A B737-300 was dispatched in non compliance with the incorrect DME interrogator installed.

Attributes
ACN	599518
Time
Date	200311
Day	Wed
Local Time Of Day	1201 To 1800
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	B737-300
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance
Person 1
Affiliation	company : air carrier
Function	maintenance : technician
Qualification	technician : airframe technician : powerplant
ASRS Report	599518
Person 2
Affiliation	company : air carrier
Function	maintenance : technician
Qualification	technician : powerplant technician : airframe
ASRS Report	599517
Events
Anomaly	aircraft equipment problem : critical maintenance problem : non compliance with mel non adherence : published procedure
Independent Detector	aircraft equipment other aircraft equipment : dme flag warning
Resolutory Action	none taken : detected after the fact
Consequence	other other
Factors
Maintenance	contributing factor : schedule pressure performance deficiency : installation performance deficiency : logbook entry performance deficiency : non compliance with legal requirements performance deficiency : repair
Supplementary
Problem Areas	Maintenance Human Performance Chart Or Publication Aircraft
Primary Problem	Maintenance Human Performance

Narrative:

The on duty lead instructed me to assist another mechanic to work aircraft. It was at the gate with #2 DME problem. I pulled an interrogator from stock at the location designated by XXX25. Due to the fact that 4 different interrogators are stocked in the same vicinity, I inadvertently pulled one that was incorrect. It was stocked beside the correct unit. The part number of both units are very close as is the stock location.

Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED IN NON COMPLIANCE WITH THE INCORRECT DME INTERROGATOR INSTALLED.

Narrative: THE ON DUTY LEAD INSTRUCTED ME TO ASSIST ANOTHER MECH TO WORK ACFT. IT WAS AT THE GATE WITH #2 DME PROB. I PULLED AN INTERROGATOR FROM STOCK AT THE LOCATION DESIGNATED BY XXX25. DUE TO THE FACT THAT 4 DIFFERENT INTERROGATORS ARE STOCKED IN THE SAME VICINITY, I INADVERTENTLY PULLED ONE THAT WAS INCORRECT. IT WAS STOCKED BESIDE THE CORRECT UNIT. THE PART NUMBER OF BOTH UNITS ARE VERY CLOSE AS IS THE STOCK LOCATION.

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.