The Stearman LT-1 (Light Transport-1) was a late 1920s American
biplane
A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...
, carrying four passengers plus mail.
Design and development
The LT-1 was a slightly enlarged version of the
Stearman M-2 Speedmail
The Stearman M-2 Speedmail (nicknamed the Bull Stearman) was a mail-carrier aircraft produced by the Stearman Aircraft Company of Wichita, Kansas. It first flew in January 1929. The Speedmail was a single-seat biplane, with two large cargo compa ...
with four passengers in an enclosed cabin and space for of mail. It was an unequal span,
single bay biplane, its lower span only 70% that of the upper and with only 40% of its area. The wings were built around twin
spars
The United States Coast Guard (USCG) Women's Reserve, also known as the SPARS (SPARS was the acronym for "Semper Paratus—Always Ready"), was the women's branch of the United States Coast Guard Reserve. It was established by the United States ...
so, because of the narrower
chord
Chord may refer to:
* Chord (music), an aggregate of musical pitches sounded simultaneously
** Guitar chord a chord played on a guitar, which has a particular tuning
* Chord (geometry), a line segment joining two points on a curve
* Chord ( ...
of the lower wings, the leading members of the N-form
interplane struts which joined the wing spars leaned forward. Both upper and lower wings were set with 2° of
dihedral and both carried
ailerons, which were externally interconnected. Navigation and landing lights, the latter in streamlined underwing housings, were standard.
[
The LT-1 was powered by a Pratt & Whitney Hornet ]radial engine
The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders "radiate" outward from a central crankcase like the spokes of a wheel. It resembles a stylized star when viewed from the front, and is ca ...
, nose-mounted with its nine cylinderheads exposed for cooling. Behind the engine there was a mail compartment and behind that a windowed cabin seated four passengers, provided with airspeed meter, altimeter and map box. Its pilot had an open cockpit with windscreen and streamlined headrest built into the rounded upper fuselage decking.[
Its tail was conventional, with a ]tailplane
A tailplane, also known as a horizontal stabiliser, is a small lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters and gyroplane ...
mounted on top of the fuselage and a cropped triangular fin
A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fin ...
with a rather angular balanced rudder
Balanced rudders are used by both ships and aircraft. Both may indicate a portion of the rudder surface ahead of the hinge, placed to lower the control loads needed to turn the rudder. For aircraft the method can also be applied to elevators and ...
.[
The ]undercarriage
Undercarriage is the part of a moving vehicle that is underneath the main body of the vehicle. The term originally applied to this part of a horse-drawn carriage, and usage has since broadened to include:
*The landing gear of an aircraft.
*The ch ...
was also conventional, though with a tail wheel rather than a skid. Its mainwheels were on split axles and rearward drag struts, both mounted centrally on the fuselage underside, with vertical shock-absorbing legs.[
]
Operational history
The date of the LT-1's first flight is not known but it was certificated in 1929. The prototype was destroyed not long after its first flight by a wind storm. At least one was used by Interstate Airlines until 1934, after which it operated in China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
.[
]
Specifications
See also
References
{{Stearman Aircraft
Sesquiplanes
Single-engined tractor aircraft
1920s United States civil utility aircraft
LT-1