Menu Sign In Contact FAQ
Banner
Welcome to our forums

VFR Pilots - flight into cloud.

I'm curious what the practices are around the world on this one.

Historically, the practice in the UK as I understand it was to teach that if a student goes into cloud inadvertently, they should do a 180 degree turn carefully and fly out on the reciprocal.

I was involved in a simulator trial a few years ago where we deliberately put a lot of volunteer pilots into cloud without warning. Of those who attempted this, a significant proportion (~40% from memory) lost control of the aircraft. Of those who attempted to fly out straight / descending, none lost control.

I tried this today with a student I was teaching "instrument awareness" to for a VFR licence (NPPL(SSEA) in UK terminology), and taught the gentle descent method - which he flew adequately and safely. I then had him under the hood attempt the 180 degree turn - by 60 degrees, despite careful briefing, he'd lost control and I had to take control back and recover the aeroplane. Fine so far as I was concerned, as it got the learning point across well, and I'm confident that in the future, he'll stick to wings level / shallow descent, which I believe (and is also policy at the school I teach at) is the way to happiness and survival.

What's going on anywhere else? What's anybody teaching, and the justification for it?

G

Boffin at large
Various, southern UK.

I was involved in a simulator trial a few years ago where we deliberately put a lot of volunteer pilots into cloud without warning. Of those who attempted this, a significant proportion (~40% from memory) lost control of the aircraft.

I'm sure this is true and I have seen numerous studies which have similar results....however I have never understood why...when I learned to fly my instructor put me under the hood at any opportunity and on occasion we flew through cloud layers and even from the beginning never had a problem...I know this is heresy, but it really isn't that difficult to keep the plane upright by reference to the AI

YPJT, United Arab Emirates

I think that's the point. It isn't that difficult to keep the woodworking tool upright - but turning whilst staying under good control is difficult for anybody who hasn't had significant IMC instructing.

G

Boffin at large
Various, southern UK.

The times I've come closest to flying into cloud inadvertently are when I have been cruising just under the cloudbase - e.g. one day when the cloudbase was only 1500 feet. I wouldn't have called it scud running, but I wanted to keep as much air below me as I could. In this circumstance, maintaining altitude and doing a 180 isn't going to help matters at all.

In my PPL I did some upset-recovery in IMC and a simulated vector approach (with my instructor giving the vectors). I found flying by instruments relatively straightforward, and assuming my instruments remained working and conditions were reasonably smooth I like to think that I could probably get myself out of an inadvertent-IMC situation. My instructor commented that this was the one occasion when having spent far too much time on flight simulators might have stood me in good stead.

So, I wonder how well people normally do when they're doing instrument flying in the PPL? Could it be that the limited amount of instrument training just leads to overconfidence? I'm hoping to take IMC lessons soon, rather than finding out that I'm one of the 40% on my own.

Here (France) we're taught to fly a 180 turn, bank angle no more than 10 degrees.

Bordeaux

I guess the danger of the gentle descent method is that you have to teach a decision-making process in order to use it safely. Obviously there are some circumstances where it is inappropriate if not dangerous. The advantage of the 180, if properly executed, is that it should almost always be safe in respect of terrain. I agree that it's a more difficult manoeuvre.

Not that it always gets you out of trouble, though. Two VFR pilots I know ended up in IMC over South Wales. They successfully managed to perform the 180, both of them monitoring the instruments, but the cloud had closed in behind them. After heading west for a few minutes, they realised that it wasn't clearing. Fortunately, Cardiff Radar were able to vector them a few miles south, and the cloud cleared over the coast (as it often does) so they were only in IMC for a few minutes. Apparently it felt like a lifetime, though!

EGBJ / Gloucestershire

the gentle descent method only works if there is a decent cloud base under which one can continue visually. Enough terrain clearance - so to speak. But often cloud bases are very low, perhaps hanging on uphill mountain slopes etc., and a controlled forward descent would end in a crash. CFIT. I think it is really better for a pure VFR-pilot or beginner to invest into training a 180 turn under the hood. Spend your money first there and afterwards buy the glass cockpit :-)

EDxx, Germany

I am not suprised that flying straight ahead in IMC is far easier than doing a 180 level turn, but perhaps the reasoning behind the 180 was that you should end up more or less on your previous route, which was "obviously" clear of terrain because you have just flown it.

Whereas if you just fly straight ahead, you might

  • stay at present altitude and hit something, or collect ice
  • descend and hit something before reaching the cloudbase
  • climb and hit something (or ice up, or bust CAS) before ...

Personally I would always fly straight ahead but that's because, from day 1 after the PPL, have always flown with a decent GPS moving map, but most of the principles in today's PPL training go back to WW1, with some concessions to WW2

Also the VFR/PPL industry has seemingly tried hard to avoid suggesting that any extended flight in IMC is feasible, hence the immediate 180. If you tell people that actually they can fly on straight ahead, that conflicts with that principle.

IMHO, VFR and IFR flight training should be rolled up into one, at some basic level of capability (because clouds and poor vis are not exactly uncommon) but there is no way to package that into an ICAO compliant product. I believe it was successfully tried in the USA, with a ~ 50hr "PPL/IR" but I haven't heard of it going anywhere.

Administrator
Shoreham EGKA, United Kingdom

Also the VFR/PPL industry has seemingly tried hard to avoid suggesting that any extended flight in IMC is feasible,

I think that's what I was getting at below, I didn't just mean I found straight and level easy, but turning as well...and I think this is because my ab initio instructor didn't try and spook me with horror stories about immediate death if clouds are entered....instead he got me comfortable with real and simulated IMC...

YPJT, United Arab Emirates

Personally I would always fly straight ahead

I think that's OK if you're used to flying in instrument conditions, but with, or without a GPS, a inexperienced pilot suddenly has a lot of extra mental stuff to deal with, and they still have to become visual ASAP. There is no guarantee that you will soon again become visual at that same level by just flying straight ahead.

I flew to Leicester yesterday, and at 2300ft not long into the flight I hit a wall of cloud. Having an IMC I climbed out on top to 4000ft (checking for ice of course), but as a non-IMC PPL in this case my only option would have been to do a 180 as safely as I could and be back in visual conditions. The descend in a straight line would generally be my preferred option, as a 180 is dangerous untrained on instruments, but in this case the cloud base in front was now 1500 ft, and not far away there was a mast at 1000 ft. If you dont know where you are, and whats around, you might descend too low, into something you dont want to.

For me, I think it also comes down to planning. If you read the METAR's and TAF's for the area around your route, you are invariably going to see low cloud might be a problem, and you should try and make a judgement as to whether you do the 180, or the straight descent. I dont think you can only train and practise the one method.

62 Posts
Sign in to add your message

Back to Top