0x000300C1 ZIP_EXECUTIVE_CODE_WINCH_LOCK_MECH_NOT_LATCHED
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Applicable alarms (2)
0x000300C1ZIP_EXECUTIVE_CODE_WINCH_LOCK_MECH_NOT_LATCHED
Likely outcomes — click to expand
Based on 0 missions where this alarm fired in the last
90 days
(for 0x000300C1) 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 most common reason for this code is loss-of-comms with components on the docking fin flex (i.e. the flex embedded inside the docking fin that is responsible for reading the latching mechanism, the pulley position, and the fin temperature). Confirmation currently requires looking at logs which means getting a field engineer involved.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
check-lock-mech-state["<small><b>Step 1</b></small><br/>Action: Using the docking fin flex-sensors s..."]
what-is-lock-mech-state-reporting{"<small><b>Step 2</b></small><br/>Question: What is /winch.feedback.lock_mech.lo..."}
issue-is-in-winch-gnc-or-exec{{"<small><b>Step 3</b></small><br/>Escalation: If it has a more typical value of LA..."}}
inspect-for-power-or-comms-issues{{"<small><b>Step 4</b></small><br/>Escalation: If the feedback message isn't present..."}}
plot-docking-fin-flex-signals["<small><b>Step 5</b></small><br/>Action: If /winch.feedback.lock_mech.lock_me..."]
what-data-is-present{"<small><b>Step 6</b></small><br/>Question: What data is present in the plotted d..."}
common-mode-flex-failure["<small><b>Step 7</b></small><br/>Action: If none of the plotted channels have ..."]
likely-lock-mech-magnetometer-damage["<small><b>Step 8</b></small><br/>Action: If data for the docking fin temperatu..."]
if-conditions-not-covered-escalate-firm{{"<small><b>Step 9</b></small><br/>Escalation: If conditions not covered in the abov..."}}
check-lock-mech-state --> what-is-lock-mech-state-reporting
what-is-lock-mech-state-reporting -->|UNKNOWN| plot-docking-fin-flex-signals
what-is-lock-mech-state-reporting -->|LATCHED or UNLATCHED| issue-is-in-winch-gnc-or-exec
what-is-lock-mech-state-reporting -->|Missing or gapped feedback| inspect-for-power-or-comms-issues
plot-docking-fin-flex-signals --> what-data-is-present
what-data-is-present -->|No channels have data| common-mode-flex-failure
what-data-is-present -->|Temperature or pulley data ...| likely-lock-mech-magnetometer-damage
what-data-is-present -->|Other condition| if-conditions-not-covered-escalate-firm
style check-lock-mech-state fill:#dcfce7,stroke:#22c55e,color:#14532d
style what-is-lock-mech-state-reporting fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style issue-is-in-winch-gnc-or-exec fill:#fef3c7,stroke:#f59e0b,color:#78350f
style inspect-for-power-or-comms-issues fill:#fef3c7,stroke:#f59e0b,color:#78350f
style plot-docking-fin-flex-signals fill:#dcfce7,stroke:#22c55e,color:#14532d
style what-data-is-present fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style common-mode-flex-failure fill:#dcfce7,stroke:#22c55e,color:#14532d
style likely-lock-mech-magnetometer-damage fill:#dcfce7,stroke:#22c55e,color:#14532d
style if-conditions-not-covered-escalate-firm fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 action
Using the
docking fin flex-sensors signals template on Barazza, check /winch.feedback.lock_mech.lock_mech_state. 2 question
What is
/winch.feedback.lock_mech.lock_mech_state reporting? 3 escalation
If it has a more typical value of
LATCHED or UNLATCHED, the issue is somewhere in winch GNC or the executive. Escalate to P2 Exec On Call. 4 escalation
If the feedback message isn't present or has large gaps in other fields, such as
/winch.feedback.state.position.theta_m, the winch isn't being powered or there are comms issues. Inspect the aircraft for related issues. Escalate to P2 Firmware Motors On Call if no issues are immediately obvious. 5 action
If
/winch.feedback.lock_mech.lock_mech_state is reporting UNKNOWN, that is the source of the executive code. Plot /winch.feedback.lock_mech.b_lock_mech.x, /winch.feedback.lock_mech.b_lock_mech.y, /winch.feedback.lock_mech.b_lock_mech.z, /winch.temperature_docking_fin, and /winch.debug.winch.theta_pulley_r. All of these signals are derived from sensors on the docking fin flex. 6 question
What data is present in the plotted docking fin flex signals?
7 action
If none of the plotted channels have data, there is likely a common mode failure with the flex.
Check that the flex connector is securely connected to the winch PCB and that the screws holding it on are torqued correctly; see 20.3.2.e Install Double Row Pin Connector. If not, connect, tighten, and retry a mission.
All other possible causes, such as damage to the flex or damage to the winch PCB, require swapping out the docking fin assembly.
Check that the flex connector is securely connected to the winch PCB and that the screws holding it on are torqued correctly; see 20.3.2.e Install Double Row Pin Connector. If not, connect, tighten, and retry a mission.
All other possible causes, such as damage to the flex or damage to the winch PCB, require swapping out the docking fin assembly.
8 action
If data for the docking fin temperature and/or pulley angle is present but the
b_lock_mech channels are empty, there's likely damage to the lock mech magnetometer. This can likely be reworked, but for now swap out the docking fin assembly and escalate to P2 Aircraft Hardware On Call to report that this occurred. 9 escalation
If conditions not covered in the above steps are encountered, escalate to P2 Firmware Platform On Call.
Resolution note
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