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Controllers Guide - CDM

ThisA guideone-page coversquick howreference for BIRD controllerscontrollers. runEach departuressection with the CDM plugin and handle slots (CTOTs) issued by vIFF. It applies to BIKF, BIRK, BIAR, EKVG, BGGH and BGSF.

  • CDM sequences start-up locally. From each TOBT it calculates a TSAT (start-up time) and TTOT (take-off time) using the airport's departure rate.
  • vIFF is the network flow system. It issues CTOTs when an airport, a Traffic Volume or an ECFMP measure is over capacity. CTOTs exist whether or not CDM is running.

The BIRD install pack runs CDM with real mode off. The filed EOBT is never copied into the TOBT, so a flight has no TOBT, TSAT or TTOT until the pilot sets one on the VDGS or DEL sets it. Getting the TOBT is part of every clearance.

The times

TimeMeaningSet by
EOBTOff-block time filed in the flight planPilot
TOBTWhen the aircraft will really be ready to pushPilot (VDGS) or DEL
TSATWhen start-up will be approvedPlugin
TTOTTSAT plus taxi timePlugin
ASRTWhen the pilot called ready (RSTUP)DEL/GND
CTOTSlot from vIFF, or a manual slotvIFF or CDM master
CTOCThe CTOT passedlinks to the pilot,full and how far the live CTOT has moved sinceDEL
  • TSAT is valid ±5 minutes.
  • CTOT is valid -5/+10 minutes.
  • No ASRT/RSTUP by TOBT+5: the plugin cancels the TSAT and a new TOBT is needed.
page.

Before youand connectduring your session

  1. Use the current BIRD install pack. It includes CDM.dll, CDMconfig.xml, rate.txt and taxizones.txt. Do not replace these files with your own.
  2. Make sure the CDM plugin is loaded and allowed on your display (OTHER SET → Plug-ins).
  3. Use the departure list from the profile, with the CDM columns: EOBT, TOBT, TSAT, ASRT, RSTUP, TTOT, CTOT, CTOC, NSTS and Flow Message.
  4. Book your positionposition. onvIFF the VATSIM booking system. vIFFcapacity scenarios only see bookings, not who is online.bookings.

Starting a session

The lowest position at the airport is

  • CDM master: DEL, otherwise GND, otherwise TWR or the top-down controller. Everyone else runs as slave.

    1. Select the active departure runways in the Runwayrunway dialog. With no runway selected, CDM calculates nothing.
    2. TypeLowest .cdmposition masterbecomes BIKF (or your airport's ICAO).
    3. Check the CDM panel (.cdm panel): greenmaster: = you are master, purple = someone else is (coordinate first), red = no master.
    4. Times update every 10 seconds. If they do not appear, type .cdm refresh.

    Handover and logging off

    1. Outgoing master types .cdm slave.
    2. Incoming controller types .cdm master BIKF.
    3. AfterHand aover EuroScope crash, reconnect and typewith .cdm recover BIKFslave. → Starting CDM & handing over master

    DeliveryThe rules

    1. On
      2. firstcontact,
    2. TOBT
      3. RuleWindow
      No checkTOBT means no TSAT (real mode is off)Get the TOBT column:at
        clearance
      Pilot setmust oncall readyBy TOBT+5, or the VDGStimes are cancelled
      Start-up approvalTSAT ±5
      Take-off with a slotCTOT -5/+10. Always followed.

      Each departure

      frequency."

      1435,early.
    3. If
      4. an
      StepWhoActionSay
      1. ClearanceDELCheck TOBT; if missing, ask and still valid: use it.
    4. No TOBT, or clearly wrong: ask for one, then enter it with TOBT Options → Edit TOBT.
    5. Click Pilot ready now:TSAC useafter Ready TOBT. This sets TOBT to now and asks vIFF for a better slot (REA).
    6. Wait for TSAT and TTOT to appear (up to 10 seconds).
    7. Check the CTOT column. If there is a CTOT, the Flow Message shows the regulation causing it.
    8. Give the clearance, ending withgiving the start-up time and the slot time if there is one.
    9. If there is a CTOT, click CTOC → Add CTOT to CTOC to record what you passed to the pilot.
    10. When the pilot calls ready, click RSTUP, then transfer to Ground within TSAT ±5.

      11. Phraseology

      No TOBT:

      DEL: time.

      		"ICE123, reportReport your target off-block time."
      Pilot:… "Target off-block 1420, ICE123."

      If the pilot does not know the term: "ICE123, when will you be ready to push back?"

      Clearance, no CTOT:

      "ICE123, cleared to London Heathrow via DELES2C departure, runway 19, squawk 2341. Start-up time 1425, call ready for start-up."

      Clearance with CTOT:

      "ICE123, cleared to London Heathrow via DELES2C departure, runway 19, squawk 2341. Slot time1450, 1450,expect start-up timeat 1435, call ready for start-up."

      2.

      Ready call

      		DEL/GNDClick ASRT. Ready early or no TOBT: Ready tooTOBT.Early: early:

      "ICE123,Expect start-up timeat 1435, standcall byback onat this1430."

      3.

      Transfer:

      "ICE123, contact Keflavík Ground 121.900."

      During events with a slot file, the slot appears in the EvSlot column. Click Add Event CTOT as MAN CTOT to apply it.

      Ground

      1. Approve push and start within Start-up
      		GNDTSAT ±5,dark andgreen: approve, set the ground status so ASAT is recorded.
    11. Pilot calls before TSAT-5: STUP/PUSH.
      		12. "start-Start-up timeapproved."
      4. stand by."
    12. Pilot calls after TSAT+5 with no RSTUP: send them back to Delivery for a new TOBT.
    13. Taxi
      		14. GNDWith a CTOT,slot, time the taxi so the aircraft reachesreach the holding point inside the window."... Your slot window,is not1450."
      5.

      Tower

      1. Take-off
      		TWRWithin must be within CTOT -5/+10.10; Checknot themore CTOTthan column5 beforeminutes line-up.early.
      MDI
    14. During radar release periods, get an APP release for each departure before take-off clearance.
    phraseology

    MissedWhen slotsthings go wrong

    SituationProblemAction
    WillTSAT miss by a few minutes, flight plan activeblankCTOTReady OptionsTOBT →if EXTENDthe (+10pilot minutes,is onceready; only)otherwise ask them to update the TOBT
    Will miss slot by up to 10 minCTOT options → EXTEND (once)
    Will miss slot by moreSendReady TOBT or REA (Network Sts) for a new slot; coordinate with DELslot
    ManualSlot changed"Revised slotCDM master sets a new manual CTOT..."
    CTOCTimes turnsstuck redor missingThe.cdm liverefresh CTOT→ isCDM moresetup than& 5 minutes later than the one given. Pass the new slot to the pilot.troubleshooting

    Where slots come from

    • BIRD scenarios: switched on automatically from VATSIM bookings, posted in the vIFF #flow-log channel.
    • Destination arrival rates: when the destination is over capacity.
    • ECFMP measures: per-hour, MDI and ADI measures are included automatically.
    • Manual CTOT: CTOT Options → Set/Remove MANUAL CTOT. Only accepted when the TSAT is more than 5 minutes away.
    BookedScenarioBIKF ARR/hrBIKF DEP/hrApproach entries/hrApproach occupancy
    BIKF APP onlyBI-BIKFTD1010206
    BIKF APP + TWR, no CTRBI-APPONLY14163010
    BIKF APP + any BIRD CTRBI-APPENR14163010
    Any BIRD CTR, no BIKF APPBI-ENRONLY1010206

    Useful commands

    CommandUse
    .cdm master BIKF / .cdm slaveTake or release CDM master
    .cdm refreshForce a recalculation
    .cdm lvoSwitch to the low-visibility departure rate
    .cdm startupdelay BIKF/19 1900Hold all TSATs on a runway until 1900 (9999 clears it)
    .cdm departuredelay BIKF/19 1900Hold all TTOTs on a runway until 1900 (9999 clears it)
    .cdm recover BIKFRestore times after a crash
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