All c/n's delivered to the RAN where B models, as noted by T53-L11 power plants, China weights on the rotor head, and narrow cord rotor blades. C models had T53-L13 power plants, 540 series rotors (no china weight and large cord rotor blades), and larger fuel tanks (filler high on the left side). N9-3102 and N9-3104 did have C model fuel tanks. It should also be noted that all RAN UH-1's had E model external cabin winches, but this did not make them UH-1E's.