Boeing is to make the newly developed multi-mode receiver (MMR) a basic feature on all its commercial aircraft. The company was expected to certificate the 757, the first type to be fitted with the system without an MMR, by the start of the year.

"We have decided to move to the MMR as a basic offering and we are also moving the GPS [global-positioning system] into it. MMR with GPS will be the only way to get it on the 757/767 soon," says CNS/ ATM (communications, navigation and surveillance/air-traffic management) projects manager David Allen. The first aircraft are fitted with Rockwell-Collins MMRs, although some later ones have been specified with a similar Sextant Avionique receiver.

The use of the MMR minimises the number of avionics boxes on the aircraft and fits in a space used by the instrument-landing system (ILS). "We'll get into that box again for differential GPS," says Allen. The 757 installation, which was certificated in test flights using an aircraft destined to be the first C-32A for the US Air Force, will be followed by the 767 "some time in the first quarter of 1998", pending availability of an aircraft.

Certification is closely tied to the future-air-navigation-system (FANS-1) development for all Boeing types. FANS-1 certification for the 757 is concurrent with the MMR, as it will be for the 767. Similarly, MD-90s and MD-11s bound for Saudi Arabian airlines will also have FANS certification as part of the applications in their Honeywell Pegasus flight-management-computer systems.

The 747-400, which has been certificated for the GPS (and the FANS-1) for some time, will be approved with the MMR by June. The certification will be for operation with the ILS only in its initial form, but will be extended to include the GPS from September, when Air New Zealand is due to take an aircraft equipped from new with the FANS-1. "The 777 will also be offered with the system as basic," adds Allen. The system is also certificated for ILS use only on the Next Generation 737 and will be expanded later to include the GPS, as will the current 737 family.

Almost 350 FANS packages have been sold and nearly 200 installed on 747-400s (65-75% of the fleet). The FANS will soon be certificated with the MMR on the 757 and 767. The 737 is offered with a partial FANS package, including required navigation performance, airline operational-communications datalink and the GPS, but not automatic dependent surveillance, or con- troller/pilot datalinks.

Source: Flight International