Schweizer SGS 1-34

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SGS 1-34
Schweizer SGS 1-34 with terminal velocity dive brakes deployed.
Manufacturer Schweizer Aircraft Corporation
Type designation SGS 1-34
Competition class Standard Class
Designer Ernest Schweizer
First flight 1969
Number built 93
Crew 1
Length 25 ft 5 in (7.8 m)
Height 7 ft 6 in (2.31 m)
Wingspan 49.2ft. (15.0 m)
Wing area 151 sq. ft. (14.03 m²)
Aspect ratio 16
Wing profile Root:Wortmann FX 61-163 Tip:Wortmann FX 61-126
Empty mass 550 lb. (250 kg)
Water ballast None (one was modified)
Maximum mass 840 lb. (381 kg)
Maximum speed 142 MPH
Maneuver speed 115 MPH
Stall speed 36 - 38 MPH
Minimum sink rate 2.1 fps at 47 MPH
Best glide ratio 34 at 55 MPH
Schweizer SGS 1-34 showing wing planform. The tire is used to secure the wing in windy conditons.
Schweizer SGS 1-34 showing wing planform. The tire is used to secure the wing in windy conditons.
Schweizer SGS 1-34, front view showing air vent intake
Schweizer SGS 1-34, front view showing air vent intake
Schweizer SGS 1-34 on take-off
Schweizer SGS 1-34 on take-off
Schweizer SGS 1-34 being towed by a Champion 7GCAA Citabria
Schweizer SGS 1-34 being towed by a Champion 7GCAA Citabria

The Schweizer SGS 1-34 is a United States Standard Class, single-seat, high-wing glider built by Schweizer Aircraft of Elmira, New York.[1]

The 1-34 was designed over a number of years in the mid-1960s and first flew in 1969.[2]

By the time the 1-34 was introduced it was no longer competitive in the Standard Class, but has proven very successful as a club aircraft.[1][3]

Contents

[edit] Development

The 1-34 was designed over several years to spread out the development costs. At the time the design work on the aircraft was started the Standard Class was new and described a very simple aircraft with terminal velocity dive brakes, fixed landing gear and no water ballast. By the time the 1-34 had flown in 1969 the Standard Class rules had changed to allow essentially unrestricted sailplanes with a 15 metre (49.2 feet) wingspan.[3]

The SGS 1-34 is of all metal aluminum semi-monocoque construction. All surfaces are aluminum covered, with the exception of the rudder which is covered in aircraft fabric.[1]

The 1-34 has the originally specified terminal velocity dive brakes, that limit the glider to below redline speeds in a vertical dive. Developing and testing these proved expensive and time consuming and this also extended the aircraft's development time.[3]

The 1-34 was the first Schweizer design to depart from using a NACA airfoil. The 1-34 has no wing washout and instead uses a Wortmann FX 61-163 airfoil at the wing root transitioning to a Wortmann FX 61-126 airfoil at the wing tip. The tip airfoil stalls at a higher angle of attack, ensuring that the wing root stalls first.[1]

The one company concession to the changing Standard Class rules was the development of a retractable landing gear version of the 1-34, designated as the SGS 1-34R.[1]

The 1-34 also features in-flight adjustable rudder pedals and a two-way adjustable seat to accommodate pilots of different heights.[1]

The 1-34 was flown in Standard Class competitions, but was out-performed by the new fiberglass European gliders, such as the Glasflügel H-201 Standard Libelle.[3]

During the protracted development process, Schweizer Aircraft was aware that the 1-34 would be overtaken by the changes in class rules and also by the performance of the newer European fiberglass sailplanes, but continued development of the SGS 1-34 anyway. The company identified that there was demand from private owners and especially clubs and commercial operations for a simple, rugged single seat glider with greater performance than the 1-26.[3]

In service the 1-34 has proven to be a popular club aircraft and ideal for completing badge flights in. If a greater number of 1-34s had been built, Schweizer indicated that it would have become another one-design class, similar to the 1-26.[3]

The 1-34 type certificate is currently held by K & L Soaring of Cayuta, New York. K & L Soaring now provides all parts and support for the Schweizer line of sailplanes.[4][5]

[edit] Variants

1-34
The original 1-34 model was certified under type certificate G3EA on 16 October 1969.[4]
1-34R
The retractable gear 1-34R was added to type certificate G3EA on 15 June 1971.[4]

[edit] Modifications

At least one 1-34 has been highly modified.[1]

Bob Park's 1-34R, registered N17974, was damaged when a hurricane passed through Georgia and resulted in a hangar collapse. The 1-34R was rebuilt with a V-tail and ballast tanks mounted in the wings that hold 230 lbs (105 kg) of water. The aircraft was subsequently registered in the experimental Racing - Exhibition category.[2][6][7]

[edit] In service

In May 2008 there were still 63 1-34s and six 1-34Rs registered in the USA[8] and 5 SGS 1-34s in Canada.[9]

The USAF designation for the SGS 1-34 is TG-6.

[edit] See also

List of gliders

[edit] References

  1. ^ a b c d e f g Said, Bob: 1983 Sailplane Directory, Soaring Magazine, page 32. Soaring Society of America, November 1983. USPS 499-920
  2. ^ a b Activate Media (2006). SGS 1-34 Schweizer. Retrieved on 2008-05-25.
  3. ^ a b c d e f Schweizer, Paul A: Wings Like Eagles, The Story of Soaring in the United States, page 241. Smithsonian Institution Press, 1988. ISBN 0-87474-828-3
  4. ^ a b c Federal Aviation Administration (September 2007). GLIDER DATA SHEET NO. G3EA. Retrieved on 2008-05-25.
  5. ^ K & L Soaring (undated). K & L Soaring, LLC. Retrieved on 2008-04-05.
  6. ^ Said, Bob: 1983 Sailplane Directory, Soaring Magazine, page 63. Soaring Society of America, November 1983. USPS 499-920
  7. ^ Federal Aviation Administration (May 2008). FAA Registry. Retrieved on 2008-05-31.
  8. ^ Federal Aviation Administration (May 2008). FAA Registry. Retrieved on 2008-05-25.
  9. ^ Transport Canada (May 2008). Canadian Civil Aircraft Register. Retrieved on 2008-05-25.

[edit] External links