In the late 1950s, the U.S. Army’s inventory of the versatile L-23/U-8 Seminole series of light military transports ended with introduction of the L-23F – the versatile Beechcraft that set a new standard for fixed-wing Army aviation.
Thirteen years after the end of the bloodiest conflict on earth known as World War II, Americans were riding the crest of a major postwar economic wave that put a car in every garage and Dwight D. Eisenhower in the Oval Office. It was a time like no other. Consider just a few of the distant memories from that generation: Detroit’s GM, Ford and Chrysler went wild with tailfins, loads of chrome and gas-guzzling V-8 power. Drive-in theaters dotted the landscape, Wonder® Bread was in every kid’s lunchbox, Elvis was swinging his hips (but not on national TV!); nuclear fallout shelters were all the rage, pretty girls on roller skates served food to cool guys in “hot rods,” and color television was the technological marvel of the day.
In addition, the “Atomic Age” ushered in by the bombing of Hiroshima and Nagasaki in 1945 had slowly given way to the “Space Age,” with the United States and the Soviet Union vying to put elementary satellites into earth orbit while quietly racing to see who would be first to successfully launch a man into outer space.
It was also an uncertain time when the Cold War between the two nuclear superpowers was heating up and would eventually come to a high-stakes stand-off in Cuba in 1962 that threatened to plunge humanity into a global nuclear holocaust.
In the world of commercial aviation, however, the late 1950s saw the “Jet Age” mature with introduction of jet-powered airliners such as the British Comet and the Boeing 707. The market for small, piston-powered aircraft was enjoying strong growth and production lines were humming at Cessna Aircraft Company, Piper Aircraft Corporation and Beech Aircraft Corporation. Beech, in particular, was strengthening its grasp on the business aviation segment that had begun in 1932 with the bullish Model 17R1, evolved into the affordable and efficient Model 17 Staggerwing during the mid-1930s and hit its stride after the war with strong sales of the twin-engine Model 18 Twin Beech.
The U.S. military had long been an operator of Beechcraft airplanes and the company’s successful Model 50 Twin Bonanza had donned the uniform of the U.S. Army in 1951 with introduction of the L-23 Seminole. The light transport proved to be a rugged, versatile addition to the Army’s fixed-wing inventory, and the L-32A was soon followed by a series of upgraded and modified aircraft over the next seven years culminating in the L-23D of 1957.1
Although the Army brass were more than pleased with the overall L-23 design, by 1958 it needed a larger airframe to cope with evolving mission requirements that included increased VIP transport, rapid troop deployment and myriad liaison duties. What the next generation Seminole needed, according to the Army, was more interior volume and horsepower, and in 1958 the Army sat down with Beech engineers to lay out the basic requirements for a follow-on design to the L-23.
Fortunately for the Army, the solution was just beginning to roll down the Beechcraft production line – the Model 65 Queen Air. First flown in August 1958, the Model 65 differed significantly from its Model 50-series predecessors because of its redesigned fuselage and that included a cabin that had been completely regenerated in terms of length, width and height. Those modifications gave the new Beechcraft the type of true multi-mission capability the Army needed.
For example, in its high-density cabin configuration, the airplane could deploy up to seven combat-ready soldiers and their gear. By removing the seats, up to 1,350 pounds of cargo could be loaded, and the airplane lent itself well to further modifications such as the RL-23F that featured battlefield surveillance radar systems to collect combat intelligence information.
As part of the fuselage redesign, three large windows were added to the cabin for increased visibility with a smaller, fourth window in the aft cabin section. In 1959 when Beech Aircraft began delivering the Queen Air to customers, the Army acquired three airplanes designated as the L-23F.
From the Army’s viewpoint, the latest generation Seminole was a heavy-piston, twin-engine airplane with a maximum gross weight of 7,368 pounds (increased later to 7,700 pounds) with a wingspan of 45 feet, 10.5 inches. The airplane was powered by six cylinder Lycoming fuel-injected, geared, supercharged, opposed piston engines each rated at 340 hp (Lycoming IGSO-480 -A1A6, -A1B6 or -A1E6).
Maximum cruising speed was 214 mph and the L-23F could climb to a maximum service ceiling of 27,000 feet and had a range of 1,445 statute miles. The engine’s fuel injection system was designed and built by Bendix and featured automatic mixture control to reduce pilot workload and improve engine efficiency (a manual mixture control system was installed in case the automatic system failed).
From 1960 until production was terminated in 1963, Beech Aircraft records indicate that the company delivered 71 examples of the L-23F to the Army, but other records indicate 76 airplanes were built.2 The fleet of sturdy Beechcrafts served the Army well and a number were still in service with National Guard units as late as 1986. The military designation changed in 1962 from L-23F to U-8F.
As mission demands continued to evolve over the years and performance improvements became available, in 1984 the Army’s National Guard Bureau upgraded the engine installations in a majority of the L-23F/U-8F aircraft to eight-cylinder Lycoming fuel injected, opposed engines fitted with three-blade Hartzell propellers (the modification also included installation of new engine mounts). These changes were part of an FAA-approved, major modification to the original Beechcraft design, and was developed by Excalibur Aviation Company in San Antonio, Texas.
As the decade of the 1950s faded into history, aviation propulsion technology had progressed to the point that turbine power was coming of age for business aircraft such as the Queen Air. The Beech Aircraft Corporation was among the first to take the bold step of installing a turboprop engine in a modified Model 65 airframe, thereby creating the legendary King Air. But that is another chapter in the Beechcraft story. A
Endnotes:
Phillips, Edward H.; “Beechcraft—Pursuit of Perfection;” 1992, Flying Books
Harding, Stephen; “U.S. Army Aircraft since 1947;” 1990, Airlife Publishing, Ltd.