Germany’s DLR To Build VTOL Crash And Impact Test Center
German aerospace center DLR plans to build a new indoor facility for full-scale crash and impact testing of helicopters and electric vertical-takeoff-and-landing (eVTOL) aircraft.
The center is designed to support both research and certification testing.
To be located in the Stuttgart area near DLR’s Institute of Structures and Design, the facility will be constructed beginning this year and operated over the next five years with funding from the Baden-Wuerttemberg region.
CITE will provide “a unique indoor infrastructure for full-scale testing to support safety and certification for the next generation of aviation,” Florian Antrack, DLR project manager, says. The center will be able to test aircraft up to 4,000 kg (8,800 lb.).
The new facility will have three elements. CITE-Crash will include a drop tower for vertical crash testing and a dynamic test platform to test full-scale aircraft under multidirectional crash conditions, impacting with both vertical and horizontal velocity.
CITE-Impact will provide gas gun facilities to reproduce impact incidents, including bird and drone strikes. Antrack says DLR has developed the capability to perform more accurate and repeatable bird-strike testing using artificial birds.
The third element, CITE-Digital, is a data management system that will centralize test and simulation data on a single platform to easily interlink virtual and physical environments and allow collaboration during design, including with external partners.
CITE will be one of only two such test environments—the other being the Landing and Impact Research Facility at NASA Langley Research Center in Virginia, Antrack told the Vertical Flight Society’s Forum 79 symposium in West Palm Beach, Florida, on May 16.
NASA’s facility was most recently used to conduct a crash test of a full-scale eVTOL concept vehicle—with surprising results. The test in December 2022 resulted in unexpectedly severe damage.
The test involved the full-scale, all-composite fuselage of NASA’s concept design for a six-passenger lift-plus-cruise eVTOL, which was dropped from the impact gantry to measure loads on the dummy occupants in what was designed to be a severe but survivable crash.
“So when it shattered, we were very, very surprised. That did not match our pre-test calculations and was really rather shocking,” Susan Gorton, NASA’s Revolutionary Vertical Lift Technology project lead, told the conference.
“What we learned from that is that our modeling was not high enough fidelity. And within three months, our modelers have improved their modeling techniques,” Gorton said, adding that modeling of both composite structures and crash test dummies has been improved.
“We can now match that test data,” she said.
NASA plans to repeat the crash test in 2024 with a second eVTOL airframe. “We will make predictions for another set of conditions, and we will drop it and see if we match. Then we’ll know that new way of modeling is correct,” Gorton added.
Once the CITE facility in Germany is compete, Antrack said DLR plans to work with French research agency Onera under their long-running rotorcraft research cooperation. Onera’s focus is computational modeling, and data from CITE tests will be used to validate the models, Arnaud Le Pape, Onera rotorcraft program director, said on the sidelines of the conference.