Wet leasing by definition is when an airline gets airplanes and pilots from a second party.
Let's say the government asks Air Canada to transport, on short notice, hundreds of troops from one place in Canada to somewhere else. If Air Canada says that their airplanes are in maintenance and they don't have the airplanes, but they'll get some and they'll do the job, Air Canada will wet lease. They will get airplanes and pilots from somewhere else, and then use the Air Canada system to support that flying.