Andrzej Jeziorski/MUNICH

THE GERMAN Government has confirmed that it will fund a new Eurocopter EC 135-based helicopter technology demonstrator, to fly by the end of 1998.

The aircraft, called Helicopter Simulator for Technology, Operations and Research (HeSTOR), will replace the Eurocopter BO 105-based Advanced Technology Testing Helicopter System (ATTHeS), which crashed on 19 May.

The specification of the HeSTOR is now being decided, following the completion of the Active Control Technology Demonstrator Flying Helicopter Simulator (ACT/FHS) concept study, carried out jointly by the German Aerospace Research Establishment (DLR) and Eurocopter Deutschland.

According to DLR Flight Mechanics Institute director Peter Hamel, the helicopter's roles will include in-flight simulation of various helicopter types, technology demonstration for industry, and operational investigations for the defence ministry's WTD-61 flight-test unit.

No decision has been made on whether the helicopter's digital flight-control system will be fly-by-wire or fly-by-light, although Hamel says that the results of the ACT/FHS study call for a quadruplex system.

He confirms that the HeSTOR will be based on the new, German-produced EC 135 airframe.

The development programme, estimated to be worth between DM40 million ($28.5 million) and DM50 million, is jointly funded by the Federal Ministry of Defence, the DLR and Eurocopter. Programme sources say that the DLR, which will operate the helicopter, is contributing DM10 million, with Eurocopter contributing DM7 million.

Lindenberg-based Liebherr Aero-Technik is involved as a subcontractor, supplying smart actuators for the flight controls. Hamel says that the French Government will also invest in the programme once the helicopter is operational, with a view to using the HeSTOR as a defence-research platform.

The DLR will manage the programme on behalf of the BWB defence procurement agency.

Accident investigators at the Federal Aviation Office (LBA) say that the loss of the DLR's long-serving ATTHeS research platform was caused by the failure of the flexible coupling between the tail rotor and the main rotor.

While no final accident report has been issued, the failure appears to have been caused by cables becoming entangled in the coupling. The LBA says that it believes these cables were part of the ATTHeS's unique equipment configuration, and has no safety implications for other operational BO 105s.

Source: Flight International