Airlander 001 Flight Test Programme

Andrew Barber, Airworthiness and Flight Test Engineer, Hybrid Air Vehicles Ltd, Technology House, Bedford, United Kingdom

Abstract

Airlander is an entirely new form of flying machine, the hybrid aircraft. Superficially an unusually shaped non-rigid airship, in fact it gains only approximately 75% of its lift from buoyancy; with the remainder being generated by lifting body aerodynamics and / or vectored engine thrust, depending on the flight phase.

Hybrid Air Vehicles is the only organisation to have built and flown a full-size and crewed hybrid aircraft. Between 2010 and 2013, in response to a US Army urgent operational requirement, British company HAV designed the Airlander in the UK, then built and flew it in the United States with the US Army as airworthiness authority. From 2014 to 2016 in England, HAV rebuilt the aircraft and implemented a flight test organisation while simultaneously moving to EASA airworthiness requirements and flight test organisation operating procedures. The aircraft was flown six more times during 2016 and 2017, significantly expanding its flight envelope and furthering the body of knowledge that will underpin the market introduction of production standard aircraft. This paper is published to share experiences of flight test from a small tightly funded company that has built and test flown under the EASA regulatory regime a large (92 metre) and complex permit-to-fly aircraft of novel concept (pressure stabilised structure, lifting body shape, four engines, vectored thrust, fly-by-light). HAV conducts flight test under the legal requirements of EU regulations but using alternative means of compliance generated by the experienced HAV team and approved by EASA against EASA acceptable means of compliance and guidance material which apply only to aeroplanes and helicopters. In addition to discussing and explaining our flight test programme to date, this paper and the associated presentation includes some essential explanations of the aircraft and its ground handling equipment.

Results and Lessons learned:

1. Designed, built, commissioned and test flew in the UK an all-new EASA regulated aircraft. We believe that this is only the second time such a programme has happened in the UK, the author was on the previous team before joining HAV.
2. Demonstrated a viable aircraft concept that, using the data collected on the seven flights of aircraft 001, we can develop predictably into a useful commercial product for many applications.
3. Demonstrated that a small focussed team can deliver under EASA and for relatively modest expenditure, flight test of a large complex aircraft using standard equipment and procedures.
4. Learned that, to maintain the optimal pace of operations, a flight test team must have a sufficiently large cadre of test pilots, FTEs, ground handling crew and data analysts. Also that formal close co-ordination, knowledge sharing and standardisation of risk management, briefing and debriefing processes are essential to success even in a small team.
5. Learned that for the efficiency and security of flight test operations, the entire test team from the pilot to the refreshments runner must study, train and rehearse together. Through this the team’s CRM, processes and communications can be thoroughly refined before the start of ground and flight testing.
6. Learned that in order to maintain the optimum pace of operations, a range of secondary factors including airfield facilities, security, public support, ancillary services and a range of other factors must be planned for and addressed in a systematic manner.
7. Learned that to maximise the benefit of each test flight, sufficient time must be allowed between sorties for extensive data analysis, model-matching and (where required) simulation upgrade to enable the best possible mission planning and technique rehearsal for the next flight.