HISTORY

Aero was formed in Culver City, California in 1944 to design and manufacture a light twin-engine transport aircraft. Ted Smith, a former project engineer at Douglas Aircraft Company, assembled a team of 14 engineers to design what would be the Aero Commander. Preliminary design was completed in 1946. The first prototype took flight on April 23, 1948, and was certified by the Civil Aeronautics Administration (CAA) in June, 1950. Three men funded the company's early efforts: Philadelphia attorney George Pew and Oklahoma City brothers William and Rufus Travis Amis.

In September 1950 it became the "Aero Design and Engineering Company" of Oklahoma. Its facilities consisted of an aircraft hangar and 26,000 sq ft (2,400 m²) manufacturing facility located at what is now Wiley Post Airport (PWA) near Oklahoma City.

In 1950, when the developers were working to satisfy the Civil Aeronautics Authority (CAA) regulations for certification of the Model 500, they chose a novel method of demonstrating its single engine capabilities.  They removed one of the two-bladed propellers, secured it in the aft cabin, and flew from Bethany, Oklahoma to Washington, DC on one engine.  There they met with CAA personnel, then replaced the propeller, and returned to Oklahoma in the conventional manner.  The flight received nationwide coverage in the press. 

In August 1951, the first production Aero Commander, the piston-powered Model 520, rolled off the assembly line.

The company was acquired by Rockwell-Standard in 1958.  In 1967 Rockwell-Standard merged with North American Aviation and the merged company became known as North American Rockwell. The company changed its name again in 1973 to Rockwell International and named its aircraft division North American Aircraft Operations

The company developed a two-engine business jet, the 1121 Jet Commander with deliveries beginning in 1965.  However, following the merger with North American Aviation the manufacturing rights were sold to Israel Aircraft Industries (IAI) in 1968, who produced a modified version as the Westwind.

Following the sale of the Aero Commander Division to Gulfstream Aerospace in 1981, the final Twin Commander model 1000 was released, powered by Dash 10 engines.  In December 1985, Gulfstream Aerospace was acquired by Chrysler Corp. With a new focus on the business jet market, production of the Twin Commander ended in 1986.  No single engine Commanders were produced by Gulfstream. 

In 1988 Gulfstream sold the rights of the single engine Commanders to Randall Greene, who set up Commander Aircraft to provide support for existing aircraft.  In addition, the company produced about 200 new aircraft from 1992 to 2002.  Commander Aircraft was subsequently liquidated.  In 2005 the Commander Premier Aircraft Corporation (CPAC) was formed by over 50 owners of Commanders in order to provide spare parts support for their aircraft, and was based in Cape Girardeau, Missouri.  However, by May 2012 CPAC was in Chapter 7 bankruptcy.  In 2014, the assets of CPAC were purchased at auction and operations were moved to Norman, Oklahoma.  As of 2020, the company continues to operate as the Commander Aircraft Corporation. 

In 1989 Twin Commander rights were acquired by Precision Aerospace Corporation. With this acquisition, the company transformed from an aircraft manufacturer to an OEM parts, service and support provider. In 2003, the company was reincorporated as Twin Commander Aircraft, LLC, and then in 2005 acquired by James and Mark Matheson from Precision in a management buyout. In August of 2008, the Matheson’s sold the company to Firstmark Corp. of Richmond, Va., a company with a long history of supporting legacy aircraft. As of 2020, Firstmark Corp. continues to operate Twin Commander Aircraft LLC as an OEM parts and service provider.

Twin Engine Products

Models 500S and 520: The original Twin Commander. The prototype design was certified by the CAA, the predecessor organization to the FAA, in 1950. The first 500S rolled off the assembly line in August of 1951. The 500S was known as the Shrike Commander. Despite its shorter length compared to later models, the 500S could comfortably carry seven passengers and 350 lbs. of luggage. The plane had a maximum range of 693 nautical miles that was considered long for light aircraft of the time period. The unpressurized cabin and piston engines limited the 500S to a 15,000 ft. ceiling. A prototype of the 500S is the model that completed the historic single engine flight from Oklahoma City to Washington D.C. in May of 1951.

Models 560 and 560A: Replaced the 500S and 520 models in 1954. The success of the 500S and 520 models allowed engineers at the Aero Design & Engineering Co. to design a larger cabin into the 560A model by adding 10 inches to the overall length of the fuselage. In addition, the 560 series featured improved and more powerful Lycoming piston engines that led to significant performance improvements over the 500S and 520. The 560 series marked a significant milestone for the Twin Commander as well as the general aviation industry.  Later variants of the 560 featured more powerful engines, 32 inch winch tip extension, hydraulics modifications, redesigned landing gear, fuel injection engines and minor fuselage changes.

The military version of the Model 560 was originally designated as L-26, but was changed in 1962 to U-4 for the U. S. Air Force and U-9 for the U. S. Army.  Two aircraft were assigned to the White House and the L-26 / U-4 was used by President Dwight D. Eisenhower from 1956 to 1960 for short trips. It was the smallest Air Force One, and the first presidential aircraft to have only two engines. It was also the first presidential aircraft to carry the familiar blue and white paint scheme.

Model 680FL: Introduced in May of 1963 as the “Grand Commander”. This was the first Twin Commander model featuring the lengthened fuselage seen on later Turbine and JetProp powered models. 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. This added over six feet to the length of the plane, bringing overall length to over 42 feet. The Twin Commander offered leading cabin area space per occupant and the plane’s gross weight rating increased to 8,500 lbs.

Model 680V:  Introduced the large under wing picture windows that offered rear cabin occupants an unprecedented outward view from the plane. These windows would become a Twin Commander trademark in future years.

Model 680T:  The growing use of jet engines throughout the 1960’s by commercial airlines led to demand by the general aviation market for increased aircraft speed. This market demand increased in the late 1960’s with the introduction of small jet engines for use in jet powered business aircraft. In response to this demand for increased speed, the Company undertook design and certification work for the first turbine powered Twin Commanders during 1964 and 1965. The first turbine powered Twin Commander was the 680T called the “Turbo Commander” that used Garrett AiResearch TPE331 turbine engines. The increased power of the Garrett AiResearch engines allowed for a gross weight rating of just under 9,000 lbs., better flight performance characteristics and increased take off power. The high gross weight rating and additional power required certain configuration changes to the airframe that altered the flight characteristics of the plane. The 690A and 690B models that followed the 680T were the primary turboprop Twin Commander models.

Model 690A:  First produced in 1973, the 690A represented a significant advancement for turboprop Twin Commander aircraft. This model used the more powerful 251K variant of the AiResearch TPE331 power plant and Hartzell propellers. Airframe changes included an increase of 30 inches at the center wing section, increased rudder area, enlarged dorsal fin and longer tail cone. These changes allowed for a gross weight rating of 9,600 and baggage capacity of 600 lbs., the highest for a Twin Commander. Other changes such as the addition of a heated windshield, increased cabin pressure differential and standard de-icing equipment, changed the maximum ceiling rating from 25,000 feet to 31,000 feet.

Model 690B: First flew in 1976 and was similar to the 690A with increased weight ratings, two engine options and several modifications to the cabin interior including larger baggage space.

Model 840:  Major changes were made to the Twin Commander with the introduction of the model 840 in 1979. The wings were increased 30 inches and canted winglets were added to increase total wing area. The 254K variant of the AiResearch gas turbine TPE331 engines were used that generated 717.5 shaft horsepower each with new Dowty full feathering and reversible propellers. Wet wings were added outboard of the nacelles increasing fuel capacity from 384 to 482 gallons. The increased fuel capacity of the wet wings and fuel efficiency of the new engines allowed the 840 to have a maximum range of 2,040 nautical miles. It was the first Twin Commander to break the 2,000 nautical mile range barrier. Aircraft dry weight decreased by 507 lbs. over the 690B.

Model 980:  Same as the 840 except for the more powerful Honeywell TPE331-511k engines with 733 shaft horsepower. These engines 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.

Model 900:  Released in 1981 Model 900 featured continued advancement of the engines and capabilities of the plane. Shaft horsepower increased to 748.3 per engine while landing weight increased almost 1,000 lbs. over previous models to 10,550 lbs. The most important advancement of the model 900 was the interior layout. Without extending the overall length of the fuselage, the cabin interior was lengthened by three feet increasing total cabin volume to 278 square feet. This change gave the model 900 one of the best cabin volume per passenger ratings in its segment. The model 900 and model 1000 (below) were the only two models designed and released under Gulfstream ownership.

Model 1000:  The most advanced version of the Twin Commander. The first version of the 1000 (695A) was certified in April, 1981 and was the same aircraft as the model 900 except that it used Honeywell TPE331-511k engines, better known as Dash 10. In February, 1984 a second version of the model 1000 was released (695B) that used Dash 10 engines, raising shaft horsepower output to 820 per engine. This gave the aircraft a maximum cruising speed of 308 knots and maximum range of 2,080 nautical miles on 482 gallons of fuel. The maximum ceiling rating increased to 35,000 feet. Weight ratings also increased slightly over the model 900. Minor structural changes were made to the 1000 to accommodate the increased weight ratings and engine power.

Model 1121 Jet Commander: Twin jet engine midwing business aircraft introduced in 1963 with deliveries beginning in 1965.  After Aero Commander was acquired by North American Rockwell, the Jet Commander was sold to Israel Aircraft Industries (IAI) in 1968 thus leaving the North American Sabreliner as the sole business jet in the product line.  IAI made some modifications to the Jet Commander design and sold it as the IAI 1123 and 1124 Westwind.

Single Engine Products

Model 100:  Various models of which were known as the Darter Commander and Lark Commander was a high-wing, single engine monoplane of conventional design, equipped with fixed tricycle undercarriage.  The aircraft was originally designed by Volaircraft, first flying in 1960. The firm marketed the original three-seat version as the Volaire 1035 and a four-seat version with a more powerful engine as the Volaire 1050 before North American Rockwell purchased all rights to the design in 1965 for production by its Aero Commander division. Production of the Darter Commander version continued until 1969 and of the revised Lark Commander until 1971.

Model 112:  The Rockwell Commander 112 is a four-seat, single piston-engine monoplane of original design produced from 1972 to 1979.   Variations include the 112A, 112B, 112TC, and 112TCA. 

Model 114:  An improved version of the Model 112 that was produced from 1976  to 1979 by Rockwell international.  It was also produced as the Commander 114B and 114TC by the Commander Aircraft Company from 1992 to 2002. 

Model 200: Single-engine four-seat low-wing piston-engine civil utility aircraft with retractable tricycle undercarriage.  Design rights were purchased from Meyers Aircraft Company and sold to Interceptor Corporation in 1968 after only 77 Aero Commander 200's were completed. Retractable tricycle undercarriage.

Ag Commander A-9: (1950s) Single-engine one-seat low-wing aerial application aircraft. Horizontally opposed piston engine. Fixed tail wheel undercarriage. Design rights were purchased from CallAir Aircraft and was originally known as the CallAir A-9.

Ag Commander S-2 Thrush: (1956) Single-engine one-seat low-wing aerial application aircraft. Radial piston engine. Fixed tail wheel undercarriage.  Design rights were purchased from Ayres Aircraft and was originally known as as the Ayres Thrush (aka Snow S-2).  The Ag Commander brand was dropped in 1970.

Sources: Wikipedia and Twin Command LLC History