An ATR42 flight crew at tvc did not understand braking report issued by the tower.

Attributes
ACN	458042
Time
Date	199912
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : tvc.airport
State Reference	MI
Altitude	agl single value : 0
Environment
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	ATR 42
Operating Under FAR Part	Part 121
Flight Phase	ground : parked
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 90 flight time total : 12000 flight time type : 4000
ASRS Report	458042
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : multi engine
Events
Anomaly	other anomaly other
Resolutory Action	none taken : unable
Supplementary
Problem Areas	ATC Human Performance Airport
Primary Problem	ATC Human Performance

Narrative:

Before departing ord for tvc, our field report for tvc showed braking action for runway 28 as '118 104 86 mu.' in checking our flight manual, we could find no chart (mu, saab, tapley, etc) that would correspond to numbers over 100. We called our company dispatch and they also could not find a chart that related to '118 104 86' numbers. The dispatcher called the tvc tower and asked them for a braking action report, which was obtained from another aircraft, and passed on to us before we departed ord for tvc. Arriving in the tvc area, we asked the tvc tower for a braking action update, and they gave us numbers of '108, 104, 86' again. We asked them what those numbers corresponded to (ie, good/fair/poor/nil braking) and they said they did not know as the airport authority/authorized at tvc only gave them numbers but no conversion chart. This seems like a very dangerous situation by tvc as they have a braking condition data system that flcs, airline dispatchers and even ATC cannot relate to. Tvc has some very nasty winter WX (very close to lake michigan with lots of lake effect snow) so braking action data is very much needed.

Original NASA ASRS Text

Title: AN ATR42 FLC AT TVC DID NOT UNDERSTAND BRAKING RPT ISSUED BY THE TWR.

Narrative: BEFORE DEPARTING ORD FOR TVC, OUR FIELD RPT FOR TVC SHOWED BRAKING ACTION FOR RWY 28 AS '118 104 86 MU.' IN CHKING OUR FLT MANUAL, WE COULD FIND NO CHART (MU, SAAB, TAPLEY, ETC) THAT WOULD CORRESPOND TO NUMBERS OVER 100. WE CALLED OUR COMPANY DISPATCH AND THEY ALSO COULD NOT FIND A CHART THAT RELATED TO '118 104 86' NUMBERS. THE DISPATCHER CALLED THE TVC TWR AND ASKED THEM FOR A BRAKING ACTION RPT, WHICH WAS OBTAINED FROM ANOTHER ACFT, AND PASSED ON TO US BEFORE WE DEPARTED ORD FOR TVC. ARRIVING IN THE TVC AREA, WE ASKED THE TVC TWR FOR A BRAKING ACTION UPDATE, AND THEY GAVE US NUMBERS OF '108, 104, 86' AGAIN. WE ASKED THEM WHAT THOSE NUMBERS CORRESPONDED TO (IE, GOOD/FAIR/POOR/NIL BRAKING) AND THEY SAID THEY DID NOT KNOW AS THE ARPT AUTH AT TVC ONLY GAVE THEM NUMBERS BUT NO CONVERSION CHART. THIS SEEMS LIKE A VERY DANGEROUS SIT BY TVC AS THEY HAVE A BRAKING CONDITION DATA SYS THAT FLCS, AIRLINE DISPATCHERS AND EVEN ATC CANNOT RELATE TO. TVC HAS SOME VERY NASTY WINTER WX (VERY CLOSE TO LAKE MICHIGAN WITH LOTS OF LAKE EFFECT SNOW) SO BRAKING ACTION DATA IS VERY MUCH NEEDED.

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.