The LCT(R) Mk 3 could carry over a thousand rockets, which were released in 24 salvoes. Anyone in the target area (measuring some 685 m by 145 m/750 by 160 yards) would be unlikely to feel happy as 17 tons of explosive burst around him!
The LCG(L)Mk4 usually had its turrets manned by Royal Marines, and proved most successful. It was more elaborate than its Mk3 predecessor, with more 20-mm mountings, a modified bow form and the after 4.7-in (119-mm) gun made super-firing.
Support firepower during landings was anticipated as being in short supply so, profiting from the successful LCF conversions, 23 LCT(3)s were fitted with two single 119-mm (4.7-in) guns and recategonzed Landing Craft, Gun (Large) or LCG(L). They had ex-destroyer mountings, the latter ships having been rearmed for antisubmarine work. The guns were sited at the same level on a new upper deck with deep bulwarks, and the after weapon had only limited arcs on the beam. Range-finding was rudimentary but the craft needed to operate at some distance from the beach, firstly to gain some falling trajectory for their guns and secondly to stay out of range of enemy weapons (particularly mortars) as their ammunition stowage was considered vulnerable.
They served well in Europe, so 10 LCT(4)s were also converted. These craft were flimsier but had extra beam, making for a steadier platform. They had a simple director, with their larger guns mounted superimposed and with full blast shielding. Light armouring was also added. Unfortunately only one was completed in time for the Far Eastern war.
The Landing Craft, Gun (Medium) or LCG(M) was designed to go right in and was protected for the purpose, while carrying two army 25- or 17-pdr guns in single armoured turrets. They were considered proof against medium-calibre return fire (in fact, they were not) and were meant to engage targets on the run in, and then to flood down to reduce freeboard as far as possible and, by sitting on the bottom, shoot accurately while gaining extra protection from their submergence. Their hulls were one-offs, with a ship bow and a low initial freeboard. Their metacentric heights gave them legendary roll angles and they manoeuvred poorly.
A most spectacular modification to LCTs was to the Landing Craft, Tank (Rocket) or LCT(R). Both LCT(2)s and LCT(3)s were used, the whole forward end looking like a vast milk crate for the launch of 792 or 1,064 127-mm (5-m) rockets, Fixed in elevation and bearing, the weapons were launched from precisely 2-mile (3.2-km) range in 24 salvoes. Ideally the bombs came down at 10-yard intervals, laying a carpet of about 17 tons of explosive over an area of 685 by 145 m (750 by 160 yards) of the enemy defences. One set of reloads was carried and, this fired, the craft disposed of her launchers and did duty as a ferry.
Displacement: 495 tons full load
Dimensions: length 58.5 m (192 ft); beam 9.4 m (31 ft); draught 1.1/1.8 m (3.5/6 ft)
Propulsion: two diesels delivering 746 k W (1,000 bhp) to two shafts
Performance: maximum speed 10 kts; range 2688 km ( 1,670 miles) at 8.5 kts
Armament: two single 119-mm (4.7-in) and one or two twin 20-mm AA guns