CELL_MODEM_HARDWARE_FAILURE (Zip)
Applicable alarms (1)
Likely outcomes — click to expand
Based on 32 missions where this alarm fired in the last 90 days as of 2026-10-13
Frequently co-occurring alarms (% of the 32 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm is set if we fail to connect to the cellular modem on one of the Aircraft compute boards or the Dock.
Troubleshooting Steps for Zip
Section titled “Troubleshooting Steps for Zip”graph TD
power-cycle-the-aircraft-power-cycle-ai["<small><b>Step 1</b></small><br/>Action: Power cycle the Aircraft Power Cycle..."]
perform-preflight["<small><b>Step 2</b></small><br/>Action: Perform preflight."]
has-the-alarm-cleared{"<small><b>Step 3</b></small><br/>Question: Has the alarm cleared?"}
return-the-aircraft-to-service("<small><b>Step 4</b></small><br/>Reference: Return the Aircraft to service")
take-note-of-which-compute-board-the-al["<small><b>Step 5</b></small><br/>Action: Take note of which compute board the ..."]
replace-the-compute-board["<small><b>Step 6</b></small><br/>Action: Replace the compute board a. UMM: Rem..."]
did-this-remedy-the-issue{"<small><b>Step 7</b></small><br/>Question: Did this remedy the issue?"}
return-the-aircraft-to-service-2("<small><b>Step 8</b></small><br/>Reference: Return the Aircraft to service")
escalate-to-embedded-linux{{"<small><b>Step 9</b></small><br/>Escalation: Escalate to Embedded Linux"}}
power-cycle-the-aircraft-power-cycle-ai --> perform-preflight
perform-preflight --> has-the-alarm-cleared
has-the-alarm-cleared -->|Yes| return-the-aircraft-to-service
has-the-alarm-cleared -->|No| take-note-of-which-compute-board-the-al
take-note-of-which-compute-board-the-al --> replace-the-compute-board
replace-the-compute-board --> did-this-remedy-the-issue
did-this-remedy-the-issue -->|Yes| return-the-aircraft-to-service-2
did-this-remedy-the-issue -->|No| escalate-to-embedded-linux
style power-cycle-the-aircraft-power-cycle-ai fill:#dcfce7,stroke:#22c55e,color:#14532d
style perform-preflight fill:#dcfce7,stroke:#22c55e,color:#14532d
style has-the-alarm-cleared fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-the-aircraft-to-service fill:#f3e8ff,stroke:#a855f7,color:#581c87
style take-note-of-which-compute-board-the-al fill:#dcfce7,stroke:#22c55e,color:#14532d
style replace-the-compute-board fill:#dcfce7,stroke:#22c55e,color:#14532d
style did-this-remedy-the-issue fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-the-aircraft-to-service-2 fill:#f3e8ff,stroke:#a855f7,color:#581c87
style escalate-to-embedded-linux fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
a. UMM: Remove Flight Compute Assembly
b. UMM: Install Flight Compute Assembly
Resolution note
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