Kawasaki Heavy Industries Ltd., Japan's second-largest maker of heavy machinery, said Tuesday it is considering developing a commercial version of a cargo plane being designed for the Self-Defense Forces.

The company will explore the idea after test flights of its CX military transport plane during the next five months, said Yuko Ogino, a spokeswoman for Kobe-based Kawasaki Heavy.

The prototype of the CX will be delivered to the SDF on Wednesday.

A newspaper report earlier in the day said that Kawasaki Heavy plans to develop the civilian version of the CX by 2012 in what would be Japan's first such conversion.

The country is stepping up efforts to develop domestically built planes to catch up with North America and Europe, which dominate the global aviation market.

Mitsubishi Heavy Industries Ltd., Japan's biggest aerospace company, is developing a 70- to 90-seat regional passenger jet and will decide by March 2008 whether to proceed with commercial production.