W81592 - Incident: Cargojet B763 at Sao Paulo on Nov 7th 2021

A Cargojet Airways Boeing 767-300 freighter, registration C-GVIJ performing flight W8-1592 from Sao Paulo Viracopos,SP (Brazil) to Miami,FL (USA) with 2 crew, was climbing out of Viracopos Airport when the crew stopped the climb at FL260 due to cabin altitude caution, the crew worked the related checklists but were unable to maintain cabin pressure in any mode. The crew declared PAN PAN and descended to FL100, during the descent the cabin altitude alert activated. The aircraft levelled off at FL100, burned off fuel and returned to Viracopos for a safe landing on runway 15 about 2.5 hours after departure.