Lilium has selected aerostructures and aero-engine components group Aciturri to produce primary composite structures for its Lilium Jet eVTOL aircraft. The companies today announced what they described as a long-term partnership for manufacturing the airframe for the all-electric model, which is expected to be in series production by around the end of 2024.
Spain-based Aciturri’s engineering team will work closely with its counterparts at Lilium on finalizing the design of the composite airframe structures, as well as planning the manufacturing process. The structures, including the fuselage, wing, canard, and spars, will be made at its plant on Boecillo, around 125 miles northwest of Madrid, before being transported to Lilium’s purpose-built final assembly line at Wessling in southern Germany. These will be made using carbon fiber composite materials supplied by Toray Industries, with which Lilium signed a contract in May 2020. Lilium is now looking to procure other components, including flaps and doors.
“We scanned the whole supply base in Europe and chose Aciturri from a shortlist of three,” Lilium’s chief program officer, Yves Yemsi, told FutureFlight. “We are trusting them a lot [in terms of responsibility] because this contract goes beyond just the technology.”
Yemsi, who before joining Lilium in August 2019 was senior vice president for procurement programs and supply chain with Airbus, has worked with Aciturri before on programs such as the A350 widebody airliner. The tier-one supplier also supports other major airframers, including Boeing and Embraer, and was an earlier adopter of composite materials in the aerospace sector.
Even though Lilium is working toward an aggressive goal of having the aircraft in commercial service in 2025, Yemsi insisted that preparations for the production phase will be made with safety and long-term program viability as priorities. “The whole program is being orchestrated around a series of maturity cases,” he explained. “Composite and structures work is a key element of this, and it involves long lead times, so we want to be sure we are ready for prototyping and then serial production, de-risking it.”
The final prototype for the Lilium is still in the preliminary design phase and the company has not declared when it will be ready to start test flying. It has acknowledged that the aircraft is expected to be larger than the five-seat technology demonstrator that was destroyed by fire during maintenance work on Feb. 27, 2020, nine months after starting flight testing. Multiple reports have indicated that the new version will be a seven-seater, and the company has not disputed this prediction.
According to Yemsi, Lilium has purposely deferred completing the preliminary design to take account of the certification requirements of both EASA and the FAA, from which it is seeking concurrent approval on both sides of the Atlantic. EASA, with which the company has been working since 2017, is close to issuing the final means of compliance and requirements for the Special Condition-VTOL rules that it first issued in mid-2019.
Yemsi stressed that the top management of Lilium is completely aligned as to when flight testing of the full-scale prototype can begin. “Safety and quality are what matter above all else, and there is no pressure [to accelerate the pace],” he said.
Aciturri commercial director Vicente Brisa said that with three decades of experience in the aerostructures business, the group is up to the challenge posed by this new category of aircraft. “This is not the first time we have had a risk-sharing partnership, and we have already had this level of responsibility for design to manufacturing with the A350 and A380,” he told FutureFlight.
In the wake of the Covid pandemic’s decimating impact on the air transport industry, Aciturri has welcomed the opportunity to diversify into the fast-emerging eVTOL sector, even though its initial contact with Lilium predates Covid.
“We face some tight schedules to make deliveries and then some challenges in scaling up production, but we have put a large team on this project, and they are already working on this at the early stages to be ready for when the higher volumes come,” Brisa concluded.