Entering into the market in late 1954, the arrival of the Cessna 310 marked the first twin-engined aircraft that Cessna put into production after World War II.
The four-to-six-seat low-wing twin first flew on 3rd January 1953 and included innovative features such as engine exhaust thrust augmenter tubes, through which the exhaust gases from the aircraft’s reciprocating engine were directed to provide additional thrust. The 310 was quickly picked up as a charter aircraft for numerous post World War II air taxi firms.
The Cessna 310 held considerable advantages over its rivals like the Piper PA-23 in terms of speed, economical operating costs and the availability of aftermarket modifications such as the Robertson STOL kits which made it popular for bush flying. The 310 was able to use short runways while carrying a useful load of 910 kg or more, which made it an incredibly versatile aircraft.
Perhaps most famously, the Cessna 310 was featured on Sky King, an American radio and television series. Trading a horse for an aircraft, the Western-based series had the lead character, Schuyler “Sky” King capture criminals and spies using his Cessna 310, dubbed the “Songbird”. The first Songbird was a Cessna T-50 Bobcat, but it’s the 310 that is best remembered, featuring in later episodes up until the series’ end.
In 1957, the United States Air Force (USAF) chose the Cessna 310 to replace its fleet of ageing Beech C-45s for service as light utility aircraft for transport roles. The USAF purchased 160 310As with the allocated designation of L-27A. It quickly garnered the nickname the ‘Blue Canoe’ after its distinctive blue and white colour scheme. And even though both the US Army and Navy made use of the aircraft under different livery, the nickname remained.
The official designation of the L-274A was changed to U-3A in 1962. An additional 36 upgraded 310D designated L-27B (later U-3B) were delivered over 1960 and 1961 and featured more powerful 260 hp (194 kW) engines and extra cabin windows and elongated nose and swept vertical fin. The 310D marked the first 310 to feature the swept vertical tail.
The U-3 served as a tester for new avionics equipment and conducted navigational route surveys and certification checks of navigation aids. During the Vietnam War, USAF U?3s supported the Farm Gate aerial reconnaissance programme by transporting film, photographs and intelligence reports to troops on the ground.
During the late 1960s, the 100th Strategic Reconnaissance Wing at Davis-Monthan AFB in Tucson, Arizona, also used the 310 as a chase plane and companion trainer for their Lockheed U?2 high?altitude reconnaissance aircraft. The U-2 and U-3 formation became known as the “U?2 and Me?Too.”
A development of the 310F was the turbocharged 320 Skyknight, with TSIO-470-B engines and a fourth cabin side-window. The Skyknight was in production between 1961 and 1969 (the 320D, E and F were named Executive Skyknight), when it was replaced by the similar Turbo 310.
The 310G was introduced in 1962 and featured the canted wingtip fuel tanks found on most of the Cessna twin-engined product line, marketed as ‘stabila-tip’ tanks by Cessna because they were designed to maximise stability in flight. A single side window replaced the rear two window configuration on the 310K of 1965, with optional three-blade propellers being introduced as well. Subsequent developments included the 310Q and the turbocharged T310Q which featured a redesigned rear cabin and a skylight window.
The last production models of the Cessna 310 series were the 310R and T310R. The 1975 model year 310R had 285 hp (213 kW) Continental IO-520-M or IO-520-MB engines; three-blade propellers as standard, a lengthened nose containing a baggage compartment; and a 2,500 kg maximum take-off weight. The T310R also featured a turbocharged Continental TSIO-520-B or TSIO-520-BB engine.
Over the years there were several modifications made available to the 310 to improve performance. Aircraft engineer Jack Riley produced several variants for the aircraft line including the Riley Rocket 310 and the Riley Turbostream 310. Mr Riley replaced the standard Continental 310 hp (230 kW) engines with 350 hp (261 kW) Lycoming TIO-540 engines. These turbocharged intercooled engines were installed with three-blade Hartzell propellers in a counter-rotating configuration to increase performance and safety. This resulted in a cruising speed of 480 km/h at 18,000 feet.
On the used market, a 1979 Cessna 310R will cost approximately $218,000, an 1873 Cessna T130Q costs around $122,000 and a 1969 Cessna 320P costs approximately $88,000.