I'm a fixed wing pilot. First some data, then some questions for the helo pilots here...
METARs and PIREPs around the time of the crash show the marine layer bases were around 1500' and tops around 2500', with marginal visibility:
KBUR 261753Z 00000KT 2 1/2SM HZ OVC011 12/09 A3016 ; KBUR is 778 MSL so suggests bases of 1800' or so.
KVNY 261751Z 00000KT 2 1/2SM HZ OVC013 12/09 A3016 ; KVNY is 802 MSL so suggests bases of 2100'
KCMA 261755Z 03003KT 4SM HZ OVC017 15/11 A3019 ; KCMA is 77 MSL so bases of 1700' or so.
CMA UA /OV 08002/TM 1620/FL012/TP RV8/SK BASES AT 013 TOPS AT 026
SNA UA /OV KSNA180005/TM 1715/FL027/TP B737/SK OVC027-TOP
LGB UA /OV LGB200005/TM 1748/FL022/TP DA42/SK OVC012-TOP022
According to the USGS Topo maps I have of the area, the highway elevation along the 101 tops out around 1100' just to the east of Las Virgines Rd, with hills up to 2000' to the north and south. Approaching Las Virgines, the highway dips into a valley and is at about 760' elevation. Two private helipads in the area are charted at 850' and 888'. Further west, the highway rises back to around 900' before descending through the Conejo Grade towards Camarillo.
Tracks posted upthread show N72EX was following US-101, at an altitude around 1200'. This suggests they were flying in hazy conditions just below the cloud deck. While the conditions were certainly marginal, they appear to have done just fine following the 101, and had already passed the highest portion of the highway along their route. (The south/east-bound turn started west of Las Virgines)
Assuming the FR24 and FA data are to be believed, N72EX then turned to the south/east, and possibly started a climb before the crash. My questions:
1) Are inadvertent IMC procedures the same for helos as fixed wing - that is, doing a 180? I'd imagine there are more options including trying to slow, hover, or try to set down short of a cloud bank if one sees it looming, or is that not practical?
2) What is the maximum climb capability of the S-76? (i.e. how long to get on top of a 1000' foot cloud layer, if required)
Putting it differently:
3) Are there any circumstances where a helo pilot would choose to turn and climb like that, knowing it would put them into a cloud especially if they weren't already?