Drone vs manned helicopter, UK rules?

[MartinKS]

Immediately after a short VLOS flight this week a police helicopter thundered overhead moving very fast and appeared to be quite low. I'd heard the rotors before, but couldn't have guessed where it was coming from or how far away it was because it was quite echoey and muffled.
I'm pretty sure that if I was still at 75m flying perfectly legally when I was first able to see the police helicopter, i wouldn't have been able to get out of its way. Unless I were able to do something stupid like complete freefall.

Would any collision have been my fault? What am I supposed to do in such situations?

 

[gnirtS]

Would any collision have been my fault? What am I supposed to do in such situations?

Yep, completely your fault.
A drone operator is *ALWAYS* responsible for maintaining separation and avoiding a collision with manned aircraft.
As to what to do, get down low (but not so low you lose signal triggering an RTH climb!) and bring it back in. Given its illegal to fly outside line of sight anyway the drone should never really be more than 400-500m away so can be "home" in under a minute.

If its something "passing through" i'll hover at 30m or so until its clear. Something like a police helicopter that might be lurking in the area for a while with an unpredictable path, the drone is going to come home and land.

It's worth noting as well that manned aircraft also appear a lot lower than they actually are. Usually they're at 500ft or above unless its a special circumstance. You probably had a lot more altitude clearance than thought.

 

[MartinKS]

Fair enough. Would have been no avoiding it then, had maybe 5 seconds between first sight and when they were overhead, 3 more and it was gone. In 5 seconds i could have descended 5m, which wouldn't have made a difference.

 

[gnirtS]

Realistically no they wouldn't but legally you'd still be responsible. However, most manned aircraft are actually higher than people think. People under estimate altitude all the time.
If you KNOW something is likely to be in the area low level don't fly but as you said, sometimes they surprise you and popup suddenly. Its one of the reasons VLOS is a legal requirement - you get more time to see conflicting traffic.