I think Malabo hit the nail on the head........
This departure is completely routine for the Offshore / EMS / Military guys. The CAT A helipad departure profile that needs to be flown in the AW139 does not change whether it's day or night, engine failure or not. The second that aircraft hits TDP and the pilots starts their rotation it's a pure instrument procedure after that. The flying pilot manually flies the profile and acknowledges the non flying pilots callouts while the non flying pilot make his standard calls and monitors for any deviations. If the deviation callout isn't acknowledged and or corrected by the flying pilot, the non flying pilot immediately takes control of the aircraft. This is standard two crew, multi ifr operations anywhere in the world.
I would guess that the departure SOPS's and callouts would look similar to this from 99% of the AW139 Multi Pilot, IFR operators out there
Flying Pilot "Lifting"
Applies collective to pull into hover
Non Flying Pilot "Two AP's"
Ensures both autopilots are on before the aircraft is pulled into the hover
Fly Pilot "C of G okay Hover Checks"
Calls for hover checks in a stable 5' hover
Non Flying Pilot "Flight Instrument Checked, Temperatures and Pressure in the green, CAS messages checked, you are hovering at XX PI, Target PI XX, Hover Checks Complete"
Flying Pilot "Departing"
Smoothly applies target takeoff power
Non Fly Pilot "Target PI Set"
Monitors PI and ensures the correct takeoff power is set
Flying Pilot "Check"
Non Flying Pilot "TDP"
Calls takeoff decision point, TDP, at the briefed radalt for the CAT A profile selected
Flying Pilot "Rotating"
Rotates to -10 degrees for one second and then levels the wings with the horizon on instruments
Non Flying Pilot "Two positive Rates of Climb"
Flying Pilot "Check"
Non Flying Pilot "Airspeed Alive"
Calls airspeed alive when it begins to move
Flying Pilot "Check"
Non Flying Pilot "VTOSS"
Calls VTOSS at 40 KIAS
Flying Pilot "Check"
Adjusts pitch to +5 degrees nose up
Non Flying Pilot "VY - Select 100NR"
Calls VY at 80 KIAS
Flying Pilot "Check - 100NR Selected Confirm?"
Non Flying Pilot "I confirm 100NR Selected"
Flying Pilot "Setting Climb Power"
Non Flying Pilot "Check Climb Power Is Set"
Etc, Etc, Etc
If a loss of power were to occur nothing changes with the calls or the profile. There might be a bit of NR droop initially but it wouldn't be below the minimum limitation if you did nothing with the collective at max gross weight. You would have to regain the NR to 100% passing VTOSS but this would only take a slight downward correction on the collective. The non flying pilot not only has to make the dozen or standard calls within the first 20-30 seconds of flight but also has to monitor for any deviations and be quick to take control if the calls aren't met with an immediate correction or acknowledgement. The list of standard deviation calls that most two crew, multi-ifr helicopter operators use is way more comprehensive than the standard SOP calls listed above on a CAT A helipad departure. The bottom line is this stuff is not hard at all when you train to proficiency. All of us can have our internal gyros toppled departing into a blackhole but if the monitoring, standard calls, deviation calls and a means to take control are all clearly defined this should be a non event. I'm interested to see how accurately the CAT A profile was flown and what calls were made between the flying pilot and non flying pilot from the hover point through the departure. The CVR and FDM data should sort that out extremely quickly. Does the NTSB issue a preliminary finding to rule out a mechanical issue or pilot error like we do in the UK? I know there are several operators that are crossing their fingers the fleet of AW139's isn't grounded due to a mechanical issue. This is still sounding like a classic CFIT(W) case with a flight crew that wasn't given the opportunity to maintain proficiency.