Sorry guys I've been away but many thanks for the feedback.
Widgeon - it is a Breeze Hook and thanks for the links, I'm double checking with engineering that we do all that is suggested following the US safecoms.(I'm 99% sure we do).
MBJ - No Radhaz around the 2 different locations 100nm apart.
Shawn - Static wasn't a problem, no rain, hail, snow,lightening,dust or low cloud. Having said that I've flown in all of these weather conditions before in the same aircraft in exactly the same configeration around pylons and mobile phone masts and have never ever had a problem.On my test flights afterwards I had all the lights on as usual and also transmitted on the marineband and airband comms with no adverse effect. The hook /eye problem, yes I'm aware of that situation and it wasn't a factor.
Lu- You're just getting me worried now
Prior to the first incident the hook had been removed for a filming sortie with a Wescam.
On the first job I lifted 3 loads successfully, the 4th was 900kgs of fertilizer,100% torque was pulled, positioned directly over the load with a 15-20kt headwind an easy lift,no hassles anticipated and before it came off the ground the the lifting gear just dropped away.
Second day- replacement hook new location - trickier job longer line into small clearing through a tree canopy- light winds and a lighter load around 500 kgs. 1st lift of the day, with a normal lift and transit to a hover,then as I was lowering the load into the clearing the lot went.
I've always flown with the electric release armed, and Ive had my finger hover over that button on a number of occasions in the past for various scary reasons but not on these two occasions.
Thanks again
arm the floats
edited for spelling