What can't you figure out? They move the same as walking on the ground, but you need to move to the cockpit room and hit the Enter Cockpit link before you can do that.
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
If it only has one room, that has to be the cockpit. Some have more, though. You might try going to Piloted Vehicles in your inventory, and make sure the vehicles is set to Player Controlled.
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
Y'know, it's been so long since I went to something that wasn't already set to it I'll have to look it up...
You need to go to Vehicles on your Inventory menu. Then go to Manage Piloted Vehicle at the top. Then there should be a checkbox next to the "Show stats" link for the vehicle. Check then, and make sure "Set Player Controlled" is in the dropdown menu. Then hit the Execute button.
At this point you should have an Enter Cockpit link under your normal Position link on the Control menu.
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
Like I mentioned, the vast majority of assets in the game are already set to player controlled, because someone's flown them beforehand, so people often forget about it. It's probably something that's worth adding the The Guide, though.
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
Mmm...
On Execute of Set Player Controlled I have "Error: Must Be on Board Vehicle First"... I'm at the same coordinates of the vehicle, am I missing something?