Narrative:

We were the third crew of the day to fly this aircraft with the multifunction control panel placarded inoperative because the 'climb' button would not illuminate. On provision of the MEL item xx-xx states 'flight crew manually sets required thrust.' maintenance technician and later the captain/manager of the flight operations technical were contacted to ensure this meant to leave the autothrottle system on but not engaged and to manually position the throttles to meet thrust requirements. Once this information was confirmed we departed dfw using manual throttle techniques. On arrival at msp, I contacted maintenance technician to obtain clarification on whether the autothrottles were considered usable in terms of low minimum performance status. The MEL did not state item xx-xx affected the low minimum performance status but did state manual thrust settings would be used. After discussing the matter at great length with technician, it was obvious that this question had never been asked before and a ruling from fokker was required to see if the autothrottles were considered operation but not usable or if they were to be not usable for low minimum performance purposes. Again, the MEL makes no mention of either the autothrottles status of the low minimum performance effect of the use of 'flight crew manually sets required thrust' but MEL does seem to state that autothrottle should not be used even though all autothrottle channels are operative. This ambiguity within the MEL needs to be clarified.

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Original NASA ASRS Text

Title: A FOKKER 100 WAS DISPATCHED WITH THE AUTOTHROTTLES INOP PER THE MEL BUT THE MEL DID NOT ADDRESS THE LOWER MINIMUM PERFORMANCE (CAT II OR CAT III) OF THE ACFT.

Narrative: WE WERE THE THIRD CREW OF THE DAY TO FLY THIS ACFT WITH THE MULTIFUNCTION CTL PANEL PLACARDED INOP BECAUSE THE 'CLB' BUTTON WOULD NOT ILLUMINATE. ON PROVISION OF THE MEL ITEM XX-XX STATES 'FLC MANUALLY SETS REQUIRED THRUST.' MAINT TECHNICIAN AND LATER THE CAPT/MGR OF THE FLT OPS TECHNICAL WERE CONTACTED TO ENSURE THIS MEANT TO LEAVE THE AUTOTHROTTLE SYS ON BUT NOT ENGAGED AND TO MANUALLY POS THE THROTTLES TO MEET THRUST REQUIREMENTS. ONCE THIS INFO WAS CONFIRMED WE DEPARTED DFW USING MANUAL THROTTLE TECHNIQUES. ON ARR AT MSP, I CONTACTED MAINT TECHNICIAN TO OBTAIN CLARIFICATION ON WHETHER THE AUTOTHROTTLES WERE CONSIDERED USABLE IN TERMS OF LOW MINIMUM PERFORMANCE STATUS. THE MEL DID NOT STATE ITEM XX-XX AFFECTED THE LOW MINIMUM PERFORMANCE STATUS BUT DID STATE MANUAL THRUST SETTINGS WOULD BE USED. AFTER DISCUSSING THE MATTER AT GREAT LENGTH WITH TECHNICIAN, IT WAS OBVIOUS THAT THIS QUESTION HAD NEVER BEEN ASKED BEFORE AND A RULING FROM FOKKER WAS REQUIRED TO SEE IF THE AUTOTHROTTLES WERE CONSIDERED OP BUT NOT USABLE OR IF THEY WERE TO BE NOT USABLE FOR LOW MINIMUM PERFORMANCE PURPOSES. AGAIN, THE MEL MAKES NO MENTION OF EITHER THE AUTOTHROTTLES STATUS OF THE LOW MINIMUM PERFORMANCE EFFECT OF THE USE OF 'FLC MANUALLY SETS REQUIRED THRUST' BUT MEL DOES SEEM TO STATE THAT AUTOTHROTTLE SHOULD NOT BE USED EVEN THOUGH ALL AUTOTHROTTLE CHANNELS ARE OPERATIVE. THIS AMBIGUITY WITHIN THE MEL NEEDS TO BE CLARIFIED.

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.