The GPS system was originally developed by the US military to target missiles and guide troop movements but now has dozens of commercial applications from helping motorists find their way about to ships' navigation, search and rescue and road pricing.
This hardware was used to build a simulated aircraft that ran many of the systems found on commercial aircraft and could swap data via radio with the air traffic and navigation systems used in the real world.
The landowners had argued that a waterway must have a history of commercial use to be subject to common law, which says the public has the right to use it for navigation.