
Designed by H Sherman Tharpe, two 1929 Sierra were built with ATC 2-151. Priced at $8,000 and designated BLW-1 and BLW-2 registered NX215H and NX/NR7713, the latter as San Franciscan in unsuccessful endurance record attempts June-Aug 1929 at Mills Field, San Francisco (piloted by Jim Warner). It is said to have been sold after WW2 to someone in South America.
The design reappeared in the Hawke Duster.
Engine: 130hp Comet
Wingspan: 36’0″
Length: 25’8″
Useful load: 909 lb
Max speed: 125 mph
Cruise: 100 mph
Stall: 47 mph
Range: 400 mi
Seats: 3