The 1-29 is a development of the Schweizer SGS 1-23 that utilizes a 1-23 fuselage and a newly constructed set of 49.2 foot (15.0 m) span wings.[1][3]
The aircraft was constructed to study the feasibility of producing improved boundary layer laminar flow on a metal-winged sailplane. Only one SGS 1-29 was produced and the project was not pursued further.[1][2][3]
In the mid-1950s the SGS 1-23 was in full production and through successive models was performing very well in competition. By 1957 the development of fiberglass-reinforced plastic affected the production of many sporting goods, such as boats and fishing rods. Schweizer Aircraft thought it was only a matter of time before a fiberglass sailplane was produced. This concern was borne out in 1965, when two German fiberglass sailplanes were entered in the world championships.[2]
Schweizer Aircraft evaluated the use of fiberglass for sailplane construction and rejected it for several reasons:[2]
The high cost of demonstrating to the Federal Aviation Administration that this new material could safely be used for aircraft primary structure.[2]
Problems with crash resistance of fiberglass structures in high impact accidents.[2]
Of these, only the SGS 1-29 proceeded to prototype stage.[2][3]
Design and development
The 1-29 was constructed using a modified SGS 1-23Gfuselage. New wings were built for the aircraft to determine if better laminar flow could be achieved on a metal wing.[1][3]
The wings were all-metal and of constant chord. The wing ribs were identical and created from a single master die to ensure uniformity. The wing features a thick, deep spar to reduce wing flexing and "oil-canning" that might interrupt laminar flow. The wing was assembled using flush rivets and has balanced top and bottom dive brakes.[1][3]
The aircraft first flew in 1958 and flight testing was reported by Schweizer Aircraft as on-going through 1959.[2]
The 1-29 program did yield positive results. The standard production model SGS 1-23H-15 with the same fuselage and wingspan as the 1-29 and a NACA 43012A airfoil, produced a best glide ratio of 29:1. With its laminar flow wing and NACA 63-618 airfoil the 1-29 recorded a 34:1 glide ratio, an improvement of 15%.[3]
The 1-29 design was never certified and the sole aircraft that was built is an experimental aircraft in the "racing, exhibition" class and registered as N3898A.[3][5]
Operational history
The 1-29 was flown in at least three US national competitions by Paul A Schweizer, Bill Ivans and Tom Smith.[3]
Aircraft on display
Once the 1-29 test program was complete, the aircraft was donated to the National Soaring Museum where it is currently listed as being in storage.[6]
^ abcdeActivate Media (2006). . Archived from the original on August 8, 2007. Retrieved May 27, 2008.
^ abcdefghijklSchweizer, Paul A: Wings Like Eagles, The Story of Soaring in the United States, pages 159-209. Smithsonian Institution Press, 1988. ISBN0-87474-828-3
^ abcdefghiSaid, Bob: 1983 Sailplane Directory, Soaring Magazine, page 32. Soaring Society of America, November 1983. USPS 499-920
^ abcdSmithsonian Institution (2004). "Directory of Airplanes". Retrieved May 13, 2008.
^Munson, J. (n.d.). . Archived from the original on May 16, 2011. Retrieved April 15, 2008.
External links
Wikimedia Commons has media related to Schweizer SGS 1-29.
February 01, 2023
schweizer, american, single, seat, wing, experimental, laminar, flow, airfoil, glider, built, schweizer, aircraft, elmira, york, 29paul, schweizer, 1963, soaring, championships, harris, hill, elmira, nyrole, experimental, standard, class, sailplanenational, or. The Schweizer SGS 1 29 is an American single seat mid wing experimental laminar flow airfoil glider built by Schweizer Aircraft of Elmira New York 3 SGS 1 29Paul Schweizer s 1 29 at the 1963 US Soaring Championships at Harris Hill Elmira NYRole Experimental Standard class sailplaneNational origin United StatesManufacturer Schweizer Aircraft CorporationDesigner Ernest Schweizer 1 First flight 1958 2 Number built 1The 1 29 is a development of the Schweizer SGS 1 23 that utilizes a 1 23 fuselage and a newly constructed set of 49 2 foot 15 0 m span wings 1 3 The aircraft was constructed to study the feasibility of producing improved boundary layer laminar flow on a metal winged sailplane Only one SGS 1 29 was produced and the project was not pursued further 1 2 3 Contents 1 Background 2 Design and development 3 Operational history 4 Aircraft on display 5 Specifications 6 See also 7 References 8 External linksBackground EditIn the mid 1950s the SGS 1 23 was in full production and through successive models was performing very well in competition By 1957 the development of fiberglass reinforced plastic affected the production of many sporting goods such as boats and fishing rods Schweizer Aircraft thought it was only a matter of time before a fiberglass sailplane was produced This concern was borne out in 1965 when two German fiberglass sailplanes were entered in the world championships 2 Schweizer Aircraft evaluated the use of fiberglass for sailplane construction and rejected it for several reasons 2 The high cost of demonstrating to the Federal Aviation Administration that this new material could safely be used for aircraft primary structure 2 Problems with crash resistance of fiberglass structures in high impact accidents 2 The unknown service life of fiberglass 2 The high degree of manual labor required to do fiberglass lay ups at that time and the associated cost 2 The company decided to concentrate on getting the best performance from the material that it knew best aluminum 2 Schweizer created several design studies of new sailplanes in the mid 1950s These included 2 4 Schweizer 2 27 4 Schweizer 7 28 4 Schweizer SGS 1 29 4 Of these only the SGS 1 29 proceeded to prototype stage 2 3 Design and development EditThe 1 29 was constructed using a modified SGS 1 23G fuselage New wings were built for the aircraft to determine if better laminar flow could be achieved on a metal wing 1 3 The wings were all metal and of constant chord The wing ribs were identical and created from a single master die to ensure uniformity The wing features a thick deep spar to reduce wing flexing and oil canning that might interrupt laminar flow The wing was assembled using flush rivets and has balanced top and bottom dive brakes 1 3 The aircraft first flew in 1958 and flight testing was reported by Schweizer Aircraft as on going through 1959 2 The 1 29 program did yield positive results The standard production model SGS 1 23H 15 with the same fuselage and wingspan as the 1 29 and a NACA 43012A airfoil produced a best glide ratio of 29 1 With its laminar flow wing and NACA 63 618 airfoil the 1 29 recorded a 34 1 glide ratio an improvement of 15 3 The 1 29 design was never certified and the sole aircraft that was built is an experimental aircraft in the racing exhibition class and registered as N3898A 3 5 Operational history EditThe 1 29 was flown in at least three US national competitions by Paul A Schweizer Bill Ivans and Tom Smith 3 Aircraft on display EditOnce the 1 29 test program was complete the aircraft was donated to the National Soaring Museum where it is currently listed as being in storage 6 Specifications EditGeneral characteristics Crew One Wingspan 49 ft 3 in 15 00 m Wing area 154 sq ft 15 3 m2 Aspect ratio 15 75 Airfoil NACA 63 618 Empty weight 465 lb 224 kg Gross weight 750 lb 340 kg Performance Maximum glide ratio 34 at 52 mph 83 km h Rate of sink 123 ft min 0 63 m s See also EditRelated lists List of experimental aircraft List of glidersReferences Edit a b c d e Activate Media 2006 SGS 1 29 Schweizer Archived from the original on August 8 2007 Retrieved May 27 2008 a b c d e f g h i j k l Schweizer Paul A Wings Like Eagles The Story of Soaring in the United States pages 159 209 Smithsonian Institution Press 1988 ISBN 0 87474 828 3 a b c d e f g h i Said Bob 1983 Sailplane Directory Soaring Magazine page 32 Soaring Society of America November 1983 USPS 499 920 a b c d Smithsonian Institution 2004 Directory of Airplanes Retrieved May 13 2008 Federal Aviation Administration May 2008 FAA Registry Retrieved May 27 2008 Munson J n d Sailplanes in Our Collection Archived from the original on May 16 2011 Retrieved April 15 2008 External links Edit Wikimedia Commons has media related to Schweizer SGS 1 29 Photo of the SGS 1 29 Retrieved from https en wikipedia org w index php title Schweizer SGS 1 29 amp oldid 1064853351, wikipedia, wiki, book, books, library,
