Reciprocating engines
(a) Reciprocating engines. Each reciprocating engine air induction system must have means to prevent and eliminate icing. Unless this is done by other means, it must be shown that, in air free of visible moisture at a temperature of 30 F., each airplane with altitude engines using (1) Conventional venturi carburetors have a preheater that can provide a heat rise of 120 F. with the engine at 60 percent of maximum continuous power; or (2) Carburetors tending to reduce the probability of ice formation has a preheater that can provide a heat rise of 100 F. with the engine at 60 percent of maximum continuous power.