A B737 during maintenance had the nose landing gear inadvertently retracted.

Attributes
ACN	347079
Time
Date	199609
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : zzz
State Reference	US
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Light	Night
Aircraft 1
Controlling Facilities	tower : dfw
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
ASRS Report	347079
Person 2
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
Events
Anomaly	aircraft equipment problem : critical non adherence : published procedure non adherence : far other anomaly other
Independent Detector	other other : unspecified
Resolutory Action	other
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

During routine medium large transport strut seal change, hydraulics were used to break down locks on left main landing gear, other gears were pinned. Upon completion, only brakes needed to be bled. Gear pins removed by a second mechanic. A third mechanic went into cockpit to bleed brakes. As pumps were turned on nose landing gear collapsed. I was put on suspension because I was the mechanic who initially retracted medium large transport and left gear handle in retract position. Reasoning for gear handle left in retract position: to ease in manual retraction upon installation of strut (big mistake.) ground interconnect to pressurize 'a' system was manually set and cannon plug removed to initially break down lock was not reset also.

Original NASA ASRS Text

Title: A B737 DURING MAINT HAD THE NOSE LNDG GEAR INADVERTENTLY RETRACTED.

Narrative: DURING ROUTINE MLG STRUT SEAL CHANGE, HYDS WERE USED TO BREAK DOWN LOCKS ON L MAIN LNDG GEAR, OTHER GEARS WERE PINNED. UPON COMPLETION, ONLY BRAKES NEEDED TO BE BLED. GEAR PINS REMOVED BY A SECOND MECH. A THIRD MECH WENT INTO COCKPIT TO BLEED BRAKES. AS PUMPS WERE TURNED ON NOSE LNDG GEAR COLLAPSED. I WAS PUT ON SUSPENSION BECAUSE I WAS THE MECH WHO INITIALLY RETRACTED MLG AND L GEAR HANDLE IN RETRACT POS. REASONING FOR GEAR HANDLE LEFT IN RETRACT POS: TO EASE IN MANUAL RETRACTION UPON INSTALLATION OF STRUT (BIG MISTAKE.) GND INTERCONNECT TO PRESSURIZE 'A' SYS WAS MANUALLY SET AND CANNON PLUG REMOVED TO INITIALLY BREAK DOWN LOCK WAS NOT RESET ALSO.

Data retrieved from NASA's ASRS site as of July 2007 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.