Uncle DaveO - Yes, there was a difference between the US Navy and the Royal Navy.

In the RN a Commadore was a tempory rank given to the Senior Officer of a squadron, who had executive powers over the rest of the squadron.

There were 2 classes of Commadore - The First Class had a Captain under him. ie He was responsible for the squadron only, and a sepperate officer had the comand of the Pennant ship.

The Second class comanded his own ship as well.

In the USN - Commadore was a permenant rank.

Gareth