Complex sentence: In 1954 the company offered a twin-engined design, the CL-303, to meet an American Airlines requirement; it was a high-wing design for 60 to 70 passengers but again the design failed to interest other carriers.
Split into simpler sentences: In 1954 the company offered a twin-engined design, the CL-303, to meet an American Airlines requirement. It was a high-wing design for 60 to 70 passengers but this design also failed to interest other carriers.