This paper describes the problem of Hot Gas Ingestion (HGI) for vertical landing aircraft, and how it is measured and understood during aircraft development programmes. The particular problem of the F-35B JSF is discussed, with regard to the engine driven lift fan and the additional suction source this puts on the airframe.
Although the majority of HGI testing for JSF has been, and will continue to be, performed without lift fan suction, it was considered important to find some way of characterising the ingestion experienced by the lift fan as a means of reducing risk to the whole programme.
The solution was the development of a Turbine Powered Simulator (TPS), which fitted within the correct physical envelope in the aircraft model. The paper describes the conceptual design of the TPS, the detailed design of the compressor and some of the development work necessary to realise the required performance.
The developed TPS has been tested “in anger” in the BAE Systems HGI test facility. It's performance, and that of the instrumentation and data logging system, allowed the collection of data which has significantly improved understanding of lift fan ingestion, and has thus reduced the HGI risk that the project has to account.