50 guns:
- Gundeck: 22 × 24 pdrs
- Upper gundeck: 22 × 12 pdrs
- Quarterdeck: 4 × 6 pdrs
- Forecastle: 2 × 6 pdrs
HMS Newcastle was a 50-gun fourth rate ship of the line of the Royal Navy, built at Portsmouth Dockyard to the draught specified in the 1745 Establishment, and launched on 4 December 1750.
Newcastle foundered during a cyclone in 1761.