B737-300 flight crew has a rejected takeoff at okc.

Attributes
ACN	721995
Time
Date	200612
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : okc.airport
State Reference	OK
Altitude	agl single value : 0
Environment
Flight Conditions	IMC
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 80 flight time total : 2600 flight time type : 220
ASRS Report	721995
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 128 flight time total : 8900 flight time type : 128
ASRS Report	721996
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : rejected takeoff
Consequence	other
Supplementary
Problem Areas	Flight Crew Human Performance Cabin Crew Human Performance Aircraft
Primary Problem	Cabin Crew Human Performance

Narrative:

Normal preflight; brief and startup for departure. Captain's leg was PF. Began takeoff roll on runway 17R at okc. At around 50 KIAS; a 'whistling/screeching' sound was noticed in the cockpit. Initially; crew thought it was due to possible pressurization sealing at high power. Going through 80 KIAS; noise became increasingly louder and sounded like something was grinding. Between 80-100 KIAS captain initiated rejected takeoff maneuver. Maneuver was performed perfectly with aircraft on centerline; call to flight attendants to remain seated; and tower to roll the trucks for brake inspection. Subsequently; crew cancelled request for emergency vehicles as there were no other indications of a problem; and the noise subsided. Taxied back to the ramp; deplaned; and contacted maintenance control. External inspection of the aircraft provided no indications of problem. Jumpseating flight attendant suggested that it sounded like an audio system malfunction -- which is what it ended up being. Boarding music system had inadvertently switched on with full volume and almost unbearable 'hiss/screech' in the cabin. Maintenance deferred the system and flight proceeded without further incident.

Original NASA ASRS Text

Title: B737-300 FLT CREW HAS A REJECTED TKOF AT OKC.

Narrative: NORMAL PREFLT; BRIEF AND STARTUP FOR DEP. CAPT'S LEG WAS PF. BEGAN TKOF ROLL ON RWY 17R AT OKC. AT AROUND 50 KIAS; A 'WHISTLING/SCREECHING' SOUND WAS NOTICED IN THE COCKPIT. INITIALLY; CREW THOUGHT IT WAS DUE TO POSSIBLE PRESSURIZATION SEALING AT HIGH PWR. GOING THROUGH 80 KIAS; NOISE BECAME INCREASINGLY LOUDER AND SOUNDED LIKE SOMETHING WAS GRINDING. BTWN 80-100 KIAS CAPT INITIATED REJECTED TKOF MANEUVER. MANEUVER WAS PERFORMED PERFECTLY WITH ACFT ON CTRLINE; CALL TO FLT ATTENDANTS TO REMAIN SEATED; AND TWR TO ROLL THE TRUCKS FOR BRAKE INSPECTION. SUBSEQUENTLY; CREW CANCELLED REQUEST FOR EMER VEHICLES AS THERE WERE NO OTHER INDICATIONS OF A PROB; AND THE NOISE SUBSIDED. TAXIED BACK TO THE RAMP; DEPLANED; AND CONTACTED MAINT CTL. EXTERNAL INSPECTION OF THE ACFT PROVIDED NO INDICATIONS OF PROB. JUMPSEATING FLT ATTENDANT SUGGESTED THAT IT SOUNDED LIKE AN AUDIO SYS MALFUNCTION -- WHICH IS WHAT IT ENDED UP BEING. BOARDING MUSIC SYS HAD INADVERTENTLY SWITCHED ON WITH FULL VOLUME AND ALMOST UNBEARABLE 'HISS/SCREECH' IN THE CABIN. MAINT DEFERRED THE SYS AND FLT PROCEEDED WITHOUT FURTHER INCIDENT.

Data retrieved from NASA's ASRS site as of January 2009 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.