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FSDLP v1 FSDLP v1 Flight Simulation Data Link Protocol

List of Messages

Section titled “Uplink Messages”
ResponseDescription
W/U

Response Required with one of the following downlink messages:

  • DM0 — WILCO
  • DM1 — UNABLE
  • DM2 — STANDBY
  • DM62 — ERROR error information
  • DM63 — NOT CURRENT DATA AUTHORITY
  • DM107 — NOT AUTHORIZED NEXT DATA AUTHORITY
A/N

Response Required with one of the following downlink messages:

  • DM2 — STANDBY
  • DM4 — AFFIRM
  • DM5 — NEGATIVE
  • DM62 — ERROR error information
  • DM63 — NOT CURRENT DATA AUTHORITY
  • DM107 — NOT AUTHORIZED NEXT DATA AUTHORITY
R

Response Required with one of the following downlink messages:

  • DM1 — UNABLE
  • DM2 — STANDBY
  • DM3 — ROGER
  • DM62 — ERROR error information
  • DM63 — NOT CURRENT DATA AUTHORITY
  • DM107 — NOT AUTHORIZED NEXT DATA AUTHORITY
Y

Response Required with any downlink message

N

Response Not Required, but can be replied to with with one of the following downlink messages:

  • DM62 — ERROR error information
  • DM63 — NOT CURRENT DATA AUTHORITY
  • DM107 — NOT AUTHORIZED NEXT DATA AUTHORITY
NE

Response Not Required, and no repsonse should ever be sent

UM0

Section titled “UM0”

UNABLE N |

UM1

Section titled “UM1”

STANDBY N |

UM3

Section titled “UM3”

ROGER N |

UM4

Section titled “UM4”

AFFIRM N |

UM5

Section titled “UM5”

NEGATIVE N |

UM19

Section titled “UM19”

MAINTAIN altitude W/U |

UM20

Section titled “UM20”

CLIMB TO altitude W/U |

UM23

Section titled “UM23”

DESCEND TO altitude W/U |

UM26

Section titled “UM26”

CLIMB TO REACH altitude BY time W/U |

UM27

Section titled “UM27”

CLIMB TO REACH altitude BY position W/U |

UM28

Section titled “UM28”

DESCEND TO REACH altitude BY time W/U |

UM29

Section titled “UM29”

DESCEND TO REACH altitude BY position W/U |

UM30

Section titled “UM30”

MAINTAIN BLOCK altitude TO altitude W/U |

UM31

Section titled “UM31”

CLIMB TO AND MAINTAIN BLOCK altitude TO altitude W/U |

UM32

Section titled “UM32”

DESCEND TO AND MAINTAIN BLOCK altitude TO altitude W/U |

UM36

Section titled “UM36”

EXPEDITE CLIMB TO altitude W/U |

UM37

Section titled “UM37”

EXPEDITE DESCENT TO altitude W/U |

UM38

Section titled “UM38”

IMMEDIATELY CLIMB TO altitude W/U |

UM39

Section titled “UM39”

IMMEDIATELY DESCEND TO altitude W/U |

UM46

Section titled “UM46”

CROSS position AT altitude W/U |

UM47

Section titled “UM47”

CROSS position AT OR ABOVE altitude W/U |

UM48

Section titled “UM48”

CROSS position AT OR BELOW altitude W/U |

UM49

Section titled “UM49”

CROSS position AT AND MAINTAIN altitude W/U |

UM51

Section titled “UM51”

CROSS position AT time W/U |

UM52

Section titled “UM52”

CROSS position AT OR BEFORE time W/U |

UM53

Section titled “UM53”

CROSS position AT OR AFTER time W/U |

UM54

Section titled “UM54”

CROSS position BETWEEN time AND time W/U |

UM55

Section titled “UM55”

CROSS position AT speed W/U |

UM56

Section titled “UM56”

CROSS position AT OR LESS THAN speed W/U |

UM57

Section titled “UM57”

CROSS position AT OR GREATER THAN speed W/U |

UM61

Section titled “UM61”

CROSS position AT altitude AT speed W/U |

UM64

Section titled “UM64”

OFFSET distance direction OF ROUTE W/U |

UM72

Section titled “UM72”

RESUME OWN NAVIGATION W/U |

UM74

Section titled “UM74”

PROCEED DIRECT TO position W/U |

UM75

Section titled “UM75”

WHEN ABLE PROCEED DIRECT TO position W/U |

UM76

Section titled “UM76”

AT time PROCEED DIRECT TO position W/U |

UM77

Section titled “UM77”

AT position PROCEED DIRECT TO position W/U |

UM78

Section titled “UM78”

AT altitude PROCEED DIRECT TO position W/U |

UM79

Section titled “UM79”

CLEARED TO position VIA route clearance W/U |

UM80

Section titled “UM80”

CLEARED route clearance W/U |

UM81

Section titled “UM81”

CLEARED procedure W/U |

UM82

Section titled “UM82”

CLEARED TO DEVIATE UP TO distanceoffset direction OF ROUTE W/U |

UM83

Section titled “UM83”

AT position CLEARED route clearance W/U |

UM84

Section titled “UM84”

AT position CLEARED procedure W/U |

UM91

Section titled “UM91”

HOLD AT position MAINTAIN altitude INBOUND TRACK degrees direction TURN LEG TIME leg type W/U |

UM92

Section titled “UM92”

HOLD AT position AS PUBLISHED MAINTAIN altitude W/U |

UM93

Section titled “UM93”

EXPECT FURTHER CLEARANCE AT time R |

UM94

Section titled “UM94”

TURN direction HEADING degrees W/U |

UM96

Section titled “UM96”

CONTINUE PRESENT HEADING W/U |

UM106

Section titled “UM106”

MAINTAIN speed W/U |

UM107

Section titled “UM107”

MAINTAIN PRESENT SPEED W/U |

UM108

Section titled “UM108”

MAINTAIN speed OR GREATER W/U |

UM109

Section titled “UM109”

MAINTAIN speed OR LESS W/U |

UM116

Section titled “UM116”

RESUME NORMAL SPEED W/U |

UM117

Section titled “UM117”

CONTACT unit name frequency W/U |

UM120

Section titled “UM120”

MONITOR unit name frequency W/U |

UM123

Section titled “UM123”

SQUAWK beacon code W/U |

UM127

Section titled “UM127”

REPORT BACK ON ROUTE R |

UM134

Section titled “UM134”

CONFIRM SPEED NE |

UM135

Section titled “UM135”

CONFIRM ASSIGNED ALTITUDE NE |

UM137

Section titled “UM137”

CONFIRM ASSIGNED ROUTE NE |

UM148

Section titled “UM148”

WHEN CAN YOU ACCEPT altitude NE |

UM153

Section titled “UM153”

ALTIMETER altimeter R |

UM154

Section titled “UM154”

RADAR SERVICES TERMINATED R |

UM157

Section titled “UM157”

CHECK STUCK MICROPHONE frequency R |

UM159

Section titled “UM159”

ERROR error information N |

UM160

Section titled “UM160”

NEXT DATA AUTHORITY facility ident N |

UM161

Section titled “UM161”

END SERVICE N |

UM166

Section titled “UM166”

DUE TO TRAFFIC N |

UM167

Section titled “UM167”

DUE TO AIRSPACE RESTRICTION N |

UM179

Section titled “UM179”

SQUAWK IDENT W/U |

UM183

Section titled “UM183”

CURRENT ATC UNIT unit name N |

UM169

Section titled “UM169”

free text R |