The Twin Commander has a long and distinguished history of being a comfortable, safe, and dependable aircraft. At the end of WWII, a project engineer named Ted Smith noticed a significant gap in the aircraft industry. He found that business travelers and individuals who traveled to destinations that weren’t frequently serviced by commercial carriers were lacking in travel options—they needed a private aircraft that could get them to their location.
Coming to that conclusion, Ted Smith assembled a team of 14 engineers to design what became the very first Twin Commander. The first prototype took its first flight on April 23, 1948, and was certified in June of 1950. The Twin Commander was well received by the market because of its high level of capabilities. To drive its performance benefits home even further, Aero Design and Engineering Co.—the company behind the Twin Commander—completed a flight from Oklahoma City to Washington DC with the aircraft loaded to its full gross weight, with one propeller removed from the plane. This record-breaking flight proved that the Twin Commander had incredible asymmetric control and responsiveness. From there, sales soared and continued until the production of Twin Commanders ended in 1986.
The Twin Commander is known for its fuel-efficiency, large cabin, and long range capabilities. Since the Twin Commander’s first production in the 1950s, there have been several iterations and model variants, each improving on the performance and adding features, design upgrades, and new power plants.
Twin Commander models can be divided into three categories: Early piston engine powered models, turbine powered models, and jetprop models, which are the most recent.
Piston Engine Models
Built in the 1950s, the first Twin Commander models were originally called Aero Commanders. They were powered by twin Lycoming piston engines and have 500 series model designations.
Over 1,000 500 series Twin Commanders are flying today.
The Model 500S, also referred to as the model 520 or the Shrike Commander, is the original Twin Commander. It’s shorter in length compared to later models and comfortably carries seven passengers and 350 lbs. of luggage.
The 560 and 560A models replaced the 500S and 520 models in 1954. This new iteration created a larger cabin by adding 10 inches to the overall length of the fuselage. The 560 series also included more powerful Lycoming piston engines that led to significant performance improvements. In fact, the 560 model was the first light twin engine aircraft that was considered safe enough by the US Air Force for use by the President.
The 680FL was introduced as the Grand Commander in May of 1963. Two sections were added to the plane—a 44-inch section forward of the front spar and a 30-inch section aft of the front spar. These two additions effectively added six feet to the length of the plane, bringing the overall length to over 42 feet.
At the time of its release, the Grand Commander offered leading cabin area space per occupant. It was with this model that the large under wing picture windows were released, which became a trademark of the Twin Commander.
In the 1960s, jet engines were becoming more and more popular with commercial airlines, which meant that the demand for them in the general aviation market also increased. In response, the first turbine powered Twin Commander, the 680T Turbo Commander, was designed and certified in 1964 and 1965. The 690A and 690B models followed the 680T and were the primary turboprop Twin Commander models.
The 690A was produced in 1973 and featured airframe changes that increased the center wing section by 30 inches, increased the rudder area, enlarged the dorsal fin, and lengthened the tail cone. These changes increased the gross weight to 9,600 lbs and increased the baggage capacity to 600lbs (the highest for Twin Commanders at the time).
It was with the 690A that a heated windshield was introduced, as well as increased cabin pressure differential, and standard de-icing equipment. All of these improvements changed the maximum ceiling rating from 25,000 feet to 31,000 feet.
There were many similarities between the 690A and 690B. The 690B first flew in 1976 and featured increased weight ratings, two engine options, and several modifications to the cabin interior.
In the late 1970s and early 1980s, the most advanced Twin Commanders were produced—the enhanced turbine powered jetprops.
With the model 840, the Twin Commanders wings were increased a further 30 inches and canted winglets were added to increase the overall wing area. Wet wings were added to increase the fuel capacity from 384 gallons to 482 gallons, which allowed the 840 to have a maximum range of 2,040 nautical miles. This shift made the 840 the first Twin Commander to break the 2,000 nautical mile range barrier.
The model 980 was identical to the 840, with the exception of the engine. In the 980, Honeywell TPE331-511k engines were used. This change decreased the time to climb to an altitude of 20,000 feet from 9.5 minutes on the 840 to 7.2 minutes on the 980.
The 900 model was released in 1981 and continued to iterate on the engine and capabilities advancements of the Twin Commander. Shaft horsepower increased to 748.3 per engine and the landing weight increased to 10,550 lbs.
The biggest shift with the model 900, however, was with the interior. The cabin interior was lengthened by three feet to give the 900 model one of the best cabin volume per passenger ratings at the time.
The first version of the 1000 (the 695A) was released in 1981 and was identical to the model 900 with the exception of the engine. This was the first Twin Commander to feature the TPE331-10 engines.
In 1984, a second version of the 1000 was released, the 695B, which also featured Dash 10 engines and raised the shaft horsepower output to 820 per engine. With the gradual performance improvements made to the Twin Commander over time, the Twin Commander 1000 model had a maximum cruising speed of 308 knots and a maximum range of 2,080 nautical miles on 482 gallons of fuel. The maximum ceiling rating also increased to 35,000 feet.
The model 1000 was the most advanced, and final, version of the Twin Commander to be produced.
Winner Aviation is a Factory Authorized Service Center for all Twin Commander aircraft
At Winner Aviation, we are a Factory Authorized Service Center for Twin Commanders. Our experienced and dedicated maintenance team is ready to walk you through your maintenance and inspection needs, and to walk you through an inspection schedule that could save you time and costs. Contact us today for more.