PROXIMITY_ALERT
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Applicable alarms (1)
PROXIMITY_ALERT
Likely outcomes — click to expand
Based on 277 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 174 ZERP issues filed on these missions)
Top work orders
- Perform Post-Paraland Inspection on Aircraft · MAINTENANCE_ACTION 29
- Perform Post-Paraland Inspection on Droid · ADMINISTRATIVE 23
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| BATTERY ASSY, ZIP, P2 | 27158 | 248 |
| PRE-PREG TAIL ASSY STBD(RH), DEPOP, ZIP, P2 | 21840 | 80 |
| TAIL PORT DEPOP, ZIP, P2 | 31280 | 76 |
| CCW HOVER PROPELLER BLADE, ZIP, P2 | 29857 | 55 |
| T800 CW HOVER PROPELLER, ZIP, P2 | 31101 | 50 |
Frequently co-occurring alarms (% of the 277 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm occurs when the Terrain Proximity Check concludes that the Zip is violating map clearance requirements, for example, distance to terrain and/or keep-out zones.
If this alarms occurs in preflight, it usually indicates a high degree of navigation error which would prevent the Zip from taking off.
If the alarm occurs during flight, it is expected to trigger a paraland. The root cause of the loss of sufficient clearance should be investigated. It may be due to error in navigation, motion planning, or GNC.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
does-the-alarm-cause-preflight-failure-or-flight-failure-paraland{"<small><b>Step 1</b></small><br/>Question: Does the alarm cause preflight failur..."}
does-the-operations-mode-show-autonomyd{"<small><b>Step 2</b></small><br/>Question: Does the operations mode show Autono..."}
restart-zip-exec["<small><b>Step 3</b></small><br/>Action: Restart Zip Executive/procedures/r..."]
wait-until-the-aircraft-is-in-operation["<small><b>Step 4</b></small><br/>Action: Wait until the Aircraft is in Operati..."]
if-the-proximity-alarm-is-still-set-esc{"<small><b>Step 5</b></small><br/>Question: Is the PROXIMITY_ALARM still set?"}
escalate-to-p2-nav-on-call{{"<small><b>Step 6</b></small><br/>Escalation: Escalate to P2 Nav On Call."}}
the-aircraft-may-return-to-service["<small><b>Step 7</b></small><br/>Action: The Aircraft may return to service."]
retry-the-mission["<small><b>Step 8</b></small><br/>Action: Retry the mission."]
if-the-proximity-alarm-is-still-set-es2{{"<small><b>Step 9</b></small><br/>Escalation: If the PROXIMITY_ALARM is still set, ..."}}
conduct-incident-response-and-escalate{{"<small><b>Step 10</b></small><br/>Escalation: Conduct incident response and escalat..."}}
does-the-alarm-cause-preflight-failure-or-flight-failure-paraland -->|Alarm causes preflight failure| does-the-operations-mode-show-autonomyd
does-the-alarm-cause-preflight-failure-or-flight-failure-paraland -->|Alarm causes flight failure...| conduct-incident-response-and-escalate
does-the-operations-mode-show-autonomyd -->|Yes| restart-zip-exec
does-the-operations-mode-show-autonomyd -->|No| retry-the-mission
restart-zip-exec --> wait-until-the-aircraft-is-in-operation
wait-until-the-aircraft-is-in-operation --> if-the-proximity-alarm-is-still-set-esc
if-the-proximity-alarm-is-still-set-esc -->|Yes| escalate-to-p2-nav-on-call
if-the-proximity-alarm-is-still-set-esc -->|No| the-aircraft-may-return-to-service
retry-the-mission --> if-the-proximity-alarm-is-still-set-es2
style does-the-alarm-cause-preflight-failure-or-flight-failure-paraland fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style does-the-operations-mode-show-autonomyd fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style restart-zip-exec fill:#dcfce7,stroke:#22c55e,color:#14532d
style wait-until-the-aircraft-is-in-operation fill:#dcfce7,stroke:#22c55e,color:#14532d
style if-the-proximity-alarm-is-still-set-esc fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style escalate-to-p2-nav-on-call fill:#fef3c7,stroke:#f59e0b,color:#78350f
style the-aircraft-may-return-to-service fill:#dcfce7,stroke:#22c55e,color:#14532d
style retry-the-mission fill:#dcfce7,stroke:#22c55e,color:#14532d
style if-the-proximity-alarm-is-still-set-es2 fill:#fef3c7,stroke:#f59e0b,color:#78350f
style conduct-incident-response-and-escalate fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Does the alarm cause preflight failure or flight failure/paraland?
2 question
Does the operations mode show
AutonomyDeactivatedUntilReset: 3 action
4 action
Wait until the Aircraft is in Operations mode: Standard.
5 question
Is the PROXIMITY_ALARM still set?
7 action
The Aircraft may return to service.
8 action
Retry the mission.
9 escalation
If the PROXIMITY_ALARM is still set, escalate to P2 Nav On Call.
10 escalation
Conduct incident response and escalate to P2 Zip Autonomy On Call.
Resolution note
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Example ZipMissionLog
Section titled “Example ZipMissionLog”Example ZipMissionLog for a failure due to PROXIMITY_ALERT. The error report can be found in the failure_summaries field.
The error report is caused by an alarm. There is no alarm report, so no alarm report appears in the error report.
{ "status": "ZIP_MISSION_STATUS_ENDED_IN_FAILURE", "asset_id": "p2-zip-371", "dock_ids": [ "p2-dock-84" ], "droid_id": "p2-droid-499", "timestamp": "2025-05-07T19:41:43.781Z", "flight_ids": [ "P2F_65AB1116D7C1594C" ], "mission_id": "P2M_65AB11142DC00000", "ibit_status": [], "capabilities": { "can_dock": "CAPABILITY_STATUS_DISABLED", "can_avoid": "CAPABILITY_STATUS_UNSPECIFIED", "can_hover": "CAPABILITY_STATUS_AVAILABLE", "can_cruise": "CAPABILITY_STATUS_AVAILABLE", "can_launch": "CAPABILITY_STATUS_FAILED", "can_deliver": "CAPABILITY_STATUS_DISABLED", "can_transit": "CAPABILITY_STATUS_AVAILABLE", "has_package": "CAPABILITY_STATUS_DISABLED", "can_failover": "CAPABILITY_STATUS_UNSPECIFIED", "can_paraland": "CAPABILITY_STATUS_DISABLED", "is_on_ground": "CAPABILITY_STATUS_DISABLED", "are_motors_off": "CAPABILITY_STATUS_AVAILABLE", "can_deconflict": "CAPABILITY_STATUS_UNSPECIFIED", "can_spin_motors": "CAPABILITY_STATUS_DISABLED", "is_droid_stowed": "CAPABILITY_STATUS_DISABLED", "can_perform_ibit": "CAPABILITY_STATUS_AVAILABLE", "can_control_droid": "CAPABILITY_STATUS_AVAILABLE", "can_control_winch": "CAPABILITY_STATUS_UNSPECIFIED", "is_droid_lid_open": "CAPABILITY_STATUS_DISABLED", "is_compute_healthy": "CAPABILITY_STATUS_UNSPECIFIED", "is_crossfire_alive": "CAPABILITY_STATUS_DISABLED", "is_droid_in_portal": "CAPABILITY_STATUS_AVAILABLE", "can_gnc_spin_motors": "CAPABILITY_STATUS_DISABLED", "is_in_dock_corridor": "CAPABILITY_STATUS_DISABLED", "is_retained_on_dock": "CAPABILITY_STATUS_AVAILABLE", "has_passed_all_ibits": "CAPABILITY_STATUS_DISABLED", "is_retracted_on_dock": "CAPABILITY_STATUS_AVAILABLE", "is_transit_completed": "CAPABILITY_STATUS_DISABLED", "can_transit_nominally": "CAPABILITY_STATUS_UNSPECIFIED", "is_cut_line_completed": "CAPABILITY_STATUS_UNSPECIFIED", "is_delivery_completed": "CAPABILITY_STATUS_DISABLED", "is_take_off_completed": "CAPABILITY_STATUS_DISABLED", "can_transit_with_droid": "CAPABILITY_STATUS_UNSPECIFIED", "is_call_home_completed": "CAPABILITY_STATUS_UNSPECIFIED", "can_reach_mission_goals": "CAPABILITY_STATUS_AVAILABLE", "is_dock_motion_completed": "CAPABILITY_STATUS_DISABLED", "is_lower_droid_completed": "CAPABILITY_STATUS_DISABLED", "is_raise_droid_completed": "CAPABILITY_STATUS_DISABLED", "can_droid_lower_to_portal": "CAPABILITY_STATUS_DISABLED", "are_diagnostic_ibits_reset": "CAPABILITY_STATUS_DISABLED", "can_droid_raise_from_portal": "CAPABILITY_STATUS_AVAILABLE", "can_receive_delivery_mission": "CAPABILITY_STATUS_AVAILABLE", "has_received_pending_mission": "CAPABILITY_STATUS_DISABLED", "is_take_off_time_window_open": "CAPABILITY_STATUS_AVAILABLE", "can_droid_execute_motion_cmds": "CAPABILITY_STATUS_UNSPECIFIED", "has_received_delivery_mission": "CAPABILITY_STATUS_DISABLED", "is_crossfire_disarm_requested": "CAPABILITY_STATUS_DISABLED", "is_diagnostic_abort_requested": "CAPABILITY_STATUS_DISABLED", "is_performing_partial_takeoff": "CAPABILITY_STATUS_DISABLED", "are_diagnostic_ibits_completed": "CAPABILITY_STATUS_DISABLED", "can_receive_reposition_mission": "CAPABILITY_STATUS_AVAILABLE", "is_software_download_completed": "CAPABILITY_STATUS_DISABLED", "has_received_reposition_mission": "CAPABILITY_STATUS_DISABLED", "is_crossfire_gnc_mode_requested": "CAPABILITY_STATUS_DISABLED", "is_crossfire_paraland_requested": "CAPABILITY_STATUS_DISABLED", "is_delivery_hydration_completed": "CAPABILITY_STATUS_DISABLED", "can_communicate_with_remote_pilot": "CAPABILITY_STATUS_AVAILABLE", "is_winch_emergency_hold_completed": "CAPABILITY_STATUS_UNSPECIFIED", "is_emergency_lower_droid_completed": "CAPABILITY_STATUS_UNSPECIFIED" }, "failure_summaries": [ "gps_timestamp": 1746042167544960000, "error_report": { "primary_unique_error_id": "ERR_123456", "errors": { "ERR_123456": { "code": 0x00010005, "message": "CanLaunch failed", "gps_timestamp": 173651165380000000, "unix_timestamp": 1024658498.45, "unique_id": "ERR_5123541254", "related_alarm_summaries": [{ "relation_type": RelationType::CAUSED_BY, "alarm": { "alarm_id": 17, "identifier": "/compute_a.zip_onboard_map_service.terrain_proximity_check_result", "name": "PROXIMITY_ALERT", "alarm_namespace": "alarms", } }] } } }, "executive_task": "RunPreliminaryChecks", "flight_id": "P2F_65AB1116D7C1594C", "droid_status": { "lid_open": false, "behaviors": [], "motion_state": "", "battery_status": { "pack_current": 1.2839198, "pack_voltage": 19.84253, "state_of_charge": 0.7585616, "unsafe_to_charge": false, "unsafe_to_deploy": false, "unsafe_to_operate": false, "ms_since_relaxation": "182098", "requires_maintenance": false }, "capability_map": {}, "droid_asset_id": "p2-droid-499", "is_finger_safe": false, "current_executive_id": { "step_id": "1", "task_id": "8", "mission_id": "P2M_1AA5EDA994800000", "sequence_id": "15475" }, "safety_system_status": "DROID_SAFETY_SYSTEM_STATUS_NOT_READY", "current_command_status": "DROID_COMMAND_STATUS_COMPLETED", "current_command_string": "Portal (\"LOWER_TO_PORTAL\")", "message_injection_state": { "metadata": "", "is_running": false, "config_path": "" }, "droid_parachute_deploy_reason": "DROID_PARACHUTE_DEPLOY_UNSPECIFIED" }, "flight_status": "FLIGHT_STATUS_FAILED", "winch_cutter_state": "WINCH_CUTTER_STATE_UNARMED", "active_alarms": [ { "identifier": "/tail_bridge.comm_status", "alarm_summaries": [ { "name": "RS485_SERVO_TAIL_STBD_FWD_SIGNAL_QUALITY_OFF_NOMINAL", "alarm_id": 0, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "off_nominals" }, { "name": "RS485_SERVO_TAIL_PORT_FWD_SIGNAL_QUALITY_OFF_NOMINAL", "alarm_id": 1, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "off_nominals" }, { "name": "RS485_SERVO_ROLL_SIGNAL_QUALITY_OFF_NOMINAL", "alarm_id": 2, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "off_nominals" }, { "name": "RS485_SERVO_TILT_SIGNAL_QUALITY_OFF_NOMINAL", "alarm_id": 3, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "off_nominals" }, { "name": "RS485_SERVO_TAIL_STBD_FWD_LINK_FAULT", "alarm_id": 0, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" }, { "name": "RS485_SERVO_TAIL_PORT_FWD_LINK_FAULT", "alarm_id": 1, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" }, { "name": "RS485_SERVO_ROLL_LINK_FAULT", "alarm_id": 2, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" }, { "name": "RS485_SERVO_TILT_LINK_FAULT", "alarm_id": 3, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" } ] }, { "identifier": "zip_executive.executive_status", "alarm_summaries": [ { "name": "ZIP_MOTOR_CONTROL_UNINITIALIZED", "alarm_id": 18, "severity": "ALARM_WARNING", "report_id": "", "visibility": "MAINTENANCE", "alarm_namespace": "alarms" } ] }, { "identifier": "mic_array_summary", "alarm_summaries": [ { "name": "ACOUSTIC_PROBES_DEGRADED", "alarm_id": 0, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" } ] }, { "identifier": "service_health_monitor.health", "alarm_summaries": [ { "name": "SERVICE_RESTARTED", "alarm_id": 0, "severity": "ALARM_INFO", "report_id": "p2-zip-371-service_health_monitor.alarm_report-1746646143.29986-0", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" }, { "name": "SERVICE_NOT_ACTIVE", "alarm_id": 1, "severity": "ALARM_INFO", "report_id": "p2-zip-371-service_health_monitor.alarm_report-1746643615.5932901-1", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" } ] } ], "occupied_bay_ids": [ "bay_8550db1c-76d5-46b4-bea8-47fec5924a0b" ], "proto_build_info": { "winch": { "app": { "git_sha": "d9d5887fdf9c6947aa861274e3421b349976915e", "has_uncommitted_changes": true }, "boot": { "git_sha": "bbb73bacd0e169086df33ac252b119556d265b8e", "has_uncommitted_changes": false } }, "distro_a": { "app": { "git_sha": "d9d5887fdf9c6947aa861274e3421b349976915e", "has_uncommitted_changes": true }, "boot": { "git_sha": "bbb73bacd0e169086df33ac252b119556d265b8e", "has_uncommitted_changes": false } }, "distro_b": { "app": { "git_sha": "d9d5887fdf9c6947aa861274e3421b349976915e", "has_uncommitted_changes": true }, "boot": { "git_sha": "bbb73bacd0e169086df33ac252b119556d265b8e", "has_uncommitted_changes": false } }, "zip_linux_sha": "3e736e17027ed2bd2917470568247e3f2a0aae7e", "flight_systems_sha": "d9d5887fdf9c6947aa861274e3421b349976915e", "compute_b_zip_linux_sha": "3e736e17027ed2bd2917470568247e3f2a0aae7e", "compute_b_flight_systems_sha": "d9d5887fdf9c6947aa861274e3421b349976915e" }, "software_config_status": { "config_state": "CONFIG_STATE_UNSPECIFIED", "release_name": "fsw-2025.15.rc15", "configuration_id": "46d69824-fd0d-4d49-8364-f43133e66776" }, "message_injection_state": { "is_running": false }, "parachute_deploy_reason": "PARACHUTE_DEPLOY_UNSPECIFIED", "winch_cutter_deploy_reason": "WINCH_CUT_UNSPECIFIED", "droid_parachute_deploy_reason": "DROID_PARACHUTE_DEPLOY_UNSPECIFIED", "mission_status_unix_timestamps": { "ZIP_MISSION_STATUS_FAILED": 1746646903.53002, "ZIP_MISSION_STATUS_ACCEPTED": 1746646883.17058, "ZIP_MISSION_STATUS_ENDED_IN_FAILURE": 1746646903.53017 }}Did this guide help you get unblocked?
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