• New Output Capabilities

• Enhanced Taxiway Movement Logic

• Gate Pushback / Powerback Flexibility

• Enhanced Gate Selection

• Improved Runway Exit Logic

ContentsContents

1

New Output CapabilitiesNew Output Capabilities Background

Simulation RUN History

The size of the SIMU26 file may sometimes become too big for quick and easy extraction of useful data for reports

SIMMOD 2.3.1:

SIMU26NI,0. ,1 IN,.0001000,1,0,UAL384#0,384.1_GORD.SFO,0,535,GNDACTAB,.0001000,1,0IN,.0001000,2,0,NWA311#0,311.1_GMSP.SFO,0,532,GNDACTAB,.0001000,2,0IN,.0001000,3,0,UAL383#0,383.1_GIAD.SFO,0,544,GNDACTAB,.0001000,3,0IN,.0001000,4,0,TWA375#0,375.1_GSTL.SFO,0,544,GNDACTAB,.0001000,4,0IN,.0001000,5,0,AAL1#0,1.1_GORD.SFO,0,532,GNDACTAB,.0001000,5,0IN,.0001000,6,0,DAL145#0,145.1_GATL.SFO,0,535,GNDACTAB,.0001000,6,0IN,.0001000,7,0,GCO213#0,213.1_GLAX.SFO,0,526,GNDACTEJ,.0800000,12,0,?

~10 MB

ANIMATION

1 1 NM 9 145 A .9400000 .0358920 0.01 1 NM 8 143 A .9758920 .1136270 0.01 1 HA 7 -1 A 1.0895190 0.0 .08556231 1 NM 7 140 A 1.1750813 .0385706 0.01 1 HW 4 -1 A 1.2136519 0.0 .00108371 1 NM 4 138 A 1.2147355 .0147924 0.01 1 NM 12 137 A 1.2295279 .0127991 0.01 1 NM 1 136 A 1.2423270 .0298450 0.01 1 RL 1 78 D 1.2721720 .0032452 0.01 1 RL 2 20 D 1.2754171 .0133227 0.01 1 RL 3 20 D 1.2887398 .0123846 0.01 1 RL 4 20 D 1.3011244 .0077764 0.01 1 RL 26 20 D 1.3089008 .0071098 0.0

REPORTS

~5 MB

2

SIMU26 data are recorded at the start of the delay and contain the engine’s estimate of the delay end time

New Output CapabilitiesNew Output Capabilities Implementation

SOLUTION: Create another file for reports

TRACE 303 SIMU44 Runway records

Runway Crossing records

Add’l RWY Crossing records for intersecting runways

Departure Queue records

Gate records

Wheel records

Deicing records

Route records

Item CodeIteration NumberAircraft NumberItem IDEvent / Item ParametersSimulation time InSimulation Time Out

SIMU44 FORMAT:

Same delimiter as for SIMU26

3

Data output occurs at the end of the delay, thus the actual simulation time is reported

New Output CapabilitiesNew Output Capabilities Implementation

Item Code Convention.

RR refers to situations where a runway crossing intersects another runway. The RWY name in the record corresponds to the name of the RWY that this RWY Crossing intersects.

WH means Wheels ON if it precedes the RW record and Wheels OFF if it follows the RW record with the same Aircraft number. Item Parameter is another way to tell ON from OFF

RC is generated each time an AC exits RWY Crossing. Its time includes the entire time spent there, including all hold and engine spoolup times

CommentsIteration Number NI

Runway RW

Runway Crossing RC

Add'l RWY Crossing for Intersected runways

RR

Departure Queue DQ

Gate GE

Wheels On / Off WH

Departure Staging DS

Deicing DI

Route RE

4

New Output CapabilitiesNew Output Capabilities Example

SIMU26NI,0. ,1 IN,.0001000,1,0,UAL384#0,384.1_GORD.SFO,0,535,GNDACTAB,.0001000,1,0IN,.0001000,2,0,NWA311#0,311.1_GMSP.SFO,0,532,GNDACTAB,.0001000,2,0IN,.0001000,3,0,UAL383#0,383.1_GIAD.SFO,0,544,GNDACTAB,.0001000,3,0IN,.0001000,4,0,TWA375#0,375.1_GSTL.SFO,0,544,GNDACTAB,.0001000,4,0IN,.0001000,5,0,AAL1#0,1.1_GORD.SFO,0,532,GNDACTAB,.0001000,5,0IN,.0001000,6,0,DAL145#0,145.1_GATL.SFO,0,535,GNDACTAB,.0001000,6,0IN,.0001000,7,0,GCO213#0,213.1_GLAX.SFO,0,526,GNDACTEJ,.0800000,12,0,?

~9.5 MB

NI,0.0,1

GE,1,12,GTE_A10,D,.0800000,.0800000

GE,1,25,GTE_D4,D,.1667000,.1667000

GE,1,33,GTE_B10,D,.2500000,.2500000

DQ,1,33,DAPT_01L_APT,.3069993,.3069993

GE,1,42,GTE_G2,D,.3173720,.3173720

RW,1,33,01L,D,.3069993,.3181726

WH,1,33,OFF,.3075505

RE,1,33,DAPT_01L_SW,19,.3181726,.4088987 RC,1,6,28L_D,1.0994327,1.1250320, .0327311

RR,1,6,28L_D,28L,1.0994327,1.1250320, .0327311

SIMU44

~ 0.82 MB

Data for reports are now contained in a much smaller (an order of magnitude) and

more manageable file

SPECIAL HANDLING:SIMU44 will be written only if TRACE 303 is set ON

SIMU44 can only be used forDelay Reports

5

Enhanced Taxiway Movement LogicEnhanced Taxiway Movement Logic Background

In Figure 1, AC2 may have a higher ground link speed on GL_2 than AC1has on GL_1. If the airfield layout is such that the wingspan of either or both aircraft would not allow passing, there is no method to prevent AC2 from arriving at GN_4 earlier thanAC1 arrives at GN_2.

EXAMPLE:

This is a simple example of a class of situations where a different approach to taxiway movement logic would be appropriate

FIGURE 1:

AC 1

AC 2GL_1

GL_2

GN_2

GN_4

GN_3

GN_1

6

Implementation

Enhanced Taxiway Movement LogicEnhanced Taxiway Movement Logic

GroundLink - GroundLink BLOCKING:

AC2 @ GN_3?

AC 1

AC 2GL_1

GL_2GN_2

GN_4

GN_3

GN_1

GL_1 may block

GL_2?

yes

AC1 on GL_1?yes

AC1 will block

AC2 on GL_2?

yes

HOLD AC2 @ GN_3until AC1 is @ GN_2

yes

Proceed AC1 on GL_1

no no

no

FIGURE 2:

STOP

( This logic will workfor parallel, opposite,

intersecting, etc. ground links. )

7

SPECIAL CARE:

If AC1 is at GN_1 and AC2 is on GL_2 (see Figure 3), then, unless Reversible Blocking Flag is “T”, AC1 will go ahead

Implementation

Enhanced Taxiway Movement LogicEnhanced Taxiway Movement Logic

SIMMOD inputs:

New table in SIMU07: AFLINKBLOCKINGIt will include:

Reversible Blocking flag (T or F)

AFLink1

AFLink2

Mdl1

Mdl2

AC Model MDL1 on AFLink1

AC Model MDL2 on AFLink2

AC 1

AC 2

GL_1

GL_2

GN_2

GN_4

GN_3

GN_1FIGURE 3:

8

Implementation

Enhanced Taxiway Movement LogicEnhanced Taxiway Movement Logic

TABLE FORMAT:

AFLINKBLOCKING com NumGrps com NumMdlsNum ; AFLinkList1 ; AFLinkList2 ; MdlKyWd Mdl1 ; Mdl2 ; RevBlkFlg (and so on for the additional records)

AFLinkList1 First (blocking) list of Ground Links

AFLinkList2 Second (being blocked) list of Ground Links

MdlKyWd AC Model vs. Ground Group flag (“MDL” or “GRP”)

Mdl1 AC Model or ground group, respectively, blocking while on AFLink1

Mdl2 AC Model or ground group, respectively, being blocked while on AFLink2

RevBlkFlg Indicator = “T” if blocking is reversible, “F” otherwise

9

Background

SIMMOD 2.3.1:

This is a good approach to gate pushback / powerback, but it lacks some flexibility.

Gate Pushback/Powerback FlexibilityGate Pushback/Powerback Flexibility

PPBACK table in SIMU07 file

Lists models that only allow Pushback

PPTIME table in SIMU07 file

Lists Pushback & Powerback time distributions for AC ground groups from TAMPS table

GATES table in SIMU07 file

Gate type info referring to Pushback & Powerback (0, 1, or 2)

Sometimes it is necessary to allow different pushback

time distribution for a certain AC Model, even if it

belongs to a ground group listed in PPTIME table

10

New table in SIMU07:GATE_MDL_PP_TIMEIt will include:

Implementation

• Gate Identifier• List of Ground Links connected to the gate for which power/pushback is allowed• List of AC models for which push and powerback times are presented by the distributions

• Gate Identifier• List of Ground Links connected to the gate for which power/pushback is allowed• List of AC models for which push and powerback times are presented by the distributions

• Powerback Time distribution• Pushback Time distribution

• Powerback Time distribution• Pushback Time distribution

Figure 1

GTE_1(gate type 1 or 2)

GL_1

ACMDL1ACMDL2ACMDL3

GL_2ACMDL3ACMDL5

GL_3

Gate Pushback/Powerback FlexibilityGate Pushback/Powerback Flexibility

11

ImplementationGate Pushback/Powerback FlexibilityGate Pushback/Powerback Flexibility

Gate Type = 0?

Do NOT model PPBACK

yes

Gate Type = 1?

PUSH BACK

yesno

AC Model listed in PPBACK

?

no

yes

POWER BACKno

AC Model, Gate, AFLinklisted in GATE_MDL_PP_TIME

?Use time distribution from

GATE_MDL_PP_TIME

Use time distribution fromPPTIME

no

yes

12

SPECIAL CARE:If the gate type is 2 (powerback unless the AC is push back only),the powerback distribution in GATE_MDL_PP_TIME will NOT be used if the model is listed in PPBACK. (in Example 1, only pushback will always be used for model 48 coming out of gate 1 along link 15 or link 26.)

GATE_MDL_PP_TIME maximum 2 records1 15 26 ; gate1 GL15 GL26 1 2 15 48 ; MDL1 MDL2 MDL15 MDL48 0.0 10.0 1.0 13.0 ; Powerback time distribution 0.0 12.0 0.97 14.0 1.0 15.5 ; Pushback time distribution1 15 26 ; gate1 GL15 GL26 49 50 ; MDL49 MDL50 0.0 10.0 1.0 13.0 ; Powerback time distribution 0.0 12.0 0.5 14.0 1.0 15.0 ; Pushback time distribution

EXAMPLE 1PPBACK48

PPBACK48

PPTIME1 ; GRG1 0.0 9.7 0.01 10.0 1.0 13.0 ; Powerback time distribution 0.0 11.5 0.2 12.0 0.5 14.0 1.0 15.0 ; Pushback time distribution

PPTIME1 ; GRG1 0.0 9.7 0.01 10.0 1.0 13.0 ; Powerback time distribution 0.0 11.5 0.2 12.0 0.5 14.0 1.0 15.0 ; Pushback time distribution

ImplementationGate Pushback/Powerback FlexibilityGate Pushback/Powerback Flexibility

13

Example 1 (Cont.)Gate Pushback/Powerback FlexibilityGate Pushback/Powerback Flexibility

Figure 2

GTE_1GL_26

ACMDL48ACMDL49ACMDL50ACMDL1ACMDL2ACMDL15

GL_15GL_4

ACMDL48ACMDL49ACMDL50ACMDL1ACMDL2ACMDL15

GL_137ACMDL48ACMDL49ACMDL50ACMDL1ACMDL2ACMDL15

Only GL_15 and GL_26 are listed in the GATE_MDL_PP_TIME

table; for GL_137, PPTIME distribution will be used

14

Gate Selection LogicGate Selection Logic Background

SIMMOD 2.3.1:

This is a good approach to gate selection; but sometimes other considerations may force the analyst to need a different approach

Runway

GTE_5

GTE_4

GTE_2

GTE_1

GTE_3

yes

Go to it

Select a random gate among adequate, based

on its availability &“popularity” w /airlines

Select a random gate among adequate, based

on its availability &“popularity” w /airlines

Gate Assigned

?no

Gate Available

?

yes

no

Assign a different airline @ random

(subj. to constraints)Alternative

gate available?

yesno

9 AL

9 AL

GTE_5 has an 80% chance of being selected; GTE_1 has 20%

12 AL

12 AL

12 AL1 space

4 spaces

Figure 1

EXAMPLE 1:

1

1

15

Gate Selection LogicGate Selection Logic

SIMMOD inputs controlling gate selection logic:New table in SIMU07:AL_MDL_GATE_CHOICEIt will include:

Implementation

• Airline Identifier• List of AC models that this entry covers

• Airline Identifier• List of AC models that this entry covers

• Prioritized grouping of gates and respective preference distribution within each group

• Prioritized grouping of gates and respective preference distribution within each group

GTE_5

GTE_4GTE_2

GTE_1

GTE_3

Figure 2 If AL1 prefers GTE_3, but GTE_3 is also assigned to 11 other airlines, while GTE_1 is assigned only to AL1, GTE_3 has virtually no chance

of being selected, unless GTE_1 has no space.

Airline’s preferences need to be accommodated.

16

Gate Selection LogicGate Selection Logic Implementation

Airline Identifier SIMMOD number of the airline

List of AC Models Space delimited listing of aircraft models covered by this entry

Prioritized grouping of Gates

Group of gates to be considered first, second, etc. The gates are to be listed in the respective preference distribution.

AL_MDL_GATE_CHOICE com MaxNumber comArln1 MdlList1; com MaxGteGroups com Distr1Num Priority1GateDistr ; Distr2Num Priority2GateDistr ; (and so on in the decreasing order of priorities)

AL_MDL_GATE_CHOICE com MaxNumber comArln1 MdlList1; com MaxGteGroups com Distr1Num Priority1GateDistr ; Distr2Num Priority2GateDistr ; (and so on in the decreasing order of priorities)

17

Gate Selection LogicGate Selection Logic Implementation

SPECIAL CARE:This table has effect only when the airline is assigned and the gate is not available.

For the airlines and models listed in it, this table has priority over the standard gate selection logic.

DO NOT list a model more than once for each airline

GTE_5

GTE_4GTE_2

GTE_1

GTE_3

Figure 3

The situation described in Slide 2 (Figure 2) can be fixed as follows:

AL_MDL_GATE_CHOICE maximum 2 records1 15 26 115 230 ; 2 1 0.01 1 1.0 3 ; 2 0.01 2 0.97 4 1.0 5 ;1 25 30 24 17 ; 1 priority group 1 0.07 5 0.21 1 1.0 3 ;

EXAMPLE 2:

Spacei

( Spacej )*Pi = Pi

assigned

18

21%

33%

46%GTE_5

GTE_1

GTE_3

5

4

1

0

1

2

3

4

5

6

GTE_5 GTE_1 GTE_3

50%

40%

10%

GTE_5

GTE_1

GTE_3

7%

14%

79%

GTE_5

GTE_1

GTE_3

Gate Selection LogicGate Selection Logic

EXAMPLE 3:

As for any independent random events, the probability of a gate being selected is the (normalized) product of assigned and space-based probabilities

Assigned distribution

Final distribution Space-based distribution

Space at the gate

Implementation

19

Runway Exit LogicRunway Exit Logic Background

If an arrival aircraft is heading for GTE_1, but its minimum landing roll length is greater than the distance from touchdown at GRN1 to GRN2, it will take the next possible exit link # 123. In this case, the AC will then take link 1415RC and only then is it on the proper side of the runway.

EXAMPLE:

This is a simple example of a class of situations where a different approach to runway exit would be advantageous

Exit link 16 would have been the logical choice...

Figure 1

GTE_2

GTE_1 Runway

121

122

12315124

16 GRN2

GRN9RC

GRN3

GRN1

Min Roll

38

14

20

Runway Exit LogicRunway Exit Logic

SIMMOD inputs controlling runway exit operations

New table in SIMU07:RWY_GATE_ACMDLIt will include:

Implementation

• Runway Identifier• Destination Flag • Destination Identifier• List of AC models that this entry covers

• Runway Identifier• Destination Flag • Destination Identifier• List of AC models that this entry covers

• A way to indicate links to take and / or not

• A way to indicate links to take and / or not

GTE_2

GTE_1 Runway

121

122

123

Figure 1

15124

16 GRN2

GRN9 RCGRN3

GRN1

Min Roll

38

14

21

Runway Exit LogicRunway Exit Logic Implementation

Runway Identifier Name of the runway either in primary or opposite direction; the logic will work for both directions of the runway

Destination Identifier Concourse number or Gate number from SIMU07

List of AC Models Space delimited listing of aircraft models covered by this entry

A way to indicate exit links for aircraft of model from the list going to the gate or concourse on the runway:

List of PROHIBITED exit links

List of PROHIBITED exit links

Distribution of ALLOWED exit links

Distribution of ALLOWED exit links

22

Destination Flag An indicator = “G” if the record is for a gate= “C” if the record is for a concourse

Runway Exit LogicRunway Exit Logic Implementation

Distribution of ALLOWED exit links

In this case, the engine will sample from the distribution, and

the selected link will be the one to be taken, unless it is listed

as prohibited for this AC model / gate / runway.

List of PROHIBITED exit links

In this case, the engine will proceed the usual way, with the exception that it will check the exit link for being in list of prohibited exit links. If it is, then the engine will select the next non-prohibited exit.

SPECIAL CARE:If the final runway exit link is prohibited, the engine may terminate with an error, if no other exit link is feasible.

If the randomly picked exit is listed as prohibited for this

AC model / gate / runway, then the sampling will continue

until a non-prohibited exit is found.

23

Runway Exit LogicRunway Exit Logic Implementation

TABLE FORMAT: List of Prohibited links

TABLE RULES:

1 Either Distribution or Prohibited Links in each record2 If Distribution, then MaxNumProhib = 03 If a link is listed with non-zero probability in one record but is prohibited in another, then another link will be randomly picked until a non-prohibited link is selected.

TABLE FORMAT: Distribution of Allowed Links

RWY_GATE_ACMDL_P com MaxNumNum RwyName ; GCFlag GateNum; MdlList ; MaxNumProhib ProhibExitLnkList ; com(and so on for additional records)

RWY_GATE_ACMDL_D com MaxNumNum RwyName ; GCFlag GateNum; MdlList ; MaxNumProhib ExitLnkDst ; com (and so on for additional records)

24

Runway Exit LogicRunway Exit Logic

RWY_GATE_ACMDL_P Maximum Number: 1 1 APT_01L ; G 1 ; 114 115 116 117 ; 1 123 ;

RWY_GATE_ACMDL_D Maximum Number: 1 1 APT_01L ; G 1 ; 114 115 116 117 ; 0 0.02 124 1.0 16 ;

In either case, link 123 will not be taken, and the aircraft will proceed to link 16 or to link 124.

In this case, even if links 124 and 15 are parts of the taxipath for this ARRIVAL event, once 16 has been selected, it will be taken.

GTE_2

GTE_1 RunwayAPT_01L

121

122

123

Figure 1

15124

16 GRN2

GRN9RC

GRN3GRN1

Min Roll

38

14

25