Just want to add a few facts to the conjecture.....
GBNSO was one of the 5 second hand Fireflies bought by Huntings when they got the initial JEFTS contract. This reduced the average cost of the fleet. It had the T67M 160 hp two bladed prop they all had, but was given a red spinner on Red Nose Day one year and always known as Bonzo.
The T67M200 had the Bulldog engine, 200hp and a three bladed prop. Barkston had two - G HONG and G KONG, no guesses where they came from. They really did not perform much better than the 160s, and frankly the prop/engine match up was not great. Weight and CofG had to be watched for spinning & aeros.
The T67M260 was by far the best example, and I also flew it for 9 years in Bahrain where naturally it had an air conditioner.
The accident at Barkston has been described elsewhere. Mis-handled recovery, late takeover by QFI and jump out at Min Ht. All crews always wore Parachutes!
An extra 1000 feet was added to the calculations for safe recovery and the school had no further problems.
I did not know these unfortunate students. I do not know how much training or time on type they had, but over the years many competent pilots have suffered when not familiar, not in practise, and not following a drill precisely to the letter. RIP
The Jordanians have also had fatal accidents in their Fireflies. One aircraft struck a bus at LL. To my knowledge the machine was not at fault