L-17 Background and Fundamentals
Posted: Thu Nov 07, 2019 12:12 am
When I first got involved with Navions, the L-17 was considered a bit of a myth. Many didn't think they actually existed, or if they did it was just a few civilian Navions in "warpaint". However, a few pictures and stories from people who knew led me to start doing deep research with the L-17 which I continue to work on when I can today.
Having a good grounding in the history and military heritage of these aircraft helps all us tell a good story about their service and honor those who built, maintained and flew them. It’s an interesting story but a somewhat convoluted one. This first installment is about the origin of the L-17, and I’ll try to cut to the chase and hit the high points.
North American Aviation (NAA) designed the NAvion to capitalize on what it thought would be a postwar general aviation boom for a four-place personal aircraft. Like all NAA products it was designed like a military aircraft, built tough but still with beautiful lines. But being built to military-type requirements had three impacts: First, it made the aircraft a tough sell against the competition. For every person that liked its rough field/short field capability, excellent outward view and good useful load there were 10 that wanted easier passenger entry and more speed – which the Beech Bonanza and others were able to provide. Second, the aircraft was expensive to build and difficult to maintain – not an issue for a military aircraft, but significant for a private owner and a new civilian manufacturer. Finally, it made the aircraft interesting to the USAF who was looking for a trainer and the U.S. Army who at that time was interested in a 4-place light personnel transport aircraft. These all play out in the history of the military version of the NAvion: The L-17.
The Army wanted the NAvion but the Key West Agreement that outlined the responsibilities of each branch of the armed forces prohibited the Army from directly procuring fixed-wing aircraft. So in 1947 an order was placed by the Air Force for 83 NAvions which were given the designation L-17 – ‘L’ being the designation for liaison (light transport and reconnaissance) aircraft at the time. These aircraft were little different than ‘civilian’ Navions and in fact when the Air Force requested a delivery, a NAvion was pulled from storage parking across the street from North American, painted grey, had military radios and lighting installed and was flown off. This is why manufacturing serial numbers of the North American L-17 are chaotic and out of order. It’s also why we see in-service photos of these aircraft in so many different colors from bare aluminum to zinc chromate to olive drab – when the Army took possession, the last color they wanted was “Air Force Grey”, so it came off. Immediately.
The Army was generally satisfied with the L-17 although they were looking for longer range and a more complete panel for instrument flying. Minor changes were made in the field, including upgrading the starter, adding a dimmer for indicator lights and a few proactive repairs and changes for the airframe. In 1948 the Air Force was working with North American on the XP-86 (later F-86 Saber Jet) and didn’t like seeing resources pulled away for the NAvion. They gave NAA an ultimatum of sorts: which aircraft would they prefer to focus on? NAA knew where the money was, and quickly put together a deal with Ryan Aeronautical to transfer the NAvion – type certificate, aircraft in progress, tooling and parts. As a sad precursor to today’s liability environment, once Ryan confirmed they had what they needed to build NAA destroyed all other documentation about the aircraft to ensure no liability remained. This is the reason there’s very little documentation from the time NAA was building the aircraft. Ryan renamed the Navion, removing the capital “A” that had identified “North American” in the NAvion name.
Part of the deal for Ryan was an order for 158 new L-17s with enhanced capabilities including a “full gyro” panel, an underseat auxiliary fuel tank and several other minor changes. They also provided parts to retrofit a little less than half (33) of existing North American L-17s with these new features, with the installation work being done by Schweitzer Aircraft Company. To keep all these aircraft straight original NAA aircraft were designated L-17A, the new Ryan aircraft were designated L-17B and the Schweitzer upgraded NAA aircraft were designated L-17C. Ryan started production, building these 158 aircraft in a single, sequential production run, hoping to generate cash flow for their civilian production as well. At the last minute the Air Force added an order for 5 additional aircraft for the Hellenic (Greek) Air Force and Ryan continued the production run, ultimately producing 163 L-17B aircraft.
The operational story begins with these 246 aircraft representing about 10% of overall Navion production. As an origin story, it doesn’t read like a blockbuster movie script. But the L-17 would go on to serve with distinction in a broad variety of roles, some traditional and some very surprising.
That’s the subject of the second half of this article: Myths and Legends.
Having a good grounding in the history and military heritage of these aircraft helps all us tell a good story about their service and honor those who built, maintained and flew them. It’s an interesting story but a somewhat convoluted one. This first installment is about the origin of the L-17, and I’ll try to cut to the chase and hit the high points.
North American Aviation (NAA) designed the NAvion to capitalize on what it thought would be a postwar general aviation boom for a four-place personal aircraft. Like all NAA products it was designed like a military aircraft, built tough but still with beautiful lines. But being built to military-type requirements had three impacts: First, it made the aircraft a tough sell against the competition. For every person that liked its rough field/short field capability, excellent outward view and good useful load there were 10 that wanted easier passenger entry and more speed – which the Beech Bonanza and others were able to provide. Second, the aircraft was expensive to build and difficult to maintain – not an issue for a military aircraft, but significant for a private owner and a new civilian manufacturer. Finally, it made the aircraft interesting to the USAF who was looking for a trainer and the U.S. Army who at that time was interested in a 4-place light personnel transport aircraft. These all play out in the history of the military version of the NAvion: The L-17.
The Army wanted the NAvion but the Key West Agreement that outlined the responsibilities of each branch of the armed forces prohibited the Army from directly procuring fixed-wing aircraft. So in 1947 an order was placed by the Air Force for 83 NAvions which were given the designation L-17 – ‘L’ being the designation for liaison (light transport and reconnaissance) aircraft at the time. These aircraft were little different than ‘civilian’ Navions and in fact when the Air Force requested a delivery, a NAvion was pulled from storage parking across the street from North American, painted grey, had military radios and lighting installed and was flown off. This is why manufacturing serial numbers of the North American L-17 are chaotic and out of order. It’s also why we see in-service photos of these aircraft in so many different colors from bare aluminum to zinc chromate to olive drab – when the Army took possession, the last color they wanted was “Air Force Grey”, so it came off. Immediately.
The Army was generally satisfied with the L-17 although they were looking for longer range and a more complete panel for instrument flying. Minor changes were made in the field, including upgrading the starter, adding a dimmer for indicator lights and a few proactive repairs and changes for the airframe. In 1948 the Air Force was working with North American on the XP-86 (later F-86 Saber Jet) and didn’t like seeing resources pulled away for the NAvion. They gave NAA an ultimatum of sorts: which aircraft would they prefer to focus on? NAA knew where the money was, and quickly put together a deal with Ryan Aeronautical to transfer the NAvion – type certificate, aircraft in progress, tooling and parts. As a sad precursor to today’s liability environment, once Ryan confirmed they had what they needed to build NAA destroyed all other documentation about the aircraft to ensure no liability remained. This is the reason there’s very little documentation from the time NAA was building the aircraft. Ryan renamed the Navion, removing the capital “A” that had identified “North American” in the NAvion name.
Part of the deal for Ryan was an order for 158 new L-17s with enhanced capabilities including a “full gyro” panel, an underseat auxiliary fuel tank and several other minor changes. They also provided parts to retrofit a little less than half (33) of existing North American L-17s with these new features, with the installation work being done by Schweitzer Aircraft Company. To keep all these aircraft straight original NAA aircraft were designated L-17A, the new Ryan aircraft were designated L-17B and the Schweitzer upgraded NAA aircraft were designated L-17C. Ryan started production, building these 158 aircraft in a single, sequential production run, hoping to generate cash flow for their civilian production as well. At the last minute the Air Force added an order for 5 additional aircraft for the Hellenic (Greek) Air Force and Ryan continued the production run, ultimately producing 163 L-17B aircraft.
The operational story begins with these 246 aircraft representing about 10% of overall Navion production. As an origin story, it doesn’t read like a blockbuster movie script. But the L-17 would go on to serve with distinction in a broad variety of roles, some traditional and some very surprising.
That’s the subject of the second half of this article: Myths and Legends.