The GETL also has a turboshaft rig which uses the Gnome engine in its conventional format - i.e. with the power turbine. This rig provides a full scale test capability for helicopter nozzles and their associated installation.

The turboshaft engine is loaded through a Wessex helicopter gearbox using the compressor from another Gnome engine.

This in turn provides compressed air which can be used to carry out a number of functions.

• Downwash for helicopter studies (via a bank of small ejectors).
• Small scale flight stream simulation (via a single ejector system).
• Provision of bypass flow for the turbojet rig to allow the simulation of turbofan nozzle systems.
• Simulation of high pressure ratio nozzle systems at small scale.

The free stream rig uses exhaust flow bled from either the turboshaft or from one of the turbojet rigs.