__NOTOC__ The MacDonald S-20 is a single-seat sport aircraft that was designed in the United States in the early 1970s and marketed for

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.Taylor 1989, 620 The aircraft is a conventional, low-wing cantilever monoplane with fixed tailwheel undercarriage and an open cockpit.''Jane's All the World's Aircraft 1977–78'', 546 Construction is of metal throughout, with a forward fuselage of welded steel tube construction, with the rear fuselage built up of aluminium bulkheads and

longeron In engineering, a longeron and stringer is the load-bearing component of a framework. The term is commonly used in connection with aircraft fuselages and automobile chassis. Longerons are used in conjunction with stringers to form structural ...

s. The wings and tail are also of aluminium construction, and the entire aircraft is skinned in the same material.

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s are used extensively to simplify construction. The S-20 designation was applied to the prototype (registration N106AB), while aircraft built from the plans were designated S-21. In 2009 and 2010 changes were made to the original design to add a cockpit canopy, engine cowling and electrical system, including an avionics bus and starter motor. Aircraft with these changes are designated S-22.

Specifications (S-20)

Notes

References

* * * {{cite web , last1=MacDonald , first1=Robert , title=PLANS FOR THE MACDONALD S-21 AND S-22 AMATEUR-BUILT AIRPLANES , url=http://macdonalds21.com , website=MacDonald S-21 , access-date=3 October 2021 1970s United States sport aircraft Homebuilt aircraft Low-wing aircraft Aircraft first flown in 1972