Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe
Flight Crew Diverted; Flight Crew Landed As Precaution; Flight Crew Landed in Emergency Condition; General Declared Emergency
Aircraft
During climb out passing FL200 received ECAM warning HIGH BRAKE TEMP; Pulled up wheel page and saw #5 [brake] temp was 325C and rising. Immediately executed high speed descent with ATC approval to FL190; slowed below 250KIAS; and extended landing gear.  Temp dropped to below 100C.  Diverted and declared emergency. Turned brake fans on after landing during rollout; temp was stable on all wheels below 100. After fire crews and maintenance cleared us to taxi to parking received ECAM warning again and #5 temp went to 29 C; turned on brake fans again and temp slowly dropped. Appeared to be brake malfunction on wheel #5.
During climb to cruising altitude while passing FL190; we got a Master Caution and ECAM warning for Brake Overtemp. We referred to the Wheels page and noted the temp on Number 5 indicator was at 320 degrees and rising. The aircraft had an MEL for Brake Indicator so we pulled the MEL and it was for Number 8. We coordinated with Center to descend to FL190 and slow to drop the gear. We initiated a high speed descent and slowed to 250 and dropped the gear. Temp began to slowly decrease. We coordinated a divert and declared an emergency. All checklists were complied with. Diverted and flew the ILS [approach]. Turned brake fans on after landing (during rollout) and noted temp was not much over 100 degrees. Turned fans off after fire crew and MX cleared us to taxi to parking. We noted temperature increasing and got another ECAM warning at 295 degrees. Brake fans were turned back on and we parked the aircraft at ramp. Shutdown was normal.Brake system malfunction caused overtemp of brakes after retraction and in flight.
A300-600 flight crew reported brake over temp after takeoff. They declared an emergency and diverted to nearest suitable airport.