GPS - AN AIRLINE USERS VIEW

This paper is intended to provide an operator's view of the impact of GPS On the air transport industry. The discussion centres on use of GP S for the en-route, oceanic, terminal area and precision approach phas es of flight. In summary the author suggests the following: (i) Ineffi cient use of airspace is costing the airlines a huge amount of money. However, GPS is not a pre-requisite of a move towards more efficient u se of that airspace, although it will be required as part of the event ual CNS/ATM package. In the near term, better usage of current equipme nt such as IRS and DME, together with the introduction of ADS can prov ide the required level of accuracy for reduced separation in en-route and oceanic airspace. (ii) There is a real need to provide navigation for non-precision approach worldwide, independent of ground-based infr astructure. This is the area in which GPS can provide the most immedia te improvement to safety. (iii) There are still a large number of ques tions hanging over GPS for precision approach. This leads the author t o believe that it will not be capable of replacing ILS for the more cr itical Cat 2 and 3 applications quickly enough to avoid the loss of th ese capabilities in some critical locations. For this reason, it is po stulated that MLS will be required in Europe, at least. Even if MLS is not required, there will still need to be a means of dealing with the transition away from ILS and for this reason the concept of a multi-m ode receiver has been developed.