SUSPECT_MISSING_PROPELLER
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Applicable alarms (1)
SUSPECT_MISSING_PROPELLER
Likely outcomes — click to expand
Based on 3 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 2 ZERP issues filed on these missions)
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| BATTERY ASSY, ZIP, P2 | 27158 | 11 |
| SCREW FASTENED, CAMERA MODULE, EV3 | 0110395 | 6 |
| T800 CW HOVER PROPELLER, ZIP, P2 | 31101 | 4 |
| CCW HOVER PROPELLER BLADE, ZIP, P2 | 29857 | 4 |
| CAMERA MODULE ASSEMBLY | 0109600 | 2 |
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”When this alarm triggers, it is likely that we have lost or ejected a propeller in flight.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
choose-alarm-path{"<small><b>Step 1</b></small><br/>Question: Which alarm are you troubleshooting?"}
choose-site-troubleshooting-steps{"<small><b>Step 2</b></small><br/>Question: Which troubleshooting steps do you need?"}
confirm-automatic-incident-tasks["<small><b>Step 3</b></small><br/>Action: The system should automatically compl..."]
commercial-inspect-propeller{"<small><b>Step 4</b></small><br/>Question: Perform a propeller inspection of the..."}
commercial-lost-propeller-type{"<small><b>Step 5</b></small><br/>Question: Contact Powertrain On Call team and r..."}
commercial-mixed-or-hover-propeller["<small><b>Step 6</b></small><br/>Action: Add the relevant WOs to the zip: If t..."]
commercial-droid-thruster-propeller["<small><b>Step 7</b></small><br/>Action: Add the following WO to the zip: Repl..."]
commercial-false-flag["<small><b>Step 8</b></small><br/>Action: Allow Engineering to review logs and ..."]
test-inspect-propeller{"<small><b>Step 9</b></small><br/>Question: Perform a propeller inspection of the..."}
test-lost-propeller-type{"<small><b>Step 10</b></small><br/>Question: Contact Powertrain On Call team and r..."}
test-mixed-or-hover-propeller["<small><b>Step 11</b></small><br/>Action: Add the relevant WOs to the zip: If t..."]
test-droid-thruster-propeller["<small><b>Step 12</b></small><br/>Action: Add the following WO to the zip: Repl..."]
test-false-flag["<small><b>Step 13</b></small><br/>Action: Return the aircraft to service."]
create-a-work-order-to-inspect-the-dro["<small><b>Step 14</b></small><br/>Action: Create a work order to inspect the dr..."]
choose-alarm-path -->|SUSPECT_MISSING_PROPELLER ...| choose-site-troubleshooting-steps
choose-alarm-path -->|SUSPECT_MISSING_PROPELLER ...| create-a-work-order-to-inspect-the-dro
choose-site-troubleshooting-steps -->|Commercial site troubleshoo...| confirm-automatic-incident-tasks
choose-site-troubleshooting-steps -->|Test site troubleshooting s...| test-inspect-propeller
confirm-automatic-incident-tasks --> commercial-inspect-propeller
commercial-inspect-propeller -->|Propeller is confirmed lost| commercial-lost-propeller-type
commercial-inspect-propeller -->|Propeller not lost, alarm i...| commercial-false-flag
commercial-lost-propeller-type -->|Mixed or hover propeller| commercial-mixed-or-hover-propeller
commercial-lost-propeller-type -->|Droid thruster propeller| commercial-droid-thruster-propeller
test-inspect-propeller -->|Propeller is confirmed lost| test-lost-propeller-type
test-inspect-propeller -->|Propeller not lost, alarm i...| test-false-flag
test-lost-propeller-type -->|Mixed or hover propeller| test-mixed-or-hover-propeller
test-lost-propeller-type -->|Droid thruster propeller| test-droid-thruster-propeller
style choose-alarm-path fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style choose-site-troubleshooting-steps fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style confirm-automatic-incident-tasks fill:#dcfce7,stroke:#22c55e,color:#14532d
style commercial-inspect-propeller fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style commercial-lost-propeller-type fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style commercial-mixed-or-hover-propeller fill:#dcfce7,stroke:#22c55e,color:#14532d
style commercial-droid-thruster-propeller fill:#dcfce7,stroke:#22c55e,color:#14532d
style commercial-false-flag fill:#dcfce7,stroke:#22c55e,color:#14532d
style test-inspect-propeller fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style test-lost-propeller-type fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style test-mixed-or-hover-propeller fill:#dcfce7,stroke:#22c55e,color:#14532d
style test-droid-thruster-propeller fill:#dcfce7,stroke:#22c55e,color:#14532d
style test-false-flag fill:#dcfce7,stroke:#22c55e,color:#14532d
style create-a-work-order-to-inspect-the-dro fill:#dcfce7,stroke:#22c55e,color:#14532d Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Which alarm are you troubleshooting?
2 question
Which troubleshooting steps do you need?
3 action
The system should automatically complete the following tasks upon the firing of this alarm. Confirm that they have been completed and, if necessary, complete the tasks and continue to the next step.
- An incident IO channel has been created
- The incident has been escalated to US Flight Operations (@Gene McGuinness) and
@pwt-on-call.
4 question
Perform a propeller inspection of the Aircraft per 60.3.2.a Inspect Hover Propeller - General.
Is the propeller lost?
Is the propeller lost?
5 question
- Contact
@pwt-on-callteam and request the COORDINATE LOCATION of the lost propeller. - Communicate the coordinates to the commercial operations base retrieval team.
- What type of prop is the lost propeller?
6 action
Add the relevant WOs to the zip:
- If the prop was thrown due to a shaft crack, add the following WOs:
- Displace Hover Propeller from Motor (BOM Correction)
- Replace Hover motor on Aircraft
- If the prop was thrown due to a prop pin failure, add the following WOs:
- Inspect Hover Motor Shaft (confirm the bushing and shaft are within damage limits)
- Replace Hover Propeller on Aircraft - (BOM correction)
- If the prop was thrown due to a propeller failure, add the following WOs and file a discrepancy against the damaged prop:
- Inspect Hover Motor Shaft (confirm the bushing and shaft are within damage limits)
- Replace Hover Propeller on Aircraft - (BOM correction)
7 action
Add the following WO to the zip: Replace Main Thruster Assembly on Droid
8 action
Allow Engineering to review logs and return the Aircraft to service.
9 question
Perform a propeller inspection of the Aircraft per 60.3.2.a Inspect Hover Propeller - General.
Is the propeller lost?
Is the propeller lost?
10 question
- Contact
@pwt-on-callteam and request the COORDINATE LOCATION of the lost propeller. - Communicate the coordinates to the test operations retrieval team.
- What type of prop is the lost propeller?
11 action
Add the relevant WOs to the zip:
- If the prop was thrown due to a shaft crack, add the following WOs:
- Displace Hover Propeller from Motor (BOM Correction)
- Replace Hover motor on Aircraft
- If the prop was thrown due to a prop pin failure, add the following WOs:
- Inspect Hover Motor Shaft (confirm the bushing and shaft are within damage limits)
- Replace Hover Propeller on Aircraft - (BOM correction)
- If the prop was thrown due to a propeller failure, add the following WOs and file a discrepancy against the damaged prop:
- Inspect Hover Motor Shaft (confirm the bushing and shaft are within damage limits)
- Replace Hover Propeller on Aircraft - (BOM correction)
12 action
Add the following WO to the zip: Replace Main Thruster Assembly on Droid
13 action
Return the aircraft to service.
14 action
Create a work order to inspect the droid. Replace damaged components as necessary.
- Damage Limits for Droid Foam: Droid CMM 6.5.1.a - Foam Body Damage Limits
- Foam Remove: Droid CMM 10.1.3.d Remove Droid Body Foam
- Foam Install: Droid CMM 10.1.3.e Install Droid Body Foam
- Propeller Replace: Droid CMM 10.1.3.l Replace Mounted Thruster Assembly Components
- Damage Limits for Droid Foam: Droid CMM 6.5.1.a - Foam Body Damage Limits
- Foam Remove: Droid CMM 10.1.3.d Remove Droid Body Foam
- Foam Install: Droid CMM 10.1.3.e Install Droid Body Foam
- Propeller Replace: Droid CMM 10.1.3.l Replace Mounted Thruster Assembly Components
Resolution note
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