Narrative:

Functional check of landing gear proximity switches maintenance work card requires that connectors P0774 and P0775 be removed and reconnected to check nose landing gear door sequence and nose landing gear air-ground (wow) switches in the nose landing gear wheel well. On may/xa/08; I followed those procedures and everything checked out to be ok to the best of my knowledge. But this is done on the ground. I have no way of knowing if the connectors are actually 'correctly' installed since it is in a hard to see area. You connect the connectors by feel since you cannot directly see what you're doing till you're done connecting the connectors. A flashlight and mirror are used to look after the work is done connecting the connectors. You are in an awkward position with hand stretching far into the bulkhead of wheel well to connect the connectors. I learned that another mechanic found the connectors were not connected properly. I will like to suggest that the aircraft be put into flight condition in order to check the uplock wow switches by jacking the aircraft again and doing a gear swing making sure uplock and downlock messages are indicated on the EICAS. Callback conversation with reporter revealed the following information: reporter stated the functional check procedure he performed on the emb-135 nose landing gear proximity switches became an issue after that aircraft required an air turnback after takeoff. There was not any indication in the cockpit; or an EICAS message; showing the nose landing gear was 'up' and 'locked'. Reporter stated he could see the gear was 'down' and 'locked' on the EICAS display after the proximity connectors were reconnected during the functional check; but unless the nose gear was swung; with the aircraft configured in the air mode; there was no way to determine if the 'up' lock connector was properly installed and sending a signal to be displayed on EICAS. Reporter stated he has not received any response to his suggestion to add a nose landing gear swing to the check card in order to verify that an 'uplock' message does appear on EICAS.

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Original NASA ASRS Text

Title: MECHANIC DESCRIBES THE FUNCTIONAL CHECK OF AN EMB-135 NOSE LANDING GEAR PROXIMITY SWITCHES; THAT REQUIRES CONNECTORS TO BE REMOVED AND RECONNECTED WITHOUT AN UPLOCK CHECK OF THE NOSE LNDG GEAR.

Narrative: FUNCTIONAL CHK OF LNDG GEAR PROX SWITCHES MAINT WORK CARD REQUIRES THAT CONNECTORS P0774 AND P0775 BE REMOVED AND RECONNECTED TO CHK NOSE LNDG GEAR DOOR SEQUENCE AND NOSE LNDG GEAR AIR-GND (WOW) SWITCHES IN THE NOSE LNDG GEAR WHEEL WELL. ON MAY/XA/08; I FOLLOWED THOSE PROCS AND EVERYTHING CHKED OUT TO BE OK TO THE BEST OF MY KNOWLEDGE. BUT THIS IS DONE ON THE GND. I HAVE NO WAY OF KNOWING IF THE CONNECTORS ARE ACTUALLY 'CORRECTLY' INSTALLED SINCE IT IS IN A HARD TO SEE AREA. YOU CONNECT THE CONNECTORS BY FEEL SINCE YOU CANNOT DIRECTLY SEE WHAT YOU'RE DOING TILL YOU'RE DONE CONNECTING THE CONNECTORS. A FLASHLIGHT AND MIRROR ARE USED TO LOOK AFTER THE WORK IS DONE CONNECTING THE CONNECTORS. YOU ARE IN AN AWKWARD POS WITH HAND STRETCHING FAR INTO THE BULKHEAD OF WHEEL WELL TO CONNECT THE CONNECTORS. I LEARNED THAT ANOTHER MECH FOUND THE CONNECTORS WERE NOT CONNECTED PROPERLY. I WILL LIKE TO SUGGEST THAT THE ACFT BE PUT INTO FLT CONDITION IN ORDER TO CHK THE UPLOCK WOW SWITCHES BY JACKING THE ACFT AGAIN AND DOING A GEAR SWING MAKING SURE UPLOCK AND DOWNLOCK MESSAGES ARE INDICATED ON THE EICAS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED THE FUNCTIONAL CHECK PROCEDURE HE PERFORMED ON THE EMB-135 NOSE LANDING GEAR PROXIMITY SWITCHES BECAME AN ISSUE AFTER THAT ACFT REQUIRED AN AIR TURNBACK AFTER TAKEOFF. THERE WAS NOT ANY INDICATION IN THE COCKPIT; OR AN EICAS MESSAGE; SHOWING THE NOSE LNDG GEAR WAS 'UP' AND 'LOCKED'. REPORTER STATED HE COULD SEE THE GEAR WAS 'DOWN' AND 'LOCKED' ON THE EICAS DISPLAY AFTER THE PROXIMITY CONNECTORS WERE RECONNECTED DURING THE FUNCTIONAL CHECK; BUT UNLESS THE NOSE GEAR WAS SWUNG; WITH THE ACFT CONFIGURED IN THE AIR MODE; THERE WAS NO WAY TO DETERMINE IF THE 'UP' LOCK CONNECTOR WAS PROPERLY INSTALLED AND SENDING A SIGNAL TO BE DISPLAYED ON EICAS. REPORTER STATED HE HAS NOT RECEIVED ANY RESPONSE TO HIS SUGGESTION TO ADD A NOSE LNDG GEAR SWING TO THE CHECK CARD IN ORDER TO VERIFY THAT AN 'UPLOCK' MESSAGE DOES APPEAR ON EICAS.

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.