Saturday, April 26, 2014

Night Flight Into Clouds

The rule of thumb is that when you fly into a cloud while flying Visual Flight Rules (VFR), which means without instrument training so that you must always see the ground, then you have very little time to get out before you go into a graveyard or death spiral. Ya, it's bad.

A pamphlet from the Canadian Department of Transport directed at pilots tells the story of how you have something like 117 seconds to live when you fly into a cloud bank as a VFR pilot. It goes something like this:
  • 0 seconds: fly in, hope to pop out, waiting 10 seconds, nothing, still in cloud.
  • 10 seconds: Start to bank and perform 90 degrees turns in a zig-zag to get out (it's been a while so look it up for real if you want to exact pattern)
  • As you do these turns your inner-ear will tell you that you are still turning when you have leveled out. If have to trust your instruments since your body is lying to you. The sensation is a little like spinning in a circle and then stopping and you get wobbly. So imagine you have no ground pushing against you to tell you which way the ground is, you ear is telling you to keep leaning as you try to stay/walk straight and you get the idea.
  • If you refuse to trust your instruments, begin Death Spiral scenario as you refuse to trust the instruments based on what your inner ear is telling you and shortly later you smack into the ground and are an ex pilot.
I got to have first hand experience with this during a night flight. My instructor was on board in the co-pilot seat and a friend was in the back. We left St. John's, Newfoundland and Labrador and headed towards Clarenville on a cross country flight as part of my night rating. This was going to be a multi-hour flight, about 3 hours I think, of flying.

Being night time and VFR we were flying along the Trans Canada Highway, pretty much, since we were staying over land on the flight. During this time my instructor was quizzing me on which towns we were flying other. At night this is hard since a couple houses can look like a town and a town can be so spread out in Newfoundland that it is hard to tell where one starts and another ends.

We had just flown over Seal Cove and it was a clear night. Things were going great. The weather report said clear skies across the island. Awesome, a great night to fly VFR.

Then everything outside disappeared. All you could see out the windows was the glow of our lights in cloud. It was surreal but we kicked into our set of maneuvers to get out. First we gave it a couple seconds flying straight to try to fly through. This did not work.

So, the next step was to try to work our way out of the cloud. First a right turn of 90 degrees, then a left of 90 degrees. Still nothing, still in cloud, no view of the ground. My instructor was watching the instruments intently and walking me through the correct use of my instruments. Telling me to trust them and not the sensation in my ear/head telling me we were still turning once we had stopped our bank/turn and were flying straight.

We did another 90 right and then 90 left and popped out briefly from the cloud bank. During our brief view of the ground we also caught sight of a cloud bank that blotted out the sky and a large amount of the ground that ran north-east to South-west from our position, cutting our route off in a bank of clouds.

We then entered more cloud. Only about 5 minutes had transpired but they were intense, stressful, and a totally new experience learning to ignore what my body was telling me (we are turning, due to inertia in my inner-ear) which would put us into a death spiral if I paid heed to it. Instead we trusted our instruments and began our series of turns again.

This time one 90 degree right and we were out again. My instructor said enough, I had learned a ton, a ton most don't get to learn during VFR night flight training, it was time to changes our plans. I agreed and we turned away from the cloud bank and traced a route avoiding the cloud and heading in the opposite direction.

We radioed in the cloud bank to the tower and changed our flight plane to return to St. John's in a round about way to get more flying in. Then on landing we had another good time but that is worth another post for another time.

For the cloud bank, without my IFR trained, level headed instructor, I have no idea if I would have gotten out of that cloud. It was one intense time being in that groundless glowing world with no sense of up or down, with him coaching me through it. Without him it could have been much worse than a stressful flight.

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