ADSB_NOT_READY
Viewing this guide for
Applicable alarms (2)
ADSB_NOT_READYADSB_MODULE_NOT_READY
Likely outcomes — click to expand
Based on 869,699 missions where this alarm fired in the last
90 days
(for ADSB_MODULE_NOT_READY) as of 2026-10-13
Grounding vs discrepancy (of 5,773 ZERP issues filed on these missions)
Top work orders
- EV3: Inspect Aircraft after Droid Left Behind (DLB) · MAINTENANCE_ACTION 215
- Troubleshoot Hover Motor Resistance on Aircraft · INSPECTION 77
- EV2: Troubleshoot Electrical Contacts on Aircraft and Droid · INSPECTION 71
- Reset Droid Lid · TROUBLESHOOTING 57
- EV2: ZCO-2026-08-03 Lower Foam Wear Pad Retrofit (FRCO-286 / SB-2026-023) · UPGRADE_RETROFIT 35
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| SERVO, ASSY, UNIVERSAL, P2 | 20398 | 983 |
| CW/CCW HOVER MOTOR ASSY, ZIP, P2 | 19607 | 822 |
| ASSY, SPOOL AND LINE, DOCKING FIN, AIRCRAFT, P2 | 48477 | 782 |
| PRE-PREG TAIL ASSY STBD(RH), ZIP, P2 | 21840 | 684 |
| TAIL PORT DEPOP, ZIP, P2 | 31280 | 651 |
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”ADSB constantly streaming available detection data is absolutely necessary for the functioning of the cooperative DAA system. Each compute has its own ADSB device. This alarm being set will block flight or trigger a dockAsap if it happens during flight.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
is-the-aircraft-preflight-or-in-flight{"<small><b>Step 1</b></small><br/>Question: Is the aircraft preflight or in-flight?"}
does-alarm-clear-on-its-own{"<small><b>Step 2</b></small><br/>Question: Does alarm clear on its own?"}
return-aircraft-to-service-no-ticket-ne["<small><b>Step 3</b></small><br/>Action: Return aircraft to service. No ticket..."]
has-this-persisted-after-two-power-cycles{"<small><b>Step 4</b></small><br/>Question: Has the Aircraft already completed th..."}
perform-the-troubleshooting-steps-in("<small><b>Step 5</b></small><br/>Reference: Perform the troubleshooting steps in ...")
replace-adsb-device-or-compute("<small><b>Step 6</b></small><br/>Reference: The ADSB device is still not working ...")
zip-aircraft-returns-to-dock["<small><b>Step 7</b></small><br/>Action: Zip aircraft returns to dock."]
does-alarm-clear-on-its-own-2{"<small><b>Step 8</b></small><br/>Question: Does alarm clear on its own?"}
return-aircraft-to-service-no-ticket-ne-2["<small><b>Step 9</b></small><br/>Action: Return aircraft to service. No ticket..."]
has-this-persisted-after-two-power-cycles-2{"<small><b>Step 10</b></small><br/>Question: Has the Aircraft already completed th..."}
perform-the-troubleshooting-steps-in-2("<small><b>Step 11</b></small><br/>Reference: Perform the troubleshooting steps in ...")
replace-adsb-device-or-compute-2("<small><b>Step 12</b></small><br/>Reference: The ADSB device is still not working ...")
is-the-aircraft-preflight-or-in-flight -->|Preflight| does-alarm-clear-on-its-own
is-the-aircraft-preflight-or-in-flight -->|In-flight| zip-aircraft-returns-to-dock
does-alarm-clear-on-its-own -->|Yes| return-aircraft-to-service-no-ticket-ne
does-alarm-clear-on-its-own -->|No| has-this-persisted-after-two-power-cycles
has-this-persisted-after-two-power-cycles -->|Yes| replace-adsb-device-or-compute
has-this-persisted-after-two-power-cycles -->|No| perform-the-troubleshooting-steps-in
zip-aircraft-returns-to-dock --> does-alarm-clear-on-its-own-2
does-alarm-clear-on-its-own-2 -->|Yes| return-aircraft-to-service-no-ticket-ne-2
does-alarm-clear-on-its-own-2 -->|No| has-this-persisted-after-two-power-cycles-2
has-this-persisted-after-two-power-cycles-2 -->|Yes| replace-adsb-device-or-compute-2
has-this-persisted-after-two-power-cycles-2 -->|No| perform-the-troubleshooting-steps-in-2
style is-the-aircraft-preflight-or-in-flight fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style does-alarm-clear-on-its-own fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-aircraft-to-service-no-ticket-ne fill:#dcfce7,stroke:#22c55e,color:#14532d
style has-this-persisted-after-two-power-cycles fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style perform-the-troubleshooting-steps-in fill:#f3e8ff,stroke:#a855f7,color:#581c87
style replace-adsb-device-or-compute fill:#f3e8ff,stroke:#a855f7,color:#581c87
style zip-aircraft-returns-to-dock fill:#dcfce7,stroke:#22c55e,color:#14532d
style does-alarm-clear-on-its-own-2 fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-aircraft-to-service-no-ticket-ne-2 fill:#dcfce7,stroke:#22c55e,color:#14532d
style has-this-persisted-after-two-power-cycles-2 fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style perform-the-troubleshooting-steps-in-2 fill:#f3e8ff,stroke:#a855f7,color:#581c87
style replace-adsb-device-or-compute-2 fill:#f3e8ff,stroke:#a855f7,color:#581c87 Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Is the aircraft preflight or in-flight?
2 question
Does alarm clear on its own?
3 action
Return aircraft to service. No ticket necessary.
4 question
Has the Aircraft already completed the power-cycle troubleshooting in the ADSB_MODULE_NOT_READY guide for this same event, and is
ADSB_NOT_READY or ADSB_MODULE_NOT_READY still present? 5 reference
Perform the troubleshooting steps in the ADSB_MODULE_NOT_READY guide. That guide contains the Aircraft power-cycle step and links to the power-cycle procedure.
6 reference
The ADSB device is still not working after repeated reboots. Go to the Replace the compute board step in the ADSB_MODULE_NOT_READY guide.
7 action
Zip aircraft returns to dock.
8 question
Does alarm clear on its own?
9 action
Return aircraft to service. No ticket necessary.
10 question
Has the Aircraft already completed the power-cycle troubleshooting in the ADSB_MODULE_NOT_READY guide for this same event, and is
ADSB_NOT_READY or ADSB_MODULE_NOT_READY still present? 11 reference
Perform the troubleshooting steps in the ADSB_MODULE_NOT_READY guide. That guide contains the Aircraft power-cycle step and links to the power-cycle procedure.
12 reference
The ADSB device is still not working after repeated reboots. Go to the Replace the compute board step in the ADSB_MODULE_NOT_READY guide.
Resolution note
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