A B737-800 was dispatched and rejected takeoff twice due to inertial reference system failure.

Attributes
ACN	531491
Time
Date	200112
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	531491
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : master caution warning other flight crewa other flight crewb
Resolutory Action	flight crew : rejected takeoff
Consequence	other other
Supplementary
Problem Areas	Aircraft Maintenance Human Performance
Primary Problem	Aircraft

Narrative:

On takeoff roll, 'master caution' and 'IRS' illuminated at 30 KTS. No other indications. Aborted takeoff and returned to gate to realign inertials. Completed realignment, maintenance and dispatcher paperwork. Normal push, start, taxi, and takeoff with master caution and ILS illumination at approximately 90 KIAS. Aborted and cleared runway to return to gate. Flight canceled.

Original NASA ASRS Text

Title: A B737-800 WAS DISPATCHED AND REJECTED TKOF TWICE DUE TO INERTIAL REF SYS FAILURE.

Narrative: ON TKOF ROLL, 'MASTER CAUTION' AND 'IRS' ILLUMINATED AT 30 KTS. NO OTHER INDICATIONS. ABORTED TKOF AND RETURNED TO GATE TO REALIGN INERTIALS. COMPLETED REALIGNMENT, MAINT AND DISPATCHER PAPERWORK. NORMAL PUSH, START, TAXI, AND TKOF WITH MASTER CAUTION AND ILS ILLUMINATION AT APPROX 90 KIAS. ABORTED AND CLRED RWY TO RETURN TO GATE. FLT CANCELED.

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.