The Christavia Mk I is a Canadian two-seats in tandem homebuilt aircraft designed by Ron Mason. The aircraft is supplied in the form of plans for amateur construction. Designed for missionary flying in Africa, the aircraft's name means "Christ-in-Aviation". The Christavia Mk II is a side-by-side configuration version. The Christavia Mk I was first completed and registered as a Christavia CA-05 with Transport Canada on October 1, 1981 and first flew in 1982. Over 350 had been completed and flown by 2002. The Christavia is a single engine, high wing, conventional landing gear-equipped aircraft. The fuselage is of 4130 steel tube construction. The wings are flapless, predominantly wooden, use a custom Mason airfoil design and are supported by dual wing struts. The exterior is finished with aircraft fabric covering. The acceptable power range is 65 to 100 hp (48 to 75 kW) and the standard powerplant used is the 65 hp (48 kW) Continental A65 four stroke four cylinder horizontally opposed piston aircraft engine. Plans are marketed by Aircraft Spruce & Specialty Co. Ron Mason sold the rights to the Christavia series of aircraft to Aircraft Spruce and no longer supplies the plans or support. The designer estimated the construction time as 2000 hours. In January 2016 forty-two examples of the Christavia series of aircraft were registered with Transport Canada and sixty-one in the United States with the FAA. Variants Christavia Mk I Two seat seats in tandem model.[6] Christavia Mk II Two seat side-by-side model, with otherwise similar specifications to the Mk I.[7] Christavia Mk IV Four place model with 150 hp (112 kW) engine recommended.