Narrative:

After completing the stall protection test; the captain notices gust lock lever can be moved to the locked position with the control column full forward. He calls maintenance and they came out; inspected aircraft; and decided to issue MEL. In following the procedure after pulling circuit breakers; one of the steps was to move column full forward and 'ensure locking does not occur.' the gust lock lever was moved to the locked position while the control column was full forward. The control column was not being locked; since there was still full movement of the yoke with the gust lock lever fully engaged but the throttles were restr. The only way to release the gust lock at this point was to push gust lock circuit breaker back in. Mechanic left aircraft and went to speak to his supervisor. They both came back to the aircraft and explained that the 'ensure locking does not occur' part was for the elevator and that in fact the elevator did not lock. They signed off the book and assured us that everything was working the way it should be; and to be careful not to engage the gust lock in-flight. After I returned home; I found an e-mail from the emb fleet manager stating 'gust lock lever cannot be moved with the control column in the forward position. If the gust lock lever can be moved; the MEL must not be applied.' will notify company. Lack of understanding of the system by ZZZ maintenance; and misinterpreting MEL. Better training on system for local maintenance; and interpretation of the MEL; so they will not try to defer items that should not be deferred. Better resources allotted to the pilots. Above e-mail was not available to crew for reference at the time. Most importantly; MEL wording simplified so it is not misinterped; such as the phrasing 'locking should not occur.' that is very vague. Locking of what? The elevator? The thrust levers? The gust lock lever itself? A combination of those 3 items; or all 3 at the same time? Callback conversation with reporter revealed the following information: reporter stated maintenance is using an MEL procedure that allows for the deferral of the gust lock system after verifying the elevator and control column do not lock when the column is pushed forward. Reporter emphasizes the MEL is not only referencing the elevator electro-mechanical lock in the tail; but that the gust lock lever must also not be able to be moved during the test procedure. If the lever does move; then the MEL relief to allow dispatch cannot be used. In other words; if the gust lock lever; on the center pedestal; can be moved; this would be a no-go condition. The gust lock lever on the center pedestal has a connecting rod that attaches to a different lock pin (or safety pin) specifically associated with preventing the movement of the gust lock lever on the pedestal during flight. This is the lock pin that is not locking and is the pin that maintenance does not seem to understand is part of the procedure of what constitutes an unlocked control column and elevator and a secured gust lock lever. If this pin does not lock; then the gust lock lever is not secured in the forward stow position. Therefore; inadvertent aftward movement of this lever is quite possible; resulting in the gust lock lever and attached blocking shaft forcing the throttles aft to almost idle power during any flight condition.

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Original NASA ASRS Text

Title: AN EMB-135 PILOT REPORTS THAT MAINT IS RELEASING ACFT USING AN MEL PROCEDURE TO DEFER THE GUST LOCK SYSTEM WITHOUT ADDRESSING THE ISSUE OF THE GUST LOCK LEVER IN THE COCKPIT WHICH CAN STILL BE MOVED INADVERTENTLY; FORCING THE THROTTLES AFT TO IDLE.

Narrative: AFTER COMPLETING THE STALL PROTECTION TEST; THE CAPT NOTICES GUST LOCK LEVER CAN BE MOVED TO THE LOCKED POS WITH THE CTL COLUMN FULL FORWARD. HE CALLS MAINT AND THEY CAME OUT; INSPECTED ACFT; AND DECIDED TO ISSUE MEL. IN FOLLOWING THE PROC AFTER PULLING CIRCUIT BREAKERS; ONE OF THE STEPS WAS TO MOVE COLUMN FULL FORWARD AND 'ENSURE LOCKING DOES NOT OCCUR.' THE GUST LOCK LEVER WAS MOVED TO THE LOCKED POS WHILE THE CTL COLUMN WAS FULL FORWARD. THE CTL COLUMN WAS NOT BEING LOCKED; SINCE THERE WAS STILL FULL MOVEMENT OF THE YOKE WITH THE GUST LOCK LEVER FULLY ENGAGED BUT THE THROTTLES WERE RESTR. THE ONLY WAY TO RELEASE THE GUST LOCK AT THIS POINT WAS TO PUSH GUST LOCK CIRCUIT BREAKER BACK IN. MECH LEFT ACFT AND WENT TO SPEAK TO HIS SUPVR. THEY BOTH CAME BACK TO THE ACFT AND EXPLAINED THAT THE 'ENSURE LOCKING DOES NOT OCCUR' PART WAS FOR THE ELEVATOR AND THAT IN FACT THE ELEVATOR DID NOT LOCK. THEY SIGNED OFF THE BOOK AND ASSURED US THAT EVERYTHING WAS WORKING THE WAY IT SHOULD BE; AND TO BE CAREFUL NOT TO ENGAGE THE GUST LOCK INFLT. AFTER I RETURNED HOME; I FOUND AN E-MAIL FROM THE EMB FLEET MGR STATING 'GUST LOCK LEVER CANNOT BE MOVED WITH THE CTL COLUMN IN THE FORWARD POS. IF THE GUST LOCK LEVER CAN BE MOVED; THE MEL MUST NOT BE APPLIED.' WILL NOTIFY COMPANY. LACK OF UNDERSTANDING OF THE SYS BY ZZZ MAINT; AND MISINTERPRETING MEL. BETTER TRAINING ON SYS FOR LCL MAINT; AND INTERP OF THE MEL; SO THEY WILL NOT TRY TO DEFER ITEMS THAT SHOULD NOT BE DEFERRED. BETTER RESOURCES ALLOTTED TO THE PLTS. ABOVE E-MAIL WAS NOT AVAILABLE TO CREW FOR REF AT THE TIME. MOST IMPORTANTLY; MEL WORDING SIMPLIFIED SO IT IS NOT MISINTERPED; SUCH AS THE PHRASING 'LOCKING SHOULD NOT OCCUR.' THAT IS VERY VAGUE. LOCKING OF WHAT? THE ELEVATOR? THE THRUST LEVERS? THE GUST LOCK LEVER ITSELF? A COMBINATION OF THOSE 3 ITEMS; OR ALL 3 AT THE SAME TIME? CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED MAINT IS USING AN MEL PROCEDURE THAT ALLOWS FOR THE DEFERRAL OF THE GUST LOCK SYSTEM AFTER VERIFYING THE ELEVATOR AND CONTROL COLUMN DO NOT LOCK WHEN THE COLUMN IS PUSHED FORWARD. REPORTER EMPHASIZES THE MEL IS NOT ONLY REFERENCING THE ELEVATOR ELECTRO-MECHANICAL LOCK IN THE TAIL; BUT THAT THE GUST LOCK LEVER MUST ALSO NOT BE ABLE TO BE MOVED DURING THE TEST PROCEDURE. IF THE LEVER DOES MOVE; THEN THE MEL RELIEF TO ALLOW DISPATCH CANNOT BE USED. IN OTHER WORDS; IF THE GUST LOCK LEVER; ON THE CENTER PEDESTAL; CAN BE MOVED; THIS WOULD BE A NO-GO CONDITION. THE GUST LOCK LEVER ON THE CENTER PEDESTAL HAS A CONNECTING ROD THAT ATTACHES TO A DIFFERENT LOCK PIN (OR SAFETY PIN) SPECIFICALLY ASSOCIATED WITH PREVENTING THE MOVEMENT OF THE GUST LOCK LEVER ON THE PEDESTAL DURING FLIGHT. THIS IS THE LOCK PIN THAT IS NOT LOCKING AND IS THE PIN THAT MAINT DOES NOT SEEM TO UNDERSTAND IS PART OF THE PROCEDURE OF WHAT CONSTITUTES AN UNLOCKED CONTROL COLUMN AND ELEVATOR AND A SECURED GUST LOCK LEVER. IF THIS PIN DOES NOT LOCK; THEN THE GUST LOCK LEVER IS NOT SECURED IN THE FORWARD STOW POSITION. THEREFORE; INADVERTENT AFTWARD MOVEMENT OF THIS LEVER IS QUITE POSSIBLE; RESULTING IN THE GUST LOCK LEVER AND ATTACHED BLOCKING SHAFT FORCING THE THROTTLES AFT TO ALMOST IDLE POWER DURING ANY FLIGHT CONDITION.

Data retrieved from NASA's ASRS site as of January 2009 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.