Two pilots report about a right engine throttle lever contacting the Throttle Limit Stop Bolt (mechanical stop) on the Center Pedestal of their MD-80 during a Max Power Take-Off selection.
Synopsis
Two pilots report about a right engine throttle lever contacting the Throttle Limit Stop Bolt (mechanical stop) on the Center Pedestal of their MD-80 during a Max Power Take-Off selection.
Narrative
After receiving notice from my base Chief Pilot regarding the maintenance write-up about [MD-80] aircraft takeoff engine indications; this ASRS report is submitted. I was the Captain and pilot flying on the flight. Max Power was selected. All N1 and N2 RPM; Fuel Flow; and EGT for left and right engines were in parameters for Max Take-Off Power. The right EPR was .03 lower than the left engine. EPR is a secondary indication of engine performance. I determined that a safe take-off was being performed and that an abort was not appropriate. I then noted that the right throttle seemed to be at the mechanical limit.I asked the First Officer; pilot not flying; to look at the throttle and its forward limit. At that point he stated the throttle was touching the Throttle Limit Bolt (TLB). All other engine performances throughout the remainder of the flight were normal and as expected. Following the flight; I made a Maintenance Logbook entry with engine performance data focused on the EPR and that the mechanical limit resulting from the bolt had been reached. Based on previous experience; I felt it was unusual that the throttle would meet that bolt [with Max Take-Off selected]. That was the point of the write-up. When the Mechanic arrived at the aircraft; he was confused and didn't know what bolt I had referred to in the Logbook. I took him into the cockpit and showed him the Limit Bolt.
Second reporter narrative
My Captain called and informed me that we should file an ASRS report on the following event:We were re-assigned to fly a flight. The Captain was pilot flying and I was pilot not flying. We made a MAX POWER (PWR) Take-Off (T.O.) and I saw proper indications on N1's and N2's. The right EPR appeared to be slightly off and the throttles were close in alignment.The Captain was setting the power and I noticed that the right throttle was against the [throttle] stop and called it out. Since we had full power on both engines; the Captain elected to continue the Take-Off. During climb; cruise and decent all EPR; N1 and N2 indications were normal.We sent in a [Company] maintenance code and stayed around to talk with Maintenance; on arrival; to be sure they understood the write-up. The Lead Mechanic and the Captain discussed what had occurred; and there seemed to be some misunderstanding by the Mechanic. So; the Captain showed him the cockpit and the Mechanic then understood about the throttle and the [throttle] Screw/Stop.The Captain was concerned about the [right] throttle hitting the Stop with T.O. PWR only; selected. This probably would not be noticed on a Standard (STD) Power T.O. as the power settings are a little lower.
NASA callback
Reporter stated he filed a NASA ASRS report because his Chief Pilot was responding to questions about whether or not he (Reporter) may have knowingly flown an unsafe aircraft. Each throttle has a Throttle Stop Bolt(mechanical limit) at the forward end of the throttle quadrant on the Center Pedestal. Each Stop is adjusted during throttle rig and safety wired. There should be some manual throttle movement available even at the Take-Off selection. Reporter stated the right engine basically matched the left engine and he felt he had adequate power for Take-Off. What he had was a 'Not Normal' condition; a throttle at the Stop was not a criteria for an Abort. On the MD-80's; a 'Reserve' selection is also available which would electronically increase fuel flow to the Fuel Control of the running engine if they were to lose an engine on Take-Off. The 'Reserve ' selection is not affected or controlled by throttle lever position. The Max Take-Off Power selection has enough thrust for one engine operation. He was later informed the procedure he followed was correct. He has over 17;000 hours flying MD-80s.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.