Narrative:

A thrust reverser inhibition bolt was not removed by the mechanic after the aircraft thrust reverser was svced; operations checked; and signed off. This bolt was not discovered during the initial walkaround performed by the flight crew. The day began at approximately XA00. Below is the sequence of the day's events: the first officer (me) and the captain performed the first flight of the day walkaround. After this inspection; the captain phoned the maintenance department to verify completion of the maintenance on the #1 thrust reverser because the MEL sticker was still present in the cockpit. The work had been signed off by the mechanic. I performed the postflt walkarounds after the first and second legs and did not notice the thrust reverser bolt. During the landing phase of the third leg; the captain noticed that the #1 thrust reverser did not deploy. After taxiing to the gate; the captain and I discovered the thrust reverser inhibition bolt was still attached to the #1 engine. The location where the thrust reverser inhibition bolts are installed is the bottom of the engines. In order to see if one of the bolts is attached; you must stand directly below the engine and look up. The inspection on the #1 engine is particularly difficult because the baggage door is located under the engine. During the time of a walkaround inspection; baggage and freight is being loaded and unloaded from the baggage compartment. There are ramp personnel; a baggage conveyer; and a tug with baggage carts located under the #1 engine. This is one factor that makes inspection of the bottom of the #1 engine difficult. Another factor that made this particular bolt difficult to see was its color. A thrust reverser inhibition bolt is typically painted. The bolt used for this maintenance event was worn and had lost a lot of the paint on it. Since this event; and in order to avoid a similar situation; I have been paying special attention to whether or not a thrust reverser bolt is installed on either engine. I carefully start my walkaround inspections with a review of the open and recently closed maintenance items on an aircraft. These maintenance items are kept in mind during my inspections. Supplemental information from acn 775902: I flew 3 legs with an aircraft that had been signed off 'operations check good' for a thrust reverser 1 disagreement message to find later in the day that the securing bolt was still installed. I had confirmed the fact that the engine thrust reverser was operable with maintenance control via telephone since I had to call on an unrelated issue. I asked maintenance control the status of the MEL because the mechanic who had worked on the engine left the MEL sticker on the dashboard. I was told by the maintenance controller that the MEL was cleared. The first officer and I both performed a walkaround on the first flight of the day. We were running late due to a scheduling error with the hotel van; then incorrect directions to our gate once we got to iad. We did our preflight checks thoroughly but expeditiously and neither one of us noticed it. The first officer did the remaining walkaround checks until I noticed it on landing later that day. Some of the contributing factors were that we were hurrying to get the aircraft underway; the presence of a belt-loader and baggage loading in the cargo compartment; and IMC/rainy/snowy conditions at the time. It should be noted that to see the thrust reverser restraining bolt on the thrust reversers you almost have to be standing under the engine looking straight up; an especially difficult thing to accomplish with the bag loader and ground personnel loading bags. It was also either raining or snowing while we were flying all that day which definitely distraction from being able to properly see that area because you would get either snow or rain in your eyes. Another contributing factor was that the securing bolt was very well used and while typically brightly painted; this bolt was mostly a color which blended into the color of the engine. I will pay special attention to areas that have been MEL'ed and since cleared when I do visual inspections in the future. Callback conversation with reporter acn 775900 revealed the following information: reporter stated their normal procedure is to pull the trigger at the base of the thrust levers to deploy the reverser clamshell doors on the engines; while applying brake pedals using the carbon fiber brakes. Most times; unless a short runway; pilots would not increase reverse thrust because of the effectiveness of the carbon fiber brakes. As a result; they did not notice any adverse yaw even though only one reverser had deployed. Reporter stated his carrier had contract maintenance working on the #1 engine reverser the night before and all the paperwork was signed-off; including a maintenance sign-off stating reverser operations checks 'ok.' yet; no one has been able to answer his question that; with the thrust reverser inhibition bolt still installed; how could the reverser operations check be 'ok'?

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Original NASA ASRS Text

Title: AN ERJ-145 (EMB-145) FLIGHT CREW DISCOVERS A THRUST REVERSER INHIBITION BOLT FOR #1 ENG NOT REMOVED BY MAINT EVEN THOUGH MECHANIC SIGNED-OFF PAPERWORK. PAINT IDENTIFIER ON BOLT HEAD WORN OFF; NOT EASILY SEEN.

Narrative: A THRUST REVERSER INHIBITION BOLT WAS NOT REMOVED BY THE MECH AFTER THE ACFT THRUST REVERSER WAS SVCED; OPS CHKED; AND SIGNED OFF. THIS BOLT WAS NOT DISCOVERED DURING THE INITIAL WALKAROUND PERFORMED BY THE FLT CREW. THE DAY BEGAN AT APPROX XA00. BELOW IS THE SEQUENCE OF THE DAY'S EVENTS: THE FO (ME) AND THE CAPT PERFORMED THE FIRST FLT OF THE DAY WALKAROUND. AFTER THIS INSPECTION; THE CAPT PHONED THE MAINT DEPT TO VERIFY COMPLETION OF THE MAINT ON THE #1 THRUST REVERSER BECAUSE THE MEL STICKER WAS STILL PRESENT IN THE COCKPIT. THE WORK HAD BEEN SIGNED OFF BY THE MECH. I PERFORMED THE POSTFLT WALKAROUNDS AFTER THE FIRST AND SECOND LEGS AND DID NOT NOTICE THE THRUST REVERSER BOLT. DURING THE LNDG PHASE OF THE THIRD LEG; THE CAPT NOTICED THAT THE #1 THRUST REVERSER DID NOT DEPLOY. AFTER TAXIING TO THE GATE; THE CAPT AND I DISCOVERED THE THRUST REVERSER INHIBITION BOLT WAS STILL ATTACHED TO THE #1 ENG. THE LOCATION WHERE THE THRUST REVERSER INHIBITION BOLTS ARE INSTALLED IS THE BOTTOM OF THE ENGS. IN ORDER TO SEE IF ONE OF THE BOLTS IS ATTACHED; YOU MUST STAND DIRECTLY BELOW THE ENG AND LOOK UP. THE INSPECTION ON THE #1 ENG IS PARTICULARLY DIFFICULT BECAUSE THE BAGGAGE DOOR IS LOCATED UNDER THE ENG. DURING THE TIME OF A WALKAROUND INSPECTION; BAGGAGE AND FREIGHT IS BEING LOADED AND UNLOADED FROM THE BAGGAGE COMPARTMENT. THERE ARE RAMP PERSONNEL; A BAGGAGE CONVEYER; AND A TUG WITH BAGGAGE CARTS LOCATED UNDER THE #1 ENG. THIS IS ONE FACTOR THAT MAKES INSPECTION OF THE BOTTOM OF THE #1 ENG DIFFICULT. ANOTHER FACTOR THAT MADE THIS PARTICULAR BOLT DIFFICULT TO SEE WAS ITS COLOR. A THRUST REVERSER INHIBITION BOLT IS TYPICALLY PAINTED. THE BOLT USED FOR THIS MAINT EVENT WAS WORN AND HAD LOST A LOT OF THE PAINT ON IT. SINCE THIS EVENT; AND IN ORDER TO AVOID A SIMILAR SITUATION; I HAVE BEEN PAYING SPECIAL ATTN TO WHETHER OR NOT A THRUST REVERSER BOLT IS INSTALLED ON EITHER ENG. I CAREFULLY START MY WALKAROUND INSPECTIONS WITH A REVIEW OF THE OPEN AND RECENTLY CLOSED MAINT ITEMS ON AN ACFT. THESE MAINT ITEMS ARE KEPT IN MIND DURING MY INSPECTIONS. SUPPLEMENTAL INFO FROM ACN 775902: I FLEW 3 LEGS WITH AN ACFT THAT HAD BEEN SIGNED OFF 'OPS CHK GOOD' FOR A THRUST REVERSER 1 DISAGREEMENT MESSAGE TO FIND LATER IN THE DAY THAT THE SECURING BOLT WAS STILL INSTALLED. I HAD CONFIRMED THE FACT THAT THE ENG THRUST REVERSER WAS OPERABLE WITH MAINT CTL VIA TELEPHONE SINCE I HAD TO CALL ON AN UNRELATED ISSUE. I ASKED MAINT CTL THE STATUS OF THE MEL BECAUSE THE MECH WHO HAD WORKED ON THE ENG LEFT THE MEL STICKER ON THE DASHBOARD. I WAS TOLD BY THE MAINT CTLR THAT THE MEL WAS CLRED. THE FO AND I BOTH PERFORMED A WALKAROUND ON THE FIRST FLT OF THE DAY. WE WERE RUNNING LATE DUE TO A SCHEDULING ERROR WITH THE HOTEL VAN; THEN INCORRECT DIRECTIONS TO OUR GATE ONCE WE GOT TO IAD. WE DID OUR PREFLT CHKS THOROUGHLY BUT EXPEDITIOUSLY AND NEITHER ONE OF US NOTICED IT. THE FO DID THE REMAINING WALKAROUND CHKS UNTIL I NOTICED IT ON LNDG LATER THAT DAY. SOME OF THE CONTRIBUTING FACTORS WERE THAT WE WERE HURRYING TO GET THE ACFT UNDERWAY; THE PRESENCE OF A BELT-LOADER AND BAGGAGE LOADING IN THE CARGO COMPARTMENT; AND IMC/RAINY/SNOWY CONDITIONS AT THE TIME. IT SHOULD BE NOTED THAT TO SEE THE THRUST REVERSER RESTRAINING BOLT ON THE THRUST REVERSERS YOU ALMOST HAVE TO BE STANDING UNDER THE ENG LOOKING STRAIGHT UP; AN ESPECIALLY DIFFICULT THING TO ACCOMPLISH WITH THE BAG LOADER AND GND PERSONNEL LOADING BAGS. IT WAS ALSO EITHER RAINING OR SNOWING WHILE WE WERE FLYING ALL THAT DAY WHICH DEFINITELY DISTR FROM BEING ABLE TO PROPERLY SEE THAT AREA BECAUSE YOU WOULD GET EITHER SNOW OR RAIN IN YOUR EYES. ANOTHER CONTRIBUTING FACTOR WAS THAT THE SECURING BOLT WAS VERY WELL USED AND WHILE TYPICALLY BRIGHTLY PAINTED; THIS BOLT WAS MOSTLY A COLOR WHICH BLENDED INTO THE COLOR OF THE ENG. I WILL PAY SPECIAL ATTN TO AREAS THAT HAVE BEEN MEL'ED AND SINCE CLRED WHEN I DO VISUAL INSPECTIONS IN THE FUTURE. CALLBACK CONVERSATION WITH RPTR ACN 775900 REVEALED THE FOLLOWING INFO: REPORTER STATED THEIR NORMAL PROCEDURE IS TO PULL THE TRIGGER AT THE BASE OF THE THRUST LEVERS TO DEPLOY THE REVERSER CLAMSHELL DOORS ON THE ENGINES; WHILE APPLYING BRAKE PEDALS USING THE CARBON FIBER BRAKES. MOST TIMES; UNLESS A SHORT RUNWAY; PILOTS WOULD NOT INCREASE REVERSE THRUST BECAUSE OF THE EFFECTIVENESS OF THE CARBON FIBER BRAKES. AS A RESULT; THEY DID NOT NOTICE ANY ADVERSE YAW EVEN THOUGH ONLY ONE REVERSER HAD DEPLOYED. REPORTER STATED HIS CARRIER HAD CONTRACT MAINT WORKING ON THE #1 ENG REVERSER THE NIGHT BEFORE AND ALL THE PAPERWORK WAS SIGNED-OFF; INCLUDING A MAINT SIGN-OFF STATING REVERSER OPS CHECKS 'OK.' YET; NO ONE HAS BEEN ABLE TO ANSWER HIS QUESTION THAT; WITH THE THRUST REVERSER INHIBITION BOLT STILL INSTALLED; HOW COULD THE REVERSER OPS CHECK BE 'OK'?

Data retrieved from NASA's ASRS site as of May 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.