Suspect Compute B Air Data Comms Issue
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Applicable alarms (3)
ANGLE_OF_ATTACK_SENSOR_UNRELIABLEANGLE_OF_ATTACK_INPUT_TIMED_OUTVANE_TIMED_OUT
Likely outcomes — click to expand
Based on 90,963 missions where this alarm fired in the last
90 days
(for VANE_TIMED_OUT) as of 2026-10-13
Grounding vs discrepancy (of 1,311 ZERP issues filed on these missions)
Top work orders
- EV3: Inspect Aircraft after Droid Left Behind (DLB) · MAINTENANCE_ACTION 87
- Inspect Droid after Droid Left Behind (DLB) · MAINTENANCE_ACTION 57
- EV3: Replace Wing on Aircraft · MAINTENANCE_ACTION 21
- EV3: Replace Stbd Prepped Hover Harness on Aircraft · MAINTENANCE_ACTION 17
- Troubleshoot Hover Motor Resistance on Aircraft · INSPECTION 14
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| ASSY, SPOOL AND LINE, DOCKING FIN | 48477 | 295 |
| PREPPED HOVER HARNESSING, STBD, ZIP, P2 | 0117583 | 141 |
| CW/CCW HOVER MOTOR ASSY, ZIP, P2 | 19607 | 132 |
| LONG WING ASM, PORT(LH), ZIP, P2 | 0100553 | 127 |
| LONG WING ASSY, DEPOPULATED, STBD (RH), ZIP, P2 | 0108493 | 126 |
Frequently co-occurring alarms (% of the 90,963 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”These alarms indicate an angle-of-attack sensor error or unavailable vane input on Compute B. A persistent communications problem after reboot may indicate a faulty vane flex. Historical VANE_TIMED_OUT can also include invalid values; a timeout alone does not prove a communications failure.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
reboot-vehicle["<small><b>Step 1</b></small><br/>Action: In Fleet Wrangler, open the Aircraft ..."]
run-preflight-after-reboot-b["<small><b>Step 2</b></small><br/>Action: Wait for the reboot mission to comple..."]
is-problem-resolved-after-reboot-b{"<small><b>Step 3</b></small><br/>Question: Did the **Run Health Checks** mission..."}
return-to-service-after-reboot["<small><b>Step 4</b></small><br/>Action: Return the Zip to service."]
replace-vane-or-flex["<small><b>Step 5</b></small><br/>Action: Assign and complete the replacement w..."]
run-preflight-after-replacement["<small><b>Step 6</b></small><br/>Action: After the replacement work order is c..."]
does-preflight-pass-after-replacement{"<small><b>Step 7</b></small><br/>Question: Did the **Run Health Checks** mission..."}
return-to-service-after-replacement["<small><b>Step 8</b></small><br/>Action: Return the Zip to service."]
contact-embedded-linux-oncall{{"<small><b>Step 9</b></small><br/>Escalation: Escalate to P2 Embedded Linux On Call."}}
reboot-vehicle --> run-preflight-after-reboot-b
run-preflight-after-reboot-b --> is-problem-resolved-after-reboot-b
is-problem-resolved-after-reboot-b -->|Yes| return-to-service-after-reboot
is-problem-resolved-after-reboot-b -->|No| replace-vane-or-flex
replace-vane-or-flex --> run-preflight-after-replacement
run-preflight-after-replacement --> does-preflight-pass-after-replacement
does-preflight-pass-after-replacement -->|Yes| return-to-service-after-replacement
does-preflight-pass-after-replacement -->|No| contact-embedded-linux-oncall
style reboot-vehicle fill:#dcfce7,stroke:#22c55e,color:#14532d
style run-preflight-after-reboot-b fill:#dcfce7,stroke:#22c55e,color:#14532d
style is-problem-resolved-after-reboot-b fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-to-service-after-reboot fill:#dcfce7,stroke:#22c55e,color:#14532d
style replace-vane-or-flex fill:#dcfce7,stroke:#22c55e,color:#14532d
style run-preflight-after-replacement fill:#dcfce7,stroke:#22c55e,color:#14532d
style does-preflight-pass-after-replacement fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-to-service-after-replacement fill:#dcfce7,stroke:#22c55e,color:#14532d
style contact-embedded-linux-oncall fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 action
In Fleet Wrangler, open the Aircraft asset view, select Mission Request, choose Reboot Zip (.15+), and click Submit. This reboots both computes and the stowed Droid.
2 action
Wait for the reboot mission to complete. In Fleet Wrangler, select Mission Request, choose Run Health Checks, and click Submit.
3 question
Did the Run Health Checks mission pass with the affected alarm cleared?
4 action
Return the Zip to service.
5 action
Assign and complete the replacement work order for the Aircraft hardware version.
EV2 — replace the angle-of-attack vane
- AoA vane replacement — Work Order Template #38
- Remove Angle of Attack (AoA) Vane
- Install Angle of Attack (AoA) Vane
EV3 — replace the angle-of-attack flex
- AoA harness/flex replacement — Work Order Template #1048
- Remove Angle of Attack (AoA) Flex
- Install Angle of Attack (AoA) Flex
EV2 — replace the angle-of-attack vane
- AoA vane replacement — Work Order Template #38
- Remove Angle of Attack (AoA) Vane
- Install Angle of Attack (AoA) Vane
EV3 — replace the angle-of-attack flex
- AoA harness/flex replacement — Work Order Template #1048
- Remove Angle of Attack (AoA) Flex
- Install Angle of Attack (AoA) Flex
6 action
After the replacement work order is complete, send another Run Health Checks mission from Fleet Wrangler.
7 question
Did the Run Health Checks mission pass with the affected alarm cleared?
8 action
Return the Zip to service.
9 escalation
Escalate to P2 Embedded Linux On Call.
Resolution note
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