Air carrier widebody transport hit patches of snow and slush on takeoff from ord causing damage to a...

Attributes
ACN	172982
Time
Date	199103
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ord
State Reference	IL
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : ord
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	climbout : takeoff
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 16000 flight time type : 300
ASRS Report	172982
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : less severe inflight encounter other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted none taken : detected after the fact
Consequence	other
Supplementary
Primary Problem	Airport
Air Traffic Incident	other
Situations
Airport	other physical facility

Narrative:

Cleared for takeoff on runway 32R at ord we began our takeoff roll. As we reached 100-120 KTS we encountered a patch of what appeared to be dry snow laying across the runway. It was about 100-150' long and I noticed a slight amount of drag as we went through the patch. Just prior to rotation we went through another similar patch. As we were lifting off I noticed what was probably a similar patch of snow (slush) on the last 1000' of the runway and I remember thinking I was glad I didn't have to abort in that situation. After switching to departure I asked them to pass along a message to tower about the runway condition. They told me they were too busy, and to switch back and give them the message myself. I tried, but there was constant communication on the frequency so I went back to work with center. Rest of trip and landing were uneventful. On arrival at stockholm the out-going crew discovered damage to the brake heatshields and an anti-skid cable. As a result all four rear wheels on the aircraft had to be changed. They also couldn't get the cargo door open west/O applying heat to melt the frozen slush in the door tracks. I think the appearance of patches of snow was deceptive. It is possible the patches had been treated with something causing them to partially melt and refreeze thus making them particularly bad. I don't see where just a patch of packed snow is that big a problem on an otherwise dry runway. During the takeoff roll I was especially alert to any indications of ice or snow ingestion in the engines thinking I would immediately abort if there were any such indications, however having none I continued the takeoff. In retrospect I think I should have aborted at the first sign of the patches being other than just packed snow. All this in spite of the fact we were on an exceptionally long runway. Also I think we were the first to takeoff on that runway after it had been opened. If this were truly the case it would have been nice to have been so notified by the tower.

Original NASA ASRS Text

Title: ACR WDB HIT PATCHES OF SNOW AND SLUSH ON TKOF FROM ORD CAUSING DAMAGE TO A BRAKE HEAT SHIELD AND AN ANTISKID CABLE. DAMAGE NOT DISCOVERED UNTIL POSTFLT INSPECTION AT DESTINATION.

Narrative: CLRED FOR TKOF ON RWY 32R AT ORD WE BEGAN OUR TKOF ROLL. AS WE REACHED 100-120 KTS WE ENCOUNTERED A PATCH OF WHAT APPEARED TO BE DRY SNOW LAYING ACROSS THE RWY. IT WAS ABOUT 100-150' LONG AND I NOTICED A SLIGHT AMOUNT OF DRAG AS WE WENT THROUGH THE PATCH. JUST PRIOR TO ROTATION WE WENT THROUGH ANOTHER SIMILAR PATCH. AS WE WERE LIFTING OFF I NOTICED WHAT WAS PROBABLY A SIMILAR PATCH OF SNOW (SLUSH) ON THE LAST 1000' OF THE RWY AND I REMEMBER THINKING I WAS GLAD I DIDN'T HAVE TO ABORT IN THAT SITUATION. AFTER SWITCHING TO DEP I ASKED THEM TO PASS ALONG A MESSAGE TO TWR ABOUT THE RWY CONDITION. THEY TOLD ME THEY WERE TOO BUSY, AND TO SWITCH BACK AND GIVE THEM THE MESSAGE MYSELF. I TRIED, BUT THERE WAS CONSTANT COM ON THE FREQ SO I WENT BACK TO WORK WITH CTR. REST OF TRIP AND LNDG WERE UNEVENTFUL. ON ARR AT STOCKHOLM THE OUT-GOING CREW DISCOVERED DAMAGE TO THE BRAKE HEATSHIELDS AND AN ANTI-SKID CABLE. AS A RESULT ALL FOUR REAR WHEELS ON THE ACFT HAD TO BE CHANGED. THEY ALSO COULDN'T GET THE CARGO DOOR OPEN W/O APPLYING HEAT TO MELT THE FROZEN SLUSH IN THE DOOR TRACKS. I THINK THE APPEARANCE OF PATCHES OF SNOW WAS DECEPTIVE. IT IS POSSIBLE THE PATCHES HAD BEEN TREATED WITH SOMETHING CAUSING THEM TO PARTIALLY MELT AND REFREEZE THUS MAKING THEM PARTICULARLY BAD. I DON'T SEE WHERE JUST A PATCH OF PACKED SNOW IS THAT BIG A PROB ON AN OTHERWISE DRY RWY. DURING THE TKOF ROLL I WAS ESPECIALLY ALERT TO ANY INDICATIONS OF ICE OR SNOW INGESTION IN THE ENGS THINKING I WOULD IMMEDIATELY ABORT IF THERE WERE ANY SUCH INDICATIONS, HOWEVER HAVING NONE I CONTINUED THE TKOF. IN RETROSPECT I THINK I SHOULD HAVE ABORTED AT THE FIRST SIGN OF THE PATCHES BEING OTHER THAN JUST PACKED SNOW. ALL THIS IN SPITE OF THE FACT WE WERE ON AN EXCEPTIONALLY LONG RWY. ALSO I THINK WE WERE THE FIRST TO TKOF ON THAT RWY AFTER IT HAD BEEN OPENED. IF THIS WERE TRULY THE CASE IT WOULD HAVE BEEN NICE TO HAVE BEEN SO NOTIFIED BY THE TWR.

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.

Air carrier widebody transport hit patches of snow and slush on takeoff from ord causing damage to a brake heat shield and an antiskid cable. Damage not discovered until postflt inspection at destination.