Pitcairn Mailwing

The Pitcairn Mailwings were developed to carry air mail for the United States Post Office Department. Of simple and robust construction, they had relatively benign flying characteristics.[1]

They were constructed using chrome-moly steel tube and square-section spruce spars with spruce and plywood built-up ribs. The fuselage was faired using wooden formers and covered with fabric. The tail sections were built up from steel tube and fabric-covered. The Pitcairn Mailwing had a ground-adjustable fin and in-flight adjustable tailplane.[1]

The undercarriage was of outrigger type with Oleo-Spring shock absorbers and disc brakes on the mainwheels. All versions looked very similar and changes were minor, with several fuselage extensions being the most obvious.[1]

The mail was carried in a fireproof metal-lined compartment forward of the pilot's cockpit. The Mailwings were flown extensively by the U.S. Air Mail service from 1927 until the end of dedicated Air-Mail routes.[1]

Pitcairn also built the same aircraft in sport versions for private use. These aircraft had the mail compartment removed, and a side-by-side two-seat cockpit was fitted.[1]

Pitcairn Mailwing PA-5, at the National Air and Space Museum

PA-7S Super Sport Mailwing

Data from: Aerofiles : Pitcairn[2]

• PA-5 - original production version of 1927 with Wright J-5-9 engine; ATC 18 (32 built)
  • PA-5 Mailwing - mail carrier version
  • PA-5 Sport Mailwing - sport version with seats for two passengers
• PA-6 - 1928 production version with Wright J-5-9 engine; ATC 2-22 (early), 92 (late) (53 built)
  • PA-6 Super Mailwing - mail carrier version
    • PA-6B Super Mailwing - (1 converted from PA-6)
  • PA-6 Sport Mailwing - sport version with seats for two passengers
• PA-7 - 1929 production version with Wright J-6 engine; ATC 196
  • PA-7A Sport Mailwing
  • PA-7M Super Mailwing - mail carrier version (12 built)
  • PA-7S Super Sport Mailwing (15 built)
• PA-8 - 1930 production version with Wright J-6 engine; ATC 364
  • PA-8M Super Mailwing - mail carrier version (6 built)

 United States

• United States Post Office Department
• Howard Hughes owned a PA-5 with a chrome plated engine.
• Felix du Pont owned a PA-5 with gold plated rocker covers.[3]
• Steve McQueen owned a PA-8

• PA-5 c/n 1 NC2895 on display at the Air and Space Museum, Washington, DC
• PA-5 c/n 9 NC3835 currently on display at the Shannon Air Museum, Fredericksburg, VA
• PA-6 c/n 48 NC548K currently on display at the Eagles Mere Air Museum, Laporte, PA
• PA-7S c/n 147 NC95W on display at the EAA Aviation Museum, Oshkosh, WI
• PA-7S c/n 151 NC13158
• PA-6 c/n 159 NC15307 on display at the Old Rhinebeck Aerodrome, Poughkeepsie, NY
• PA-8 c/n 164 NC10753
• PA-8 c/n 162 NC10751 on display at the Wings of Freedom Aviation Museum, Horsham, PA

Pitcairn PA-7 Sport Mailwing 3-view from Aero Digest April, 1930

Data from Jane's all the World's Aircraft 1931,[4] Aerofiles: Pitcairn[2]

General characteristics

• Crew: 1
• Capacity: mail compartment 40 cu ft (1.1 m³) / 550 lb (250 kg) payload
• Length: 23 ft 9 in (7.24 m)
• Upper wingspan: 33 ft (10 m)
• Lower wingspan: 30 ft (9.1 m)
• Height: 9 ft 6.5 in (2.908 m)
• Wing area: 243.5 sq ft (22.62 m²)
• Airfoil: Pitcairn No.1
• Empty weight: 1,820 lb (826 kg)
• Gross weight: 3,050 lb (1,383 kg)
• Fuel capacity: 60 US gal (50 imp gal; 230 L)
• Powerplant: 1 × Wright J-6 Whirlwind 9-cylinder air-cooled radial piston engine, 220 hp (160 kW)
• Propellers: 2-bladed Standard steel propeller

Performance

• Maximum speed: 150 mph (240 km/h, 130 kn)
• Landing speed: 57 mph (50 kn; 92 km/h)
• Cruise speed: 112 mph (180 km/h, 97 kn) (PA-5)[2]
• Stall speed: 45 mph (72 km/h, 39 kn) (PA-5)[2]
• Range: 520 mi (840 km, 450 nmi)
• Service ceiling: 18,000 ft (5,500 m) (PA-5)[2]
• Rate of climb: 1,100 ft/min (5.6 m/s) (PA-5)[2]
• Wing loading: 12.1 lb/sq ft (59 kg/m²)
• Power/mass: 13.8 lb/hp (8.4 kg/kW)