The first aircraft of the Serie E family was a low-wing monoplane with registration number 2-E-98, which was dubbed "Sonora", this airplane made its first flight on March 2, 1922. It was powered by an
le Rhône 9J 9-cylinder rotary engine, exceeding expectations, with performance significantly higher than similar aircraft at the time. Despite its benefits, the plane was not produced in series, because for was the Technical Consultant of the Aviation Department
Ralph O'Neill, the aircraft could not be used for military purposes. The "Sonora" was in service with the Mexican Air Force until 1925 and later dismantled, being sold to a private individual. Ángel Lascurain and Antonio Sea made a redesign of the "Sonora", this time it was a high-wing monoplane that received the registration 3-E-130 and was nicknamed "
Tololoche", which made its first flight at the end of March 1923. The "Tololoche" was powered by a 160-horsepower Le Rhône 18E air-cooled 18-cylinder rotary engine in 2 rows, also it had two machine guns synchronized with the propeller. Fuselage was made in a monocoque structure covered entirely in wood. Wings were semi-rigid covered with
plywood, which were easy to disassemble by using two pins. In June 1923, a prototype similar to the "Tololoche" was built but with larger dimensions, which received the registration 4-E-131 and was nicknamed "Quetzalcóatl" or "Tololoche grande" because of its great resemblance to the "Tololoche". The "Quetzlcóatl" was powered by a
BMW IIIa 6-cylinder water-cooled in-line engine and its fuselage was mostly built of wood. Four "Quetzlcóatl" were built, participating in observation and bombing flights during the
Delahuertista rebellion. Another prototype that was built almost simultaneously with the "Quetzalcoatl", received the registration 5-E-132, which was nicknamed "Mexico", this airplane had two seats side by side and was powered by an le Rhône engine. It had his first flight on 21 August 1923. ==Variants==