The PA-18 and PAA-1 (PA-20) looked very much alike. It was difficult in fact, unless some¬one was very familiar with each, to recognize the differences. A note to Aviation from Ed Rice, the Director of Public Information of the Pitcairn organization, says the PA-20 was built as a “companion model” to the PA-18. A decision was made to discontinue manufacture of the PA-20 about April 14, 1933 because of the sim-ilarity to the PA-18.

Construction of the fuselage was the same as all preceding Pitcairn Autogiros. An assortment of steel tube diameters and wall thicknesses were gas welded together. The sides and bottom of the fuselage were rounded out with wood fairing strips. The tail group was nearly identical to the PAA-1. The only noticeable difference was the shape of the auxiliary vertical fins. The wing was identical in construction de¬tails to the PAA-1, the span was decreased and the chord increased. The ailerons stopped short on the fuselage end to permit the walkway to extend to the trailing edge. The main landing gear was a scaled-down PCA-2 landing gear. The tail gear was a small wheel with a rubber chord shock absorber. A Kinner R-5, 160 hp engine turned a fixed-pitch Curtiss-Reed metal propeller eight feet, four inches in diameter. A ground adjustable propeller was optional at an increase of five pounds. A “coupe top” was also optional. The rotor was identical to the PAA-1 (PA-20, PA-24) except that it was 40 feet in diameter. The rotor pylon was simplified to one fore and one aft member with wire bracing from the top of the pylon to the upper longerons. They were priced at $6,750 with flight instruction.

The fatal crash of a Pitcairn autogyro in Oct 1935 ended one of aviation’s longest safety records, when pilot Robert Swenson tried to stretch a glide over power lines after an engine failure.

Pitcairn PA-18 built about 1931 for the sportsman and private user (ATC 478). About 19 of these were built and sold seven or eight of these were recalled during WWII and rebuilt as PA-39. All but one of them were lost when their transport was sunk.

Approved Type Certificate No. 478 applied to serial numbers from G-62 up to those manufactured prior to 30 September 1939, when the Approval expired.

Gallery

Year: 1931
Engine: Kinner R-5, 160 hp
Prop: fixed pitch 2 blade
Rotor dia: 40 ft
No of blades: 4
Span: 21 ft 3 in
Length: 19 ft 5 in
Gross wt: 1900 lbs
Empty wt: 1310 lb
Fuel cap: 30 USG
Max speed: 95 mph
Cruise: 83 mph
Range: 225 mi
Ceiling: 12,000 ft
Seats: 2

The 1931 Pitcairn-Cierva PCA-3 (ATC 446) was a PCA-2 with a 300hp P&W Wasp Jr engine. The one built, NC11612 c/n E-45 was priced at $15,000 (it finally sold for $5,000).

Year: 1931
Engine: P&W R-985, 300 hp
Rotor dia: 48 ft
No of blades: 4
Gross wt: 3063 lb
Empty wt: 2098 lb
Useful load: 942 lb
Max speed: 120 mph
Cruise: 100mph
Range: 300 mi
Ceiling: 15,000′
Seats: 3

1928 found Cierva giving demonstrations of the O-19 and selling the manufacturing rights to representatives from around the world. The American rights were purchased by Harold Pitcairn who made a few design changes but retained the basic design principles and features found on Cierva’s machine.

Pitcairn used a more modern fuselage with better aerodynamic qualities for his PCA-2 gyroplane, and offered two engines for use in the aircraft. Both were radial aircraft engines mounted in the usual tractor configuration: the first produced 300 horsepower, the second, 420hp. Pitcarin also utilized a four-bladed rotor system with Civerva’s flapping hinge. It innovated with a clutched gearbox that briefly transmitted power to prerotate the rotor to greatly shorten the takeoff run.

Pitcairn produced and sold 24 of his PCA-2 gyroplanes over the next few years at $15,000, including NC26/NC2624, NR784W, NC799W, NC10761, NC10768, NC10780/19781, NC10785/10791, NC11608/11611, and NC11613. They showed the versatility and practicality they had been designed for by carrying the mail over a federally contracted route, being used to reach the scene of the news and for aerial photography by the “Detroit News” daily newspaper, and by setting new world records. Amelia Earhart flew a PCA-2 to the record altitude of 18,415 feet over Willow Grove, Pennsylvania on April 8, 1931. On 25 September 1932 Lewis Yancey reached 21,500 ft.

The first “non-conventional” aircraft to earn government approval; ATC 410.

Three were used by Earhart for a transcontinental cross-country flight in 1931, including NR10761 and NC10780.

Amelia had two different accidents; the first was at Abilene TX on 12 June 1931. A second PCA-2 was flown to her to continue her transcontinental journey. On 12 September 1931, she dropped it in from 20 feet at Detroit. She was quoted in the New York Times as saying, “Nothing to it, it was all my fault, and I’m not injured at all. I just didn’t level off soon enough.” Then, “Within a few hours after the crash, Mrs Putnam set out for Saginaw in another Autogiro to fulfill an exhibition flying engagement.”

Prototype
Year: 1931
Seats: 3
Engine: Wright R-760-4, 240 hp
Gross wt: 3000 lb
Rotor dia: 48 ft
No of blades: 4

Year: 1931
Engine: Wright R-975/E, 300 hp
Rotor dia: 45 ft
No of blades: 4
Wingspan: 30’0″
Length: 23’1″
Gross wt: 3000 lb
Empty wt: 2025 lb
Max speed: 118 mph
Cruise: 98 mph
Range: 290 mi
Seats: 3

Pitcairn had refined Autogiro development, first learning from the C8W (which was presented to the Smithsonian on July 22, 1931), then with a series of developmental aircraft, the PCA-I, 1A and lB. (The PCA-1A is currently exhibited at the American Helicopter Museum & Education Center at the Brandywine Airport, West Chester, PA on loan from the Smithsonian).

The three Pitcairn-Cierva built, NX94N/96N, were redesign of Cierva C-8 using PA-5 Sport Mailwing fuselage. The first commercial autogyro in USA.

Year: 1930
Engine: Wright R-760-4, 240 hp
Gross wt: 2750 lb
Rotor dia: 43 ft
No of blades: 4
Span: 32 ft 0 in
Length: 23 ft 0 in
Seats: 3