DROID_TO_WINCH_STALE
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Applicable alarms (1)
DROID_TO_WINCH_STALE
Likely outcomes — click to expand
Based on 277,221 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 2,032 ZERP issues filed on these missions)
Top work orders
- EV2: Inspect Aircraft after Droid Left Behind (DLB) · MAINTENANCE_ACTION 333
- EV2/EV3 Perform Preflight Without Motors · INSPECTION 315
- Inspect Droid after Droid Left Behind (DLB) · MAINTENANCE_ACTION 229
- Perform a Droid Health Check on Droid · INSPECTION 78
- V4 Zipping Point: Inspect Zipping Point after Droid Left Behind (DLB) - Ranger · MAINTENANCE_ACTION 75
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| SERVO, ASSY, UNIVERSAL, P2 | 20398 | 809 |
| CCW HOVER MOTOR ASSY, ZIP, P2 | 19607 | 710 |
| WING PORT, ZIP, P2 | 24762 | 498 |
| WING STBD, ZIP, P2 | 25266 | 498 |
| CW HOVER MOTOR ASSY, ZIP, P2 | 33333 | 380 |
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm occurs when the winch gnc process is not receiving messages from the droid. This can indicate that vertical comms is off or errored. It can also indicate time sync issues that cause messages to be rejected.
If we are not in ExecutiveTask LowerDroid, RaiseDroid, or Delivery, this alarm is expected to be on and will not cause a failure.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
did-the-alarm-occur-during-a-dlb{"<small><b>Step 1</b></small><br/>Question: Did the alarm occur during a Droid Le..."}
complete-the-dlb-work-orders["<small><b>Step 2</b></small><br/>Action: Complete the work orders listed below..."]
check-the-droid-to-winch-stale-alarm-re{"<small><b>Step 3</b></small><br/>Question: Check the DROID_TO_WINCH_STALE alarm ..."}
follow-steps-in-clock-error-is-high["<small><b>Step 4</b></small><br/>Action: Follow steps in CLOCK_ERROR_IS_HIGH..."]
send-the-aircraft-on-another-mission["<small><b>Step 5</b></small><br/>Action: Send the Aircraft on another mission."]
is-the-issue-resolved{"<small><b>Step 6</b></small><br/>Question: Is the issue resolved?"}
return-the-aircraft-to-service("<small><b>Step 7</b></small><br/>Reference: Return the Aircraft to service.")
escalate-to-embedded-linux-on-call{{"<small><b>Step 8</b></small><br/>Escalation: Escalate to P2 Embedded Linux On Call."}}
power-cycle-the-aircraft-and-droid-for["<small><b>Step 9</b></small><br/>Action: Power cycle the Aircraft and Droid. F..."]
send-the-aircraft-on-another-mission-2["<small><b>Step 10</b></small><br/>Action: Send the Aircraft on another mission."]
is-the-issue-resolved-2{"<small><b>Step 11</b></small><br/>Question: Is the issue resolved?"}
the-aircraft-can-return-to-service["<small><b>Step 12</b></small><br/>Action: The Aircraft can return to service."]
escalate-to-embedded-linux-on-call-2{{"<small><b>Step 13</b></small><br/>Escalation: Escalate to P2 Embedded Linux On Call."}}
did-the-alarm-occur-during-a-dlb -->|Yes| complete-the-dlb-work-orders
did-the-alarm-occur-during-a-dlb -->|No| check-the-droid-to-winch-stale-alarm-re
check-the-droid-to-winch-stale-alarm-re -->|Yes| follow-steps-in-clock-error-is-high
check-the-droid-to-winch-stale-alarm-re -->|No| power-cycle-the-aircraft-and-droid-for
follow-steps-in-clock-error-is-high --> send-the-aircraft-on-another-mission
send-the-aircraft-on-another-mission --> is-the-issue-resolved
is-the-issue-resolved -->|Yes| return-the-aircraft-to-service
is-the-issue-resolved -->|No| escalate-to-embedded-linux-on-call
power-cycle-the-aircraft-and-droid-for --> send-the-aircraft-on-another-mission-2
send-the-aircraft-on-another-mission-2 --> is-the-issue-resolved-2
is-the-issue-resolved-2 -->|Yes| the-aircraft-can-return-to-service
is-the-issue-resolved-2 -->|No| escalate-to-embedded-linux-on-call-2
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style complete-the-dlb-work-orders fill:#dcfce7,stroke:#22c55e,color:#14532d
style check-the-droid-to-winch-stale-alarm-re fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style follow-steps-in-clock-error-is-high fill:#dcfce7,stroke:#22c55e,color:#14532d
style send-the-aircraft-on-another-mission fill:#dcfce7,stroke:#22c55e,color:#14532d
style is-the-issue-resolved fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-the-aircraft-to-service fill:#f3e8ff,stroke:#a855f7,color:#581c87
style escalate-to-embedded-linux-on-call fill:#fef3c7,stroke:#f59e0b,color:#78350f
style power-cycle-the-aircraft-and-droid-for fill:#dcfce7,stroke:#22c55e,color:#14532d
style send-the-aircraft-on-another-mission-2 fill:#dcfce7,stroke:#22c55e,color:#14532d
style is-the-issue-resolved-2 fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style the-aircraft-can-return-to-service fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-to-embedded-linux-on-call-2 fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Did the alarm occur during a Droid Left Behind (DLB) event?
2 action
Complete the work orders listed below:
• 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: Complete the following work orders in order:
1. #1169: Reset Droid after DLB
2. #1196: Offload Droid Logs after DLB
3. #1305: Perform Droid WiFi Test 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: Complete the following work orders in order:
1. #1169: Reset Droid after DLB
2. #1196: Offload Droid Logs after DLB
3. #1305: Perform Droid WiFi Test after DLB
3 question
Check the DROID_TO_WINCH_STALE alarm report (Aircraft/Droid Alarm Report). Is the rejected_message_count greater than zero?
4 action
Follow steps in CLOCK_ERROR_IS_HIGH.
5 action
Send the Aircraft on another mission.
6 question
Is the issue resolved?
7 reference
Return the Aircraft to service.
8 escalation
Escalate to P2 Embedded Linux On Call.
9 action
Power cycle the Aircraft and Droid. For steps, see Power Cycle Aircraft, Power Cycle Droid.
10 action
Send the Aircraft on another mission.
11 question
Is the issue resolved?
12 action
The Aircraft can return to service.
13 escalation
Escalate to P2 Embedded Linux On Call.
Resolution note
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