Work continued on the wing attach lug test setup for the DarkAero 1 prototype in March. Another session of the DarkAero Aerospace Composites Course was held at the end of the month, and another contract customer aircraft made it into flight testing.

Airframe Testing
Efforts continued on the wing attach lug proof load test last month. This test represents a critical step in validating the structural integrity of the DarkAero 1 airframe before flight, ensuring it meets the demands of aerodynamic loads. Negative G loads are of particular interest during this test, due to the low wing configuration of the DarkAero 1. While positive G loads push the wing into the fuselage and hold these structures together, negative G loads pull the wing away from the fuselage and try to separate the two structures. Gust loads due to turbulence represent the flight scenario that will produce the highest negative G loads. Essentially, flying into a strong downdraft can produce peak negative G loads on the airframe. The combination of speed and wing loading of the DarkAero 1 makes this edge condition more pronounced compared to many other light aircraft, so it is an important load case to prove out on the ground.  

To ensure the most conservatively representative test possible, the lug proof load test will replicate the small amount of angular deflection imparted onto the wing attach lugs due to the elastic bending deflection of the wing. The wing root rib elastic angular deflection under lift load must be measured to accurately represent reaction loads on the fuselage wing attach lugs during the lug proof load test. The team is in the process of quantifying this deflection so it can be built into the wing attach lug test fixture.

Measuring the angular deflection per G of the wing will involve loading it with sandbags similar to how it was loaded during the wing proof load test and measuring angular deflection at specific locations at the wing root. Spanwise displacement data was previously collected during the wing proof load test, but not at the root location with sufficient resolution to be useful for the lug proof load test. Although this is a new test on the wing, structured specifically to measure angular displacement, it effectively functions as a second load test of the wing.

Prior to completing this additional measurement-driven wing load test, the wing is undergoing several updates to incorporate modifications to the center section. A fuel line pass-through is being added to the centerline of the wing, and improved hardpoints are being installed to stiffen the mount points of the flap actuation mechanism. Additionally, the construction of the honeycomb panels used in the center section was altered to better match panels that will be used on production kits. These modifications were pulled forward in the development timeline so they could be structurally validated during the test.

Courses
Session 24 of the DarkAero Aerospace Composites Course was held in March. The latest session marked a major milestone as over 200 students have attended in-person course sessions! The latest session was fully booked, reflecting continued demand for hands-on composite training. Student applications in the latest session included rockets, kit aircraft, and hang gliders. The latest session featured a new prepreg demo as well as a new course guide chapter with practical strategies to maximize quality and efficiency in production scale composites manufacturing. More in-depth information on composite repair was added to the lecture material as well. The next session will run on May 22-23. Sign up for the course using the link below:

Sign up for the DarkAero Aerospace Composites Course!

DarkAero Careers
The team at DarkAero is continuing to grow as another new manufacturing technician joined the team in early March! Interviews have been ongoing and applications for manufacturing technicians and engineers are currently being accepted. Candidates with a strong work ethic, hands-on skills, and a desire to work on challenging projects are an ideal fit for DarkAero. If you want to be part of a dedicated team designing and building new advanced aircraft, check out the DarkAero Careers page and apply today!

DarkAero Careers

Website Update
The Aircraft Page on the DarkAero website was recently updated to include a Milestones section to provide better visibility on progress made towards DarkAero 1 development as well as remaining milestones before conducting first flight and ultimately kit production. Want to see the latest milestones on the journey to first flight? Visit the updated Aircraft Page and stay tuned for the next big accomplishment!

Looking Ahead
Proof load testing of the wing attach lugs will commence once rig construction is complete and the angular deflection per G of the wing root ribs is confirmed. Expanding the team, increasing manufacturing capacity, and fulfilling contract projects will continue in parallel.