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 PHARE Overview
 Experimental Flight Management System
 Ground Human Machine Interface
 Airborne Human Machine Interface
 PHARE Advanced Tools
 Operational Concepts
 PHARE Demonstrations
 Common Modular Simulator
 Experimental Design

Experimental Flight Management System (EFMS)

The Experimental Flight Management System was developed to demonstrate, in simulation and flight trials, the capabilities of an advanced flight management system to:
  • Predict 4D trajectories, taking into account possible ATC constraints and airline operating procedures;
  • Negotiate this ‘user preferred trajectory’ with ATC via data link;
  • Guide the aircraft to that trajectory in space and time.
There were significant links between the Experimental Flight Management System and Airborn Human Machine Interface (AHMI) projects, with the AHMI activity initially being part of the EFMS:
  Link to Airborne Human Machine Interface project
The Experimental Flight Management System project had two main phases:
  • Phase 1, split into Phase 1a for PHARE Demonstration 1, and Phase 1b for PHARE Demonstration 2;
  • Phase 2, a complete redesign for PHARE Demonstration 3.

Phase 1

For Phase 1, the EFMS software was developed at different sites by a mix of aeronautical and software engineers. It became essential that a team of experienced software engineers completed the software analysis and design of the system, and also integrated and tested the software modules produced by the partners.

Phase 2

For Phase 2, a redesign was necessary to meet the new requirement for two-crew operation, and also to produce a more robust system for PHARE Demonstration 3. New software for Phase 2 was developed by the integration team, whilst the research centres produced the algorithms (plus any software specific to their aircraft), and conducted system tests.


The PHARE airborne programme was highly successful. The Experimental Flight Management System, with its Airborne Human Machine Interface was used in three PHARE Demonstration programmes using three real aircraft and a flight simulator.
  • In PHARE Demonstration 1, the BAC 1-11 of NATS/DERA was flown by company test pilots.
  • In PHARE Demonstration 2, the VFW-614 of DLR (ATTAS) was flown by company test pilots.
  • In PHARE Demonstration 3, the Cessna Citation II of NLR and the BAC 1-11 of NATS/DERA were flown by company test pilots. In addition the Multi-Cockpit Simulator (based on a Boeing 747) of the EUROCONTROL Experimental Centre was flown by several airline pilots.
The concept of 4D navigation was demonstrated to be readily achievable: cross-track errors of less than 100 metres; height errors of less than 500 ft. in climb and descent; time errors less than 10 sec. in cruise and descent (and less than 5 sec. in TMA). The impressive performance of the 4D guidance was, however, dependent on the accuracy of the forecast meteo data.

In PHARE Demonstration 2 the ability of an aircraft to fly negotiated trajectories in a routine manner while operating on its inbound route down to the approach gate within continuous 4D tolerances, was convincingly demonstrated.

For further information

The Experimental Flight Management System is documented in the following:
  Acrobat 97-70-07 PD/3 AHMI User Requirements Document60 Kb
  Acrobat 97-70-09 Prediction of Optimal 4D Trajectories in the Presence of Time and Altitude Constraints394 Kb
  Acrobat 98-70-13 PD/3 Airborne Evaluation Pilot Briefing Guide816 Kb
  Acrobat 98-70-19 Airborne Report2,558 Kb
  Acrobat 99-70-09 PHARE Final Report1,482 Kb
The results of the use of the Experimental Flight Management System in PHARE is described in the following:
  Acrobat 95-70-09 PD/3 Demonstration Facility Specification318 Kb
  Acrobat 96-70-24 PD1 Final Report Volume 2 Annex E Airborne Aspects of PD/11,514 Kb
  Acrobat 97-70-04 PD/3 Operational Scenarios Document (Volume 1)279 Kb
  Acrobat 97-70-08 PD/3 Operational Scenarios Document (Volume 2)303 Kb
  Acrobat 97-70-13 PD/2 Final Report Volume 2 Annex F Airborne Aspects of PD/2800 Kb
  Acrobat 99-70-01 Volume 1 of PD/3 Final Report - PHARE Demonstration 3 (PD/3) Synthesis Report204 Kb
  Acrobat 99-70-01 Volume 2 of PD/3 Final Report - CENA PD/3 Final Report Annex E Airborne Aspects886 Kb
The relationship between the Experimental Flight Management System and the Trajectory Predictor tool of the PHARE Advanced Tools set is discussed in the following:
  Acrobat 98-70-18 PATs Project Final Report Volume 10 Trajectory Predictor160 Kb
The air/ground negotiation process involving the Experimental Flight Management System is described in:
  Acrobat 95-70-03 PHARE: Air-Ground Data Exchange Study, S3190 Kb
  Acrobat 98-70-18 PATs Project Final Report Volume 7 Negotiation Manager203 Kb