The Model 680FLP was the fourteenth Commander to be placed into production, the first 33 by the Aero Commander Division of Rockwell-Standard Corporation at Bethany (Wiley Post Airport) in Oklahoma City, Oklahoma. The next four were produced by the Aero Commander-Bethany Division of Rockwell-Standard Corporation, and the last was built by the Aero Commander Division of North American Rockwell Corporation.
The 38 examples were produced between December 1962 and September 1968, with serial numbers in the range 1261-1 through 1854-38.
Of these, the first one was initially certified in 1962 followed by 10 in 1964, 13 in 1965, nine in 1966, four in 1967, and the last one in 1968.
Later, however, serial number 1261-1 was converted to a Model 680FL and given serial number 1261-108; and 1473-3 was converted to a Model 680T and given serial number 1473-1.
Three examples have had the pressurization system removed and were then operated as 680FLs. Early factory documentation referred to this model as a 680FPL.
A factory document describes the Model 680FLP, under Wing Drawing 5170045, as “certified on October 8, 1964 per CAR 3, May 15, 1956, Amendments 3-3 and 3-4. The 680FLP is a pressurized version of the 680FL and is identical structurally and aerodynamically to the 8500-pound 680FL.”
The Model 680FLP was indeed certified on October 8, 1964 under Type Certificate 2A4. The first 33 examples had 340-hp Lycoming IGSO-540-B1A engines, while the remaining five were fitted with the -B1C engine variant. Both versions had the 87-inch diameter Hartzell HC-B3Z30-2B/9349-6.5 propeller.
Gross weight is 8,500 pounds, with cabin pressure differential of 3.2psi, giving a 15,636-foot cabin at an altitude of 27,500 feet, and a sea level cabin at 6,636 feet.
The beaded or corrugated control surfaces were used up to and including serial number 1527-24. From serial number 1599-25 on they became the smooth or flat-skin type.
The Model 680FLP can be visually identified by the dorsal scoop on top of the fuselage just aft of the wing trailing edge. Also, the pilot’s Direct Vision, or storm port, in the cockpit side window was suitably strengthened or deleted.
Thirteen 680FLPs subsequently were modified to Mr. RPM (Richard P. MacCoon) Turbo 800s, under STC SA2891WE. These had the 400-hp Lycoming IO-720-B1B(D) engines, modified with the installation of a Rajay turbocharger system under STC SE62WE, coupled with 80.625-inch-diameter Hartzell HC-A3VK-2A/V8433(N)(B)-4R propellers.
One strange anomaly is serial number 1527-24 680FLP, which was built between serial numbers 1515-23 and 1599-25. However, there was a telegram from the Aero Commander Division of Rockwell-Standard Corporation to the Canadian Department of Transport, clearly quoting the aircraft’s serial number as being “1527-29.” This serial number 680FLP has, therefore, been quoted—in error—on all subsequent paperwork, as evidenced by a check on the current FAA registry for N401MG.
Barry Collman’s lifelong interest in airplanes began when he was growing up in a house located underneath the downwind leg to busy Northolt aerodrome, an R.A.F. base near London-Heathrow airport. As a young teenager he discovered airplane “spotting”–hobbyists’ observation and logging of aircraft by make, model, and registration number. The hobby began to grow into a passion as Collman joined a club of like-minded spotters. At one point he purchased a copy of the January 1966 U.S. Civil Aircraft Register, and thumbing through it came upon the Aero Commander. He was hooked. Eventually he acquired every available FAA microfiche file on Commanders, and since 1995 has made annual pilgrimages to Oklahoma City to sift through FAA records. He now has a database with more than 96,100 records as well as a collection of negatives, slides, photographs, digital images, magazines, brochures, knick-knacks–and a very understanding wife. This series on Commander production history originally was written for the Twin Commander Flight Group, of which he is an enthusiastic member.