6–A propulsion
Rudders, propellers, and struts
Materials
Bronze
Copper and tin alloy highly resistant to saltwater corrosion.
Carbon Fiber
Stiffer and greater strength-to-weight ratio compared to fiberglass, but less resistant to impacts.
Composite Sandwich
Closed-cell foam core between inner and outer fiberglass laminate.
Fiberglass
Lightweight, strong, and moldable.
Naval Brass
Copper and zinc alloy resistant to saltwater corrosion.
Stainless Steel
Higher corrosion resistance and strength than aluminum, but much heavier.
Turcite
Strong, self-lubricating, low-friction thermoplastic for bearings and bushings.