Narrative:

The takeoff was conducted on a runway that had some wet snow and or slush. The weight of the aircraft required that an improved climb takeoff be performed. After takeoff I checked the performance book to see if it was legal to do an improved climb takeoff from a contaminated runway. It is not permitted. I then checked the runway condition on the weight and balance. The runway was shown to be wet, not contaminated. At that time I felt that the takeoff was not legal. Now I do not know if it was legal or not because I do not have a good definition of contamination for a runway. Performance engineering at the airline told me that boeing does not take a penalty for less than 1/8 inches of water snow or slush on a runway. Our books do not reference a minimum limit for contamination. Takeoff data for contamination is not approved data. The company often uses the tower/ATIS report for runway condition but we do not know what criteria the FAA uses for runway condition. It is impossible for the flight crew to know the depth of contamination on a runway. The entire scope at operations off of runways that are not clean and dry is a grey area in the regulations. On that day I think we might have been legal but I am sure we could not have stopped on the runway if we had rejected close to V1. Supplemental information from acn 294398: after de-icing and checking for 'clear wings' we ran appropriate checklists and takeoff on runway 28R. Conditions at the time were 1 1/2 mi visibility 30 degrees and light snow falling. Company provided weight and balance data showed a 'flaps 5, improved climb' on a wet runway, maximum gross allowable weight 135000 pounds. We were about 132000 pounds for takeoff. We were so concerned with making sure wings were 'clear' we overlooked fact that, at 30 degrees, the runway was wet, it was contaminated with wet snow and we should have used 'contaminated runway analysis data' which would have resulted in a maximum allowable gross weight of about 107500 pounds roughly. Lesson we learned; you can't trust the 'company' to provide correct weight and balance data. You must evaluate their decisions for appropriateness. They want you to takeoff for their revenue whether it's safe is up to us as the pilots!

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Original NASA ASRS Text

Title: TKOF PROC ON CONTAMINATED SNOW COVERED RWY QUESTIONED BY FLC AFTER THE EVENT.

Narrative: THE TKOF WAS CONDUCTED ON A RWY THAT HAD SOME WET SNOW AND OR SLUSH. THE WT OF THE ACFT REQUIRED THAT AN IMPROVED CLB TKOF BE PERFORMED. AFTER TKOF I CHKED THE PERFORMANCE BOOK TO SEE IF IT WAS LEGAL TO DO AN IMPROVED CLB TKOF FROM A CONTAMINATED RWY. IT IS NOT PERMITTED. I THEN CHKED THE RWY CONDITION ON THE WT AND BAL. THE RWY WAS SHOWN TO BE WET, NOT CONTAMINATED. AT THAT TIME I FELT THAT THE TKOF WAS NOT LEGAL. NOW I DO NOT KNOW IF IT WAS LEGAL OR NOT BECAUSE I DO NOT HAVE A GOOD DEFINITION OF CONTAMINATION FOR A RWY. PERFORMANCE ENGINEERING AT THE AIRLINE TOLD ME THAT BOEING DOES NOT TAKE A PENALTY FOR LESS THAN 1/8 INCHES OF WATER SNOW OR SLUSH ON A RWY. OUR BOOKS DO NOT REF A MINIMUM LIMIT FOR CONTAMINATION. TKOF DATA FOR CONTAMINATION IS NOT APPROVED DATA. THE COMPANY OFTEN USES THE TOWER/ATIS RPT FOR RWY CONDITION BUT WE DO NOT KNOW WHAT CRITERIA THE FAA USES FOR RWY CONDITION. IT IS IMPOSSIBLE FOR THE FLC TO KNOW THE DEPTH OF CONTAMINATION ON A RWY. THE ENTIRE SCOPE AT OPS OFF OF RWYS THAT ARE NOT CLEAN AND DRY IS A GREY AREA IN THE REGULATIONS. ON THAT DAY I THINK WE MIGHT HAVE BEEN LEGAL BUT I AM SURE WE COULD NOT HAVE STOPPED ON THE RWY IF WE HAD REJECTED CLOSE TO V1. SUPPLEMENTAL INFO FROM ACN 294398: AFTER DE-ICING AND CHKING FOR 'CLR WINGS' WE RAN APPROPRIATE CHKLISTS AND TKOF ON RWY 28R. CONDITIONS AT THE TIME WERE 1 1/2 MI VISIBILITY 30 DEGS AND LIGHT SNOW FALLING. COMPANY PROVIDED WT AND BAL DATA SHOWED A 'FLAPS 5, IMPROVED CLB' ON A WET RWY, MAX GROSS ALLOWABLE WT 135000 LBS. WE WERE ABOUT 132000 LBS FOR TKOF. WE WERE SO CONCERNED WITH MAKING SURE WINGS WERE 'CLR' WE OVERLOOKED FACT THAT, AT 30 DEGS, THE RWY WAS WET, IT WAS CONTAMINATED WITH WET SNOW AND WE SHOULD HAVE USED 'CONTAMINATED RWY ANALYSIS DATA' WHICH WOULD HAVE RESULTED IN A MAX ALLOWABLE GROSS WT OF ABOUT 107500 LBS ROUGHLY. LESSON WE LEARNED; YOU CAN'T TRUST THE 'COMPANY' TO PROVIDE CORRECT WT AND BAL DATA. YOU MUST EVALUATE THEIR DECISIONS FOR APPROPRIATENESS. THEY WANT YOU TO TKOF FOR THEIR REVENUE WHETHER IT'S SAFE IS UP TO US AS THE PLTS!

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.