The heavy fuel engines powering the RAN’s two Schiebel S-100 Camcopter unmanned aerial systems (UAS) have failed to meet Navy’s requirement of six hour’s endurance with a 20kg payload and are to be replaced by a new design in late September.
Andrew Watson, general manager Schiebel Pacific, confirmed to ADM that the two JP5-powered S-100s delivered to the RAN as lead customer in 2017 had been replaced by the company late last year with two aviation gasoline (avgas)-powered S-100s.
The RAN had started ship-borne evaluation trials under Navy Minor Project 1942 of the two JP5-powered heavy-fuel variants in early 2018, replacing a single S-100 on loan that was powered by a Diamond piston engine whose avgas fuel was deemed unsuitable for ship-borne evaluations because of its relatively low flashpoint.
To meet the RAN’s requirements, Schiebel replaced the Diamond engine with a two-disc Rotron 600, sourced from UK company Rotron and modified in-house. The Rotron engine accepts JP-5, a kerosene-based fuel with a flash point above 60 degrees Celsius.
Watson said that endurance with the Rotron 600 had peaked during the 2018 trials at about five hours with a 20kg payload. It had been expected to at least equal (if not better) the six hours delivered by the Diamond-powered S-100.
According to Watson, two replacement air vehicles powered by a new S-2 heavy fuel engine designed by Schiebel would be delivered to the RAN in late September and would replace the avgas variants after completing an acceptance program.
Captain Matthew Royals, RAN Director of Aviation, said the two avgas-fuelled S-100s had continued flight trials involving the RAN’s 2,935-ton civilian-crewed multi-role aviation training vessel (MATV) Sycamore.
These trials would move to the Anzac-class frigates as soon as possible after the S-2-powered air vehicles arrived and were cleared for ship-borne evaluations, he stated.
The parameters being established for both the MATV and the Anzac-class include safe take-off, operating and landing limits under various sea states and lighting conditions. UAS handling, storage, and emergency procedures are also involved.
During recent trials both S-100 variants have been fitted with L3 Wescam’s MX-10 multi-sensor, multi-spectral imaging system.