Hybrid propulsion system for unmanned aerial systems is unveiled by EADS Innovation Works

13 September 2012

EADS Innovation Works’ presence at the 2012 ILA Berlin Air Show includes a hybrid power system concept for the TANAN™ tactical unmanned aerial system (UAS) of EADS’ Cassidian division.

This hybrid approach combines a rotary combustion engine operating on heavy fuel (diesel or kerosene) with electric propulsion, enabling improvements in the UAS’ operational and mission capabilities.

EADS Innovation Works’ concept consists of the following main elements: the heavy-fuel-powered Wankel SuperTec rotary engine with a shaft-coupled electric generator; electric motor drives for the main and tail rotors; a power train control unit for electric power management; and a battery that provides energy for both the aircraft’s electric propulsion system and its on-board systems.



The components of EADS Innovation Works’ hybrid power system concept are shown full-scale in a schematic representation of the TANAN tactical unmanned aerial system, which is part of EADS’ pavilion at the ILA Berlin Air Show.

Advantages of the hybrid system will be either longer range and endurance, or an increased payload capability due to improved propulsive efficiency when compared to a diesel piston engine with its mechanical rotor drives. Another benefit comes with the hybrid configuration’s reduced system complexity and increased operational reliability, achieved through the elimination of the gearbox and driveshaft utilized on current-generation UAS rotorcraft.

An important operational bonus is the capability to shut down TANAN’s combustion engine while the UAS flies on battery power only, according to Juergen Steinwandel, EADS Innovation Works’ Senior Expert, Technical Physics. This is beneficial to TANAN’s survivability in critical operational flight phases, as it drastically reduces the UAS’ infrared and noise signatures.

The TANAN concept study detailed at the ILA Berlin Air Show is part of EADS Innovation Works’ on-going hybrid and electrical propulsion system research. This activity also has involved the hybrid concept study for a full-scale passenger helicopter (which was unveiled at the 2010 ILA Berlin Airshow), the successful development of a Cri-Cri ultralight modified as the world’s first four-engine all-electric aerobatic aircraft (in flight validation since 2010), on-going demonstration flights of the German-developed eGenius hybrid electric motor glider – for which EADS Innovation Works developed the battery system; and flight testing of a short-range mini-unmanned aerial vehicle from the EADS Cassidian division, in which EADS Innovation Works integrated an advanced fuel cell.

Prior to the current hybrid concept work for TANAN, EADS Innovation Works designed and carried out the integration of a piston diesel engine into the TANAN airframe, replacing the UAS’ original gasoline-fuelled two-stroke engine. As a result, Cassidian’s TANAN 300 version became the first diesel-powered rotorcraft unmanned aerial vehicle, capable of completing eight-hour missions over a 180 km. range with a 50 kg. payload.

The use of an engine operating on heavy fuel such as diesel is required for an aircraft’s deployment on ships, as gasoline fuel is strictly prohibited in this environment. Diesel engines also are beneficial for land-based operations, where heavy fuel is widely available through the supply chains of the military forces.

Cassidian is offering the TANAN 300 for airborne observation in a large variety of maritime and land missions, equipped with electro-optical and infra-red high-definition sensors.