TBL 5 − 3 − 11 Emergency/Urgency Downlink Message Elements (EMGD) TBL 5 − 3 − 12 Standard Response Uplink Message Elements (RSPU) CPDLC Message Sets Operational Definition in PANS − ATM (Doc 4444) FANS 1/A ATN B1 Response Message  Element  Identifier Message Element Intended Use Format for  Message Element Display UM0 UNABLE UM0 UNABLE N RSPU − 1 Indication that the message cannot be complied with. UNABLE UM1 STANDBY UM1 STANDBY N RSPU − 2 Indication that the message will be re- sponded to shortly. STANDBY UM3 ROGER UM3 ROGER N RSPU − 4 Indication that the message is re- ceived. ROGER CPDLC Message Sets Operational Definition in PANS − ATM (Doc 4444) FANS 1/A ATN B1 Response Message  Element  Identifier Message Element Intended Use Format for  Message Element Display DM55 PAN PAN PAN Note −  N response at- tribute N/A Y EMGD − 1 Indication of an ur- gent situation. PAN PAN PAN DM56 MAYDAY MAYDAY MAYDAY Note −  N response at- tribute N/A Y EMGD − 2 Indication of an emergency situa- tion. MAYDAY  MAYDAY DM57 ( remaining fu- el ) OF FUEL RE- MAINING AND  ( remaining souls ) SOULS ON BOARD Note −  N response at- tribute N/A Y EMGD − 3 Report indicating fuel remaining (time) and number of persons on board. (remaining fuel) ENDURANCE AND  (persons on board)  PERSONS ON BOARD DM58 CANCEL EMERGENCY  Note −  N response at- tribute N/A Y EMGD − 4 Indication that the emergency situation is canceled. CANCEL  EMERGENCY 8/15/19 AIM  En Route Procedures 5 − 3 − 8