Three times a day, a Gulfstream GIV has been quietly slipping out of Le Bourget to demonstrate the future of automated approach and landing technology. The aircraft is equipped with a Honeywell/Pelorus SLS 2000 satellite landing system which guides the aircraft into land using the GPS satellite system.
Experts will realise that GPS isn't accurate enough to do this, so the signals are being helped or "augmented" by another local ground-based signal. This comes from a SLS 2000 ground reference station that has been setup at Le Bourget for the demonstration.
Honeywell is part of a consortium of avionics manufacturers and US airports which is backing the use of GPS technology for precision landings, and is working with the US Federal Aviation Administration to create the specifications and standards needed for the future system.
Source: Flight Daily News