The Boulton Paul P.124 was a jet trainer designed to replace the Percival Provost, but that didn't enter production.
The Percival Provost was a basic trainer that had replaced the same company's Percival Prentice. At the time the training route went from the Provost to the Boulton Paul P.108 Balliol and then onto operational jet aircraft. In 1951 the Air Ministry decided to change to an all jet training system. A replacement was thus needed for the Provost.
Boulton Paul submitted the P.124 and the P.125. The P.124 had moderately swept wings and horizontal tail, and a sharply swept fin and rudder. The engine intakes were in the wing roots, with the engine carried behind the wings. It was to be powered by an Armstrong Siddeley Viper engine. It was designed to serve as an armament trainer, and was given one fixed forward firing machine gun and the ability to carry a mix of weapons including two 250lb bombs or six 60lb rockets. The aircraft would also have carried a G.45 camera. The crew of two sat side by side on ejector seats, and the cockpit had an all round vision canopy. The P.124 was similar in layout to the earlier Boulton Paul P.119, another rejected design for a jet trainer.
It wasn't accepted for production, and a jet powered version of the Provost was chosen instead. The P.125, which was a jet powered version of the Boulton Paul Balliol piston engined trainer was also rejected.
Engine: Armstrong Siddeley Viper ASV.5
Power: 1,640lb static thrust
Maximum take-off weight:
Max speed: 302kt at 30,000ft; 330kt at 30,000ft
Cruising speed: 278kt at 30,000ft
Service ceiling: 41,000ft
Armament: One 0.5in machine gun in wing
Bomb load: Two 250lb bombs, six 60lb rockets, two 100 gallon drop tanks or eight practice bombs