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Volume 1, Issue 3  RETREAD/ECONOMIC OPTIMIZATION AT BRAZILIAN AIRLINES
In Brazil, airlines like VARIG, TAM, GOL and VASP are excellent examples of tire retread utilization. Working closely with Goodyear they have developed a good program of training on aircraft tire care and preventive maintenance with safety as the first priority and cost reduction as an ongoing economic goal. VARIG and TAM Airlines, for instance, operating a fleet of nearly 200 aircraft that include Boeing, Airbus, Fokker, and Embraer jets are quite satisfied with the results of their Goodyear retread programs. These programs yield an average of six retread levels and, in some particular cases, as many as ten to eleven retread levels. In the case of TAM Airlines, specifically considering their fleet of forty-four A319/320 aircraft, their tires are achieving a 95% acceptance level for retreading in all retread levels up to R-9 and reaching 86.8% for R-10. This results from combining a good product with a complete tire care and maintenance program to insure safety and reduced cost. With this combination, these Brazilian airlines have the highest retread and lowest cost per landing levels in the world.
A tire wear evaluation was conducted between February and November 2003 at the University of North Dakota, Grand Forks, where fifty eight (58) main landing gear tires were evaluated for wear characteristics on 29 of UND’s Piper Warrior and Arrow aircraft. Tires evaluated included, Goodyear Flight Custom III, Goodyear Flight Special II and Michelin Air. At approximately every 60 hours of flight time, the tires were checked for remaining tread depth at 3 points in each grove, tire pressure, and the number of landings. Results showed that Goodyear Flight Custom III provided an average of 1386 landings compared to Michelin Air which averaged 953, or 45% more landings on Goodyear Flight Custom III. Goodyear’s less expensive Flight Special tire is comparable in performance to the Michelin Air.
 
Changes in the Tilburg plant are huge. The distance a tire now travels in plant has been reduced by a factor of three. Goodyear has also identified the “ideal” number of tires to be processing at any one time. By reducing floor-space used and having every job physically in view to every operator, Goodyear Tilburg has created a better sense of teamwork which was often missing before. Goodyear associates see that over-production as well as under-production has a negative impact and causes waste. Another effect of reduced floor space is the move from a “push” to “pull” production. Instead of having many tires to choose from, the operator has to “pull” the tires from the previous step thereby creating the expectation that there will always be a tire there when he needs one. By having fewer tires in production and verified immediately after receipt, Goodyear Tilburg has much more flexibility to respond to ever increasing customer demands.
Due to the unique landing characteristics of the B747-400, the last row of the body gear, in particular wheel positions #7, 8, 11, and 12 are subject to the most severe operating condition — the last to leave and the first to touch the tarmac. Likewise, tires installed in these four positions experience faster wear and, therefore, require relatively more frequent tire change. According to our experience with B747-400, the difference in landing cycle achieved at different airlines worldwide are predominantly due to the proportion between the fleet’s passenger and freighter mix, and tire pressure checks. Airlines performing daily tire pressure checks experience higher average landing performance resulting in lower airlines operational cost than those airlines that do not perform daily tire pressure checks. 
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The aircraft retreading practice was
adopted in the aviation industry in the
1930’s. Although started initially in the
United States by Goodyear, it was introduced
in Latin America in the 1960’s by
Goodyear to support airlines in Brazil.
Retreading is primarily used with large
aircraft sizes where the tire body or casing
makes up a significant material cost.
As airlines are extremely cost conscience,
reusing a significant material
investment is a competitive advantage.
Approximately 85% of an airline tire inventory
or pool is composed of retreaded
tires. Fifteen percent of the airline pool is
composed of new tires which are injected into the pool as the casings are being retired due to a
variety of reasons that can include cuts, weather checking, contamination, fatigue, retread limit,
etc. The average cost of an airline retreaded tire is approximately 30% of cost of a new tire. This
means that by achieving only two retreads (R-2), it is possible to reduce by 50% the tire operational
cost of an airline. All this with the same quality and safety.
Recent changes in Goodyear Tilburg’s retread tire plant layout and the completion of the investment
program has not only brought a more logical plant set-up but has also brought a new way of thinking
and greater flexibility. This new way of thinking is lean manufacturing and it’s a very simple principle.
To be lean one must broaden one’s view of what waste is. Waste is not only scrap tires and re-runs.
Waste is everything an organization does that does not add value to the product. This new way of
thinking can be adapted to all places, especially the administrative office where waste is not often as
easily identifiable as in the plant.
The Boeing 747 was born out of the explosion of
air travel popularity in the 1960s, and it remains
still today the largest commercial aircraft in commercial
operation. Over the years, Goodyear
Aviation has been collecting and analyzing landing
cycles on B747-400 tires operated by our
customers worldwide. It is interesting to see that
landing cycles vary from one airline to the other
with the lowest landing cycles on Airline C, and
the highest on Airline A while the average
landing cycle for six airlines, A - F is 190.75.