ROLL/TILT/MIXED _DISABLED alarm
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Applicable alarms (4)
ROLL_DISABLEDTILT_DISABLEDMIXED_DISABLEDMOTOR_FREEWHEELING_PERMANENTLY
Likely outcomes — click to expand
Based on 106 missions where this alarm fired in the last
90 days
(for ROLL_DISABLED) as of 2026-10-13
Grounding vs discrepancy (of 37 ZERP issues filed on these missions)
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| AFT MOTOR ASSY, PRE-EV2, ZIP, P2 | 23548 | 18 |
| SERVO, ASSY, UNIVERSAL, P2 | 20398 | 11 |
| CW/CCW HOVER MOTOR ASSY, ZIP, P2 | 19607 | 6 |
| PCBA, COATED, TAIL NODE, PRE-EV2, ZIP, P2 | 29407 | 6 |
| CW HOVER MOTOR ASSY, ZIP, P2 | 33333 | 4 |
Frequently co-occurring alarms (% of the 106 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”Either roll or tilt servo lose their calibration, so all roll, tilt, and mixed are disabled together. This is done as a safety precaution.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
was-the-zip-recently-in-diagnostic-mode{"<small><b>Step 1</b></small><br/>Question: Was the Zip recently in diagnostic mo..."}
restart-zip-executive-on-compute-a["<small><b>Step 2</b></small><br/>Action: Stop the Flight Target/procedures/..."]
did-restarting-zip-executive-fix-the-issue{"<small><b>Step 3</b></small><br/>Question: Did restarting the Zip executive serv..."}
in-the-alarm-report-if-the-motor-freew{"<small><b>Step 4</b></small><br/>Question: Was the MOTOR_FREEWHEELING_PERMANENT..."}
replace-the-aft-motor-assembly["<small><b>Step 5</b></small><br/>Action: Replace the Aft Motor Assembly and re..."]
if-not-in-alarm-report-which-site-are-y{"<small><b>Step 6</b></small><br/>Question: Which site are you at?"}
re-attempt-the-mission["<small><b>Step 7</b></small><br/>Action: Re-attempt the mission."]
did-the-mission-pass{"<small><b>Step 8</b></small><br/>Question: Did the mission pass?"}
return-to-service["<small><b>Step 9</b></small><br/>Action: Return to service."]
escalate-to-p2-firmware-motors-on-call{{"<small><b>Step 10</b></small><br/>Escalation: Escalate to P2 Firmware Motors On Call."}}
was-the-zip-recently-in-diagnostic-mode -->|Yes| restart-zip-executive-on-compute-a
was-the-zip-recently-in-diagnostic-mode -->|No| in-the-alarm-report-if-the-motor-freew
restart-zip-executive-on-compute-a --> did-restarting-zip-executive-fix-the-issue
did-restarting-zip-executive-fix-the-issue -->|Yes| return-to-service
did-restarting-zip-executive-fix-the-issue -->|No| in-the-alarm-report-if-the-motor-freew
in-the-alarm-report-if-the-motor-freew -->|Yes| replace-the-aft-motor-assembly
in-the-alarm-report-if-the-motor-freew -->|No| if-not-in-alarm-report-which-site-are-y
if-not-in-alarm-report-which-site-are-y -->|Commercial Site| escalate-to-p2-firmware-motors-on-call
if-not-in-alarm-report-which-site-are-y -->|Test Site| re-attempt-the-mission
re-attempt-the-mission --> did-the-mission-pass
did-the-mission-pass -->|Yes| return-to-service
did-the-mission-pass -->|No| escalate-to-p2-firmware-motors-on-call
style was-the-zip-recently-in-diagnostic-mode fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style restart-zip-executive-on-compute-a fill:#dcfce7,stroke:#22c55e,color:#14532d
style did-restarting-zip-executive-fix-the-issue fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style in-the-alarm-report-if-the-motor-freew fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style replace-the-aft-motor-assembly fill:#dcfce7,stroke:#22c55e,color:#14532d
style if-not-in-alarm-report-which-site-are-y fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style re-attempt-the-mission fill:#dcfce7,stroke:#22c55e,color:#14532d
style did-the-mission-pass fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-to-service fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-to-p2-firmware-motors-on-call fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Was the Zip recently in diagnostic mode for any maintenance actions?
2 action
3 question
Did restarting the Zip executive service fix the issue?
4 question
Was the
MOTOR_FREEWHEELING_PERMANENTLY alarm active on /servo_roll.feedback or /servo_tilt.feedback prior to this alarm setting? 5 action
Replace the Aft Motor Assembly and return to service.
6 question
Which site are you at?
7 action
Re-attempt the mission.
8 question
Did the mission pass?
9 action
Return to service.
10 escalation
Escalate to P2 Firmware Motors On Call.
Resolution note
This plaintext block is ready to paste into the Resolution Note field on the ZERP issue you're working. The permalink below gives engineering review access to the full step-by-step timeline including any back-navigation; share it if the case needs a deeper look.
Permalink:
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