The company has already begun modifying two SH-2G test aircraft with the AlliedSignal AN/AQS-18 dipping sonar, under contract to the Egyptian navy. The upgrade draws on the experience of Kaman's earlier AQS-10 sonar trials, conducted in the 1960s, using an UH-2A. The single-engine helicopter was found to be under-powered to operate the system effectively.

Kaman has taken advantage of the SH-2G's new, more powerful, engines to develop an automatic hover-coupler system, as part of the 27-month Egyptian programme. Installation of the AQS-18 has also been made easier by a shift in the re-engine helicopter's centre of gravity. "We'll end up with an aircraft purpose-designed for the dipping sonar," claims Nichols.

Egypt is also being tipped as a possible recipient of Kaman's Magic Lantern mine-detection system, as part of a planned second purchase of ten aircraft. Kaman, in the meantime, is pressing the US Navy for a contract to fit the laser system to its remaining reserve SH-2Gs.

A range of other sensors has been fitted to the H-2 in the past, as part of the US Navy's interim Middle East Force upgrade, initiated during the first Gulf War. Tried-and-tested systems include the Hughes AAQ-16 forward-looking infra-red system, the General Instruments ALR-66A(V)1 radar-warning receiver, the Lockheed-Sanders ALQ-144 infra-red jammer, the Honeywell AAR-47 missile-warning system and the Tracor/ALE-39 chaff/flare dispenser.


Additional modifications will almost certainly be made, in the event that, the SH-2G is selected by either Australia or New Zealand, for the new ANZAC class frigate helicopter. Participation in the ANZAC competition represents a bold attempt by Kaman to expand its base beyond the secondhand FF1052 market and sell the Super Seasprite to other, more modern, navies.

The Royal Australian Navy (RAN) has a requirement for up to 27 shipboard helicopters for its new ANZAC frigates and a planned fleet of offshore patrol craft. The Royal New Zealand Navy (RNZN) needs another six helicopters as replacements for its elderly Westland Wasps.

Kaman faces strong competition in the form of the Westland Super Lynx and the Eurocopter AS.565SA Panther (Flight International, 5-11 April,P22). "We think the SH-2G has a significant cost benefit over the Lynx in any competition and certainly a vast differential over the Seahawk," argues Nichols.

Both navies have stipulated a requirement for a helicopter equipped and armed for surface surveillance and anti-surface warfare (ASW). The RNZN has also added the role of ASW, the RAN having instead decided to use its fleet of 16 S-70B-2 Seahawks for the task.

The absence of a modern targeting radar, is an area of acknowledged weakness for the SH-2G, when compared to either the Lynx or Panther. According to Nichols, Kaman is looking at replacing the helicopter's long-serving Canadian Marconi LN-66HP radar with a more up-to-date system, such as the GEC-Ferranti Seaspray.

He adds that the Seaspray has the added advantage of being compatible with the British Aerospace Sea Skua helicopter-launched anti-ship missile. While neither the Sea Skua nor AGM-119B Penguin missile has yet been fully integrated with the SH-2G, Kaman has test-fired a variety missiles from the helicopter, including the AGM-65 Maverick, the Hellfire and the Stinger.


Malaysia has a similar requirement to those of the RAN and RNZN for six new shipboard surveillance and ASW helicopters, plus a possible requirement for a further six. The country is likely to watch closely the Australian and New Zealand selections, both of which are due to be made in 1996.

Other potential SH-2G operators being pursued by Kaman are Taiwan and Turkey. The Taiwanese navy already operates three FF 1052 frigates and is expected eventually to have 12. A provisional Foreign Military Sales deal with Taiwan for 12 SH-2Gs has already fallen through once, following an unrelated local corruption scandal.

Despite competing pressure from Sikorsky for the Taiwanese navy to buy a second batch of S-70C Seahawks, Kaman is still optimistic of concluding a SH-2G deal. "That's a navy that needs the aircraft and we're working to get back in there," says Nichols

Turkey is another operator of the FF 1052-class frigate, with eight already in service and a possible ninth on its way. Kaman estimates that the FF-1052s, together with Turkey's four MEKO 200-class frigates, provide a potential requirement for up to 20 naval helicopters, plus six to eight more for shore-based training.

Nichols says: "There are other FF 1052 customers and 80m naval-vessel operators that are very interested in the SH-2G, and I'm of the opinion that, eventually, we're going to run out of available helicopters in the desert. That's a wonderful problem and one we would really like to have."

Source: Flight International