Butler Blackhawk

Summary

The Butler Blackhawk and the Skyway from which it was developed were American three-seat open-cockpit single engine biplanes of the late 1920s that were built in small numbers immediately prior to having their intended production run interrupted by the onset of the Great Depression.

Blackhawk
Role Utility biplane
National origin United States
Manufacturer Butler Aircraft Corporation[1][note 1]
Designer Waverly M. Stearman[1]
First flight 4 October 1928[2]
Introduction 1929
Status Retired
Produced 1928-1929
Number built 13[note 2]

Design and development edit

The fuselage was built from chromium-molybdenum alloy steel tubing faired to shape with light wooden battens and covered in doped aircraft linen.[3][4] Separate cockpits were provided for the pilot, in the rear, with the two passengers up front, with a baggage compartment behind the pilot.[5] Unusually, the pilot was provided with dual engine controls, one on each side of the cockpit.[3] Like the fuselage, the empennage was built up from welded chromium-molybdenum alloy steel and covered in fabric with the elevators being adjustable in flight from the cockpit.[5][4]

The biplane wings were built up around two solid spruce spars with built-up plywood ribs forming the airfoil section.[5] No center section was used, as the wing panels were joined along the centerline. While the main fuel tank was in the fuselage, it was supplemented with smaller gravity tanks in each upper wing root.[5] Frise-type ailerons actuated by push-pull tubes[4] were fitted to the lower wings only.[5] It was fitted with a split-axle undercarriage.[5]

Variants edit

All variants were powered by a single 220 hp (160 kW) Wright J-5 Whirlwind air-cooled radial engine,[2] although the prototype was initially reported as having a 200 hp (150 kW) J-5.[4]

Skyway (ATC 2-49)
Prototype, two built, one (msn 101) destroyed before being licensed and one (msn 100, NX7857) converted to Blackhawk standard.[2]
Coach
Cabin variant, one built (msn 102, NX146E).[2]
Blackhawk (ATC 135)
Main variant, 11 built, including one converted from Skyway.[2]
Leuthart D
Single Blackhawk (msn 112, NC14422) renamed by purchaser.[2]

Operational history edit

 
Butler Blackhawk with Monocoupe

Butler Manufacturing were producers of pre-fabricated steel buildings, including aircraft hangars who decided to expand into aircraft construction, however shortly after they begin production, the 1929 Stock Market Crash and the onset of the Great Depression began to severe impacted their profitability, both with their main line of business, and with regards to aviation and they almost immediately shut down their production line to preserve their core business. As a result, only 13 serial numbers were allocated.

Art Goebel, known as the winner of the disastrous Dole Air Race in which many of the entrants failed to survive, and for the aerobatic routines he carried out in a Waco ATO, made a test flight from Kansas City, Missouri to San Antonio, Texas in a Blackhawk, and liked it enough to buy one for his personal use.[1]

Hoot Gibson, a famous 1920s and 1930s cowboy actor, bought Blackhawk[3] NC730K serial 105,[6] however, it was while flying a similar Swallow biplane borrowed from a friend that he crashed at the National Air Races in Los Angeles on 3 July 1933, and not the Blackhawk.[7]

Some examples began being used as crop dusters at the end of the 1930s.[3]

Operators edit

  United States
  Mexico
  • Compañía Aeronáutica del Sur operated the first prototype (msn 100) as X-BAHH.[9]

Surviving aircraft edit

Specifications (Butler Blackhawk (ATC 135) ) edit

 
Butler Blackhawk

Data from U.S. Civil Aircraft Vol. 2 (ATC 101 - 200) [3]

General characteristics

  • Crew: One
  • Capacity: Two
  • Length: 24 ft 0 in (7.32 m)
  • Upper wingspan: 34 ft 0 in (10.36 m)
  • Upper wing chord: 64 in (1.6 m)
  • Lower wingspan: 28 ft 6 in (8.69 m)
  • Lower wing chord: 54 in (1.4 m)
  • Height: 9 ft 0 in (2.74 m)
  • Wing area: 295 sq ft (27.4 m2)
  • Upper wing area: 180 sq ft (17 m2)
  • Lower wing area: 115 sq ft (10.7 m2)
  • Empty weight: 1,885 lb (855 kg)
  • Gross weight: 2,900 lb (1,315 kg)
  • Useful load: 1,015 lb (460 kg)
  • Fuel capacity: 70 US gal (260 L; 58 imp gal)[4]
  • Oil capacity: 8 US gal (30 L; 6.7 imp gal)[4]
  • Undercarriage track: 90 in (2.3 m)[4]
  • Powerplant: 1 × Wright J-5 Whirlwind air-cooled radial engine , 220 hp (160 kW)
  • Propellers: 2-bladed metal fixed pitch propeller

Performance

  • Maximum speed: 130 mph (210 km/h, 110 kn)
  • Cruise speed: 110 mph (180 km/h, 96 kn) or 115 mph (185 km/h) if metal cover in place over front cockpit.[3]
  • Minimum control speed: 47 mph (76 km/h, 41 kn)
  • Range: 650 mi (1,050 km, 560 nmi) at cruising speed
  • Service ceiling: 14,000 ft (4,300 m)
  • Time to altitude: 60 seconds to 1,000 ft (300 m)
  • Wing loading: 8.06 lb/sq ft (39.4 kg/m2) [4]
  • Power loading: 13.25 lb/hp (8.06 kg/kW) [4]
  • Fuel consumption: 0.629 lb/mi (0.177 kg/km) [note 3]
  • Fuel consumption: 11.5 US gal (44 L; 9.6 imp gal)/hour

See also edit

Aircraft of comparable role, configuration and era edit

Related lists edit

References edit

Notes edit

  1. ^ Subsidiary of Butler Manufacturing Corp.
  2. ^ Number includes the second prototype Skyway, which was destroyed without having been registered, and the sole cabin variant.
  3. ^ Minimum, based on fuel burn rate of 11.5 US gal (44 L; 9.6 imp gal)/hour at the 110 mph (180 km/h) cruise speed and a weight of 6.02 lb/US gal (0.721 kg/L) for aviation gasoline, such as for 100LL and 80/87 fuels

Citations edit

  1. ^ a b c Juptner, 1964, p.104
  2. ^ a b c d e f Eckland, 2009
  3. ^ a b c d e f Juptner, 1964, p.105
  4. ^ a b c d e f g h i Horsfall, January 1929, p.72
  5. ^ a b c d e f Juptner, 1964, p.106
  6. ^ Hyatt, Gary (12 January 2010). "Blackhawk NC730K". Davis Monthan Airfield. Retrieved 24 April 2020.
  7. ^ Hyatt, Gary (11 December 2013). "SWALLOW F28W NC8730". Retrieved 24 April 2020.
  8. ^ Kansas City Public Library. "Butler Blackhawk Airplane". The Pendergast Years. Retrieved 23 April 2020.
  9. ^ Pentland, 2014
  10. ^ Federal Aviation Administration (23 April 2020). "FAA REGISTRY N-Number Inquiry Results N593H..." Retrieved 23 April 2020.
  11. ^ Kelch Aviation Museum (2015). "1929 Butler Blackhawk". Brodhead, WI. Retrieved 23 April 2020.

Bibliography edit

  • Eckland, K. O. (17 April 2009). "AIRCRAFT Bo to By". Aerofiles.com. Retrieved 23 April 2020.
  • Horsfall, J.E., ed. (January 1929). "The Butler Biplane". Vol. 14, no. 1. New York City: Aeronautical Digest Publishing Corp. p. 72. {{cite magazine}}: Cite magazine requires |magazine= (help)
  • Juptner, Joseph P. (1964). U.S. Civil Aircraft Vol. 2 (ATC 101 - 200). Los Angeles, CA: Aero Publishers, Inc. LCCN 62-15967.
  • Pentland, Andrew (13 June 2014). "Golden Years of Aviation Civil Aircraft Register - Mexico". www.airhistory.org.uk. Leeds, UK. Retrieved 24 April 2020.

External links edit

  • Blackhawk msn 110 N593H having engine run up