Complex sentence: Construction of the first prototype's fuselage started in October 1945 in another hangar while a considerably larger assembly hall was built for final assembly and the runway was lengthened to 8,000 ft (2,440 m).
Split into simpler sentences: Construction of the first prototype's fuselage started in October 1945 in another hangar while a large assembly hall was built for final assembly. The runway was lengthened to 8,000 ft (2,440 m).