It might be interesting to compare the entries for M.148 and TS-149:
A.W.168 – 47ft 6in x 59ft 9in; 555sq ft; 40,000lb; 2x 7,000lbf PS.43 Gyron Junior; 674mph SL; 510nm radius full load; Red B/Green C/4,000lb, 24x rockets; jet deflection & blown flaps
B.103 – 42ft 6in x 61ft 6in; 535sq ft; 39,308lb (46,000lb overload); 2x 7,000lbf PS.43 Gyron Junior; 737mph SL; 800nm radius (1,115nm at overload); Red B/Green C/4,000lb, 24x rockets; blown flaps [with 11,400lbf BE.33 M1.05, 15% more range]
Fairey M.148 – 42 x 51ft; 500sq ft; 39,500lb; 2x 7,000lbf PS.43 Gyron Junior; 658mph SL; 1,660 miles (2,130 miles at overload); Red B/Green C/4,000lb, 24x rockets; blown flaps
Hawker P.1108 – 40 x 58ft; 510sq ft; ?x weight; 4x RB.115; ??? speed and range; Red B/Green C/4,000lb, 24x rockets; no special STOL features
Short PD.13 – 38ft 1in x 51ft; 482sq ft; 40,520lb; 2x 12,500lbf Avon RA.19; 758mph SL; ??? range (met spec); Red B/Green C/4,000lb, 24x rockets; jet deflection
Westland M.148 – 43 x 50ft 10in; 863sq ft; 40,915lb; 2x 6,830lbf PS.42 Gyron Junior; 674mph SL; ??? range (met spec); Red B/Green C/4,000lb (8,000lb overload), 24x rockets; jet deflection
Saro P.178 (not tendered) – 37ft 6in x 48ft 9in; 470sq ft; 40,000lb; 2x PS.37 Gyron Junior; ??? speed and range; Red B/4,000lb; no special STOL features
Bell D-2001 – 34ft 10in x 49ft 5in; 200sq ft; 32,384lb; 4x 3,660lbf J85-GE-5 & 4x 2,450lbf J85-GE-1 lift units; 697mph SL (23,000lb); 300-856nm radius; 1x Mk.28/Corvus & 2,000lb; VTOL
Boeing Model 806 – 37ft 11in x 54ft 11in; 400sq ft; 37,086lb (40,411lb max); 1x 12,200-18,600lb J79-GE-X207A; 722mph SL; ??? range (met spec); 1x nuke/5,000lb; no special STOL features
Boeing Model 807 – 41ft 7.5in x 52ft 10in; 290sq ft; 30,728lb (32,768lb overload); 2x 4,050shp T56; 599mph SL; 1,250nm radius (external fuel); 1x nuke/hardpoints total 12,000lb; BLC
Chance-Vought V-416 – 36ft 2.5in x 49ft 10in; 330sq ft; 37,260lb; 2x 9,800lbf J52; 697mph SL; 1,000nm radius; hardpoints total 14,800lb; thrust deflection
Douglas D-715 – 46 x 54ft; 450.7sq ft; 48,660lb; 2x 9,800lbf J52; 656mph SL; 1??? range (met spec); 9,575lb; optional blown flaps
Douglas D-725 (mod A4D-3) – 27ft 6in x 43ft 5in; 272sq ft; 22,599lb; 1x 8,500-9,800lb J52; 654mph SL; ??? range (met spec); hardpoint total 9,155lb; no special STOL features
Grumman G-128 – 51 x 53ft 2.5in; 520sq ft; 42,265lb (52,000lb max); 2x 8,500lb J52; 663mph SL; 1,370nm radius; hardpoint total 18,000lb; thrust deflection
Lockheed CL-364-2 – 46 x 45ft 9in; 340sq ft; 33,275lb; 1x 9,800lb J52; 638mph SL; ??? range (met spec); hardpoint total 12,575lb; no special STOL features
Martin Model 345 – 55 x 55ft; 550sq ft; 48,537lb; 2x 8,500lbf J52; 618mph SL; ??? range (met spec)5x hardpoints; no special STOL features
Martin Model 346 – 43 x 41ft 8in; 365sq ft; 31,821lb; 1x reheated J52; 512kt; ??? range (met spec)1x Mk28/5,000lb; no special STOL features
NA ‘Vigilante’: ??? size; ??? weight; 1x reheated J52; ??? speed and range; 5x hardpoints; no special STOL features
Caveats:
- for the TS-149 entries I've omitted the weights for the 300nm sortie
- for the TS-149 entries the hardpoint total is given but max loads may not have been carried on every hardpoint
- for the M.148T entries the weaponry is that listed for the spec, some of the entries also had additional external bombs
Immediate take away facts:
- the US aircraft were slightly lighter and had more thrust but often lacked special STOL features though several of the entries had them
- internal carriage was essential to M.148T and probably pushed up size and weight
- the US aircraft had wider provision of guided missiles including Sidewinder in some design from the outset
- only two engines; Gyron Junior and J52 were really in contention for these designs