The Explorator in my group has always been "combat averse" ("cowardly" is such an ugly word...) and although on paper he's one of the more capable combatants in the party the player has always chosen, fairly, to play the PC as reluctant to get involved in any conflict. After all people get hurt, possibly even killed, gear could be damaged and data lost - unthinkable!
Previously this has lead to trying to ignore fights going on around him while he got on with repairing a machine all the way to running off when he and the RT were jumped in an alley, resulting in the RT being abducted by Death Cultists.
I would stress that I have NO PROBLEM with this - it's the way the player always envisaged the character; he's a scholar not a combatant, it's a very suitable "type" for a tech priest and it flies in the face of the combat focused "mini-tank" tech priest that I had in my previous Dark Heresy campaign.
However he's now cottoned on to the idea that with ready access to his personal servo skull and servitor (and possibly a suitable mobile Cogitator (i.e. as the Acolytes use in the novel "Scourge the Heretic")) he doesn't *need* to accompany the other Explorers, preferring to remain on board ship or in whatever local residence they have set up and leaving the "grunts" to do all the heavy lifting while he works on his own projects or offers "remote support".
Again, that all seems fitting to the character and could be quite interesting - however has anyone got any ideas how I can keep this fair - i.e ensure that there's the same amount of risk for him as other players and possible ways to ensure that he can equally contribute to missions without compromising what seems like an interesting and memorable concept?