SERVO_*_CALIBRATION: RANGE_INCORRECT
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Applicable alarms (3)
SERVO_ROLL_CALIBRATION: RANGE_INCORRECTSERVO_TILT_CALIBRATION: RANGE_INCORRECTZIP_EXECUTIVE_V4_TEST_RANGE_INCORRECT
Likely outcomes — click to expand
Based on 0 missions where this alarm fired in the last
90 days
(for SERVO_ROLL_CALIBRATION: RANGE_INCORRECT) as of 2026-10-13
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
These troubleshooting steps are applicable to the following alarms:
- SERVO_ROLL_CALIBRATION: RANGE_INCORRECT
- SERVO_TILT_CALIBRATION: RANGE_INCORRECT
Background
Section titled “Background”There could be a problem with the hardstops, mechanism binding/gear friction, or the servos could be plugged in incorrectly if both tilt and roll range are incorrect. Other root causes could be related to power sequencing or timing issues with the larger zip system.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
can-the-issue-be-reproduced-in-diagnos{"<small><b>Step 1</b></small><br/>Question: Can the issue be reproduced in diagno..."}
are-any-other-alarms-present{"<small><b>Step 2</b></small><br/>Question: Are any other alarms present?"}
follow-the-relevant-troubleshooting-to("<small><b>Step 3</b></small><br/>Reference: Follow the relevant troubleshooting t...")
inspect-the-mechanism-are-the-hardstop{"<small><b>Step 4</b></small><br/>Question: Inspect the mechanism. Are the hardst..."}
remove-and-replace-the-roll-tilt-mecha["<small><b>Step 5</b></small><br/>Action: Remove and replace the roll/tilt mech..."]
are-we-reaching-the-hardstop-torque-be{"<small><b>Step 6</b></small><br/>Question: Are we reaching the hardstop torque b..."}
are-there-any-obvious-external-interfe{"<small><b>Step 7</b></small><br/>Question: Are there any obvious external interf..."}
can-the-external-interference-be-remov{"<small><b>Step 8</b></small><br/>Question: Can the external interference be remo..."}
remove-interference-re-run-diagnostic["<small><b>Step 9</b></small><br/>Action: Remove interference, re-run diagnosti..."]
remove-and-replace-the-roll-tilt-mecha-2["<small><b>Step 10</b></small><br/>Action: Remove and replace the roll/tilt mech..."]
this-could-be-an-issue-with-the-mechan["<small><b>Step 11</b></small><br/>Action: This could be an issue with the mecha..."]
did-the-mechanism-move-at-all-during-t{"<small><b>Step 12</b></small><br/>Question: Did the mechanism move at all during ..."}
suspected-deformations-of-the-mechanis["<small><b>Step 13</b></small><br/>Action: Suspected deformations of the mechani..."]
this-could-be-indicative-of-a-connecti["<small><b>Step 14</b></small><br/>Action: This could be indicative of a connect..."]
are-the-tilt-and-roll-servo-connection{"<small><b>Step 15</b></small><br/>Question: Are the tilt and roll servo connectio..."}
hardware-damage-is-suspected-please-re["<small><b>Step 16</b></small><br/>Action: Hardware damage is suspected. Please ..."]
please-correct-the-incorrectly-connec["<small><b>Step 17</b></small><br/>Action: Please correct the incorrectly connec..."]
perform-a-zip-maintenance-health-check{"<small><b>Step 18</b></small><br/>Question: Perform a Zip maintenance health chec..."}
the-aircraft-may-be-returned-to-servic["<small><b>Step 19</b></small><br/>Action: The Aircraft may be returned to service."]
escalate{{"<small><b>Step 20</b></small><br/>Escalation: Escalate."}}
can-the-issue-be-reproduced-in-diagnos -->|Yes| inspect-the-mechanism-are-the-hardstop
can-the-issue-be-reproduced-in-diagnos -->|No| are-any-other-alarms-present
are-any-other-alarms-present -->|Yes| follow-the-relevant-troubleshooting-to
are-any-other-alarms-present -->|No| inspect-the-mechanism-are-the-hardstop
inspect-the-mechanism-are-the-hardstop -->|The hardstops are broken r...| remove-and-replace-the-roll-tilt-mecha
inspect-the-mechanism-are-the-hardstop -->|Mechanism isn't reaching ha...| are-we-reaching-the-hardstop-torque-be
inspect-the-mechanism-are-the-hardstop -->|Are the tilt and roll servo...| are-the-tilt-and-roll-servo-connection
remove-and-replace-the-roll-tilt-mecha --> perform-a-zip-maintenance-health-check
are-we-reaching-the-hardstop-torque-be -->|Yes| are-there-any-obvious-external-interfe
are-we-reaching-the-hardstop-torque-be -->|No| did-the-mechanism-move-at-all-during-t
are-there-any-obvious-external-interfe -->|Yes| can-the-external-interference-be-remov
are-there-any-obvious-external-interfe -->|No| this-could-be-an-issue-with-the-mechan
can-the-external-interference-be-remov -->|Yes| remove-interference-re-run-diagnostic
can-the-external-interference-be-remov -->|No| remove-and-replace-the-roll-tilt-mecha-2
remove-and-replace-the-roll-tilt-mecha-2 --> perform-a-zip-maintenance-health-check
this-could-be-an-issue-with-the-mechan --> perform-a-zip-maintenance-health-check
did-the-mechanism-move-at-all-during-t -->|Yes| suspected-deformations-of-the-mechanis
did-the-mechanism-move-at-all-during-t -->|No| this-could-be-indicative-of-a-connecti
suspected-deformations-of-the-mechanis --> perform-a-zip-maintenance-health-check
this-could-be-indicative-of-a-connecti --> are-the-tilt-and-roll-servo-connection
are-the-tilt-and-roll-servo-connection -->|Yes| hardware-damage-is-suspected-please-re
are-the-tilt-and-roll-servo-connection -->|No| please-correct-the-incorrectly-connec
hardware-damage-is-suspected-please-re --> perform-a-zip-maintenance-health-check
perform-a-zip-maintenance-health-check -->|Yes| the-aircraft-may-be-returned-to-servic
perform-a-zip-maintenance-health-check -->|No| escalate
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style are-we-reaching-the-hardstop-torque-be fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
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style can-the-external-interference-be-remov fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
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style did-the-mechanism-move-at-all-during-t fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style suspected-deformations-of-the-mechanis fill:#dcfce7,stroke:#22c55e,color:#14532d
style this-could-be-indicative-of-a-connecti fill:#dcfce7,stroke:#22c55e,color:#14532d
style are-the-tilt-and-roll-servo-connection fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style hardware-damage-is-suspected-please-re fill:#dcfce7,stroke:#22c55e,color:#14532d
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style escalate fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Can the issue be reproduced in diagnostic mode?
2 question
Are any other alarms present?
3 reference
Follow the relevant troubleshooting topic for the alarm(s).
4 question
Inspect the mechanism.
Are the hardstops intact? Is anything preventing full range of motion (interference of prop with tail, etc)
Are the hardstops intact? Is anything preventing full range of motion (interference of prop with tail, etc)
5 action
Remove and replace the roll/tilt mechanism or AMA.
6 question
Are we reaching the hardstop torque before hitting the hardstop?
7 question
Are there any obvious external interferences?
8 question
Can the external interference be removed?
9 action
Remove interference, re-run diagnostic test and return to step 1 of the guide.
10 action
Remove and replace the roll/tilt mechanism or AMA.
11 action
This could be an issue with the mechanism gearing. Remove and replace the roll/tilt mechanism or AMA.
12 question
Did the mechanism move at all during the diagnostic test?
13 action
Suspected deformations of the mechanism. Please remove and replace the roll/tilt mechanism or AMA.
14 action
This could be indicative of a connection issue or power issue. Please proceed to the next step.
15 question
Are the tilt and roll servo connections to the tail board correct?
16 action
Hardware damage is suspected. Please remove and replace the roll/tilt mechanism or AMA.
17 action
Please correct the incorrectly connected servo connections. Then, return to step 1 of this guide and run the diagnostic mode test.
18 question
Perform a Zip maintenance health check. Is the issue resolved?
19 action
The Aircraft may be returned to service.
20 escalation
Escalate.
Resolution note
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