Possible Clues:

• Board rescue vessel after English doctor
• Go on with me up the pub: The King's Head
• Take a look on the Titanic, for instance, for amber fluid found with potassium
• Board eastern rescue vessel, holding medical degree
• Board a ship or aircraft
• Set out (on an enterprise)
• Book into space ship and board
• Baker bakes first of muffins inside to put on board
• Join ship
• Go aboard old ship after half them British