Primarily for general aviation discussion, but other aviation topics are also welcome.
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By Dave_Ett
#1517409
Having read the thread with the excellent video about climbing into cloud, it made me wonder what you SHOULD do if you find yourself in cloud during the climb out.

We're taught to call mayday and do a 180, but how safe is that when you're effectively turning back over an active runway, with possibly someone else now trundling down the runway since you've departed the ground?

Should you carry on to safe (circuit?) height on departure heading before you do a 180?

Should you stick to the drills and "fly blind" into a circuit pattern whilst telling ATC about your change in plans?

Should you descend again in the hope of getting back below the cloud whilst telling ATC about your change in plans?

One final question: Should you tell ATC if you do encounter a significantly lower cloudbase than promulgated?

I've done a solo circuit where I stopped 100 feet below circuit height* to avoid flying in to cloud. That was safer than the alternative, but I didn't tell ATC - should I have done?

* given the accuracy of a 1970's altimeter and the medium through which we fly.
User avatar
By mo0g
#1517421
Circuit height wont usually be the minimum safe circuit height, airfield ifr approach plates will show an obstacle clearance height (OCH), and there are also 'circle to land' heights (where the required runway is different to the runway with ILS), which will be lower than the published circuit height.

So basically it depends on your airfield which height would be safe to level off and do a lower circuit to land again.
#1517422
Aviate, Navigate, Communicate..

The biggest danger initially is losing control of the aircraft, establish an instrument scan. Wings level, safe speed. If you are in light cloud, and still have sight of the ground initiate a descent. If not it would be better to continue climbing.

The second danger is bumping into terrain, obstacles, other aircraft, controlled airspace etc. ATC maybe able to help you if they have radar, or transfer you to a neighbouring unit. They can't fly the aircraft for you though so primary attention needs to be on that. Let them know you are in difficulty.

What goes up must come down.... You need to find a safe way back to a runway. The cloud maybe localised and once above or through it you may find a safe gap, other pilots on frequency maybe able to tell you of an area which is clear of cloud. ATC maybe able to steer you to a clear area or assist with a descent to a safe altitude in the hope of becoming visual. You may have to divert to an airfield with better facilities or better weather..
User avatar
By mo0g
#1517424
I just checked the Bristol plates, and they have a circle to land height of 428', for aircraft under 100kts, when north of rwy 09/27.

As an example for the airport in question.
#1517425
Only slightly confused by this one, so your at an airfield and sitting at the threshold waiting to T/O, and ahead of you in the climb out is a big old CB so you climb into it then shout "mayday"?????? Or maybe the WX was so bad you couldn't see it....
User avatar
By mo0g
#1517435
ok, assuming you do not know whether this is a transient situation or not, ie its an isolated cloud or a thin layer, the first step would be to stop climbing and maintain level flight, then when that is done, if you know ahead is ok for ground clearance start a slow steady descent again to get back in visual contact with the ground, and then 180 back to the airfield to land again. If you are not sure of the ground clearance ahead, once the climb had stopped, do a rate 1 180deg turn, and then when done, do that slow descent.

We do 180deg turns on the PPL syllabus, I can't remember if we do climb/descent in cloud, but even if we do, Im sure we do not do climbing/descending turns. Hence stop climbing, turn if necessary, descend.
#1517438
I've done a solo circuit where I stopped 100 feet below circuit height* to avoid flying in to cloud. That was safer than the alternative, but I didn't tell ATC - should I have done?


Doesn't this tell you something. flying in WX that reduces circuit height. this answers your own questions I think.
#1517448
I've done a solo circuit where I stopped 100 feet below circuit height* to avoid flying in to cloud. That was safer than the alternative, but I didn't tell ATC - should I have done?


I have found myself doing that as well. Bad planning etc; this was at Compton Abbas and the cloud didn't lift until about an hour afterwards. (we had the most glorious flight home!)
As we approached we were below the cloud base but also below the promulgated circuit height, as I initiated a climb to the circuit height I realised I would enter cloud. I levelled off and did a circuit about 100/200 feet below the normal height to stay in VMC and told A/G (and others on frequency) what I was doing. To make sure, I repeated the 'at xxx feet on the QFE' statement for each position report. In terms of terrain clearance there was no issue. Of course, with CA being a VFR only destination. the chances of anyone dropping down from the cloud cover was low and I dare say I paid more attention to the radio to hear what others were doing than I did peering up into the cloud deck.
Of course, with the weather being what it was, there was noone around so the entire thing was completely uneventful.

I do think that being vocal on the RT in situations like that is a good thing. By staying VFR and in sight of the airfield, you are aviating and navigating and should be able to communicate. Trying to do a circuit in IMC with no training or approach procedures when there's clear skies 100-200 feet below would be madness in my book.

You mention ATC - if there really is full ATC, then you are obliged (of course, not at the expense of flying the aircraft!) to tell them when you do something they are not expecting. Also, they can then make sure that, if yo do end up trundling around below a cloud cover, no other traffic drops on top of you. Not quite so easy with AFIS, A/G or Safetycom, so you could argue that it is even more important to be active on the Radio so others know where you are. But the chances are that, unless the airfield has IAPs, there will be very little traffic around and that any traffic will be VMC - i.e. below the clouds just like you.

Morten
#1517457
Dave_Ett wrote:Whatever. Please help with my questions, not dissecting the litany of errors going back to my birth which caused me to be in the wrong place at the wrong time. :)


Ignoring the smart ar ses:

There is a much trumpeted (and by some discredited) video out there on youtube called '178 seconds to live', which says rather dramatically the non IR rated pilot on entering IMC will die in 178 seconds.

While a bit over dramatic it's worth a look:

First priority is to fly the aeroplane and ideally to note immediately the height at which you entered IMC.

If this is well above known obstacles in the area (If your local base you should know these)your aim next is to get back on the ground as soon as possible: provided-

Get onto instruments straight away and initiate a gentle descent: if this rapidly brings you back to VMC. level off and turn into the circuit and do a low level circuit and land.

Note a 180 deg turn does not put you on a collision reciprocal to traffic daft enough to depart behind you.

Doing a gentle 180 deg turn without descent should bring you back into the VMC you've just left: bad weather circuit again and land.

If the weather has really closed in ,like you've taken off with 1 or zero dewpoint gap, then, while keeping on instruments fly straight and level , and talk to someone. (last -departure- station or 121.5).

What happens next depends on so many variables, but getting on the ground sooner rather than later should be your aim.
#1517459
Dave_Ett wrote:Whatever. Please help with my questions, not dissecting the litany of errors going back to my birth which caused me to be in the wrong place at the wrong time. :)


If in the early universe hydrogen atoms had been slightly heavier, you wouldn't have been there (Sheldon)

If you've climbed into cloud, as opposed to flown into the side of one, close the throttle and descend - you'll be out again pretty quick. Make sure you know where you are and plan a return to the airfield. Start the plan. When you're happier, and not before, tell ATC what you're doing.

I let a student climb into overcast that was lower than we'd expected once. I was distracted for a moment, I forget why. After we'd descended the conversation went like this
- didn't you see the cloud?
- oh yes
- well why didn't you stop the climb before we entered it?
- you said climb to 1000 feet, so I did

We both learnt something from that!
Pete L liked this
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