“Escorts are vessels intended to protect and assist larger vessels. They are capable of independent action, but are usually assigned to support battleships and cruisers.” (Fighting Ships of the Shattered Imperium, GDW, 1990, p. 66)
“Escorts keep smaller enemy vessels away from high-value units, preventing the enemy from conducting effective reconnaissance or launching a strike with one-shot weapons….Fleet escorts such as the PF Sloan class are intended to accompany heavier ships and to intercept light craft and missiles headed for the high-value units…close escorts shelter under the big guns of a larger ship and in turn protects it from attack by light craft…being quite capable of destroying incoming fighters or gunships.” (Sector Fleet, Avenger Enterprises 2010, pp. 24-25).
Canonical material from Traveller defines a role for escorts, but the Classic Traveller High Guard combat system does not recognize or enable their use in a similar manner. The Battle Formation Step establishes two lines (Line of Battle and Reserve) and in the Combat Step, the ships are placed in order from largest to smallest and presented to combat in that order. The rules specify that “each battery on a ship may fire once in the turn, either offensively against another ship, or defensively against incoming fire (High Guard p. 40). My usual interpretation has been that each ship fires defensively against incoming fire only aimed against it. The result here is that smaller ships get lost in the larger battle.
I am experimenting with assigning screens for ships. In the Battle Formation Step, as each ship is placed in either the Line or Reserve, up to two other ships are declared as “escorts” for the ship by being placed underneath/behind the screened ship. In the Combat Step, when the screened ship is presented as a target the screened ships are presented at the same time. The attacker has a choice of attacking the screened ship OR an escort. If attacking the escort, all attacking USP is reduced by 1 (“sheltered by the larger ship”), but the “effective agility” of the escort is reduced by 1 also (“tied on”). If attacking the screened ship, the escorts can contribute defenses with a USP reduction of 1 (systems not optimized for defense of something other than itself). When the screened ship is the attacker, the escorts can also attack, but with a USP reduced by 2 (restricted in ability to maneuver).