Complex sentence: Most production aircraft were built in Germany, the first German built aircraft taking flight on 17 October 1956,50 more were manufactured in Spain by Construcciones Aeronáuticas SA as the CASA-127.
Split into simpler sentences: Most production aircraft were built in Germany, the first taking flight on 17 October 1956. The remainder (50) were manufactured in Spain by Construcciones Aeronáuticas SA as the CASA-127.