South St Paul, Minn.-based Sierra Hotel Aero Inc., holder of the type certificate for the Navion, says it is two to three years away from bringing the aircraft back into production.
The type certificate came up for auction about 10 years ago, said Chris Gardner, owner of Sierra Hotel Aero. “At the time, we had been developing an STC to put a baggage door on the aircraft, since the original didn’t have one,” he said.
Gardner said he has always loved the design of the Navion, which made him interested in the type certificate. “My father originally had one in early 1960s, then got another one in the early 1990s, and I helped him work on the aircraft,” he recalled. “I had experience with the P-51 (Mustang), and was interested in how the airplanes were similar in design. 
The Navion was originally built in the late 1940s by North American Aviation, the manufacturer that also built the P-51. It was built to target what was seen as a growing post-war civilian market, but 83 were ordered by the Army Air Force. Ryan Aeronautical Company bought the Navion’s type certificate in 1948. Sierra Hotel Aero bought the certificate from Navion Aircraft Co. of Bowling Green, Ohio, said Gardner.
“I loved the way it looked and how it flew. And at that time, the type certificate happened to come up while I was getting things rolling to do structural work and more modifications on the aircraft,” Gardner said.
Since receiving the type certificate, Sierra Hotel Aero has upgraded the fuel system, said Gardner. “The FAA issued an airworthiness directive to replace the faulty fuel selectors, which were worn out,” he said. “We immediately got a valve design approved that was better than the original.”
Sierra Hotel Aero has also upgraded the electrical system and is working on upgrades to the powerplant, taking the engine from 185 horsepower to 310 hp, said Gardner. “We’re also working on an STC for replacement propellers,” he said. “The original propellers are either obsolete or very expensive to acquire. This will give owners more options to have newer equipment.”
Navion owners can receive everything from minor maintenance to complete factory rebuilds at Sierra Hotel Aero, said Gardner. “We utilize the original factory fixtures and tooling, which was part of the purchase of the type certificate,” he said.
“Everything we’ve done with the existing fleet is a test plan that gives us the basis to put out a new model airplane. We hold a Parts Manufacturer Approval, and can build that into a production certificate, which will lead to newer, more modern aircraft,” said Gardner. “We can take the knowledge gleaned from the original fleet and design a new model as if we’ve been the producer all along.”
Gardner estimates that around 1,200 Navions are still flying worldwide. “More people are buying them and fixing them up,” he said. “We’ve heard about Navions recently in Australia, Switzerland, and Uruguay.
Navion owners are devoted to their aircraft because of the way it flies and handles, said Gardner. “Owners also love the way it looks and its warbird heritage and it’s a very easy aircraft to fly,” he said. “It’s very versatile and a workhorse.”
