The plan for the bombardment of Tripoli

Admiral Cunningham proposed, as a compromise, to bombard Tripoli inconjunction with a convoy from Malta. This was accepted by the commanders in Britain. This became more palatable to them after Captain Mack's recent destruction of a convoy off Sfax with his destroyers. The impending need to evacuate troops from Greece was also a factor.

Tripoli was a mile square harbour enclosed by a breakwater. The town was a promontory that formed the western and northern border. The ship berths were on the northern breakwater. The southeast corner had a seaplane station. Admiral Cunningham proposed to bombard Tripoli in the early morning, before dawn. Aircraft from the aircraft carrier would drop flares to provide light for the shooting. The submarine Truant would shine a light and ping its sonar (ASDIC). The forces involved were:

The Bombarding Force:

Battleships

Warspite (Cunningham's flagship)
Barham
Valiant

Cruiser

Gloucester

and 9 destroyers

The Carrier Force:

Formidable
3 cruisers
4 destroyers

This is based on the account in Vol.II of the Official History.