When the Alamo Liaison Group (ALG) was formed in 1981, by a group of San Antonio area aviators, its mission was to acquire and restore liaison aircraft flown by the U.S. military in World War II. These aircraft were to be kept in flying condition, following their recovery and reconstruction, for the purpose of honoring those who operated them and all who served.

Led by Hardy Cannon, a master mechanic, ALG completed in 1982 the restoration of a 1941 Stinson L-1, a 1941 Taylorcraft L-2, a 1942 Aeronca L-3, a 1942 Piper L-4, a 1942 Stinson L-5, and a 1942 Interstate L-6. This collection of “L-birds” (L for liaison) represented the introductory class in a progression of light aircraft used principally by the U.S. Army Air Forces. The liaison class would continue to evolve into the 1960s. As warbirds go, the L-birds were generally smaller and often unarmed. They were optimized for specific tasks and all featured short takeoff and landing (STOL) capabilities. Other single-engine aircraft carrying the L-bird moniker include:
- L-7 Universal/Monocoupe/Luscombe pre and post-WWII
- L-8 Interstate Cadet model S-1A (L-6 was model S-1B1)
- L-9 Stinson Voyager 3-seat, yet smaller than L-5
- L-10 Ryan 3-seat, only one served
- L-11 Bellanca 31-50 Senior Skyrocket, only one impressed
- L-12 Stinson Reliant, two each of the SR.5A and SR.7B
- L-13 Stinson-Vultee/Convair with folding wing
- L-14 Piper J-5 Cruiser 3-seat
- L-15 Boeing with its unique tailboom and dual downward-mounted stabilizers
- L-16 Aeronca Champion/Champ with slightly better performance than the L-3 Chief
- L-17 & L-22 North American/Ryan Navion & Super Navion
- L-18 & L-21 Piper Super Cub, a higher performing L-4 Cub
- L-19 Cessna Bird Dog, all-metal
- L-20 de Havilland Canada Beaver 7-seat, similar in size to L-1 with higher payload
- L-24 & L-28 Helio Courier 6-seat
- L-60 Czechoslovakian Brigadýr 4-seat.
The most substantial, and certainly exceptional, among these aircraft was the Stinson L-1 Vigilant. The L-1 derived from Stinson Aircraft Corporation’s civilian Model 74. It was identified by the military as O-49, originally among the class of observation aircraft (O for observation). In April 1942, the O-49 turned L-1 when the liaison designation ascended that of observation.

The L-1 was envisioned as a highly versatile air defense instrument. Its requisition came with a monumental list of specifications and capabilities. Its design engaged with every demand of a vigilant military. However, the grand concept proved itself overindulgent. Ground forces, the predominant operator of liaison aircraft, found the L-1 to be complex and costly.
The liaison aircraft function demanded simplicity. L-birds were tasked with flying from point to point, often on short hops. They gathered, delivered, and reported stores and information. From their manufacture to delivery in the field, to the verity of improvised maintenance and the absolute necessity of organic (Organic refers to the ground arms desire to have complete control of the use of their planes while being manned by personnel from the units they served and stationed as close to them as possible.) pilot/crew operations, the L-1 was a bear when the Army needed a cub.
As the role played out, succeeding L-bird models would prove ideal to the task. They were smaller and lighter, yet delivered results with greater and weightier outcomes than the L-1. Demand for liaison aircraft engagement still outstretched the ability to supply them. Nevertheless, L-birds were produced by the tens of thousands.
The L-1 was superseded in procurement by vast numbers of the Piper L-4 (in addition to similar Aeronca and Taylorcraft models) and the later Stinson model L-5 Sentinel. Nearly 4,000 L-5 examples were produced. Peak production of the L-4 was one aircraft every 20 minutes with over 5,000 going to the military. Piper delivered over 19,000 of the L-4 / J-3 (Many J-3 models went to various War Training School operators.) type between 1938 and 1947. The smaller L-birds earned the nicknames “Puddle-jumper,” “Grasshopper” and “Flying Jeep.”
The L-1 was by no means inferior. It was extremely well-conceived, well-built, well-equipped, and performed to the illustrative standard Fieseler Storch that spawned its creation. The L-1 served with U.S. and Allied forces beginning in 1941, and up to 1947 with the Royal Air Force. The proliferation of simplicity, and ubiquity, within the liaison function necessitated its demise. The L-1 was the largest L-bird used in World War II.

The Stinson L-1 Vigilant was used throughout the world, seeing service in Europe, Africa, Asia, and Alaska. Its primary missions included running supplies, transporting key personnel, and medical evacuation. The L-1 was also used in diverse roles such as towing training gliders, spotting artillery, and special espionage flights. Some were modified to perform amphibious air ambulance missions.
Origins
The Stinson O-49 / L-1 was conceived in response to a 1938 U.S. Army Air Corps (The U.S. Army Air Corps became the U.S. Army Air Forces on June 20, 1941.) competition for a two-seat light observation aircraft. When a German-manufactured Fieseler Storch was demonstrated at the Cleveland Air Races—a national air race competition taking place in the U.S. since 1920—the Air Corps revised its specifications in an attempt to match the performance of the impressive Storch.
Stinson Aircraft Corporation of Wayne, Michigan, won the $1.5 million contract with the O-49, beating eleven competitors. A second contract was later awarded to Stinson, by that time a division of Vultee Aircraft Corporation, for the O-49A which had a slightly longer fuselage and other equipment changes. In all, 324 iterations of the Stinson O-49 / L-1 were built.
The Stinson Model 74, on which the O-49 / L-1 was based, was a high-wing monoplane with a single radial engine. It incorporated pilot-operated slotted flaps for low speed and high lift performance. It was built with full-span automatic slats (manufactured by Handley Page of the U.K.) on the leading edge of its wings. Both design features improved the airplane’s angle of attack and stall speed.
The aircraft was built of steel tubing and fabric, with the fuselage forward of the wing covered in sheet metal. Control surfaces and the empennage were fabric-covered stainless steel. The Lycoming powerplant, capable of 295 hp, was hand-cranked inertia starting and fitted with a Hamilton Standard constant speed propeller. First flight of the Model V-74 / YO-49 designated prototype took place on July 15, 1940.
The Vigilant was capable of stopping in less than its own length, and could maintain stable flight at 31 miles per hour. Coming in at a steep angle, then leveling off, it could land at 10 miles per hour. Anecdotally, it was said to be capable of backwards flight in a strong headwind. While the lighter L-birds could achieve the same, such performance was stunning for the larger, heavier L-1.
Up to 17 L-1 and 96 L-1A aircraft were allocated to the British Royal Air Force under the Lend-Lease Act of 1941. (Lend-Lease was enacted to aid U.S. allies in the war against Germany, with the donation of nearly 9,000 combat aircraft flown from Great Falls, Montana to the Eastern Front via Canada, Alaska and Siberia.) The RAF designated these aircraft the Vigilant Mk I and Vigilant Mk II respectively.
In Canada, General Harry Crerar, Commander of the First Canadian Army in Europe during World War II, maintained a Vigilant for personal use. George S. Patton was provided a Stinson O-49 and a personal Air Corps pilot in 1941, during his participation in the Louisiana Maneuvers. He also flew a privately owned Stinson 10A—a model that would later become the L-9. In October 1944 at Burtonwood, a former joint RAF/USAAF base in the U.K., two L-1C litter-equipped air evacuation models were modified by the installation of a rear seat in place of the litter and intended for General Dwight D. Eisenhower’s personal use. (The Fighting Grasshoppers by Kenneth Wakefield, p. 36.)
The ALG Restoration
Throughout the years a number of L-birds have operated from Cannon Field, home to the now renamed Alamo Liaison Squadron (ALS). These aircraft included actual L-birds with military history and other modern constructions resembling warbirds. Among them, the L-1 was a rarity. Keeping it flying was an onerous task. Its restoration proved, above all, a treasure hunt for the one-of-a-kind systems, accessories and equipment that made it unique. Despite the L-1’s absence today, ALS is proud to claim its revival began here.
Thankfully, the restoration undertaken by ALG on L-1 serial number 41-18915 in its 41st year survived another 37 years. Its history traced, the airplane now resides at the Alaska Aviation Museum on Lake Hood Seaplane Base in Anchorage, Alaska.
This aircraft (s/n 41-18915) was first constructed in 1941 as an O-49A, a lengthened (by 13 inches) version of the original O-49. It was later configured as a model L-1F which incorporated amphibious pontoon floats (manufactured by Edo Aircraft Corporation) and an ambulance configuration. Only five such conversions were done. The plane was put into service with the U.S. Army Air Forces on December 22, 1941—two weeks after the Attack on Pearl Harbor.
After serving in several southern states, in military exercises and training, 41-18915 was shipped to Alaska for service with the 11th Air Force at Fairbanks and Anchorage in 1944. It was stationed in Nome, participating in search and rescue operations as part of the Lend-Lease Act. It likely also performed supply hops and special espionage missions behind Japanese lines for the 1st Air Commando during the 1944–1945 China and Burma campaigns. (World War II Journal #15: U.S. Warplanes by Ray Merriam, p.27.)
Following WWII, 41-18915 was sold in 1946 by the War Assets Administration at its last base of operations in Alaska. It began use with the U.S. Fish and Wildlife Service and gained civilian registry as N704 operating in Anchorage, Alaska from 1947–1953.
As an L-1A (in parity with its O-49A military designation), 41-18915 was registered as N704E by Lawrence E. Flahart of Anchorage, Alaska on December 6, 1953 (until 1972). It was modified as a cabin airplane by replacing the “greenhouse” with a solid top. (World War II Journal, Merriam, p.27. Greenhouse refers to extended cabin windows both overhead and aft. This was done to improve visibility for the rear-seated occupant.)

The “L-1F” floatplane was withdrawn from use between 1977 and 1981 by James Harrower of Anchorage, Alaska. It was subsequently bought by Bill Stratton and, with floats removed and wheels installed, flown to San Antonio, Texas on May 27, 1982. Stratton also purchased what existed of N1377B (an L-1 s/n 41-19015 later restored by James P. Harker of Blaine, Minnesota ) for spare parts.
San Antonio Express-News article by Joe Fohn, May 28, 1982: One of the group’s rarest acquisitions consists of a tangle of tubing wires and rotted canvas. Four known. It is an L-1, the largest liaison plane used and one of four known to exist anywhere. ALG members found it after it had lain for decades in the Alaskan wilderness. Within a year, Stratton said, they hope to have it flying alongside the other five planes. Stratton said the group wrote to Wright-Patterson Air Force Base’s Air Force Museum for a photograph of an L-1 to guide restoration. “The picture they sent us was our plane. It had the same tail number,” Stratton smiled.
The aircraft underwent restoration by ALG in 1982. “The big Stinson was taken down to the bare air frame and sandblasted to bare metal so every part could be inspected. Slowly, the reassembly began as each additional part was refinished and installed,” Vintage Airplane magazine February 1984. After a nearly six-year grounding, the L-1 was flying again, as a landplane, to airshows and events:





Flying Times, a publication of Kelly Air Force Base, August 3, 1984: A ride in a vintage 1941 Vultee L-1 “Vigilant” liaison plane is not typical of a ride in other small aircraft… As he is cleared for take-off, Straw revs the already-deafening engine and works the exposed cables that operate the flaps. The L-1 leaves the ground at only 30 mph, and about 10 seconds later it has climbed to a respectable altitude. The aircraft soars high above San Antonio – all the while it feels like a strong wind could blow the light plane over… In an abrupt landing, the L-1 straightens out and slows to about 30 mph. Rubber kisses the pavement and the plane shudders and shakes to a halt.
Hill Country Recorder September 19, 1984, by Roger L. Berry: The ALG L-1 was the only restored plane of its type left in the world. The USAAF [U.S. Army Air Force] flew them in Burma (Air Commandos), Europe, Alaska, and Hawaii (several were destroyed by the Japanese in the Pearl Harbor Attack). This “one-of-a-kind” aircraft has been restored in the markings of Bellows Field, Hawaii, December 7, 1941. Alamo Liaison Group flies over Boerne during the Kendall County Fair Parade.








Dave Smith of the International Liaison Pilot and Aircraft Association, San Antonio, Texas, registered the aircraft (N704E) in April 1985 (until 1992).

Flying Magazine October 1987, by Gordon Baxter: The big L-1 almost seemed to hover at its touchdown speed of 30 knots, slower than all the other liaisons. Load hauling in the roomy cabin seemed to be limited only by what the landing gear could stand. The gear was a weak point in the design of the L-1, and with its greater weight the big monoplane did not hop and skip over ground irregularities as the lighter liaisons did, but collapsed its landing gear. First in use as a liaison, the L-1 stayed on the longest [in government service]. In the postwar years there was a rush for the surplus airplanes, then all but the Interstate and L-1 went back into long, happy lives.
Express-News October 18, 1987, by Nora Lopez: They were called called the “Jungle Angels” during World War II since they swooped down from the heavens bringing medical supplies and hope to the wounded… All six “L-birds” were on display Saturday… there was the Stinson L-1. [The event took place on Saturday the 17th. This was the Sunday edition. On the following Monday, the infamous “Black Monday” stock market crash occurred.]


N1ZS (s/n 41-18915) was registered in April 1992 (until 1995) to Dave Smith of San Antonio, Texas.





Karl S. Johnstone of Anchorage, Alaska, registered N1ZS on June 26, 1998 (until 2002).
“The Alaska Aviation Museum purchased 41-18915 from Alaska Judge Karl Johnstone in 2001” (per museum facebook). “The aircraft was donated to the Museum by Karl S. Johnstone in 2002” (per museum website). “It is the sole survivor of approximately 400 L-1s manufactured during WWII” (per museum website). Alaska Aviation Heritage Museum in Anchorage-Lake Hood, Alaska, registered the aircraft on January 29, 2003.


A second restoration of 41-18915 began in 2015, and was completed in summer 2016. The Alaska Aviation Museum opened the exhibit of its newly restored Stinson L-1 Vigilant on September 21, 2016.


To request a PDF copy of the magazine articles mentioned here, please visit Alamo Liaison Squadron at als-cannonfield.com.