Two line mechanics report the right forward overwing slide on a B767-300 was inadvertently deployed ...

Narrative:

I received a job assignment to take over from dayshift to verify that the overwing escape slide system was all hooked up and ready to sell to inspection; after a window shade was installed. A couple of other mechanics volunteered to help me as I was not that familiar with the whole process. As we were going through the arming process at the forward overwing right-hand door I heard a small popping noise after the disable handle was moved to the 'armed' position. I did not realize what had just happened at that time. Then we went to the cockpit to test the squibs. The right-hand side would not test. At that point we went outside to take a look and saw that the slide had deployed. Upon further examination afterwards it became apparent that when the disable handle was moved to the 'armed' position; it had moved the auto-arm and auto- fire switches to the 'fire' position. The other three overwing doors disarming handles did not move the switches to the 'fire' position. This switch movement to the 'fire' position by the disarm handle was verified by other personnel.

Original NASA ASRS Text

Title: Two Line Mechanics report the right forward overwing slide on a B767-300 was inadvertently deployed when the disable handle was moved to the 'Armed' position. The disable handle had also moved the auto-arm and auto-fire switches to the 'Fire' position.

Narrative: I received a job assignment to take over from Dayshift to verify that the overwing escape slide system was all hooked up and ready to sell to Inspection; after a window shade was installed. A couple of other Mechanics volunteered to help me as I was not that familiar with the whole process. As we were going through the arming process at the forward overwing right-hand door I heard a small popping noise after the disable handle was moved to the 'Armed' position. I did not realize what had just happened at that time. Then we went to the cockpit to test the squibs. The right-hand side would not test. At that point we went outside to take a look and saw that the slide had deployed. Upon further examination afterwards it became apparent that when the disable handle was moved to the 'Armed' position; it had moved the auto-arm and auto- fire switches to the 'Fire' position. The other three overwing doors disarming handles did not move the switches to the 'Fire' position. This switch movement to the 'Fire' position by the disarm handle was verified by other personnel.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	879402
Time
Date	201003
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Flight Phase	Parked
Component
Aircraft Component	Escape Slide
Person 1
Function	Technician
Qualification	Maintenance Powerplant Maintenance Airframe
Person 2
Function	Technician
Qualification	Maintenance Airframe Maintenance Powerplant
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy

Two line mechanics report the right forward overwing slide on a B767-300 was inadvertently deployed when the disable handle was moved to the 'armed' position. The disable handle had also moved the auto-arm and auto-fire switches to the 'fire' position.