Complex sentence: Similar designs were proposed by the SOCATA subsidiary of Aérospatiale (based on their TB 10 Tobago light aircraft) and by GEPAL (the GEPAL Mk II), and the SOCATA proposal, the TB 30B, was chosen in February 1979.
Split into simpler sentences: Similar designs were proposed by the SOCATA subsidiary of Aérospatiale (based on their TB 10 Tobago light aircraft) and by GEPAL (the GEPAL Mk II). The SOCATA proposal, the TB 30B, was chosen in February 1979.