Blade Icing in Ice Fog
Thread Starter
Joined: Sep 2004
Aviation Qualifications: ATPL(H)
Posts: 2,378
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From: Canada
Blade Icing in Ice Fog
A friend and I were talking of the old daze and he sent me this picture of Ice on the blades of a Bell 47.
I think it may be an eye opener for some folks.
Imagine the effect on smaller profile blades.
I have included his remarks.
"Blade icing on Bell 47 G4A CF----, January of 1976. I happened to time myself from entering the ice fog, which rolled in behind me over camp when I was out dropping off a crew, 3 minutes!
When I landed back at camp on the lake I could not move the helicopter to reposition, couldn't get enough RPM.
That's when I shut down and took this photo. It's not like I wanted to go
all the way back to camp, there was just no other place to land between camp and crew drop off point."
The effect on powered flight is bad enough but it goes without saying that in the event of an engine failure ice build up would have made an autorotaion impossible. A lesson for us all.
I think it may be an eye opener for some folks.
Imagine the effect on smaller profile blades.
I have included his remarks.
"Blade icing on Bell 47 G4A CF----, January of 1976. I happened to time myself from entering the ice fog, which rolled in behind me over camp when I was out dropping off a crew, 3 minutes!
When I landed back at camp on the lake I could not move the helicopter to reposition, couldn't get enough RPM.
That's when I shut down and took this photo. It's not like I wanted to go
all the way back to camp, there was just no other place to land between camp and crew drop off point."
The effect on powered flight is bad enough but it goes without saying that in the event of an engine failure ice build up would have made an autorotaion impossible. A lesson for us all.
Joined: Jun 1999
Posts: 146
Likes: 0
From: Norwich, CT USA
Looks like rime ice to me. Not a good place to be, but since you took photo's nothing much happened other that some thing to file away for future use. Hard experience gained. You could play all kinds of what if's with this one, What if the rate of icing was faster than it was? What if I had to fly another 15 min to get to a safe haven? And on and on and on. You are still here, thanks to a very good Helicopter, the Bell 47 and some luck. You were very lucky that day.
