First engine chosen for the Aero Commander prototype, the Lycoming Model 0-435 190 H.P. For his book Stars and Commanders, Dave Duntz conducted years of research, including Ted Smith’s unpublished memoir. The memoir was published in chapter 7 of Duntz’s book, and will be presented here in three parts. This is the first installment. You can purchase Duntz’s book at www.starsandcommanders.com.
Now I was on my own and for a while the past ten years with Douglas and the success of the A-20 program was foremost in my mind. Subconsciously, my mind was thinking of this new era of aircraft and soon I was actively engaged in the new concept.
There were many unknowns. There were no aircraft in existence that could be called a true business aircraft. So, it was imperative that this new concept be different in design configuration. It must be of all metal semi-monocoque structure; it must be aerodynamically clean if it was to have better performance than the DC-3; it would not be necessary to carry more than five people – a pilot and seats for another four giving it a capacity of five; and designed so it could be convertible into a utility aircraft to carry small cargo and even converted further to a high-density version that could carry six or seven people on short trips within a 200 or 300 mile radius. In this period of time, which was many years before commuter aircraft came into existence, I could foresee the need for an aircraft that could be used for short haul service.
Before leaving Douglas in 1945, I visualized not only the need for an aircraft to be used as a business tool, but projecting this vision even farther into the future, I could see that air transportation would grow and continue to grow. Already Douglas had the DC-4, called the C-54 during the war, a larger passenger aircraft. They had flown prior to the war the B-19, at that time the largest aircraft in the world. So, with dreams and a projected vision one could readily extend the future of air travel through the coming years and realize intently that air transportation, in time, would become a fast growing and intensive industry.
It was only natural to assume with some confidence; a small twin-engine high-performance aircraft would someday be in demand in business. A tool for business that would equal or surpass the DC-3 in performance and would permit even small companies or individuals to have equipment that would not require hiring a pilot. Many of this type of company, in a majority of the cases, had a member of their management team who would do the piloting.
In a short period of time I had generated in my mind the basic configuration of this, the first true business aircraft in the world. Before leaving Douglas, I had taken time to sketch out several different concepts of an aircraft that would meet the requirement of this new business aircraft.
I believed that a high wing configuration would provide many desirable features. The wing loading should be reasonable so as to keep stall speeds down and permit the aircraft to operate in and out of short unimproved fields. In 1945 there were very few paved runway airports throughout the United States. Most of the small fields were grass or dirt strips and some were oil and gravel, but in most cases the larger municipal airports were paved.
Performance must be high—200 M.P.H. with two engines – and for safety, good performance on one engine. Comfort and visibility must be favorable for the pilot station and for the passengers. The airplane must have excellent and safe handling characteristics, good stability and controllability, one engine out characteristics must be favorable with no dangerous characteristics with the sudden loss of power on either side. Stall characteristics must be docile when operating with full power on two engines or one. Trim changes between power on and power off must be negligible both with the gear and flaps down or up. In all, it must be a modern up-to-date design with much thought given to producibility yet with imagination. It must, of necessity, be capable of growth in volume and in power. In good aircraft design, one must project or design not only for today, but for tomorrow as well.
Finally, after much study, sketches were made, aerodynamic data prepared, the final basic configuration was established and was ready for detail layout and detail engineering. This final configuration, as indicated on the three-view and in the specifications, turned out to be a high wing full cantilever monoplane of 3800 pounds gross weight and would carry five people with a potential for six or seven in a growth version. The pilot station was located ahead of the wing to provide excellent visibility in all directions and the passenger station was under the leading edge of the wing, also giving good and unobstructed visibility for the passengers.
Aerodynamically, the aircraft was clean and aesthetically good looking. Cruise speed at 70% power was predicted to be 180 M.P.H. with two Lycoming 190 H.P. six-cylinder engines. The wing had an area of 244 square feet; a gross weight of 3800 pounds, with stall speed estimated at 55 M.P.H.; minimum control speed with an engine out, 70 M.P.H. and a high speed of 190 M.P.H. at sea level with the 190 H.P. engines and over 210 M.P.H. with 250 H.P. engines.
The Lycoming Model 0-435 190 H.P. direct drive engine for the prototype was chosen for two reasons. It was of the desired power and had a good history during the war in the Stinson liaison airplane, the L-5.
The engine installation was designed into a cutout in the wing leading edge set far back against the front spar that was located at the 35% chord line of the wing.
Plan form of the wing had a straight leading edge and a swept forward trailing edge which kept the Mean Aerodynamic Chord (M.A.C.) forward for Center of Gravity (C.G.) purposes since the pilot station was far forward and without the engines being installed deep in the wing the aircraft would be out of C.G. range. The wing was a full cantilever design. All surfaces were aerodynamically, as well as mass, balanced and the stabilizer and vertical fin were also full cantilever design.
Shortly after the configuration had been established, I had attracted the attention of some of my people who were still at Douglas, including Pete Leaman who was now back at his little Culver City Airport. With the war over, almost overnight Culver City Airport became a very busy little airport. Several flight schools were opened at the airport and many G.I.’s received their flight training there under the G.I. Bill. Across the U.S.A. many thousands more were getting their flight training and pilot’s licenses were being issued by the thousands.
Pete Leaman had built an additional hangar on the airport and, since his interest was very high in the new project, he let me have the rear portion of hangar No. 1 for the development of the new aircraft yet unnamed.
Our entire group worked together on weekends to wall off the rear section of the hangar about twenty feet deep and about 65 feet across. Then the west side was enclosed for about thirty feet for the engineering room and office space.
We walled the area off into four sections—the shop area, an engineering room and in the extreme rear portion on the west side, one office and a reception room. We had one of our friends at Douglas work up the color schemes and design for the office. As it turned out it was simple, functional and aesthetically good looking. The office and reception room were done in pale blue and chocolate brown with the office having indirect lighting. The engineering room was painted in a light cream color, florescent lighted as was the shop area. However, the entire rear wall of the shop area was window area so in daytime hours no additional light was needed.
The engineering room was equipped with large drafting tables, either with ones we made or others that were purchased from surplus stock. After the war was over the government put out for sale much in the way of surplus stock—from the aircraft factories came tons of raw materials of all types: hydraulic cylinders, electric motors, pumps. Complete aircraft of all types from trainers to bombers. The A-20s came on the surplus market for $3700.00 each, the A-26 for $2000.00 – $2500.00, all brand new; Stearman, N-3N, Ryan, Waco, and other primary trainers went for $500.00 to $1000.00, basic trainers like the Vultee BT-13 for under $1000.00, most of them with new engines.
Tons of AN hardware became available for pennies each or so much a pound. Most of the materials to build the prototype Aero Commander came from surplus stocks.
We furnished the main office with a nice mahogany desk and chair, the secretarial office with desk, chair and typewriter, engineering with a Monroe Calculator that was purchased out of surplus stock from Hughes Aircraft.
Regular working hours were assigned those on the part time evening shift from 7:00 P.M. until 10:00 P.M. Everyone signed in and out so as to keep an accurate record of time expended in engineering and in the shop. Two people were on full time in the shop and as for myself I put in full time seven days a week without pay, subsisting on my savings accumulated during my years with Douglas together with my collection of War Bonds. We had a total crew of over twenty-five people pretty evenly divided between engineering and the shop.
