Auxiliary  Propulsion and Power Unit

Proposal Acronym    : APPU

Project Lead               : Dr. A. (Arvind) Gangoli Rao and Prof.dr. ir. L.L.M. (Leo) Veldhuis

Affiliation                   : Faculty of Aerospace Engineering, TU Delft, The Netherlands          

Project Partners        : TKI (ministry of economic affairs, Govt. Netherlands), SAFRAN group, Airbus and Rotterdam the Hague Innovation Airport (RHIA)

Project Duration       :  3 years from 1/6/2020 to 31/8/2023

Total project budget : € 2.045.000 (PPS grant: € 1.640.000; Industrial Co-funding: € 405.000)

hat is the project:

The EU Flight Path 2050 Goals aim at dramatically reducing the climate impact of aviation. While drastic changes in the aircraft configuration are only possible in the latter half of this century, the climate impact of aviation has to be tackled soon. The APPU project aims at significantly cutting local air emissions while significantly reducing the global impact of aviation by introducing “Energy Mix” into aviation and enhancing aircraft efficiency by application of novel boundary layer ingestion (BLI) technology to the workhorse of aviation, the A320, thereby reducing the risks and the time to market introduction drastically. The proposed APPU is a novel system that replaces the traditional APU with a multifunctional state of the art gas turbine fuelled by Hydrogen and powering a variable pitch open rotor propulsion system at the aft end of the fuselage in a BLI configuration.

Why is it important (for society, industry)

The short to medium rage (SMR) aircraft, like A319/A320/A321, are the backbone of civil aviation and are therefore responsible for a significant portion of emissions from aviation (around 50 %). While small aircraft can be made electric or hybrid electric, these solutions are not scalable and are not applicable to aircraft like A320 family. The APPU project will introduce energy mix in aviation by allowing a scalable, feasible, producible and economical aircraft that will use hydrogen in a synergistic way along with other innovative technologies. The APPU system that will be developed in the project has the potential to cut LTO emissions by half.

Project goals:

  • Design a BLI system for A320 type of Aircraft
  • Design and test an open rotor propulsion system operating in boundary layer ingestion regime
  • Design and test a hydrogen combustor for the APPU engine
  • Design and optimize the aircraft empennage and performance for next generation A320 with the APPU system
  • Investigate storage solutions for H2 in an aircraft