UNEXPECTED_DROID_UNCONSTRAINED
Applicable alarms (1)
Likely outcomes — click to expand
Based on 44 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 59 ZERP issues filed on these missions)
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| PARALAND ASSY, DROID, P2 | 18427 | 28 |
| ASSY, SPOOL AND LINE, DOCKING FIN, AIRCRAFT, P2 | 48477 | 28 |
| WINCH, ASSY, ZIP, P2 | 24078 | 16 |
| BATTERY ASSY, ZIP, P2 | 27158 | 12 |
| BRAIN, LRU, DROID, P2 | 31920 | 10 |
Frequently co-occurring alarms (% of the 44 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 Zip Exec detects that the Droid has become unconstrained (not contained within the Aircraft) at an unexpected time. It may be indicative of a latching failure or some other critical physical failure that prevents the Droid from being contained within the Aircraft.
This alarm typically signifies that the Aircraft has taken some off-nominal action to attempt to get rid of the unconstrained droid. Depending on the conditions when the alarm is set, the Aircraft may perform one of the following actions (in order of severity):
- Droid Left Behind (Halt >> Winch Lower of Droid >> Line Cut)
- Direct Line Cut (Pause >> Line Cut)
- Paraland
This is a critical alarm that will lead to an off-nominal response.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
did-the-alarm-occur-during-docking-or{"<small><b>Step 1</b></small><br/>Question: Did the alarm occur during docking or..."}
inspect-the-latch-mechanism-and-winch["<small><b>Step 2</b></small><br/>Action: Inspect the latch mechanism and winch..."]
escalate-to-p2-exec-on-call{{"<small><b>Step 3</b></small><br/>Escalation: Escalate to P2 Exec On Call."}}
did-the-alarm-occur-during-docking-or -->|Yes| inspect-the-latch-mechanism-and-winch
did-the-alarm-occur-during-docking-or -->|No| escalate-to-p2-exec-on-call
style did-the-alarm-occur-during-docking-or fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style inspect-the-latch-mechanism-and-winch fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-to-p2-exec-on-call fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
Resolution note
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