WINCH_MOTOR_DISABLED
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Applicable alarms (1)
WINCH_MOTOR_DISABLED
Likely outcomes — click to expand
Based on 24,665 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 2,547 ZERP issues filed on these missions)
Top work orders
- EV2: Inspect Aircraft after Droid Left Behind (DLB) · MAINTENANCE_ACTION 627
- Inspect Droid after Droid Left Behind (DLB) · MAINTENANCE_ACTION 429
- EV3: Inspect Aircraft after Droid Left Behind (DLB) · MAINTENANCE_ACTION 337
- Reset Droid after DLB · REPAIR 291
- V4 Zipping Point: Inspect Zipping Point after Droid Left Behind (DLB) - Ranger · MAINTENANCE_ACTION 157
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| ASSY, SPOOL AND LINE, DOCKING FIN, AIRCRAFT, P2 | 48477 | 1,201 |
| WINCH, ASSY, ZIP, P2 | 24078 | 328 |
| DOCKING FIN WINCH ASSY, ZIP, P2 | 24084 | 176 |
| PARALAND ASSY, DROID, P2 | 18427 | 126 |
| LEFT DOOR ASSY, DROID, P2 | 21830 | 105 |
Frequently co-occurring alarms (% of the 24,665 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm occurs during flight or package loading and indicates communication or winch node health issues. The Zip may return to the Dock without delivering or refuse to lower the Droid when docked.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
has-the-droid-been-left-behind-on-this{"<small><b>Step 1</b></small><br/>Question: Has the Droid been left behind on thi..."}
has-the-droid-been-left-behind-2026-15{"<small><b>Step 2</b></small><br/>Question: Has the Droid been left behind on thi..."}
complete-the-following-work-orders["<small><b>Step 3</b></small><br/>Action: Complete the following work orders: -..."]
has-the-droid-been-left-behind-p2topdr{"<small><b>Step 4</b></small><br/>Question: Has the Droid been left behind? How ..."}
has-the-droid-been-left-behind-2026-03{"<small><b>Step 5</b></small><br/>Question: Has the Droid been left behind on thi..."}
perform-the-usual-maintenance-for-a-dro["<small><b>Step 6</b></small><br/>Action: Perform the usual maintenance for a d..."]
wait-for-logs-to-upload["<small><b>Step 7</b></small><br/>Action: Wait for logs to upload."]
was-the-droid-previously-left-behind{"<small><b>Step 8</b></small><br/>Question: Is the line DLB state active, comman..."}
remove-zip-executive-persistent-state["<small><b>Step 9</b></small><br/>Action: SSH into compute A see SSH into Com..."]
verify-zip-executive-persistent-state-removed["<small><b>Step 10</b></small><br/>Action: Run ls /application/state/ and chec..."]
power-cycle-the-zip-and-droid["<small><b>Step 11</b></small><br/>Action: 1. Power cycle the Zip and Droid. 2. ..."]
did-the-wfh-mission-resolve-the-issue{"<small><b>Step 12</b></small><br/>Question: Did the WFH mission resolve the issue?"}
return-the-zip-to-service("<small><b>Step 13</b></small><br/>Reference: Return the Zip to service.")
check-network-switch-metrics-port-winch["<small><b>Step 14</b></small><br/>Telemetry: Review network_switch_metrics_port_w..."]
is-the-connection-bad{"<small><b>Step 15</b></small><br/>Question: Is the connection bad?"}
submit-a-request-for-maintenance-to-per["<small><b>Step 16</b></small><br/>Action: Submit a request for maintenance to p..."]
switch-to-the-winch-motor-disabled-chec["<small><b>Step 17</b></small><br/>Telemetry: Review the startup race condition plo..."]
are-the-following-conditions-being-met{"<small><b>Step 18</b></small><br/>Question: Are the following conditions being me..."}
return-the-aircraft-to-service("<small><b>Step 19</b></small><br/>Reference: Return the aircraft to service.")
switch-to-winch-motor-disabled-check-co["<small><b>Step 20</b></small><br/>Telemetry: Review the compute B-to-A connection ..."]
are-these-conditions-met{"<small><b>Step 21</b></small><br/>Question: Are these conditions met? **NOTE**: T..."}
escalate-to-p2-embedded-platform-on-cal{{"<small><b>Step 22</b></small><br/>Escalation: Escalate to P2 Embedded Platform On C..."}}
escalate-the-ticket-to-p2-droid-control{{"<small><b>Step 23</b></small><br/>Escalation: Escalate the ticket to P2 Droid Contr..."}}
was-the-droid-left-behind-dlb-during-d{"<small><b>Step 24</b></small><br/>Question: Was the Droid left behind DLB durin..."}
was-the-droid-left-behind-dlb-during-p{"<small><b>Step 25</b></small><br/>Question: Was the Droid left behind DLB durin..."}
do-not-place-a-dlb-inspection-on-the-dr["<small><b>Step 26</b></small><br/>Action: Do not place a DLB inspection on the ..."]
raise-a-discrepancy-against-the-droid-t["<small><b>Step 27</b></small><br/>Action: Raise a discrepancy against the Droid..."]
inspect-the-droid-droid-cmm-droid-left["<small><b>Step 28</b></small><br/>Action: Inspect the Droid Droid CMM: Droid ..."]
did-the-inspection-pass{"<small><b>Step 29</b></small><br/>Question: Did the inspection pass?"}
if-there-is-a-clear-root-cause-perform{{"<small><b>Step 30</b></small><br/>Escalation: If there is a clear root cause, perfo..."}}
reset-the-aircraft-umm["<small><b>Step 31</b></small><br/>Action: Reset the Aircraft UMM 5.5.1.e Rese..."]
inspect-the-flex-harness-standoffs-on-t{"<small><b>Step 32</b></small><br/>Question: Inspect the flex harness standoffs on..."}
replace-the-docking-fin-winch-assembly["<small><b>Step 33</b></small><br/>Action: Replace the Docking Fin Winch Assembl..."]
replace-the-docking-fin-to-tail-node-fl["<small><b>Step 34</b></small><br/>Action: Replace the Docking fin to tail node ..."]
after-maintenance-is-complete-perform-a["<small><b>Step 35</b></small><br/>Action: After maintenance is complete, perfor..."]
is-the-issue-resolved-winch{"<small><b>Step 36</b></small><br/>Question: Is the issue resolved?"}
the-aircraft-may-return-to-service("<small><b>Step 37</b></small><br/>Reference: The Aircraft may return to service.")
escalate-to-the-owner-of-the-swapped-hw{{"<small><b>Step 38</b></small><br/>Escalation: Escalate to the owner of the swapped ..."}}
has-the-droid-been-left-behind-on-this -->|Yes| was-the-droid-left-behind-dlb-during-d
has-the-droid-been-left-behind-on-this -->|No| wait-for-logs-to-upload
has-the-droid-been-left-behind-2026-15 -->|Yes| complete-the-following-work-orders
has-the-droid-been-left-behind-2026-15 -->|No| wait-for-logs-to-upload
has-the-droid-been-left-behind-p2topdr -->|Yes| was-the-droid-left-behind-dlb-during-d
has-the-droid-been-left-behind-p2topdr -->|No| wait-for-logs-to-upload
has-the-droid-been-left-behind-2026-03 -->|Yes| perform-the-usual-maintenance-for-a-dro
has-the-droid-been-left-behind-2026-03 -->|No| wait-for-logs-to-upload
wait-for-logs-to-upload --> was-the-droid-previously-left-behind
was-the-droid-previously-left-behind -->|Yes, the line is present| remove-zip-executive-persistent-state
was-the-droid-previously-left-behind -->|No, the line is not present| check-network-switch-metrics-port-winch
remove-zip-executive-persistent-state --> verify-zip-executive-persistent-state-removed
verify-zip-executive-persistent-state-removed --> power-cycle-the-zip-and-droid
power-cycle-the-zip-and-droid --> did-the-wfh-mission-resolve-the-issue
did-the-wfh-mission-resolve-the-issue -->|Yes| return-the-zip-to-service
did-the-wfh-mission-resolve-the-issue -->|No| check-network-switch-metrics-port-winch
check-network-switch-metrics-port-winch --> is-the-connection-bad
is-the-connection-bad -->|Yes| submit-a-request-for-maintenance-to-per
is-the-connection-bad -->|No| switch-to-the-winch-motor-disabled-chec
switch-to-the-winch-motor-disabled-chec --> are-the-following-conditions-being-met
are-the-following-conditions-being-met -->|Yes| return-the-aircraft-to-service
are-the-following-conditions-being-met -->|No| switch-to-winch-motor-disabled-check-co
switch-to-winch-motor-disabled-check-co --> are-these-conditions-met
are-these-conditions-met -->|Yes| escalate-to-p2-embedded-platform-on-cal
are-these-conditions-met -->|No| escalate-the-ticket-to-p2-droid-control
was-the-droid-left-behind-dlb-during-d -->|Yes| do-not-place-a-dlb-inspection-on-the-dr
was-the-droid-left-behind-dlb-during-d -->|No| raise-a-discrepancy-against-the-droid-t
was-the-droid-left-behind-dlb-during-p -->|Yes| do-not-place-a-dlb-inspection-on-the-dr
was-the-droid-left-behind-dlb-during-p -->|No| raise-a-discrepancy-against-the-droid-t
raise-a-discrepancy-against-the-droid-t --> inspect-the-droid-droid-cmm-droid-left
inspect-the-droid-droid-cmm-droid-left --> did-the-inspection-pass
did-the-inspection-pass -->|Yes| reset-the-aircraft-umm
did-the-inspection-pass -->|No| if-there-is-a-clear-root-cause-perform
inspect-the-flex-harness-standoffs-on-t -->|Yes| replace-the-docking-fin-winch-assembly
inspect-the-flex-harness-standoffs-on-t -->|No| replace-the-docking-fin-to-tail-node-fl
replace-the-docking-fin-winch-assembly --> after-maintenance-is-complete-perform-a
replace-the-docking-fin-to-tail-node-fl --> after-maintenance-is-complete-perform-a
after-maintenance-is-complete-perform-a --> is-the-issue-resolved-winch
is-the-issue-resolved-winch -->|Yes| the-aircraft-may-return-to-service
is-the-issue-resolved-winch -->|No| escalate-to-the-owner-of-the-swapped-hw
style has-the-droid-been-left-behind-on-this fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style has-the-droid-been-left-behind-2026-15 fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style complete-the-following-work-orders fill:#dcfce7,stroke:#22c55e,color:#14532d
style has-the-droid-been-left-behind-p2topdr fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style has-the-droid-been-left-behind-2026-03 fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style perform-the-usual-maintenance-for-a-dro fill:#dcfce7,stroke:#22c55e,color:#14532d
style wait-for-logs-to-upload fill:#dcfce7,stroke:#22c55e,color:#14532d
style was-the-droid-previously-left-behind fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style remove-zip-executive-persistent-state fill:#dcfce7,stroke:#22c55e,color:#14532d
style verify-zip-executive-persistent-state-removed fill:#dcfce7,stroke:#22c55e,color:#14532d
style power-cycle-the-zip-and-droid fill:#dcfce7,stroke:#22c55e,color:#14532d
style did-the-wfh-mission-resolve-the-issue fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-the-zip-to-service fill:#f3e8ff,stroke:#a855f7,color:#581c87
style is-the-connection-bad fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style submit-a-request-for-maintenance-to-per fill:#dcfce7,stroke:#22c55e,color:#14532d
style are-the-following-conditions-being-met fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-the-aircraft-to-service fill:#f3e8ff,stroke:#a855f7,color:#581c87
style are-these-conditions-met fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style escalate-to-p2-embedded-platform-on-cal fill:#fef3c7,stroke:#f59e0b,color:#78350f
style escalate-the-ticket-to-p2-droid-control fill:#fef3c7,stroke:#f59e0b,color:#78350f
style was-the-droid-left-behind-dlb-during-d fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style was-the-droid-left-behind-dlb-during-p fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style do-not-place-a-dlb-inspection-on-the-dr fill:#dcfce7,stroke:#22c55e,color:#14532d
style raise-a-discrepancy-against-the-droid-t fill:#dcfce7,stroke:#22c55e,color:#14532d
style inspect-the-droid-droid-cmm-droid-left fill:#dcfce7,stroke:#22c55e,color:#14532d
style did-the-inspection-pass fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style if-there-is-a-clear-root-cause-perform fill:#fef3c7,stroke:#f59e0b,color:#78350f
style reset-the-aircraft-umm fill:#dcfce7,stroke:#22c55e,color:#14532d
style inspect-the-flex-harness-standoffs-on-t fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style replace-the-docking-fin-winch-assembly fill:#dcfce7,stroke:#22c55e,color:#14532d
style replace-the-docking-fin-to-tail-node-fl fill:#dcfce7,stroke:#22c55e,color:#14532d
style after-maintenance-is-complete-perform-a fill:#dcfce7,stroke:#22c55e,color:#14532d
style is-the-issue-resolved-winch fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style the-aircraft-may-return-to-service fill:#f3e8ff,stroke:#a855f7,color:#581c87
style escalate-to-the-owner-of-the-swapped-hw fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question 2026.09
Has the Droid been left behind on this flight? Follow this guide: How to Check if Droid is Left Behind.
2 question >=2026.15
Has the Droid been left behind on this flight? Follow this guide: How to Check if Droid is Left Behind.
3 action >=2026.15
Complete the following work orders:
- Aircraft: Complete the work order for the relevant aircraft version:
- EV2: #195: Inspect Aircraft after Droid Left Behind (DLB)
- EV3: #662: Inspect Aircraft after Droid Left Behind (DLB)
- Droid: #1169: Reset Droid after DLB.
- Aircraft: Complete the work order for the relevant aircraft version:
- EV2: #195: Inspect Aircraft after Droid Left Behind (DLB)
- EV3: #662: Inspect Aircraft after Droid Left Behind (DLB)
- Droid: #1169: Reset Droid after DLB.
4 question
Has the Droid been left behind? How to Check if Droid is Left Behind.
5 question 2026.03
Has the Droid been left behind on this flight? Follow this guide: How to Check if Droid is Left Behind.
6 action 2026.03
Perform the usual maintenance for a droid left behind. This alarm can be safely ignored - it is expected in this case.
7 action
Wait for logs to upload.
8 question
Is the line
If this line is present, it indicates that the Zip recently had a DLB and the Droid has since been re-installed.
DLB state active, commanding winch FREEWHEEL present in the executive.service journal logs in Baraza?If this line is present, it indicates that the Zip recently had a DLB and the Droid has since been re-installed.
9 action
SSH into compute A (see SSH into Compute A/B). Remove the persistent state files by running:
You may need to press
rm /application/state/zip_executive_persistent_state.a /application/state/zip_executive_persistent_state.bYou may need to press
y to confirm that you want to delete the files. 10 action
Run
ls /application/state/ and check that zip_executive_persistent_state.a and zip_executive_persistent_state.b are gone. If either file is still present, re-attempt the file removal. 11 action
1. Power cycle the Zip and Droid.
2. Wait ~5 minutes to ensure the Zip is in Sleep.
3. Send a WFH mission.
2. Wait ~5 minutes to ensure the Zip is in Sleep.
3. Send a WFH mission.
12 question
Did the WFH mission resolve the issue?
13 reference
Return the Zip to service.
14 telemetry
Review
NOTE: The plot below is an example of a bad connection.
network_switch_metrics_port_winch.link_status to determine whether the winch ethernet is properly connected. Add 30s of padding if the plot appears blank; some missions fail so quickly that no messages were sent while the mission was active. A healthy connection will always show a value of LINK_UP. If the link status is LINK_DOWN some or all of the time, it is a bad connection.NOTE: The plot below is an example of a bad connection.
Enter the mission identifier above to load the plot.
15 question
Is the connection bad?
16 action
Submit a request for maintenance to perform a winch inspection. See Winch Inspection Procedure below.
17 telemetry
Review the startup race condition plot with 5s of padding.
Enter the mission identifier above to load the plot.
18 question
Are the following conditions being met?
- The winch gnc sequence number resets to zero while the task_name is LowerDroid
- The duration of StartUp is < 1s
- The duration of Sleep is < 4s
NOTE: The plot below is an example of the conditions being met.
- The winch gnc sequence number resets to zero while the task_name is LowerDroid
- The duration of StartUp is < 1s
- The duration of Sleep is < 4s
NOTE: The plot below is an example of the conditions being met.
19 reference
Return the aircraft to service.
20 telemetry
Review the compute B-to-A connection plot with 30s of padding. Check for a gap on the top plot but not the middle plot that's lined up with the WINCH_MOTOR_DISABLED signal on the bottom plot being true.
Enter the mission identifier above to load the plot.
21 question
Are these conditions met?
NOTE: The plot below is an example of the conditions being met.
NOTE: The plot below is an example of the conditions being met.
22 escalation
Escalate to P2 Embedded Platform On Call.
23 escalation
Escalate the ticket to P2 Droid Controls & Dynamics On Call.
24 question >=2026.09
Was the Droid left behind (DLB) during Drone Loading (formally known as Ground Loading)?
25 question
Was the Droid left behind (DLB) during Drone Loading (formally known as Ground Loading)?
26 action
Do not place a DLB inspection on the Droid.
Reset the Aircraft (UMM 5.5.1.e Reset Zip After Droid Left Behind).
Reset the Aircraft (UMM 5.5.1.e Reset Zip After Droid Left Behind).
27 action
Raise a discrepancy against the Droid that was left behind.
28 action
Inspect the Droid (Droid CMM: Droid Left Behind Inspection).
29 question
Did the inspection pass?
30 escalation
If there is a clear root cause, perform applicable maintenance if required. Otherwise, escalate to P2 Droid Autonomy On Call.
31 action
Reset the Aircraft (UMM 5.5.1.e Reset Zip After Droid Left Behind).
32 question
Inspect the flex harness standoffs on the winch PCBA. Looks for signs of the standoff being pulled out of the board: cracked solder or a very obvious tear out. Is damage present?
33 action
Replace the Docking Fin Winch Assembly.
1. Link the issue as "Caused by" PT-6176 and assign to Johnny Sun
2. Swap the winch motor.
- UMM 32.3.1.b: Remove Winch Assembly
- UMM 32.3.1.c: Install Winch Assembly
3. Send the damaged motor to the Aviary addressed to Johnny Sun
1. Link the issue as "Caused by" PT-6176 and assign to Johnny Sun
2. Swap the winch motor.
- UMM 32.3.1.b: Remove Winch Assembly
- UMM 32.3.1.c: Install Winch Assembly
3. Send the damaged motor to the Aviary addressed to Johnny Sun
34 action
Replace the Docking fin to tail node flex harness.
1. Link the issue as "Caused by" AVI-2195 and assign to Kunal Verma
2. Swap the flex.
- UMM 20.2.3.d: Remove and Install PCB Harness
- UMM 20.5: Electrical Standard Practices
3. Send the damaged flex to the Aviary addressed to Kunal Verma
1. Link the issue as "Caused by" AVI-2195 and assign to Kunal Verma
2. Swap the flex.
- UMM 20.2.3.d: Remove and Install PCB Harness
- UMM 20.5: Electrical Standard Practices
3. Send the damaged flex to the Aviary addressed to Kunal Verma
35 action
After maintenance is complete, perform a Droid raise and lower test up to three (3) times.
36 question
Is the issue resolved?
37 reference
The Aircraft may return to service.
38 escalation
Escalate to the owner of the swapped hardware:
- Winch: Powertrain On Call P2 Firmware Motors On Call
- Winch flex: Avionics P2 Avionics Hardware On Call
- Winch: Powertrain On Call P2 Firmware Motors On Call
- Winch flex: Avionics P2 Avionics Hardware On Call
Resolution note
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Winch Inspection Procedure
Section titled “Winch Inspection Procedure”There are 2 physical root causes of a physical comms issue on the winch: The standoffs on the winch PCBA can get damaged and tear out OR the flex harness going to the winch is damaged. Follow the steps below to determine which one is damaged.
WORK ORDER TEMPLATE: Use Work Order Template #503: Winch Inspection.
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