The 36A is an upgraded model of the 35. Over 600 of the 35 & 36 models were manafactured between 1976 and 1993. The Learjet 36A is essentially identical to the 35, except that it has a larger fuselage fuel tank, Giving it 500 miles longer range, but reducing the passenger area's length by 18 inches. The 36A has upgraded engines and a higher maximum gross weight and was introduced in 1976 repalcing the 36.