And he's writing a web diary for CBBC Newsround.
In his latest instalment, he describes ship manoeuvres and how the marines stay fit.
Diary entry four
When you're in a ship like the Ark Royal you don't get the chance to see much daylight. There aren't many windows.
But today we were up on deck. The Navy is showing off its forces here in the Gulf.
Helicopters taking off, the other ships in the fleet cruising past. One, HMS Liverpool doing a fast 90 degree turn - I thought it was almost going to tip over.
There are almost 30 ships here in the Royal Navy's task force. If the politicians and generals decide to go to war, they say they'll be able to get Royal Marines onto land fast.
Every day the marines train. Not easy on the ship. But they do firing practice off the back. And if they get a chance in between the helicopters landing, they train on deck. A makeshift assault course has been set up. Press ups, running up and down the deck. Anything they can to stay fit.