How Old is This New Tire?
by Adrian A. Eichhorn
Reprinted with permission from FAA
Aviation News
A
new tire on my Bonanza was purchased via mail order in August 2004 from a
reputable source that was listed in a major aviation trade publication. After
checking to determine just how 'new' my new tire really was, I discovered that
it was already eight years old!
HOW TO DETERMINE A TIRE'S
AGE
Look for a molded-in-plate on the side of the tire.
In the plate will be a series of numbers and perhaps some letters.
Goodyear (Flight Custom
III, Flight Special II, Flight Eagle, and Flight Leader)
Aircraft tires
manufactured by Goodyear are clearly marked with an eight-character serial
number code that represents the year, Julian date of production, and tire ID
number. Character one represents the year; character two, three, and four
indicates the day; characters five, six, seven, and eight signify the individual
tire ID number. For more information see
http://www.goodyearaviation.com. (FYI: The Julian calendar dates are simply
a continuous count of days. For example: January 1 is expressed as 001; December
31 is expressed as 365.)
McCreary (Superhawk,
Airhawk and Airtrack)
McCreary tires
are marked with an eleven-digit code. The first four digits identify the
McCreary plant number; the next four digits identify the Mc-Creary mold Number
(Part No.); the next two digits identify the week of the year and the last digit
indicates the year of manufacture. For example: CY8A-B3H6020 (CY8A) is the plant
number; (B3H6) is the mold or part number; (02) is the 2nd week of the year and
(0) for 1990.
Michelin (Air, Aviator and
Condor)
Michelin
aircraft tires are marked with a ten-digit serial number that also represents
the year and Julian date that the tire was produced. Character one represents
the last number of the manufacturing year; the next three numbers indicate the
Julian day and the remaining six characters are related to decade of production,
manufacturing facility and production number. For example: 9211P0025 (9) is for
1999, (211) is the Julian day - 29 July, (P) pertains to the facility and
decade, 0025 is a unique production number. For more information see https://aircraft.michelin.com.
Retread Tires
Retread tires
have the original manufacturers date and
they are also marked with month and year of retread.
But how do you know if the
tire was made in 1999 of 1989? Some tire manufacturers also molded a little
triangle into the tire adjacent to the plate with one of the points facing to
the left or right. The direction of the triangle gave the decade of the
manufacture. Since not every manufacture did this, it is easiest to take a close
look at the tire and make an educated guess as to decade of manufacture by the
condition of the rubber (e.g. does it look dry and crazed with lots of tiny
cracks?) Of course, if the aircraft was made in 1970 and it still has the
original tires on it, then the dating is already done for you.
Adrian A. Eichhorn is a
7,000-hour pilot for the Federal Aviation Administration. He is based at Ronald
Reagan Washington National Airport. He is also a volunteer Aviation Safety
Counselor for the Washington Flight Standards District Office and the 2001
National Safety Counselor of The Year. He holds an Airframe & Powerplant
certificate with Inspection Authorization (IA).
|