The tragedy is the second to strike the Sidecar event this week after Frenchman Cesar Chanal lost his life at the same part of the course last weekend on the opening day of racing. His passenger, Olivier Lavorel, remains in a Liverpool hospital in a critical condition.
A statement from the Isle of Man TT Races read: "With a deep sense of sorrow, the Isle of Man TT Races can confirm that Roger Stockton, 56, and Bradley Stockton, 21, from Crewe, Cheshire were both killed in an incident on the second and final lap of the second Sidecar Race of the 2022 Isle of Man TT Races. The incident occurred at Ago's Leap, just under one mile into the lap.
"Roger and Bradley were father and son, and driver and passenger respectively.
"Roger was an experienced TT competitor, with today's race marking his 20th TT race start. He competed at the TT regularly from 2000 to 2008, before then returning in 2010, 2017 and at this year's event. In his career, he claimed a total of twelve top-20 finishes and four top-10 finishes, as well as 10 Bronze Replicas.
"Bradley was a newcomer to the TT and finished his first TT race on Monday, securing an impressive 8th-place finish alongside his father. 2022 was their fifth season racing together, and Roger and Bradley were regular podium finishers and frontrunners in the British F2 Sidecar Cup Championship, finishing second in the championship in 2021.
"The Isle of Man TT Races pass on their deepest sympathy to Roger and Bradley's families, loved ones, and friends."
The tragedy is the latest in what has been a harrowing return to the TT after two cancelled years in 2020 and 2021 due to Covid-19. Welshman Mark Purslow was killed in a crash during practice last week, and veteran Northern Irishman Davy Russell died following an incident in Tuesday's first Supersport race.
Saturday was due to be the final day of the two-week festival when the blue-riband Senior TT - as well as the delayed second Supersport race that had already been rained off on Thursday and Friday - were scheduled to take place either side of the second Sidecar event.
But although both the Supersport and Sidecar races were able to get under way, deteriorating weather conditions meant that the main event of the week had to be postponed until Sunday.