The temperature reached by the brakes would depend on several factors, posted above.
The indication in the 747 Classic is a vertical scale temperature, one for each gear, and one amber brake overheat light, mounted on the F/E panel. Should the overheat light illuminate, operation of the LF
(left front), RF (right front), LR
(left rear), and RR
(right rear) selector switches will show heat condition of each brake. The meters are color coded to designated temperature range. Green is safe, for temperature between 0 to 300°F; amber is marginal, for temperature between 300 and 700°F; and red is unsafe, for temperature over 700 to 1000°F.
In general, after a normal landing brake indication is at the end of the green range. When temperature is at the beginning of the amber range (10 million foot pounds) would need 25 to 30 minutes ground cooling time or 5 minutes in-flight gear down cooling time.
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