1. Findings and trends from the CoSpace / EVP series of flight deck experiments on ASAS spacing
Karim Zeghal EUROCONTROL Experimental Centre
ASAS-TN, April 2004, Toulouse

2. Motivation Motivation Constraints Assumptions
Identify a more effective allocation of spacing tasks between controller and flight crew
One option to improve air traffic management
Neither “transfer problems” nor “give more freedom” to pilots … shall be beneficial to all parties
Constraints
Human: consider current roles and working methods
System: keep things as simple as possible
Assumptions
Airborne surveillance capabilities (ADS-B, “state vectors”)
Airborne functions (ASAS, “manual mode”)

3. Principle Principles Expected benefits Two classes of operations
Use of spacing instructions (not separation not clearance) to be used with current practices
No modification of responsibility for separation provision
Flight crew tasked by the controller to maintain a given spacing to a designated aircraft
FAA/Eurocontrol PO-ASAS, ICAO SCRSP ASAS circular
Expected benefits
Increase of controller availability, leading to improve safety
… in turn: better traffic management and, depending on airspace constraints, more capacity
Gain in awareness and anticipation for flight crew
Two classes of operations
Crossing and passing
Sequencing of arrival flows

4. Stepwise validation Air & ground Operational Validation Technology
Two streams of experiments with unified perspective
Operational
Start in cruise (extended TMA) and progressively get closer to the runway (TMA)
Validation
Start assessing usability and progressively address impact on user activity and eventually on the ATC system
Technology
Start with a basic working environment and progressively introduce assistance and technology when need clearly identified

5. Stepwise validation air ground 1998 1999 2000 2001 2002 2003 CRZ-IAF
CRZ-FAF
air
IFATCA’98
Ext TMA
Enroute
ground
Ext TMA
Enroute
Ext TMA
Ext TMA
TMA
TMA
1998
1999
2000
2001
2002
2003

6. Starting point

7. From usability to activity

8. More assistance, more realism

9. Getting down to final with time

10. More complex scenarios

11. Stepwise validation air ground 1998 1999 2000 2001 2002 2003 CRZ-IAF
CRZ-FAF
air
IFATCA’98
Ext TMA
Enroute
ground
Ext TMA
Enroute
Ext TMA
Ext TMA
TMA
TMA
1998
1999
2000
2001
2002
2003

12. Experiment set-up Objective Environment Flight deck Flight crew
Extend the scope to the approach phase, with time based spacing
Environment
Paris South arrival flights, from cruise to final approach (~40 minutes flight time)
Recorded scenario including ATC instructions and background traffic
Target under conventional control
Flight deck
Flight crew tasks: automatic flight, checklist, operational flight plan, ATIS, briefing, and manual speed adjustments
Cockpit simulator: A320 FMGS trainer from FAROS
Flight crew
12 Airbus rated airline pilots
Exercises
Achieved: 24 runs in time, 6 in distance, 12 in conventional

13. Activity Ok

14. Spacing performance Average deviation well below tolerance
Maximum
4.6s
Average deviation well below tolerance
No loss of spacing
Average
0.9s

15. Findings Benefits Limits Issues
Positive feedback on concept (active part, being “in the loop”, understanding of the situation, more anticipation)
Spacing feasible (e.g. ±5s) until final approach, with limited assistance, at acceptable workload (under nominal conditions)
Limits
Where to end spacing on final (at FAF, before or later)?
Under which degraded situations (aircraft, meteo, …) spacing still feasible?
Issues
New task with potential risk of workload increase (appropriate level of assistance)
Preceding pilot behaviour? Risk of oscillatory effects?