A plane may be compelled to land through the use, or threat of use, of force, if it strays off course into hostile foreign territory. The Chicago Convention on International Civil Aviation contains guidance in Annex 2 on "Signals for Use in the Event of Interception":[1] customarily for the military plane approaches the airliner from below and to the left, where his plane is easily visible from the left seat where the captain sits. The intercepting plane waggles his wings to signal the demand to be followed.[2]