The resulting engine had better high-altitude performance and entered production in 1938. However, the engine proved unreliable and suffered from failure of gears in the reduction gearbox. Later the M-88 was designed to address the shortcomings of the M-87.
The resulting engine boasted superior performance at high altitudes and entered mass production in 1938. However, it proved to be unreliable due to gearbox problems. Later, the M-88 was developed to overcome the limitations of the M-87.