LATCH_SERVICE_STATE_RETAINED
Applicable alarms (5)
Likely outcomes — click to expand
Based on 0 missions where this alarm fired in the last
90 days
(for LATCH_SERVICE_STATE_RETAINED) as of 2026-10-13
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”The latch service state can be RETAINED if an Aircraft flew into a Dock and the latch service never received a command to retract the Aircraft. The only known cause of this is if the Dock loses power while the Aircraft is docking.
The Dock will not charge the battery or cool the battery in this state and manual intervention is required. A fix is being targeted for .42 for this behavior where the Zip executive will command retract after the mission if it sees that the latch state is retained.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
ssh-into-the-dock["<small><b>Step 1</b></small><br/>Action: SSH into the Dock. For steps, see SS..."]
place-the-dock-into-diagnostic-mode["<small><b>Step 2</b></small><br/>Action: Place the Dock into Diagnostic mode b..."]
run-sudo-systemctl-restart-latch-servic["<small><b>Step 3</b></small><br/>Action: Run: sudo systemctl restart latch.se..."]
look-at-the-dock-s-fleetwrangler-page-i{"<small><b>Step 4</b></small><br/>Question: Look at the Dock’s Fleetwrangler page..."}
place-the-dock-back-into-standard-mode["<small><b>Step 5</b></small><br/>Action: Place the Dock back into Standard mod..."]
the-dock-may-return-to-service("<small><b>Step 6</b></small><br/>Reference: The Dock may return to service.")
place-the-dock-back-into-standard-mode-before-faulted["<small><b>Step 7</b></small><br/>Action: Place the Dock back into Standard mod..."]
follow-latch-service-state-faulted["<small><b>Step 8</b></small><br/>Action: Follow LATCH_SERVICE_STATE_FAULTED..."]
ssh-into-the-dock --> place-the-dock-into-diagnostic-mode
place-the-dock-into-diagnostic-mode --> run-sudo-systemctl-restart-latch-servic
run-sudo-systemctl-restart-latch-servic --> look-at-the-dock-s-fleetwrangler-page-i
look-at-the-dock-s-fleetwrangler-page-i -->|Yes| place-the-dock-back-into-standard-mode
look-at-the-dock-s-fleetwrangler-page-i -->|No| place-the-dock-back-into-standard-mode-before-faulted
place-the-dock-back-into-standard-mode --> the-dock-may-return-to-service
place-the-dock-back-into-standard-mode-before-faulted --> follow-latch-service-state-faulted
style ssh-into-the-dock fill:#dcfce7,stroke:#22c55e,color:#14532d
style place-the-dock-into-diagnostic-mode fill:#dcfce7,stroke:#22c55e,color:#14532d
style run-sudo-systemctl-restart-latch-servic fill:#dcfce7,stroke:#22c55e,color:#14532d
style look-at-the-dock-s-fleetwrangler-page-i fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style place-the-dock-back-into-standard-mode fill:#dcfce7,stroke:#22c55e,color:#14532d
style the-dock-may-return-to-service fill:#f3e8ff,stroke:#a855f7,color:#581c87
style place-the-dock-back-into-standard-mode-before-faulted fill:#dcfce7,stroke:#22c55e,color:#14532d
style follow-latch-service-state-faulted fill:#dcfce7,stroke:#22c55e,color:#14532d Hover or focus a block to preview it. Select the block to keep the preview open.
latch.service. For steps, see Place Dock into Diagnostic Mode (Grounding Dock).Restarting
latch.service outside Diagnostic mode can put the Dock into Degraded Operations Mode.sudo systemctl restart latch.serviceNOTE: Restarting the latch service will NOT drop the Aircraft.
Resolution note
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