Schweizer SGS 2-33

The Schweizer SGS 2-33 is a United States two-seat, high-wing, strut-braced, training glider built by Schweizer Aircraft of Elmira, New York.Schweizer, Paul A: "Wings Like Eagles, The Story of Soaring in the United States", pages 227-327. Smithsonian Institution Press, 1988. ISBN 0-87474-828-3]

The 2-33 was designed to replace the Schweizer 2-22, from which it was derived. The aircraft first flew in 1965 and production was started in 1967. Production was completed in 1981.

From its introduction until the late 1980s, the 2-33 was the main training glider in North America.

Background

The SGU 2-22 two seat training glider was introduced in 1945 and quickly became the most popular training glider in the USA.Said, Bob: "1983 Sailplane Directory, Soaring Magazine", page 28. Soaring Society of America, November 1983. USPS 499-920]

By the early 1960s it became obvious to Schweizer Aircraft that a replacement for the 2-22 was needed. At that time the single seat Schweizer SGS 1-26 was becoming very popular for one-design competition flying. The company realized that the new trainer should have similar performance to the 1-26, in order to be used as the 1-26's two seat transition trainer.

SGU 2-22 production was ended at serial number 258 in 1967 to commence production of the new model.

Development

The SGS 2-33, indicating "Schweizer Glider, Sailplane, 2 Seats, Model 33", was designed by Ernest Schweizer. The aircraft was a derivative of the 2-22, which in turn was based on the SGU 1-7 single place glider of 1937. The 2-33 retained the 2-22 and 1-7's metal wing, single spar and single strut arrangement. Schweizer Aircraft: "The Schweizer 2-33 Super Club Sailplane", pages 1-4. Schweizer Aircraft undated]

The 2-33 was manufactured in three variants and remained in production for 14 years. Production was only curtailed when demand dropped off due to the import of higher-performance two-place sailplanes from Europe.

The 2-33 received type certificate G3EA on 10 February 1967. cite web|url = http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/6f7bc89ce0cbcd1f862573b1005bb768!OpenDocument&Click=852566E20067A2FD.e0492853585af5cc852566270055c245/$Body/0.1B9E|title = GLIDER DATA SHEET NO. G2EA |accessdate = 2008-05-31|last = Federal Aviation Administration|authorlink = |year = 2007|month = September]

A number of 2-33s were delivered as kits to the purchaser and designated as SGS 2-33AK. These were accepted by the Federal Aviation Administration as certified aircraft and not amateur-builts, subject to conditions:

cquote|Each Model SGS 2-33A glider assembled from a kit is designated Model SGS-2-33AK. These K models will be eligible for an airworthiness certificate when accompanied by an affidavit certifying that the glider is constructed in exact accordance with the approved drawings and manual, and that the parts and materials furnished by the manufacturer in the kit have been used; and further when the following inspections have been satisfactorily passed: (a) An inspection for workmanship, materials, and conformity before any covering is applied. (All woodwork may be sealed.)
(b) A final inspection of the completed glider.
(c) Check of flight characteristics.

The 2-33 type certificate is currently held by K & L Soaring of Cayuta, New York who now provide all parts and support for the Schweizer line of sailplanes. cite web|url = http://klsoaring.com/|title = K & L Soaring, LLC|accessdate = 2008-04-05|last = K & L Soaring|authorlink = |year = undated]

Construction

The 2-33 was designed to be rugged, easy to maintain and with a high degree of crashworthiness.

The 2-33 has a welded steel tube fuselage covered in aircraft fabric. The single-spar, aluminum structure wings are tapered from mid-span and feature top and bottom balanced divebrakes. The wings are covered in aluminum stressed skin. The tail surfaces are made from welded steel tube covered in aircraft fabric.

The 2-33 has a fiberglass nose cone and a one-piece molded front canopy. Access to the rear seat is via door on the right-hand side. Instruments are fitted in the front cockpit only. The 2-33 has a four-position bungee trim system.

Variants

;SGS 2-33

:The original 2-33 was certified on 10 February 1967. ;SGS 2-33A

:The "A" model incorporated some minor changes, including a larger rudder. It was certified on 7 March 1968.

;SGS 2-33AK

:The "AK" model was an "A" model completed by the buyer from a kit. It was certified on 19 April 1973.

Military Service

The United States Air Force Academy operated 13 2-33s as the TG-4A until they were replaced by the TG-10B (L-23 Super Blanik) in 2002. The USAFA TG-4s were all donated to other US government agencies, such as the Civil Air Patrol or to aviation museums. cite web|url = http://www.usafa.af.mil/tu/306ftg/94fts/tg-4a.cfm|title = TG-4A|accessdate = 2008-05-31|last = United States Air Force Academy|authorlink = |year = 2008|month = May] [cite web | title = TG-4 Sailplane | publisher = Global Security.org | url = http://www.globalsecurity.org/military/systems/aircraft/tg-4.htm | accessdate = 2007-02-28]

Under the 1962 United States Tri-Service aircraft designation system the USAF 2-33 was designated as the TG-4A. This can cause confusion with a World War Two training glider made by Laister-Kauffman and used by the United States Army Air Forces from 1941 to 1947. The Laister-Kauffman LK-10B also bore the designation TG-4A, but from an earlier USAAF designation system. cite web|url = http://www.sailplanedirectory.com/PlaneDetails.cfm?planeID=200|title = LK-10A Laister-Kauffmann |accessdate = 2008-05-31|last = Activate Media|authorlink = |year = 2006] Andrade, John: "U.S.Military Aircraft Designations and Serials since 1909", Page 169 and 170, Midland Counties Publications, 1979, ISBN 0 904597 22 9]

In service

In May 2008 there were still 358 SGS 2-33s registered in the USA. These included: [ cite web|url = http://registry.faa.gov/aircraftinquiry/acftinqSQL.asp?striptxt=233&mfrtxt=Schweizer&cmndfind.x=16&cmndfind.y=15&cmndfind=submit&modeltxt=2-33|title = FAA Registry|accessdate = 2008-05-31|last = Federal Aviation Administration|authorlink = |year = 2008|month = May]

*65 SGS 2-33
*291 SGS 2-33A
*2 SGS 2-33AK

There were 89 2-33s registered in Canada in May 2008, including: cite web|url = http://www.tc.gc.ca/aviation/activepages/ccarcs/aspscripts/en/quicksearch.asp|title = Canadian Civil Aircraft Register|accessdate = 2008-05-31|last = Transport Canada|authorlink = |year = 2008|month = May]

*19 SGS 2-33
*70 SGS 2-33A

Museums

There is a 2-33A in the Wings Over the Rockies Air and Space Museum, but none in the collection of the National Soaring Museum. cite web|url = http://www.soaringmuseum.org/collection.html|title = Sailplanes in Our Collection|accessdate = 2008-05-19|last = Munson|first = J.|authorlink = |year = undated] .

Operators

*Air Cadet League of Canada - 77.

pecifications

aerospecs
ref="Pre-Course Information Package for Glider Candidates" [cite paper | author =Regional Gliding School (Pacific) | title =Pre-Course Information Package for Glider Candidates | date =2005 | url =http://www.cadets.net/pac/support/pdf/pre_study_glider05.pdf | format =PDF | accessdate =2007-01-01]
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ee also

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* List of gliders

References

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