In 1960, the Piper Aztec was introduced, using two 250 hp (190 kW) Lycoming O-540 engines; Cessna too had improved its 310 with two Continental IO-470 D, producing 260 hp (190 kW). The first Baron included the fully-swept vertical stabilizer of the Debonair while still retaining the four to four+five place seating of the Travel Air.
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