At @HeartAerospace, @AndersForslund1 built the company one material milestone at a time, using each one to earn the credibility and capital to build the next. “We really had no technology. I came to YC Demo Day with a little 3D-printed model.” “We went from having the LOIs to building the 400 kilowatt motor, which was the size of a small jet engine. That in turn attracted actual pre-orders, and then that attracted more capital.” Their first major airline customer came through the spam…