Parts · Instruments and avionics

Reference Unit

6 failure reports named the reference unit in the last ten years, 6 since 2017, most often on the Boeing 737; the condition most often found was "failed".

Reports by year

Reports by year, as a table

	reports
2017	1
2018	2
2019	2
2025	1

Which system the reports file it under last ten years

Instruments and avionics6

Reports by system, as a table

	reports
Instruments and avionics	6

Models most often reporting it last ten years

Boeing 7374Bombardier CL-600 Challenger and CRJ1Embraer ERJ 170 E170 and E1751

Models most reported, as a table

	reports
Boeing 737	4
Bombardier CL-600 Challenger and CRJ	1
Embraer ERJ 170 E170 and E175	1

How it failed the condition found, last ten years

failed3faulty3

Conditions found, as a table

	reports
failed	3
faulty	3

Sources: the FAA's service difficulty reports since 1995 (a report is a part that failed and was fixed, as filed by an airline, repair station or owner; the count shows reporting as much as reliability) and the parts manufacturer approvals in the FAA's Dynamic Regulatory System. The part name is the reporters' and the approval holders' own words, reduced to the first plain words so that spellings meet.