As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED. ON CLIMB OUT FLIGHT CREW WAS UNABLE TO COOL DOWN THE AIRCRAFT. AN EMERGENCY WAS DECLARED AND THE AIRCRAFT RETURNED TO DFW FOR AN UNSCHEDULED LANDING. THE AC WAS NOT OVERWEIGHT AND LANDED WITHOUT INCIDENT. REPLACE THE RT SECONDARY HEAT EXCHANGER PER AMM 21-51-04 AND 21-51-05. SEE ALSO SDR'S AALA20180729002 & AALA201807309050.