MOTOR_STALLED
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Applicable alarms (1)
MOTOR_STALLED
Likely outcomes — click to expand
Based on 12 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 6 ZERP issues filed on these missions)
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| LONG WING ASM, PORT(LH), ZIP, P2 | 0100553 | 12 |
| LONG WING ASM,STRBRD(RH), ZIP, P2 | 0108493 | 12 |
| CCW HOVER MOTOR ASSY, ZIP, P2 | 19607 | 6 |
| CW EV3 HOVER MOTOR ASSY, ZIP, P2 | 33333 | 6 |
| AFT MOTOR ASSY, ZIP, P2 | 23548 | 4 |
Frequently co-occurring alarms (% of the 12 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”MOTOR_STALLED indicates sustained high torque and low motor speed, consistent with a motor stall. Possible causes include motor damage or an external obstruction preventing normal operation. In some cases, low probability hover motor preflight failures can also manifest as stalls.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
identify-the-affected-motor{"<small><b>Step 1</b></small><br/>Question: What type of motor raised MOTOR_STALLED?"}
did-incident-occur-during-preflight-or-takeoff{"<small><b>Step 2</b></small><br/>Question: Did this incident occur during either..."}
is-this-the-first-occurrence{"<small><b>Step 3</b></small><br/>Question: Is this the first occurrence of this ..."}
likely-startup-failure("<small><b>Step 4</b></small><br/>Reference: This is likely a low probability star...")
inspect-hover-motor["<small><b>Step 5</b></small><br/>Action: Inspect the affected hover motor for ..."]
inspect-mixed-motor["<small><b>Step 6</b></small><br/>Action: Inspect the affected mixed motor for ..."]
was-hover-motor-damage-found{"<small><b>Step 7</b></small><br/>Question: Was damage found on the hover motor?"}
was-mixed-motor-damage-found{"<small><b>Step 8</b></small><br/>Question: Was damage found on the mixed motor?"}
replace-hover-motor["<small><b>Step 9</b></small><br/>Action: Replace the damaged hover motor accor..."]
replace-mixed-motor["<small><b>Step 10</b></small><br/>Action: Replace the damaged mixed motor or af..."]
escalate-to-p2-firmware-motors{{"<small><b>Step 11</b></small><br/>Escalation: Escalate to P2 Firmware Motors On Call."}}
identify-the-affected-motor -->|Servo| escalate-to-p2-firmware-motors
identify-the-affected-motor -->|Hover| did-incident-occur-during-preflight-or-takeoff
identify-the-affected-motor -->|Mixed| inspect-mixed-motor
identify-the-affected-motor -->|Other| escalate-to-p2-firmware-motors
did-incident-occur-during-preflight-or-takeoff -->|Yes| is-this-the-first-occurrence
did-incident-occur-during-preflight-or-takeoff -->|No| inspect-hover-motor
is-this-the-first-occurrence -->|Yes| likely-startup-failure
is-this-the-first-occurrence -->|No| inspect-hover-motor
inspect-hover-motor --> was-hover-motor-damage-found
inspect-mixed-motor --> was-mixed-motor-damage-found
was-hover-motor-damage-found -->|Yes| replace-hover-motor
was-hover-motor-damage-found -->|No| escalate-to-p2-firmware-motors
was-mixed-motor-damage-found -->|Yes| replace-mixed-motor
was-mixed-motor-damage-found -->|No| escalate-to-p2-firmware-motors
style identify-the-affected-motor fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style did-incident-occur-during-preflight-or-takeoff fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style is-this-the-first-occurrence fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style likely-startup-failure fill:#f3e8ff,stroke:#a855f7,color:#581c87
style inspect-hover-motor fill:#dcfce7,stroke:#22c55e,color:#14532d
style inspect-mixed-motor fill:#dcfce7,stroke:#22c55e,color:#14532d
style was-hover-motor-damage-found fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style was-mixed-motor-damage-found fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style replace-hover-motor fill:#dcfce7,stroke:#22c55e,color:#14532d
style replace-mixed-motor fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-to-p2-firmware-motors fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
What type of motor raised MOTOR_STALLED?
2 question
Did this incident occur during either preflight or takeoff?
3 question
Is this the first occurrence of this incident on this motor in consecutive flight attempts?
4 reference
This is likely a low probability startup failure. Follow the Motor Startup Failure guide.
5 action
Inspect the affected hover motor for damage.
- EV2: Inspect Hover Motor - General
- EV3: Inspect Hover Motor
- EV2: Inspect Hover Motor - General
- EV3: Inspect Hover Motor
6 action
Inspect the affected mixed motor for damage.
- EV2: Inspect Mixed Motor
- EV3: Inspect Aft Motor Assembly
- EV2: Inspect Mixed Motor
- EV3: Inspect Aft Motor Assembly
7 question
Was damage found on the hover motor?
8 question
Was damage found on the mixed motor?
9 action
Replace the damaged hover motor according to the applicable UMM procedure. EV2: Remove Hover Motor and Install Hover Motor. EV3: Remove Hover Motor and Install Hover Motor. The aircraft may return to service.
10 action
Replace the damaged mixed motor or aft motor assembly according to the applicable UMM procedure. EV2: Remove Mixed Motor and Install Mixed Motor. EV3: Remove Aft Motor Assembly and Install Aft Motor Assembly. The aircraft may return to service.
11 escalation
Escalate to P2 Firmware Motors On Call.
Resolution note
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