Interstate Cadet
Encyclopedia
The Interstate Cadet is an American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
two-seat tandem, high wing, single engine monoplane
Monoplane
A monoplane is a fixed-wing aircraft with one main set of wing surfaces, in contrast to a biplane or triplane. Since the late 1930s it has been the most common form for a fixed wing aircraft.-Types of monoplane:...
light aircraft. Around 320 of these aircraft were produced between the years of 1941 and 1942 by the Interstate Aircraft and Engineering Corporation
Interstate Aircraft
Interstate Aircraft and Engineering Corporation was a small American aircraft manufacturer from April 1937 to 1945, based in El Segundo, California. In 1940 they developed the Cadet, a 2-seat monoplane. The Model S-1B was developed into the XO-63, later redesignated to the XL-6. Two hundred...
based in El Segundo, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. The construction techniques employed were a welded steel tube fuselage
Fuselage
The fuselage is an aircraft's main body section that holds crew and passengers or cargo. In single-engine aircraft it will usually contain an engine, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage which in turn is used as a floating hull...
, wood (spruce) wing structure with metal ribs, and fabric covering, all of which were fairly standard in the 1940s.
The aircraft in its original version (the S1 prototype) was powered by the 50hp Continental A-50 engine, but was soon upgraded (the S1-A-65F variant) to the Continental A-65 engine. This was the mainstay used in most small two-seat aircraft of the time. This aircraft was also used in WW2, being named the L-6A.
It has been argued why this aircraft did not become successful during early 40's. One reason found is that this aircraft cost almost three times the amount of the comparable J-3 Cub
Piper J-3
The Piper J-3 Cub is a small, simple, light aircraft that was built between 1937 and 1947 by Piper Aircraft. With tandem seating, it was intended for flight training but became one of the most popular and best-known light aircraft of all time...
. However, if one were to look at the blue prints between the two aircraft it can be stated that the Cadet is far superior. Its faster, stronger, and can be operated in a more rugged environment. It can operate in the rugged north due to the Oleo strut/Compression spring suspension system. Popular upgrades for this airframe include: larger engines(75/85/90/100hp), better brakes, and a different tailwheel system.
In the late 1960s the type certificate
Type certificate
A Type Certificate, is awarded by aviation regulating bodies to aerospace manufacturers after it has been established that the particular design of a civil aircraft, engine, or propeller has fulfilled the regulating bodies' current prevailing airworthiness requirements for the safe conduct of...
s and tooling were bought by the newly formed Arctic Aircraft
Arctic Aircraft
The Arctic Aircraft Company was founded in Anchorage, Alaska by Bill Diehl in 1975 to produce an updated version of the Interstate Cadet light aircraft as the Arctic Tern. In 1985, the company closed down, and rights to the aircraft went to the Interstate Aircraft Company.-References:This article...
Company. Arctic Aircraft transformed the S-1B1 into a bush plane by upgrading structural elements of the fuselage, landing gear, and wings. This new aircraft, designated the S-1B2, was reconfigured with a Lycoming O-320
Lycoming O-320
The Lycoming O-320 is a large family of 92 different normally aspirated, air-cooled, four-cylinder, direct-drive engines commonly used on light aircraft such as the Cessna 172 and Piper Cherokee. Different variants are rated for 150 or 160 horsepower...
160 HP engine and 82” McCauley
McCauley
-Surname:*McCauley , an English-language surname with multiple etymological origins .-Places:* McCauley, Edmonton, an inner city neighbourhood located in Edmonton, Alberta, Canada....
propeller for increased performance.
In the 1970s, the Model S-1B2 was revived, modernised form, and type certificated in 1975 as the Arctic Tern.
Type certification was also obtained for some of the original Interstate Cadets to use the 160 hp Lycoming O-320 engine but without the full complement of modifications and upgrades provided in the Arctic Tern.
Variants
S-1- Certified in 1940 and powered by a Continental A-50-8Continental O-170|-See also:-References:*Christy, Joe: Engines for Homebuilt Aircraft & Ultralights, pages 43-52. TAB Books, 1983. ISBN 0830623477...
engine.
S-1A
- Certified in 1941 and powered by a Continental A-65-8 engine.
S-1A-65F
- 1941 variant powered by a 65hp Franklin 4AC-176-B2 engine.
S-1A-85F
- 1942 variant powered by a 85hp Franklin 4AC-199-D2 engine.
S-1A-90F
- 1942 variant powered by 90hp Franklin 4AC-199-E2 engine.
S-1B1
- 1942 variant with a Franklin 4ACG-199-H3 engine. Military production as the L-6 Grasshopper.
S-1B2 (Arctic Tern)
- 1975 improved variant of the S-1B1 powered by a Lycoming O-320-A2B or B2BLycoming O-320The Lycoming O-320 is a large family of 92 different normally aspirated, air-cooled, four-cylinder, direct-drive engines commonly used on light aircraft such as the Cessna 172 and Piper Cherokee. Different variants are rated for 150 or 160 horsepower...
engine.
XO-63 Grasshopper
- United States Army designation for one S-1B for evaluation, later designated the XL-6.
L-6A Grasshopper
- United States Army designation for the S-1B1, 250 built.
L-8A Cadet
- United States Army designation for eight S-1As ordered on behalf of the Bolivian Air Force.