W.Green, G.Swanborough The Complete Book of Fighters

THOMAS-MORSE MB-1 USA

   The Thomas-Morse Aircraft Corporation, formed in January 1917 by a merger of the Thomas Brothers Aeroplane Company with the Morse Chain Works, established itself with the S-4, the first aircraft specifically designed for fighter pilot training. Late in 1917, the designer of the S-4, B Douglas Thomas (unrelated to the founding brothers), initiated design of a two-seat fighter, the MB-1. A parasol monoplane primarily of wooden construction and powered by a 400 hp Liberty 12 water-cooled 12-cylinder Vee-type engine, the MB-1 represented an exercise in achieving minimum structural weight in order to enhance performance. All metal parts were provided with lightening holes - even the control column being perforated - and plywood bulkheads featured large cut-outs, the result being inadequate strength. The undercarriage of the first of two MB-1s collapsed during the first attempted take-off early in 1918, and although it has been alleged that the MB-1 was never flown, repairs were performed on the first prototype and the aircraft was flown once, crashing following take-off. The two airframes were delivered to McCook Field, but all further testing was prudently abandoned in favour of the more orthodox MB-2.

Loaded weight, 2,375 lb (1077 kg).
Span, 37 ft 0 in (11,28 m).
Length, 22 ft 0 in (6,70m).

J.Forsgren The Thomas-Morse MB-3 (A Centennial Perspective on Great War Airplanes 60)

The Thomas-Morse MB-1

  The MB-1 was a two-seat parasol-wing pursuit of mixed wood and metal construction, powered by a 400 h.p. geared Liberty 12 engine. The engine was transported to Ithaca in a guarded wagon. Work on the MB-1 was initiated in late 1917 by the British designer Benjamin Douglas Thomas. Although sharing the same last name, B D Thomas was not related to the Thomas brothers. Incidentally, B D Thomas' previous work included the Curtiss JN two-seat tractor biplane, better known as the 'Jenny'.
  Two MB-1 prototypes were ordered, one of which was to be used for static tests. In order to achieve the lowest possible airframe structural weight, lightening holes were cut into the plywood bulkheads and various metal components. Amazingly, lightening holes were also included in the metal control column! This made the MB-1 airframe prone to structural failure. Nevertheless, the empty weight of the airframe amounted to 2,000 lb (908 kg), to which the 900 lb (408,6 kg) heavy engine was added. Presumably, this caused some problems with the centre of gravity. According to aviation historian R.L. Bliss, the MB-1 "resembled a dragonfly on steroids".
  The armament consisted of four machine guns, including two synchronized forward-firing guns and two Lewis guns in a scarff mounting in the rear seat. Uniquely, a downwards-firing Winchester rifle was also carried. Even before the start of the flight trials, one of the two MB-1 prototypes suffered damage when the tail skid fitting broke off when the aircraft was parked in a hangar. The first flight attempt at the icy surface of Lake Cayuga near Ithaca in early 1918 ended in disaster when the undercarriage collapsed prior to take-off. Subsequently repaired, the prototype managed to struggle into the air but crashed moments after taking off. The two prototypes were then transferred to McCook Field, where they remained firmly grounded. Following arrival at McCook Field, the pair of MB-1s were not allotted serial numbers in the sequential numeric 'P' test series. MB-1 development was quickly abandoned in favour of the two-seat MB-2.

Thomas-Morse MB-1 Technical Data
   Wingspan: 37 ft (11,28 m)
   Length: 22 ft (6,7 m)
   Loaded weight: 2,375 lb (1,077 kg)