Pitcairn Pa Engine Wright Rs E

pilot's seat was adjustable fore and aft. The copilot's seat was not adjustable, but had provision for bolting down to the structure at varying positions relative to the controls. The rear seat was forty-one and one-half inches wide. All the space Ln the fuselage wall, under the floor and on top of the cabin was packed with "Dry Zero" blanketing, the most efficient soundproofing and heat insulating material known in its day. Ventilators provided a continuous circulation of air, if desired, eliminating the need for opening the windows.

The instrument panel was finished to match the upholstery theme. The instrument complement included: altimeter, compass, air speed indicator, bank and turn, rate of climb, engine tachometer, electric rotor tachometer, electric fuel quantity gauge, oil pressure gauge, fuel pressure gauge, oil temperature and cylinder temperature, a clock and the company announced "an oil measuring rod accessible in flight." All the instruments could be serviced or replaced through a removable panel in the cowling ahead of the windshield and above the instruments. The control handles for the rotor clutch, rotor brake and parking brake, etc., were located in the instrument panel at its lower edge.

The control wheel and yoke were of the throw-over type so that the control could be passed to the copilot at will. The copilot's rudder pedals were folded back onto the floor and latched down with spring catches when they were not in use. All control cables were brought close together at the fuselage centerline and directed aft of the aircraft through a tunnel under the floor. Access was provided at most any point for servicing or replacement through screwed-down panels. The cables were not connected directly to the control surfaces which they control, rather they were connected to torque tubes within the fuselage which were in turn connected to the rudders or elevators.

The wing was of cantilever design and made in three basic panels. The centersection was approximately ten feet in span. Its wing chord was parallel, but the thickness tapered from the fuselage outward toward the outer panel attachment. The construction of the centersection was welded steel tubing. Two built-up welded steel tube trusses formed the front and rear spars. These were heat treated after welding. The drag braces were steel tubes which were welded into sockets made from larger size tubes which had been welded to the spar caps during the spar manufacture. The drag bracing was not heat treated.

The detachable outer panels were built up on a single wooden box spar carrying the aileron on its rear face. The inboard end was attached to the rear spar of the centersection with two bolts.

A system of ribs and drag braces formed the rest of the wing pane! which was entirely covered with spruce veneer. Doped balloon fabric then covered the entire wing, A fine, smooth finish was made on the doped surface. A single bolt attached the forward part of the wing to the

Windmill Hinge System

PA-19 cabin head-on view.

centersection front spar. Large ailerons with what Pitcairn describes as a "specially shaped leading edge ahead of the hinge line" provided lateral control. This was, of course, similar to the Frieze-type surfaces now in general use but were new and novel at that time. These would provide, Pitcairn goes on, "powerful control at low speeds without being overly-sensitive at high speeds."

An independent tripod landing gear was attached to each side of the wing centersection providing a wheel tread of 12 feet. All attachments to the centersection were fixed. The wheel axles were attached to the oleo pistons which were cantilever and gave a nine-inch travel to absorb landing shocks. Tires were 9.5x12 "sem i-balloon." A constant camber of the wheels was possible throughout the entire nine-inch travel. A smaller oleo strut with a full-swiv-eling wheel was attached to the rear of the fuselage.

The tail surface group was indeed unique and simple. The main member was a one-piece horizontal stabilizer assembly which was placed across the top of the upper longerons and bolted down. Construction was a wood frame with fabric covering. The elevator too was a single piece; this, however, of welded steel tubing with fabric cover. This was attached to the rear of the stabilizer through cast aluminum bearing blocks which were split to permit insertion of the elevator spar tube. Excess wear was taken out by filing or planing the mating faces of these blocks.

The vertical stabilizers were of welded steel tube construction, fabric covered. These were attached to the horizontal stabilizer at the leading edge and the front spar. The rudders, too, were of welded steel tubes attached to the rear of the vertical stabilizer both above and below the horizontal stabilizer. This particular tail configuration was chosen to offer the lowest profile, therefore offering good rotor clearance and to permit the vertical surfaces to operate in undisturbed air flow, clear of the fuselage.

The engine installed was a Wright R-975 E2 delivering 420 hp at 2150 rpm. Consideration was given to modifying the fuselage and/or the engine mount to accommodate the Pratt and Whitney Wasp "Junior," but no PA-19 was built with the P& W. An electric starter operated by a switch was similar to the automobiles of the day. The battery was installed in the fuselage aft of the cabin and was accessible through an outside door. Either hot or cold air could be diverted over the oil cooler as desired. Fuel was carried below the cabin floor in two tanks totaling 90 gallons. The front tank employed the familiar "stand pipe" arrangement, reserving a six-gallon emergency supply. The propeller installed was a ground-adjustable Hamilton Standard, although the literature promised that a controllable pitch propeller could be installed and the cruising speed would be improved by seven miles an hour.

The rotor blades were built in the same manner as the blades for the PC A-2 series; in fact, the blade attachments were interchangeable. The

3/4 front view of PA-19 (Pitcairn Photo)
Pitcairn Pa34

Right side of Pitcairn PA-Í9 cabin autogiro.

(Pitcairn Photo)

Right side of Pitcairn PA-Í9 cabin autogiro.

(Pitcairn Photo)

Pitcairn Cabin Autogiro

(Pitcairn Photo)

Left side view of Pitcairn PA-19 420 Hp, 5 place cabin autogiro.

Although he reached the gretitestaltitude ever attained by numinhis stratosphere; more than 10 miles above theearth Prof. August Piccard today had his first airplane ride, in a cabin model auiogiro, flown by fames C. Ray, from the Washington Hoover Airport.

(Underwood Photo)

Although he reached the gretitestaltitude ever attained by numinhis stratosphere; more than 10 miles above theearth Prof. August Piccard today had his first airplane ride, in a cabin model auiogiro, flown by fames C. Ray, from the Washington Hoover Airport.

(Underwood Photo)

blade chord and the airfoil were also identical. The PA-19 blades were merely longer by approximately one and one half feet thaii the PCA-2. In the assembly of the rotor system the same familiar droop and interblade cables were evident.

The entire aircraft with the exception of the areas normally cowled with metal was fabric covered. The finish was hand rubbed to a mirror-like gloss, providing a smooth, easy-to-care-for surface. No standard paint scheme was offered.

For the first time in autogiros a complete electrical system was available as standard. It consisted of an engine-driven generator, electric starter, position lights and cabin lights, and landing lights. Bonding and shielding for radio were optional items.

Four were complete; two found their way to England. The PA-19 was indeed a beautiful aircraft.

In Volume 6 of "U.S. Civil Aircraft" the author, JoeJuptner offers a fine tribute to the Pitcairn PA-19 Autogiro: "With such credentials the Pitcairn PA -19 took its place on the market of 1933; based on its ability and its outstanding utility the PA-19 should have found instant favor, but being confronted with the depths of a national depression was more than a craft of this type could bargain for. There was a token in terest, of sorts, but financial difficulty at the Pitcairn plant finally halted its production and further development. Actually, the cabin-type PA-19 was an aircraft too far ahead of its time."

Specification and performance were reported as follows:

Gross weight Empty weight Useful load

4035 lbs. 2675 lbs. 1360 lbs

These figures are from a factory brochure and again do not agree with the CAA Approved Data.

Cruising speed "over 100 mph"

add 7mph for controllable prop. High speed 125 mph

Landing speed 0 mph

Min descent speed at 27 mph 16 ft./sec. Takeoff distance, no wind 270 ft.


Wright R-975E-2 420 hp 90 gals. 8 gals. 3



No. pass. Baggage Standard weight

The front seals of the Pitcairn PA-19. The control column is a Waco cabin control unit.

(Pitcairn Photo)

Interior of Pitcairn PA-19 cabin autogiro.

(Pitcairn Photo)

Spec basis Approved Type Certificate

No. 509

Serial Nos. H-84 and up mfrd. prior to

9-30-39 eligible. Approval expired as of that date. (See NOTE 2)

Class 1 equipment: Battery 39 lbs,; Starter 30 lbs.; Generator 13 lbs.; Heater 5 lbs.; Propeller-adj. metal.

Class 111 equipment: Landing lights 15 lbs.; Flares (three 1 minute) 11 lbs.; Extra door 17

lbs.; Extra walk-way 15 lbs.; Elevator tab control 12 lbs,; Larger oil cooler 10 lbs.; Increase in weight of upholstery 8 lbs.; "Y" type control column, no change in weight; Propeller— controllable metal (Hm. Std. hub 2D30, blades 6101-6, low pitch setting 16°), net increase 60 lbs.

NOTE L Serial No. H-84 is same as production model except shock absorbers, fixed wing pylon structure, ailerons, and rear section of fuselage. Maximum standard weight 4097 lbs.

("Flight" Magazine Photo)

A PA-19 that found its way to England.

PA-19 making landing approach.

(Flight Magazine Photo)

Pitcairn Pa22

Pitcairn PA-22 in, perhaps, its original configuration.

(Pitcairn Photo)

Pitcairn PA-22 in, perhaps, its original configuration.

hi April of 1933 the Pitcaim organization began working on a new type of autogiro. This type promised to erase all the shortcomings of previous autogiros.

This autogiro incorporated "direct control"; a term which meant that the machine was controlled directly by the rotor, not depending on air speed for control sensitivity. As long as the rotor turned, the control was positive. Control was affected by tilting the rotor axis in the direction that control was wanted. Control response was equally good from the PA-22's high speed of 105 mph down to zero air speed. It was necessary to maintain only 12 mph in order to maintain altitude.

The PA-22 was a departure from normal four-bladed rotor to a three-bladed system in which the blades could be folded back over the fuselage for more convenient storage.

The real success of the machine must be credited to a British seven-cylinder radial 90 hp Pobjoy "Niagra" engine. This engine was geared .47 to 1 and delivered its power at 3500 rpm guaranteeing 84 hp at 3200 rpm. This permitted use of a large-diameter propeller for quick acceleration. Although designed as a two-placed side-by-side machine. Big Jim Ray, Pitcairn's

(Pitcairn Photo)

chief test pilot, took more than half its cabin space.

The control stick hung from the center of the roof and had to be pushed forward on the ground into a stick lock when the rotor rpm slowed below a speed that kept it gyroscopicatly stable. On run up for takeoff it was kept locked until enough rpm was attained to keep it from tumbling like a run down top, chopping at the fuselage. Another new feature was introduced with the PA-22 was "jump takeoff."

Prior to takeoff the rotor could be run up to about 150% of normal RPM with the blades held in a no-lift position. By releasing a clutch mechanism the pilot could simultaneously transfer full power from the rotor to the tractor propeller with the blades assuming flight pitch of about three degrees. The energy stored in the over-reved rotor was translated into lift and the Autogiro took off vertically. As the rotor RPM died off to normal the propeller pulled the craft into a normal climbing attitude. When the meteorological conditions were right a vertical jump to eight to ten feet was not unusual.

A normal takeoff could be made by running the rotor up to nearly cruising speed than disengaging the engine from the rotor, opening the r\

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