10/31/2011. Remarks by Walter van Tilborg: "This fully aerobatic single-seat sport biplane was designed by Gordon Price and marketed, for amateur construction, by Ultimate Aircraft Corporation (later Ultimate Aerobatics Ltd.) in several versions. The prototype aircraft first flew on October 4 or 6, 1985. The name Albertan was introduced after the test program had already started, but later usually the type was referred to as the Ultimate Model 10.

The Ultimate 10-100 was the initial model, largely similar to the prototype and also fitted with one 100 hp Continental O-200-A engine. Only a prototype aircraft was built, by the designer, this aircraft was damaged in an accident, but was then rebuilt.

The Ultimate 10-150 was similar to the 10-100, but fitted with a more powerful 150-160 hp Lycoming IO-320/O-320 series engine, none were produced.

The Ultimate 10-180 had a slightly longer nose and one 180 hp Lycoming O-360 engine, at least one was produced in Canada by Stefan Trischuk: C-FGYD c/n 1A.

The Ultimate 10-200S was largely based on the 10-180 and was stressed for engines in the 200-220+ hp range and like the 10-180 slightly longer. Only a few aircraft of this model were built (in Canada, Denmark, USA) and engines used were Lycoming AEIO-360 series. Built in 1994 Poul Münsberg of Slangerup, Danmark, the pictured aircraft is still registered to Münsberg.

The Ultimate 10-300, also known as the 10-300S, was designed for engines up to 375 hp. The first 10-300 aircraft, built by the designer, made the first flight during the summer of 1987 and used one 300 hp Lycoming AEIO-540 engine. It was later sold in Finland where it was still active in 2006. The 10-300 variant had increased wingspan and again, a longer fuselage. Further examples was built in Canada, France and the USA.

The Ultimate 20 was a larger two-seat development.

Bateleur 200 was the designation for a 10-200S completed in the USA in 1993 by Richard J. Brand. The aircraft had one 200 hp Lycoming AEIO-360-A1D engine and incorporated several modifications The aircraft (nicknamed "Plumb Crazy") was used for air show work and was lost in a (non-fatal) crash on November 11, 2007.

Marketing of the Ultimate 10 and 20 was later taken over by Streamline Welding, Inc. Examples of the Ultimate 10-300 were built in various countries, including the USA, Canada."