A B737-200 was released for service after maintenance with the #1 vertical gyro not installed.

Attributes
ACN	501651
Time
Date	200102
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-200
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance ground : parked
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	maintenance : technician
Qualification	technician : airframe technician : powerplant
Experience	maintenance technician : 11
ASRS Report	501651
Person 2
Affiliation	company : air carrier
Function	maintenance : technician
Qualification	technician : powerplant technician : airframe
ASRS Report	501646
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper documentation maintenance problem : improper maintenance non adherence : far non adherence : published procedure
Independent Detector	aircraft equipment other aircraft equipment : adi indicator other other : person 3
Resolutory Action	other
Consequence	other other
Factors
Maintenance	contributing factor : work cards contributing factor : schedule pressure performance deficiency : scheduled maintenance performance deficiency : non compliance with legal requirements performance deficiency : logbook entry performance deficiency : inspection
Supplementary
Problem Areas	Maintenance Human Performance Aircraft
Primary Problem	Maintenance Human Performance

Narrative:

On feb/xa/01, I was assigned aircraft xyz, which had a chronic pressurization problem. In the troubleshooting process, the #1 vertical gyro was removed to facilitate the E1-1 rack removal. When the E1-1 was reinstalled, the #1 vertical gyro was left unsecured. The paperwork showed the rack needed securing but not the gyro -- it was left out. The aircraft was put back together and all noted system disturbed were operations checked. The aircraft was needed for revenue service as soon as possible. Subsequent inspection of east&east compartment missed the gyro and preflight crew also missed it before test flight crew was called in. Our flight crew immediately spotted the problem. Maintenance ordered a new gyro, found the loose one without paperwork noting its removal. Maintenance installed new one and generated all necessary paperwork to properly close paper package for its release back into service.

Original NASA ASRS Text

Title: A B737-200 WAS RELEASED FOR SVC AFTER MAINT WITH THE #1 VERT GYRO NOT INSTALLED.

Narrative: ON FEB/XA/01, I WAS ASSIGNED ACFT XYZ, WHICH HAD A CHRONIC PRESSURIZATION PROB. IN THE TROUBLESHOOTING PROCESS, THE #1 VERT GYRO WAS REMOVED TO FACILITATE THE E1-1 RACK REMOVAL. WHEN THE E1-1 WAS REINSTALLED, THE #1 VERT GYRO WAS LEFT UNSECURED. THE PAPERWORK SHOWED THE RACK NEEDED SECURING BUT NOT THE GYRO -- IT WAS LEFT OUT. THE ACFT WAS PUT BACK TOGETHER AND ALL NOTED SYS DISTURBED WERE OPS CHKED. THE ACFT WAS NEEDED FOR REVENUE SVC ASAP. SUBSEQUENT INSPECTION OF E&E COMPARTMENT MISSED THE GYRO AND PREFLT CREW ALSO MISSED IT BEFORE TEST FLC WAS CALLED IN. OUR FLC IMMEDIATELY SPOTTED THE PROB. MAINT ORDERED A NEW GYRO, FOUND THE LOOSE ONE WITHOUT PAPERWORK NOTING ITS REMOVAL. MAINT INSTALLED NEW ONE AND GENERATED ALL NECESSARY PAPERWORK TO PROPERLY CLOSE PAPER PACKAGE FOR ITS RELEASE BACK INTO SVC.

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.