The making of the SFD model

The goal was to develop a highly representative scaled aircraft of an actual aircraft, to show that it can be used for obtaining flight-mechanics characteristics that are representative of the full-scale aircraft. This will bring a very cost-efficient approach for developing radical new aircraft, as needed for more sustainable aviation. The scale model is equipped with very accurate  flight test instrumentation to carry out measurements during the tests.

Developing, building and preparing the SFD 

The Scaled Flight Testing approach is validated by a consolidated team of 4 entities providing specific expertise. ONERA is the overall project lead for setting-up and coordinating the entire validation process, and also investigates the scaling impact and will define the final transposition laws between the scaled vehicle and its full-scale reference. Royal NLR is the SFD operator, is in charge of SFD design, manufacturing, integration, ground testing, and flight operations as well as the complete Flight Test Instrumentation. CIRA designed, manufactured, and tested the SFD’s Guidance Navigation and Control system as well as the Remote Pilot Ground Station. CIRA is also in charge of mission flight testing taking place in Italy. Airbus provided the demonstration goals at the beginning of the project and supports the various phases of SFD development throughout the project.

The scaled model was built by Royal NLR together with Orange Aerospace. The work included avionics subsystem design & manufacturing & test, SFD airframe (wing & fuselage) design & manufacturing & assembly & integration (with Orange Aerospace), integration of Flight Test Instrumentation (developed by NLR). Together with CIRA, NLR did the development of and integration with the Ground Control System. The SFD system integration and test, and wind tunnel tests took place at the DNW LLF wind tunnel in Marknesse (NL) in April 2021.

NLR prepared the qualification of an operational concept to obtain an authorisation to fly, and training of the flight crew. High-speed taxi tests were performed at Deelen (NL) in November 2021. A Flight Readiness Review has been conducted successfully, with Airbus as an important reviewer. The test flights of the SFD flight as part of a qualification campaign at Deelen were carried out in March 2022. The SFD is operated by the NLR flight crew from a cockpit on the ground. The mission flight campaign in Italy is planned for mid-2022.

Data of the Scaled Flight Demonstrator 

• 1:8.5 scale model based on an Airbus A320
• Wingspan: 4 metres
• Take-off mass: 140 kg
• Cruise speed: 85 kts (160 km/u)
• Duration maiden flight: 9 minutes