How I'd implement playable escorts, were I coding God! :
1. Make a playable "Convoy Commander" (CC) who is based on an escort destroyer or sloop.
2. The CC has the ability to:
- send any escort(s) to either a point in relation to the moving convoy
to a contact held by another escort
to an area to maintain an asdic search relative to the moving convoy(for an interval of 5 mins to 3 hours)
to an area in relation to the moving convoy (as above)
to detach an escort to occupy the nearest opening in the screen
to cease an asdic search and reposition to nearest open escort slot
to come to all stop and listen with hydrophones
to relocate to another escorts position, on reaching, the replaced escort may be directed to a new location, otherwise it moves to nearest one
Otherwise all escort actions are AI, until playable escorts come into game, thence:
Some 6(?) or so players would be able to play as escorts. They may not enter a u-boat and then join the allies in that lobby. Players may relocate to an AI destroyer or Corvette that acquires an ASDIC contact, or detects a u-boat on the surface. Once the last player leaves that escort, the escort then returns to the direct command of the CC. So, most of the boring patrol side of things is done by the AI as of routine, but any escort may be temporarily manned at any time, by players. When so manned, all AI detection modes are suppressed, meaning visual contact is by human sight, not "detection range", and asdic contact is by human manual use of the Asdic, rather than AI "use" of it. 2 players would be the minimum crew - skipper/helmsman and asdic operator. Optionally more could join as gunners/dc operators. The skipper decides on the DC depth and either sets them, or orders the player to do so if present. Boats operated by human players would shew with a distinct marking on the CC's map. The CC may direct players to a particular escort. Roles not occupied by human players would prosecute AI behaviour for that role.
The aim being to minimise the number of allied players required to mount an intelligent defence of the convoy, without recourse to highly predicatable AI behaviours, but instead to have (if a CC is in post) the AI carry the burden of the boring aspects of the patrol, but have human players tending to prosecute attacks, or to otherwise keep a u-boat at depth via asdic searches. The lethality of DC attacks could be dialled back, as more DC attacks would tend to occur one a uboat is detected. This would create the highly personal and dramatic contest of the u-boat captain trying to outwit the escort and vice versa.