MIT
ICAT
Airspace Resource Allocation
-Operations Impact
Prof. R. John Hansman, Director
MIT International Center for Air Transportation
rjhans@mit.edu 617-253-2271
MIT
ICAT

Preliminary Thoughts
Have not seen the political argument to justify the costs/pain of
transition
 What is the problem we are trying to solve
 What are the functional requirements
 Is this an issue which extends beyond LGA
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Current system is regulated by delay
 Schedule integrity, passenger tolerance
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Current system is complex, evolved and impedance matched
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Gates
Runways
Taxiways
Landside
Security
Arrival fixes
Departure fixes
Safety Concerns will drive Arguments to Resist
MIT
ICAT
What are the property rights that make
sense in the operating environment?
 Landing Slots (Perishable)
 Time Based
 Time scale (1min, 15 min, 1hr, 3hr, day)
 Sequence Based
 Priority
 What are the rights and responsibilities of property ownership
 Users
 Precision
 When do you loose the resource
 Provider (Safety) induced delays (who is responsible)
 Providers
 Guarantees
 Substitution
 Failure propagation
MIT
How do you set the resource limit?
ICAT
 VFR Capacity ?
 IFR Capacity ?
 With Margin ?
 Peak Capacity
 Airport “flush” modes
Runway Configuration Capacity
Envelops
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ICAT
R u n w a y C o n fig u ra tio n C a p a c ity E n v e lo p s
(S o u rc e : E T M S / T o w e r R e c o rd s , 7 -9 A M , 4 -8 P M , J u ly 1 -1 5
1 9 9 8 e x c e p t S a tu rd a y s , L o g a n A irp o rt)
Actual Arrival Rate (per 15 minutes)
25
4 L / 4 R -9 (re p o rt e d
20
a ve ra g e 6 8 A A R - 5 0
DE P )
2 7 / 2 2 L -2 2 R (re p o rt e d
15
a ve ra g e 6 0 A A R - 5 0
DE P )
3 3 L / 3 3 R -2 7 (re p o rt e d
10
a ve ra g e 4 4 A A R - 4 4
DE P )
S in g le R u n w a y (Ja n u a ry
5
1 9 9 9 , re p o rt e d a ve ra g e
34 A A R 34 DE P )
0
0
5
10
15
20
A c t u a l D e p a rt u re R a t e (p e r 1 5 m in u t e s )
25
MIT
ICAT
Variable Capacity Effects
1995 Delays vs Operations
Data from FAA Capac ity Offic e, CY95
60
SFO
Delayed Flights (per 1000)
50
40
LGA
STL
EWR
ORD
30
LAX
DFW
ATL
BOS
20
J FK
IAH
10
SJU
CLT
PIT
MEM
HNL
0
0
200000
400000
PHX
DEN
LAS
600000
800000
1000000
Total Operations (CY95)
From John Andrews, MIT Lincoln Lab
MIT
ICAT
From: Xavier Fron, Eurocontrol
MIT
ICAT
Robustness Issues
 Robustness Issues
 Flexibility to normal interruptions
 Convective Weather
 Go around
 Mechanicals
 Deicing
 Lack of Data
 Special Runway Requirements
 Non-Normal Ops
 How do you handle high priority non planned demand?
 Air Force 1
 “Lifeguard”
 How do you handle unplanned resource loss?
 Disabled Aircraft
 Blown Tire
 Snow Plow
MIT
ICAT
 May 3, 2001
Convective Weather Impact
6:20 p.m.
295 Aircraft In-bound
MIT
ICAT

Terminal Area Weather
Impact
Weather disrupting NW corner fix into
Chicago perturbs standard flow
abstraction.

Two responses observed:
 Standard flow abstraction for
aircraft traversing the weather
no longer available – aircraft
treated as “special cases.”
 Alternative standard flow
abstraction is used.
MIT
ICAT
Real Time Allocation Challenges
 Planning Time Horizons
 Weather time constants (< 30 min for convective)
 Airline response time constants (
 ATC Response
 Safety Constraints
 Acceptable Level of Traffic
 Wake Vortex
 Asymmetric Control
 Fast Shut Down
 Slow Start Up
 Airline Planning/Response issues
 Planning time constant
 (median 90 min)
 Disrupted Options
 Lack of consistent or clear objective function
 Inter Airline Units
MIT
ICAT
Identification of AOC dynamics
Timing of Flight Planning
100%
90%
Actual departure time
80%
Cumulative percentage
70%
Nominal Flight Plan
Complete 90 min prior to departure
60%
50%
Flight Planning Tools
eg, Wind Optimal Routing
40%
30%
Optimization Basis Rarely Presented
to Flight Crews
20%
10%
0%
-25
0
25
50
75
100
125
150
175
200
225
250
Minutes before actual departure time
Start of flight planning
End of flight planning - all flights
275
300
325
350
375
400
# samples = 4180
End of flight planning - flights with delay > 5 min.
Source: AOC computer transactional data from a major airline (March 1998)