Flying an R44 with an instructor to a distant airfield to meet an examiner for my annual re-validation when the warning lights started coming on and the gauges on the panel started going crazy. I thought the FI was pulling circuit breakers to test me, as my examiner on my initial test had done.
I asked him to stop messing with the breakers, and he said he wasn't doing anything.
A quick Oh Heck moment was followed by an immediate precautionary landing in a field next to a road to aid recovery.
After rapid shutdown we discovered the regulator completely burnt out. Being in the middle of nowhere with no mobile phone signal, we walked across the fields to the nearest farmhouse to call the maint org and await the engineers arrival by road.
The engineers came out and performed a temporary fix so we could fly it to the maintenance base, about half an hour away.
With a train ride home, I was glad I had dressed in my usual outdoors gear, and sensible shoes despite the summer heat, whereas my FI had shorts, vest and flipflops on, not good for walking across fields or travelling on public transport.