MD80 departing from iah rejected takeoff because of traffic crossing runway downfield.

Attributes
ACN	652963
Time
Date	200504
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : iah.airport
State Reference	TX
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	MD-83
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	ground : taxi
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	652963
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : ground critical incursion : runway non adherence : clearance non adherence : required legal separation
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : took evasive action flight crew : rejected takeoff
Consequence	faa : investigated
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	Ambiguous

Narrative:

Holding short of runway 33R at iah on tower frequency 127.3; we were cleared for takeoff with a 010 degree heading assigned. We initiated a rolling takeoff and soon thereafter we saw an aircraft taxi across the runway ahead of us from west to east on taxiway wl. We aborted at approximately 70 KIAS; informed the tower; and cleared the runway. We queried tower as to why this happened and he stated he didn't know. We heard no clearance for this aircraft to cross our runway. Obviously; we were quite surprised and aggravated. After clearing the runway; we referred to our checklist and determined we were good to go ahead with our flight. The captain only mildly used the brakes and idle reverse. Brake temperature never rose above what it had been taxiing out (100-110 degrees C). The infringing aircraft was well off our runway; appearing to expedite after possibly seeing us heading his way. Before receiving our second takeoff clearance; we again asked tower if he knew what happened. Again; the response was that they didn't know and were trying to find out. We performed our takeoff and flight uneventfully. We never heard a single word from the infringing aircraft and doubt they were even on our frequency. It was a small twin engine bizjet and appeared to have some orange or red flags hanging; leading me to believe it may have been a maintenance repos.

Original NASA ASRS Text

Title: MD80 DEPARTING FROM IAH REJECTED TKOF BECAUSE OF TFC XING RWY DOWNFIELD.

Narrative: HOLDING SHORT OF RWY 33R AT IAH ON TWR FREQ 127.3; WE WERE CLRED FOR TKOF WITH A 010 DEG HDG ASSIGNED. WE INITIATED A ROLLING TKOF AND SOON THEREAFTER WE SAW AN ACFT TAXI ACROSS THE RWY AHEAD OF US FROM W TO E ON TXWY WL. WE ABORTED AT APPROX 70 KIAS; INFORMED THE TWR; AND CLRED THE RWY. WE QUERIED TWR AS TO WHY THIS HAPPENED AND HE STATED HE DIDN'T KNOW. WE HEARD NO CLRNC FOR THIS ACFT TO CROSS OUR RWY. OBVIOUSLY; WE WERE QUITE SURPRISED AND AGGRAVATED. AFTER CLRING THE RWY; WE REFERRED TO OUR CHKLIST AND DETERMINED WE WERE GOOD TO GO AHEAD WITH OUR FLT. THE CAPT ONLY MILDLY USED THE BRAKES AND IDLE REVERSE. BRAKE TEMP NEVER ROSE ABOVE WHAT IT HAD BEEN TAXIING OUT (100-110 DEGS C). THE INFRINGING ACFT WAS WELL OFF OUR RWY; APPEARING TO EXPEDITE AFTER POSSIBLY SEEING US HEADING HIS WAY. BEFORE RECEIVING OUR SECOND TKOF CLRNC; WE AGAIN ASKED TWR IF HE KNEW WHAT HAPPENED. AGAIN; THE RESPONSE WAS THAT THEY DIDN'T KNOW AND WERE TRYING TO FIND OUT. WE PERFORMED OUR TKOF AND FLT UNEVENTFULLY. WE NEVER HEARD A SINGLE WORD FROM THE INFRINGING ACFT AND DOUBT THEY WERE EVEN ON OUR FREQ. IT WAS A SMALL TWIN ENG BIZJET AND APPEARED TO HAVE SOME ORANGE OR RED FLAGS HANGING; LEADING ME TO BELIEVE IT MAY HAVE BEEN A MAINT REPOS.

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.