My test flight in Continental Motors’ developmental Cirrus SR22 was among the most unusual and interesting of my career. That was in part because I was testing a major mod of an airplane in which I have a lot of flying experience, and in part because I was glimpsing into the future by flying a big-bore-powered airplane using unleaded fuel.
The airplane I flew was topped off with 94UL in Mobile, Alabama, that morning. By the time it made it out to Austin, Texas, we still had a couple of hours of unleaded fuel, enough to see how the TSIO-550 performed on 100-No-Lead before adding 100LL for the remainder of the flight.
