Schweizer SGS 1-23
 The Schweizer SGS 1-23 is a United States Open and Standard Class single-seat mid-wing glider built by Schweizer Aircraft of Elmira New York.The original standard 1-23 was introduced in 1948. The aircraft quickly became the most numerous competition and performance sailplane in the USA. A total of 93 of all sub-models were built by the time production was completed in 1967.