C550, citation jet ii, was released with improper MEL. Inoperative RMI caused an inoperative HSI whi...

Attributes
ACN	367034
Time
Date	199704
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : cmh
State Reference	OH
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : corporate
Make Model Name	Citation II S2/Bravo
Operating Under FAR Part	Part 91
Navigation In Use	Other
Flight Phase	ground : preflight
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 130 flight time total : 4800 flight time type : 600
ASRS Report	367034
Person 2
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : less severe non adherence : far non adherence : published procedure other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

#2 RMI failed in-flight causing failure of heading mode in #1 HSI. After landing at destination, called company maintenance and checked MEL that said RMI can be MEL'ed as long as it is not a repeater of the HSI. Company said it could be MEL'ed, and I concurred so we MEL'ed it and flew it 10 mins VFR back to base with the #1 RMI and #2 HSI still working. Upon returning was told it should not have been MEL'ed. The MEL did not have anything for an HSI, but my thinking was that the RMI's feed the opposite HSI's, and if the RMI can be MEL'ed why can't you fly with only one operable HSI?

Original NASA ASRS Text

Title: C550, CITATION JET II, WAS RELEASED WITH IMPROPER MEL. INOP RMI CAUSED AN INOP HSI WHICH CANNOT BE MEL'ED.

Narrative: #2 RMI FAILED INFLT CAUSING FAILURE OF HEADING MODE IN #1 HSI. AFTER LNDG AT DEST, CALLED COMPANY MAINT AND CHKED MEL THAT SAID RMI CAN BE MEL'ED AS LONG AS IT IS NOT A REPEATER OF THE HSI. COMPANY SAID IT COULD BE MEL'ED, AND I CONCURRED SO WE MEL'ED IT AND FLEW IT 10 MINS VFR BACK TO BASE WITH THE #1 RMI AND #2 HSI STILL WORKING. UPON RETURNING WAS TOLD IT SHOULD NOT HAVE BEEN MEL'ED. THE MEL DID NOT HAVE ANYTHING FOR AN HSI, BUT MY THINKING WAS THAT THE RMI'S FEED THE OPPOSITE HSI'S, AND IF THE RMI CAN BE MEL'ED WHY CAN'T YOU FLY WITH ONLY ONE OPERABLE HSI?

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

C550, citation jet ii, was released with improper MEL. Inoperative RMI caused an inoperative HSI which cannot be MEL'ed.