Narrative:

During climb with engine anti-ice on, wing anti-ice on, and pneumatic xfeed valves open, maximum continuous thrust selected and no mode light illuminated. Later during cruise, it was discovered that with engine and wing anti-ice on and both pneumatic valves closed the no mode light did not illuminate per the operating manual. This discrepancy was entered into the log. I followed up with technician and they indicated that with maximum continuous thrust selected and the airfoil anti-ice on and both pneumatic xfeeds closed you will not get a no mode light. I confirmed that this was true on each and every aircraft that I have checked since. I brought this discrepancy to attention of fleet specialist flight technician. He initially checked it on a simulator and confirmed my findings. After my repeated calls over a 3 month period he informed me that a revision was not pending and he had been told that the operating manual was correct. This does not involve interpretation. It is either right or not. If the operating manual is correct then most, if not all, of the S80 aircraft do not operate properly.

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Original NASA ASRS Text

Title: MD80S ACFT WITH ENG AND WING ANTI-ICE ON AND MAX CONTINUOUS THRUST SELECTED RPTR FO SAYS THAT THE NO MODE LIGHT DIDN'T ILLUMINATE AS IT SHOULD ACCORDING TO THE ACR OPERATING MANUAL.

Narrative: DURING CLB WITH ENG ANTI-ICE ON, WING ANTI-ICE ON, AND PNEUMATIC XFEED VALVES OPEN, MAX CONTINUOUS THRUST SELECTED AND NO MODE LIGHT ILLUMINATED. LATER DURING CRUISE, IT WAS DISCOVERED THAT WITH ENG AND WING ANTI-ICE ON AND BOTH PNEUMATIC VALVES CLOSED THE NO MODE LIGHT DID NOT ILLUMINATE PER THE OPERATING MANUAL. THIS DISCREPANCY WAS ENTERED INTO THE LOG. I FOLLOWED UP WITH TECHNICIAN AND THEY INDICATED THAT WITH MAX CONTINUOUS THRUST SELECTED AND THE AIRFOIL ANTI-ICE ON AND BOTH PNEUMATIC XFEEDS CLOSED YOU WILL NOT GET A NO MODE LIGHT. I CONFIRMED THAT THIS WAS TRUE ON EACH AND EVERY ACFT THAT I HAVE CHKED SINCE. I BROUGHT THIS DISCREPANCY TO ATTN OF FLEET SPECIALIST FLT TECHNICIAN. HE INITIALLY CHKED IT ON A SIMULATOR AND CONFIRMED MY FINDINGS. AFTER MY REPEATED CALLS OVER A 3 MONTH PERIOD HE INFORMED ME THAT A REVISION WAS NOT PENDING AND HE HAD BEEN TOLD THAT THE OPERATING MANUAL WAS CORRECT. THIS DOES NOT INVOLVE INTERP. IT IS EITHER RIGHT OR NOT. IF THE OPERATING MANUAL IS CORRECT THEN MOST, IF NOT ALL, OF THE S80 ACFT DO NOT OPERATE PROPERLY.

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.