Incident: Saudia B772 at Madinah and Karachi on Sep 9th 2017, sauna in flight
A Saudi Arabian Airlines Boeing 777-200, registration HZ-AKV performing flight SV-706 from Madinah (Saudi Arabia) to Karachi (Pakistan) carrying pilgrims returning from the Hajj, departed Madinah with a delay of about 3 hours, climbed to FL370 enroute and landed in Karachi with a delay of about 2.5 hours. No medical assistance was needed in Karachi.
Passengers reported they had boarded the flight already when the flight was delayed for about 3 hours with the air conditioning was not working. Flight attendants claimed the air conditioning would start working right after takeoff, however, the cabin didn't cool down after departure causing a number of passengers to feel unwell (one passenger claimed 6 fellow passengers fainted).
Passenger videos posted on Facebook, see here and here, show passengers and cabin crew ventilating air onto passengers not feeling well using aircraft safety cards.
The occurrence aircraft departed for the return flight SV-709 to Riyadh (Saudi Arabia) after about 3 hours on the ground.
https://avherald.com/h?article=4ae37ab8&opt=0