Use of an Engineering Simulator to Inform Design and Flight Test Planning of a Novel Hybrid Aircraft

Warwick Bradfield, Hybrid Air Vehicles Ltd., Technology House, 239 Ampthill Road, Bedford, MK42 9QG, UK
R. Nathanael West, Hybrid Air Vehicles Ltd., Technology House, 239 Ampthill Road, Bedford, MK42 9QG, UK

Abstract

Airlander 10 is a hybrid aircraft designed by Hybrid Air Vehicles (HAV), combining buoyancy from helium, aerodynamic lift, and vectored thrust. Airlander 10 operates at a higher static heaviness compared to traditional airships and therefore requires additional aerodynamic lift, which is provided by its lifting-body-shaped hull. Directed propulsion is achieved through rotation of the unducted front propulsors in pitch, ducted rear propulsors with vectoring vanes, and a bow thruster. All these attributes make Airlander 10 a new technology in certification and flight test. HAV has developed an in-house engineering simulator to assist in design evaluation, modelling of aircraft behaviour and performance, and preparation of pilots and FTEs for flight testing. The simulator is underpinned by a custom 6 degrees-of-freedom model which computes the interactions of all the key systems necessary to simulate the aircraft flight dynamics. At HAV, the pilot-in-the-loop simulation provided by the engineering simulator has been indispensable in preparation of past and future flight testing, development of operational strategies, and guidance of the design process. This paper gives an example of how simulated flight test was used to develop landing techniques, where the simulator’s noise-free FTI data provided unique advantages compared to FTI data from actual flight test. Furthermore the simulator can be used to model the aircraft’s response to system failures, thereby informing risk assessments for the flight test programme. This paper describes how the simulator can contribute to risk assessments of flight tests which attempt to replicate a failure scenario.