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Thread: A320 RAIM Check
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Old 27th Apr 2021, 02:43
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Qwark
 
Join Date: Dec 2019
Location: SS Enterprise
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Here's my take:
The big problem is Airbus don't specifically use the term RAIM in their documents (not much anyway)

This is a quote from our FCOM;
"When in IRS/GPS made, the GPS PRIMARY status combines two different criteria:
- The accuracy criterion (HIGH / LOW accuracy)
- The integrity criterion: This is the capability to detect a failure and provide appropriate warning of it."

Additionally
"If the GPS data does not comply with an integrity criterion that is based on a Horizontal Integrity Limit (HIL) and on the automatic detection of failed satellites, the FMS rejects the GPS mode and uses the radio position update"

I have always interpreted the "detection of failed satellites" as a loss of RAIM.
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