Two mechanics did not verify they could arm the cabin door 1-Right escape slide; by installing the g...

Narrative:

Mistakenly left improper length girt bar installed on R-1 door escape slide preventing proper latching of bar in floor mounts during preflight check. Girt bar was replaced before revenue flight. Failed to read and interpret maintenance manual note on girt bar length. Supplemental information from acn 825223: I received a hangar on-routine. The back of the non-routine showed that the part was previously ordered and was in parts room. I checked the part number that was installed with the part number that was ordered. The numbers matched. I then verified the part number effectively for aircraft XXX in the ipc. The new slide came with a girt bar installed. I then printed the aircraft maintenance manual for escape slide and cover removal and installation. I then replaced the escape slide and reinstalled cover with slide on R-1 door. I missed the step in the aircraft maintenance manual that states make sure you can arm the escape slide by installing the girt bar into the floor mounted brackets. I was notified that flight XXX took a delay because the R-1 girt bar was too short and would not latch. The discrepancy was corrected by line maintenance. I was unaware that I could order the correct part number with the correct effectivity but a different size girt bar.

Original NASA ASRS Text

Title: Two Mechanics did not verify they could arm the cabin door 1-Right escape slide; by installing the girt bar into the floor mounted brackets on a B737-800.

Narrative: Mistakenly left improper length girt bar installed on R-1 door escape slide preventing proper latching of bar in floor mounts during preflight check. Girt bar was replaced before revenue flight. Failed to read and interpret Maintenance Manual note on girt bar length. Supplemental information from ACN 825223: I received a hangar on-routine. The back of the non-routine showed that the part was previously ordered and was in parts room. I checked the part number that was installed with the part number that was ordered. The numbers matched. I then verified the part number effectively for Aircraft XXX in the IPC. The new slide came with a girt bar installed. I then printed the Aircraft Maintenance Manual for escape slide and cover removal and installation. I then replaced the escape slide and reinstalled cover with slide on R-1 door. I missed the step in the Aircraft Maintenance Manual that states make sure you can arm the escape slide by installing the girt bar into the floor mounted brackets. I was notified that Flight XXX took a delay because the R-1 girt bar was too short and would not latch. The discrepancy was corrected by Line Maintenance. I was unaware that I could order the correct part number with the correct effectivity but a different size girt bar.

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	825226
Time
Date	200902
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	B737-800
Flight Phase	Parked
Component
Aircraft Component	Escape Slide
Person 1
Function	Technician
Qualification	Maintenance Powerplant Maintenance Inspection Authority Maintenance Airframe
Experience	Maintenance Lead Technician 36
Person 2
Function	Technician
Qualification	Maintenance Powerplant Maintenance Airframe
Experience	Maintenance Technician 10
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Maintenance Deviation - Procedural FAR Deviation - Procedural Published Material / Policy

Two mechanics did not verify they could arm the cabin door 1-Right escape slide; by installing the girt bar into the floor mounted brackets on a B737-800.