The preliminary report for the LNI610 crash shows how much distractive conversation there was between ATC and LIN610 at a time when the pilots clearly didn't have the aircraft under control – as evidenced by the FDR data – and should have talked to each other to diagnose the problem, rather than to ATC. This violates the principle "aviate - navigate - communicate".
While it clearly falls within the responsibility of the crew to declare an emergency, my question is posed from the point of view of air traffic control:
(from the preliminary report, p.1+2)
At 23:21:53 UTC, the LNI610 SIC requested approval to the TE controller “to some holding point”. The TE controller asked the LNI610 the problem of the aircraft and the pilot responded “flight control problem”.
At 23:24:51 UTC, the TE controller added “FLIGHT CONT TROB” text for LNI610 target label on the controller radar system as reminder that the flight was experiencing flight control problem.
The preliminary report reveals how much dispensable talk there was between ATC and LNI610 in this crucial moments even after the flight was marked as experiencing flight control problems.
My question is:
Seeing that the flight was marked by ATC as "FLIGHT CONT TROB", could ATC have handled the situation differently, e.g. bothering them less or even handling the situation outright as PAN PAN (don't restrict navigation, reroute other traffic, avoid communication as much as possible) even though it was not declared as such by the crew ?
Or did they essentially have their hands tied, obliged to treat the flight as any other as long as no emergency is officially declared via either MAYDAY or PAN PAN ?
I very much welcome any answers, including from pilots or ATC controllers who are unfamiliar with this particular accident, but can share their work experience (how this is handled in practice) AND/OR point to specific rules (how this should be handled in theory).
FDR data (timestamps + pink vertical lines added by myself at 23:21:53 and 23:24:51 UTC corresponding to the ATC excerpts quoted above):