As long as it doesn't end up in a flatspin an airliner should be able to pull up from a dive. For an extreme example where this was tested in practice, in the https://en.m.wikipedia.org/wiki/China_Airlines_Flight_006 incident, a pilot lost control of a 747 & ended up diving 30k feet at speeds approaching/potentially exceeding mach 1, then pulled 5 Gs leveling off at 10k feet once he regained situational awareness, & they were still able to land safely, although there was some damage
IMO the bigger problem would be needing multiple helicopters pulling together - wind or the jet's engines might pull the helicopters enough that they'd crash into each other, & you'd definitely want to start the engines before freefall..
IMO the bigger problem would be needing multiple helicopters pulling together - wind or the jet's engines might pull the helicopters enough that they'd crash into each other, & you'd definitely want to start the engines before freefall..