VMC into IFR accidents?

[liam548]

I am not disputing the figures, such as a typical VFR PPL pilot will only maintain control for a few minutes but my question is why?

I mean even without an IMC or IR surely the pilot can look at instruments and determine is he climbing/banking etc so how does he end up in a spiral dive so soon? Is it due to the extra factors of actually flying through the cloud rather than just losing sense of his orientation?

Just trying to understand a little better...

Liam

[Fright Level]

Read Chapter One of the FAA Instrument Flying Handbook (http://www.faa.gov/library/manuals/aviation/instrument_flying_handbook/) and study the issues such as spacial disorientation, coriolis illusion, the leans etc and you'll see what traps lay for the unwary/untrained pilot even if they think they know how to interpret standard instruments.

Also, I think you meant VMC into IMC accidents? Changing flight rules shouldn't cause an accident but there is common, in fact widespread, confusion between the terms VFR/IFR and their relation to VMC/IMC conditions.

I've often flown into IMC on a VFR flight and fly VMC on an IFR flight for most of the time.

[Gertrude the Wombat]

Get an instructor and an aeroplane and go fly in cloud, preferably some nice bumpy cumulous, if you can find an instructor willing to sit on his hands with his mouth shut until he has to do something to save your lives. For added fun, do this near the edge of some controlled airspace, or a mountain, or something.

If the instrument training part of your PPL was done with something other than real cloud, eg foggles, you will have no idea what IMC is like - there are just too many visual cues, you aren't really relying on instruments at all.

[vee-tail-1]

G the W
I did just as you suggest in real cloud with bumpy bits. Frightened the bul***t out of me! A really good exercise for someone who thought he could cope. :eek:
My ATL has a strictly day VMC panel, and even if it had full instrumentation my lack of a suitable IR would almost certainly result in a bad outcome if inadvertently going IMC.
Has anyone here tried the E-Gyro microhorizon which gives an unconventional led light display? It just might be a life saver for those of us who are not up to speed with instrument flying on conventional instruments.

[gooneydog]

Add to that the "comfort" of realization that If I don't do this right I will die can make a heap of difference

[dont overfil]

Gertrude I wholeheartedly agree with you but there are instructors out there who can't fly in cloud. They've got a bloody CPL but no IMC or IR! How sensible is that?
DO.

[Fuji Abound]

I think this is an excellent question.

The popular myth is that the average PPL will last less than a minute. Reliance is placed on a study that was conducted in the States. The myth is not true, and nor does the study support the myth.

In fact with the instrument training a PPL is meant to receive these days the average current PLL would not do too badly.

However, (and it is a big however) the ability to fly on instruments is all about being able to fly a full sector entirely on instruments, in less than benign conditions and cope with a instrument failure or two.

So, back to your question.

Instrument flying is tiring. Even for old hands it requires a lot of concentration, although it does get a lot easier with practice and an autopilot. I recall a four hour trip that for various reasons was nearly on instruments the whole time entirely hand flying - the aircraft did not have an autopilot - I am happy to admit I was pleased to be on the ground at the end of it.

It is tiring because it involves a high degree of concentration. As with anything involving a great deal of concentration it is easy for your concentration to lapse. It is also easy to find your concentration has been diverted.

Imagine you are flying a heading at a constant altitude and able to concentrate fully on the instruments - well you shouldn’t find that too difficult. Of course that is not how it works in the real world. Instead imagine being asked by AT to fly a number of different headings with perhaps an altitude change or two thrown in, after which they abandon you (perhaps after your route took you through an area of controlled airspace) with the infamous “own nav”. All that planning has just gone out the window and you now have to re-work your course, so there is a bit of map reading to divert your attention, in the middle of which things start to get a bit bumpy, the passenger starts throwing up and the AI fails. The last is fortunately pretty rare but the rest is par for the course. Before you know it your scan has broken down and the aircraft is all over the place, or you have descended below the MSA of the new sector in which you are flying.

This is the exact recipe for a loss of control. It is really easy for it to happen. You might think hey I could recover the aircraft - but recovering in IMC is tough. It is real easy for the aircraft to get out of control very quickly. In fact a few moments eye down on the map or rooting around for the sick bag is enough to find as your eyes go back onto the AI you are in a 45 degree descending bank with the airspeed rapidly increasing.

Then there are the leans. Anyone who has flown on instruments has had them. They are difficult to describe. However, when they set in there is no stronger feeling that you are losing control of the aircraft. You would not believe it is possible. It is.

I have tried to describe why instrument flying is more than flying in a straight line using the AI and DI to keep the aircraft straight and level. I have also tried to describe why it is very easy to loose control after you have had some limited instrument training but think it is adequate and cant understand what all the fuss is about. As others have said, there is nothing quite like trying it out with an instructor - for all the words in the world - but hopefully that will help with your understanding, short of trying it with an instructor for real.

For the avoidance of any doubt it really is one of those occasions where the over done phrase is deadly relevant - dont try this at home - you will almost certainly last more than a few minutes, and if it is an out an out emergency with absolutely no other alternatives the PPL training you received might safe your life, but otherwise it really is a recipe for disaster - it will kill you and anyone else in the aircraft with you. Dont try it.

[papa600]

My instructor took me into cloud during training which is eerie to say the least. He also demonstrated how the senses can be fooled by doing a gentle left bank for 1 minute in cloud then fly straight and level - instruments tell you you are level your brain tells you that you are banking right.

Its obvious how quickly it can all go pear shaped but I agree with liam 548 - the instruments always tell you if you are straight, level, climbing, descending, accellerating, slowing down.

What they don't tell you is what is in front of, below or above you.

[dont overfil]

I did 3 hours instrument training during my PPL some time ago but I think it's only 1 hour now.
DO.

[Mariner9]

Whilst not by any means disagreeing with the usual sentiments of the difficulty/potential dangers of IMC, the fact remains that loss of control in IMC still appears to be a relatively rare event if the monthly AAIB accident reports are anything to go by.

[liam548]

I think this is an excellent question.

The popular myth is that the average PPL will last less than a minute. Reliance is placed on a study that was conducted in the States. The myth is not true, and nor does the study support the myth.

In fact with the instrument training a PPL is meant to receive these days the average current PLL would not do too badly.

However, (and it is a big however) the ability to fly on instruments is all about being able to fly a full sector entirely on instruments, in less than benign conditions and cope with a instrument failure or two.

So, back to your question.

Instrument flying is tiring. Even for old hands it requires a lot of concentration, although it does get a lot easier with practice and an autopilot. I recall a four hour trip that for various reasons was nearly on instruments the whole time entirely hand flying - the aircraft did not have an autopilot - I am happy to admit I was pleased to be on the ground at the end of it.

It is tiring because it involves a high degree of concentration. As with anything involving a great deal of concentration it is easy for your concentration to lapse. It is also easy to find your concentration has been diverted.

Imagine you are flying a heading at a constant altitude and able to concentrate fully on the instruments - well you shouldn’t find that too difficult. Of course that is not how it works in the real world. Instead imagine being asked by AT to fly a number of different headings with perhaps an altitude change or two thrown in, after which they abandon you (perhaps after your route took you through an area of controlled airspace) with the infamous “own nav”. All that planning has just gone out the window and you now have to re-work your course, so there is a bit of map reading to divert your attention, in the middle of which things start to get a bit bumpy, the passenger starts throwing up and the AI fails. The last is fortunately pretty rare but the rest is par for the course. Before you know it your scan has broken down and the aircraft is all over the place, or you have descended below the MSA of the new sector in which you are flying.

This is the exact recipe for a loss of control. It is really easy for it to happen. You might think hey I could recover the aircraft - but recovering in IMC is tough. It is real easy for the aircraft to get out of control very quickly. In fact a few moments eye down on the map or rooting around for the sick bag is enough to find as your eyes go back onto the AI you are in a 45 degree descending bank with the airspeed rapidly increasing.

Then there are the leans. Anyone who has flown on instruments has had them. They are difficult to describe. However, when they set in there is no stronger feeling that you are losing control of the aircraft. You would not believe it is possible. It is.

I have tried to describe why instrument flying is more than flying in a straight line using the AI and DI to keep the aircraft straight and level. I have also tried to describe why it is very easy to loose control after you have had some limited instrument training but think it is adequate and cant understand what all the fuss is about. As others have said, there is nothing quite like trying it out with an instructor - for all the words in the world - but hopefully that will help with your understanding, short of trying it with an instructor for real.

For the avoidance of any doubt it really is one of those occasions where the over done phrase is deadly relevant - dont try this at home - you will almost certainly last more than a few minutes, and if it is an out an out emergency with absolutely no other alternatives the PPL training you received might safe your life, but otherwise it really is a recipe for disaster - it will kill you and anyone else in the aircraft with you. Dont try it.

yes that explanation is useful thank you. I just read some posts on the internet that read like automatically after entering cloud PPL holders with no IMC or IR suddenly lose all control with no chance of sorting it out. Clearly this is not the case it probably takes one or two other factors as well.

I understand better now.

I am keen to do my IR or IMC in the future, that is if the IMC is still aorund, hopefully it will be!!

Liam

[SNS3Guppy]

Liam,

One of the single most challenging, and potentially dangerous things one can do is fly single pilot IFR. There's really no other duty in aviation that requires as much concentration or effort, or has as much potential for loss of control.

One of the most dangeroub bits of advice that can be thrown about is that IMC flight is no big deal. It is. Not just navigating from A to B, not just handling inflight abnormalities such as a partial panel situation (loss of some instruments), but routine, simple, plain-jane maintaining control of the airplane.

The few hours spent teaching reference to instrument flight "under the hood" using a view-limiting device isn't adequate to prepare someone to fly IMC, and it's designed to give rudimentary introduction in the event a situation is allowed to develop in which flight by reference to instruments is required. Such a situation without ample proper training should be considered an emergency...and the truth is that inadvertant flight into IMC continues to be a regular source of fatalities.

There are many reasons for this. Everyone experiences illousions that do not occur nearly as readily during flight under a hood. I experience a sensation of continually rolling to the left. Some people experience other things. I just got done with recurrent simulator training, and even in there I watched professional after professional have challenging moments doing simple things such as maintaining altitude, heading, or flying a basic approach. These are folks flying IFR in the system every day using varying degrees of automation...but in an operation where everyone handflies every takeoff and climb and every descent and arrival. Still there were challenges.

Don't let anybody kid you or fool you about inadvertant flight into IMC. It IS a very big deal and continues to be a killer, just like controlled flight into terrain and fuel mismanagement. IMC flight is nothing to be taken lightly.

[mm_flynn]

Whilst not by any means disagreeing with the usual sentiments of the difficulty/potential dangers of IMC, the fact remains that loss of control in IMC still appears to be a relatively rare event if the monthly AAIB accident reports are anything to go by.


Surprisingly you are correct. Loss of control in IMC by PPLs is not very common (2 fatal accidents in the latest CAA publication). Controlled (Reasonably) Flight Into Terrain on the otherhand is common and remarkably fatal (8 incidents of PPLs doing this in IMC).

[Shunter]

I think one of the biggest problems with VMC pilots flying into cloud is the panic it often incites. The basic training during the PPL is probably sufficient enough for someone to do a 180 and get out of the white stuff. That's about it.

Doing something simple like staying straight and level in cloud for an indefinite period sounds trivial, but to someone who has never learned how to properly scan instruments it will mentally exhaust you very, very quickly.

[Pace]

I agree with the other posters here and also with the post by Fuji. To understand it better I think you have to look at the processes an instrument pilot goes through in instrument training.

On his first sorties with an instructor he may manage to keep control with his full attention on the instruments and the aircraft set up in cruise.

But that takes his full concentration leaving no brain power for any other tasks. Now start loading that already loaded mind and the whole thing falls apart. Try taking your eyes from the instruments and reading and deciphering a map. Or making a radio call, changing nav and radio frequencies, reading plates or operating the aircraft.

In early instrument flying its a bit like riding a bike. As you master one aspect and do not require your full brain power to do so then you find you can start handling other operations until you can fly the aircraft on instruments do the other chores and be miles away thinking about the weekend away with the girlfriend.

It all becomes second nature the autopilot part of your brain takes over the flying while your concious mind thinks about anything but flying :)

How well or quickly a pilot takes to instrument flying also depends on whether you have a visual brain which can take in a lot going on at once. Whether you have good balance and spatial awareness.

I can remember flying as a safety pilot with a low instrument time pilot ina twin. We flew in **** weather and you could see he was struggling. We made an approach and had to miss. I said go around and he forgot everything he had been taught. He pulled the nose up but did nothing to add power clean up the airframe and just froze.
I had to dive in from the right and take control of what would have been a stall spin situation in IMC.

To some it is a natural exercise to other they have to work harder at it. Not all pilots become good instrument pilots we just have different brains and some suit it better than others.

Panic or freezing is an example of when the mind becomes overloaded and can no longer handle the volume of information. Pilots in that situation cannot even recall their own name and I have seen that example in one such pilot. A bit like a computer Graphics Card that cannot handle the data it freezes.
But the more data thats held in the main computer memory the less work the graphics card has to do.

In the non instrument trained pilot the poor little Graphics card is doing the lot and soon locks up.

Pace

[Airbus Girl]

Trouble is there are 2 types of PPL - those that will fly into IMC because they think they can handle it and those that will ensure they stay clear.

Most PPLers I've flown with (and I've done it myself) will have trouble holding a heading and altitude whilst also reading a map/ talking on the radio. This can be fatal in certain situations.

If anyone here is thinking what would they do if they inadvertently found themselves in cloud I would say:-
1. Be extremely aware of the dangers
2. Maintain straight and level flight, and/or climb to a safe altitude.
3. Get on the radio pronto.
4. Tell ATC you are not instrument qualified and ask if there are any clear levels.
5. Climb out of the cloud (or descend if you are sure it is safe - again, ask ATC for help if you need it)
6. Do not be afraid to use ATC to help you as much as possible - this is what a really smart pilot would do. Ask them for reports of conditions, ask them to find out if there are any holes in the cloud you can descend through or ask them to vector you to a runway that is straight ahead of you, or with small heading changes.
7. If this means landing at a major airport, so be it.

I remember a few years back at Stansted, in really really crap weather, even for us in our big jet, and we heard an aircraft get clearance to land. It then took ages to appear. When it popped out of the cloud at about 50 feet, we were amazed to see a Cherokee!!!!!

But, thinking about it, he did the right thing - big airport, huge runway, excellent radar, ATC help, fairly flat surrounds. They could line him up, give him an SRA approach (heights and headings), and help him get safely on the ground.

If you are in the sh*t then don't be backward in coming forward.....

[IO540]

There are however many degrees of difficulty, in any given situation, according to the available equipment.

Instrument flying takes up a lot of one's brain - no matter how good a pilot one is - because one has to be continuously controlling the plane.

A stable plane v. an unstable one makes a vast difference. The two extremes of my experience are perhaps the TB20 and that piece of junk called a Tomahawk.

Then you have nav equipment. One could teach anybody to fly straight and level and hold altitude on instruments with an intensive scan, in maybe 10-20 minutes, and I have done that with a few passengers. But in practice this is not enough because one has to pay attention to other stuff and this detracts from the instrument scan and messes things up unless one is very quick and organised about it. So, doing this stuff with e.g. a big moving map GPS is far easier than doing it with the old gear.

The reason the IR checkride (FAA or CAA) is hard is because they pile on the workload to the point where there is barely enough time to keep track of where one is. If one had time to play, not one thing in the checkride would be hard in the slightest, assuming one knew how to fly the basic procedures.

And a decent autopilot transforms the whole situation totally.

That's why I don't go for the often quoted view that everybody will die within 123.45 seconds of entering IMC.

[Gertrude the Wombat]

I experience a sensation of continually rolling to the left. Some people experience other things.
In my case it's usually a sensation of straight and level whilst gently turning right. Correct it, look away, and I'm turning right again.

[PompeyPaul]

Fuji,

That was probably the best post I ever read on pprune

[steveking]

I'm a PPL on 500 hrs passing nearly 3 years ago. I think I could quite happily keep the aircraft straight and level and follow a track on my GPS in IMC ok, but as for carrying out an approach or coping with a vacuem failure, no thankyou. Sends a shiver down my back thinking about it.

Hats off to the IR/IMC guys, it's a different skill altogether.

Be honest IMC guys how happy would you be in IMC with a VAC failure? I'm not IMC rated so not qualified to say.

[Pace]

Be honest IMC guys how happy would you be in IMC with a VAC failure? I'm not IMC rated so not qualified to say.

To be equally honest not happy but not unhappy :)

Pace

[Keef]

As others have said, it's not easy, and it needs regular practice.

When I did my FAA IR, a while ago, I could cope with navigating, talking on the radio, dialling in new frequencies and headings, swapping approach plates, while keeping within 3 degrees and 50 feet - and having the examiner firing questions at me to see if he could overload me.

There comes a point where you go into overload - maybe when the AI topples, or the engine starts misfiring. Then it gets interesting.

I'm lucky: I don't get the "leans" (or never have, yet). BUT if I'm overloaded, the height keeping and heading wander a bit and have to be recovered when the distraction is sorted. Not good.

I'm much happier flying IFR in IMC with another pilot: one of us does radio and plates, bugs and frequencies while the other concentrates on flying the thing. I've happily flown the length of the UK and across large chunks of California like that.

Single-pilot IFR is tough!

The IMC Rating is very well worth doing - even if EASA are ill-advised enough to do away with it, the skills will help you.

[mm_flynn]

Some years ago according to the NTSB only 4% of accidents were caused by unqualified flight from VFR to IMC.

Dont know if it's relevant:
http://www.pprune.org/private-flying/317076-unqualified-vfr-flights-into-imc.html

Quite relevant, if the whole quote is included. Only 4% of accidents and it accounts for 19% of deaths. As everyone has said, without proper IFR training you may think you can do it, but with everything going your way you still are going to be at 100% effort - anything extra (like navigating) and it starts to fall apart - in a way that is very often fatal.

[IO540]

how happy would you be in IMC with a VAC failure

It depends on what is vacuum powered. It varies from one plane to another.

On mine, for example, only the main AI is vacuum powered. The other one is electric. But the autopilot works off the main AI so if I get a vac pump failure I lose the AP, which is a really stupid price to pay for the plus of having a main AI which will continue working indefinitely (not just for e.g. 30 mins) despite a total loss of electrics. It would have been much smarter for the AP to work off the electric AI but certification issues make this highly desirable safety improvement impossible.

Some planes have a vacuum powered DI. However, it is rare to have a slaved compass system (e.g. a slaved HSI) which is vacuum powered.

This is just one example of why a pilot should have a complete understanding of the aircraft systems - something very much missing in so many cases.

That said, 99% of airways IFR flying is done in sunshine... :) One does the IR so one can sit in sunshine, not in cloud.

[Shunter]

Quite. Mine has a vac AI/DI, but an electric TC which is also the autopilot. In the event of a vac failure, on goes the A/P. I've had a vac pump die on me before, so I know what it's like, and can see the problems it might cause, especially without any kind of warning mechanism (how many people regularly include suction in their scan?). A fast-toppling AI isn't so much of a problem because it's obvious, it's when it topples slowly that you get into trouble.

[Fuji Abound]

That was probably the best post I ever read on PPRuNe

Thank you. :\

I have not yet had the leans using glass - anyone found the same?

[clareprop]

Like a number of people, I did my IMC almost straight after my PPL and the confidence gained was excellent. Together with a friend, we would practise and use the rating carefully, particularly on trips to LFAC etc.
Many years went by and I lapsed in flying, eventually coming back ten years later on the old method of ten hours flying and retakes of most exams. The ten hours was fun and I realised I had lost none of the coordination skills for flying. Life was good and I got back into a share.
I regularly flew across the channel..I mean REALLY regularly as in most weekends with a car left in LFAC.
One midweek, I decided to take a non-flying friend to le Touq. Lovely day with bubbly clouds. Off we went, no problem at all. My friend was very impressed with the clouds and after flying past a few I thought it would be clever to fly through one..pop-in, pop-pop-out. Having selected one, we popped-in....and stayed in..and stayed in. Fifteen seconds went by as I realsied the situation I was in. I then experienced a horrible feeling that I have only ever heard described elsewhere. From my feet to my head came a rushing feeling leaving me with a metallic taste in my mouth and complete weakness. In that second I was more frightened than I ever have been in my life. I started to accept that today was it. I looked at the instruments, desperately trying to remember how to scan. I knew we were level but in my mind (remember this is only 40 seconds or so) fear was racing that I was not going to get out of this. And then, we popped-out.
My passenger was grinning with happiness but I was shaking and continued to do so.
Please don't bother to tell me how stupid I was risking my life and that of an innocent person..I know that.
That incident, which happened years ago affected me deeply and still does. Tasting fear like that let's it out of the box and it comes back from time to time to visit. Some here will understand, other won't.

My message: Don't fly into IMC unless you are trained AND current. For me, it was forty seconds that mentally wrecked me.

[vee-tail-1]

clareprop
I don't think it mentally wrecked you; not if you can express the sensation of fear so eloquently.... and yes been there a few times.

[Pace]

Clare

Sounds like a panic attack maybe claustraphobia at being inside clouds and the thought that you maynot come out again.

I flew left seat in a single with a great guy who had a simular problem. We were flying to Belfast City. He was a good VFR pilot but hated being in clouds.
The weather was 1000 feet overcast. I filed IFR and climbed on top at FL80 where I noticed he was hyperventilating and kept asking to go down as he could not breath.

I told him it was crazy as we were in the blue at FL80 and descending would put us cruising in IMC. ATC may not approve such a level.
He then accepeted it but was very tense until we passed the IOM where the clouds started to break and he got glimpses of the sea below.

As soon as he saw the sea he relaxed and started to enjoy the flight. In the afternoon we flew back with a 3000 foot broken cloudbase and filed VFR.
He took the left seat and was like a man transformed flying really well and back in his comfort zone. The guy is a very meticulous pilot, handles the aircraft well but cannot cope with clouds or being on top out of sight of the ground. I am sure its a more common problem than you realise and you have to identify why you felt like that???

Pace

[IO540]

clareprop - have you ever had that panic feeling with somebody else (or an autopilot) flying in IMC?

Others have on occassions described experiencing something similar.

[Gertrude the Wombat]

Be honest IMC guys how happy would you be in IMC with a VAC failure?

Had one, or at least an indicator light, in IMC on an IMCR lesson.







But the other vac pump kept running so we didn't lose any instruments.

[liam548]

As others have said, it's not easy, and it needs regular practice.

When I did my FAA IR, a while ago, I could cope with navigating, talking on the radio, dialling in new frequencies and headings, swapping approach plates, while keeping within 3 degrees and 50 feet - and having the examiner firing questions at me to see if he could overload me.

There comes a point where you go into overload - maybe when the AI topples, or the engine starts misfiring. Then it gets interesting.

I'm lucky: I don't get the "leans" (or never have, yet). BUT if I'm overloaded, the height keeping and heading wander a bit and have to be recovered when the distraction is sorted. Not good.

I'm much happier flying IFR in IMC with another pilot: one of us does radio and plates, bugs and frequencies while the other concentrates on flying the thing. I've happily flown the length of the UK and across large chunks of California like that.

Single-pilot IFR is tough!

The IMC Rating is very well worth doing - even if EASA are ill-advised enough to do away with it, the skills will help you.


can someone explain the "leans"?

[C172 Hawk XP]

Complex subject, but look here for an introduction :

Sensory illusions in aviation - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Sensory_illusions_in_aviation#The_leans)

[Fuji Abound]

That is about the measure of it, except that description gives the impression the pilot starts leaning!

What actually happens is you are overcome (yes, that is the best word for it) with the sensation that the aircraft is turning left or right so you desperately want to compensate with the yoke or stick.

The instruments of course are telling you something quite different - it is bit like being smitten, your senses tell you one thing and your brain something different - you have to hope your brain gets the better of you!

With training you brain does get the better of you, but it is still the most weird sensation.

I wonder how much research has been done. On the few occasions I have had it happen to me there is some commonality. It has always been at the beginning of a flight, and always following a low(ish) level entry into IMC. It usually last for a few minutes and I find it to be a really powerful and distracting sensation even adopting the usual tricks to disperse the feeling.

I have never had it flying a glass system and never at night, but I guess there is always a first time. I also have not had it happen for some time, although I fly less on instruments now than I use too.

I also wonder how many people never came across it during their instrument training but have subsequently. I count myself lucky that I did (experience it during training). It was a comfort to see a nod of the head from the old boy in the right seat, a smile playing on the edge of the lips, and a sanguine, "ah yes, that will be the leans then, lad".

[dont overfil]

Do you think the shape of the glareshield can influence the onset of the leans? I get it occasionally in a PA28 which has a curving glareshield but can't recall being affected in a Cessna which is flatter and higher.
DO.

[IO540]

The "leans" is something which results from the balance organs feeding information to the brain stem, and thereafter it gets processed into what amounts to an illusion of (wrong) movement.

AFAIK much depends on the orientation of one's head. For example it is advised that one should not look down (e.g. to look for a lost pencil) when instrument flying.

It's quite possible that keeping one's head more upright might help somebody...

Personally I don't get the leans at all. But I would also not depart on any significantly long trip, with IMC potential, single pilot, unless the autopilot was working. It's hard work, if nothing else.

[C172 Hawk XP]

Personally I don't get the leans at all

It might be truer to say that you have not, so far, experienced the leans ! Nobody is immune. Given the right semicircular canal movements and reversals it could happen to everyone !

[Pace]

The answer is to believe your instruments and to keep a good scan going confirming what each instrument is saying and backing up each instrument against others.

Remember too that only you know the aircraft is in cloud the aircraft doesnt. As far as its concerned it may as well be in perfect visibility and in sight of the ground.

Ie you can fly quite happily with a trimmed out aircraft with your hands off the column and squeeze the rudder pedal to hold heading.

You can do the same in cloud so let the aircraft fly itself, relax and let it do the work for you.

Cloud density also plays a part. Some is so thin its easier to get a horizon of sorts from the light and shade in the cloud.

Other cloud is so dense you can barely see along the wings.

Equally on top of cloud you can get illusions with the cloud which make you feel you are not level with the horizon.

cloud can have a slope where you attempt to level using the slope as a horizon and again doubt the instruments. Again the answer is getting a good and natural scan and checking one indication against another to confirm its the instrument that is not faulty then make the instruments your no 1 trust item.

Peering in and out doesnt help as that will confuse what your visual mind is tricking you into seeing and what the instruments are telling you what is happening. As soon as you doubt both your building trouble for yourself.

Flying through very heavy streaming rain or even worse heavy snow is something to experience and the only answer there is instruments intruments instruments :)

Pace

[steveking]

That said, 99% of airways IFR flying is done in sunshine... http://static.pprune.org/images/smilies/smile.gif One does the IR so one can sit in sunshine, not in cloud.

Your making me jealous.:)

I like nothing better than sitting above the cloud in the sunshine in the smooth air. I do find it a bit irritating when the holes start to disapear and have to make the decision to descend or not. Even worse 10 miles later travelling underneath the holes start appearing again. Lucky enough my aircraft can give me 2500fpm so the up bit doesn't take to long.

Oh well life of a VFR pilot ehh. Must get round to doing that IMC one day.

When I was talking about a VAC failure I suppose I was thinking of the school PA 28 and losing their AI, DI and no autopilot.

The autopilt in my RV6 is pretty basic but has it's own internal attitude reference and gets headings from the GPS.

[Fuji Abound]

When I was talking about a VAC failure I suppose I was thinking of the school PA 28 and losing their AI, DI and no autopilot.

I have come across aircraft with a vac AI, turn and slip and DI certified by the manufacturer for IFR ops. I have even flown them in IMC. It is bl**dy dangerous - as a minimium the aircraft must have an electric turn and slip.

However, that said flying an aircraft in IMC with a turn and slip and a magnetic compass is, as far as I am concerned at any rate, an emergency. Flying an IAP by hand in that configuration is challenging however good you think you are. We have all done it, if hopefully without an actual failure, but if instrument flying is challenging you have moved into the territory that lies between an aircraft carrier landing and advanced level aeros.

[IO540]

However, that said flying an aircraft in IMC with a turn and slip and a magnetic compass is, as far as I am concerned at any rate, an emergency. Flying an IAP by hand in that configuration is challenging however good you think you are. We have all done it

Yes, it's called the FAA IR checkride :)

Just to make sure you are sharp, it's done after a 3 hour oral ;)

[Fright Level]

On my last SPA IR renewal, the examiner "failed" not only the horizon, HSI & RMI but the magnetic compass too. I did an approach and ILS to 200 feet with just the altimeter, VSI and turn/slip indicator.

The controller vectored me with (standard rate) turn instructions "start turn", "stop turn" until I was established on the localiser. It was good to see just how little you really needed to get in on a bad day but it was bloody hard work!

It's called a "no gyro, no compass approach" and apparently all radar controllers can carry out one.

[172driver]

To demonstrate how your senses can - and will - fool you, my instructor did the following (this is for the FAA PPL). On one of our night flights (for various reasons I did quite a lot of my initial training at night), we were in real IMC, climbing out of the L.A. basin. While in cloud he momentarily dimmed the instrument lights. After what seemed like an eternity, flicked them on again - I was in a 30 deg bank after what was probably only a few seconds. Trust the instruments!

Next up in the lesson came the strobes to 'on' in IMC to show the effect they have while looking through the prop...... :E

[Pace]

SteveKing

I wish you could rely on being in the blue but sadly that often is not the case.
Especially in a twin or single you may not be able to get on top or have to stay at a level where you dont get the dreaded ice.

While its great punching out into the blue and sunshine often you can takeoff into a 400 foot cloudbase fly 200 nm with nothing and punch back out at 400 feet the other end.

Be prepared for the worst and you may get the the best expect the best and you may have to deal with the worst :)

Pace

[IO540]

I wish you could rely on being in the blue but sadly that often is not the case.
Especially in a twin or single you may not be able to get on top or have to stay at a level where you dont get the dreaded ice.

While its great punching out into the blue and sunshine often you can takeoff into a 400 foot cloudbase fly 200 nm with nothing and punch back out at 400 feet the other end.

Be prepared for the worst and you may get the the best expect the best and you may have to deal with the worstYou've stumbled upon a major IFR flight planning issue, Pace: where are the cloud tops?

There seem to be two kinds of pilots: those who will scrap a flight if IMC (which is usually freezing, at Eurocontrol airway levels) is likely enroute, and those who carry on regardless while relying on deicing equipment. I am in the first group. Most "old school" pilots are in the 2nd group.

Internet weather sources have made finding the tops easier but it is still very hit and miss.

It's not a huge deal - if you have say a 20k operating ceiling. Then you can get above cloud in most non-frontal weather. For penetrating fronts, all bets are off although a 25k ceiling would appear to do it maybe 95% of the time (CBs excepted but one can presumably avoid those with radar, or visually).

[Pace]

10540

Where are the cloud tops? would be a useful piece of information. At present the only way of finding out is to ask ATC for reported cloud tops.

Icing has to be a major consideration as most airways bottom out at the worst temperature zones for icing for much of the year.

We also have the problem of having to go on oxygen to get above some weather systems, while pilots may be happy on oxygen some passengers do not like it so most trips in light GA are limited to around the 12000 foot level.

My point is that if a pilots IFR /instrument skills involve the need to be on top in the blue rather than plodding along in the murk and gloom solid IMC for the whole trip then maybe that pilot should question being there at all.

Ie you have to be able to handle hand flying with no autopilot in solid IMC and still have enough mental capacity to deal with other failures on top of that . Hence my comments of fear the worst and you maybe nicely surprised expect the best and you may be nastily surprised.

Pace

[IO540]

Where are the cloud tops? would be a useful piece of information. At present the only way of finding out is to ask ATC for reported cloud tops.I've sent you a PM. Basically most of the data comes from the GFS model e.g. NOAA (http://www.arl.noaa.gov/ready/cmet.html) (under Soundings). Various websites like Meteoblue (http://my.meteoblue.com/my/)offer variations of it.

Icing has to be a major consideration as most airways bottom out at the worst temperature zones for icing for much of the year.Exactly.

We also have the problem of having to go on oxygen to get above some weather systems, while pilots may be happy on oxygen some passengers do not like it so most trips in light GA are limited to around the 12000 foot level.TBH, a lot of people get a a headache at 12k... I would definitely have o2 up there. And if one doesn't reach VMC at 12k, what does one do? Turn back? That is not the way to do it unless de-iced and happy to hack it. One has to work ahead and climb early.

My point is that if a pilots IFR /instrument skills involve the need to be on top in the blue rather than plodding along in the murk and gloom solid IMC for the whole trip then maybe that pilot should question being there at all.No, the pilot just needs to be more clever regarding weather :) He still faces IMC during climb and descent.

Your comment would apply to airline pilots, who spend 99% in VMC.

Ie you have to be able to handle hand flying with no autopilot in solid IMC and still have enough mental capacity to deal with other failures on top of that . Hence my comments of fear the worst and you maybe nicely surprised expect the best and you may be nastily surprised.That's true. But there is still a huge practical/operational difference between hand flying in IMC for 5hrs, and doing it for 15 mins. Look at the airline pilot case again. They are not expected to fly Gatwick to Orlando in IMC, by hand. Why not? They are the elite, after all (esp. British Airways ones).

[Fright Level]

there is still a huge practical/operational difference between hand flying in IMC for 5hrs, and doing it for 15 mins. Look at the airline pilot case again. They are not expected to do that

IO540, you hit it spot on, our MEL covers flying without any of the three autopilots serviceable .. Flight crew members are limited to 5 flight hours per scheduled flight day..

Although we don't normally do it, we are expected to be able to! Climbing, descending, turbulence are all usually no problem hand flying, it's maintaining straight & level at jet cruise levels that's actually quite tricky in the thin air of the stratosphere.

PS - Thread drift - I notice there is no comment about high altitude flight (apart from the mixture restriction) in the TB20/21 POH. I would have thought operating even at FL200 would have shown very different aerodynamics. Not been above FL130 in it yet due no oxy.

[IO540]

I notice there is no comment about high altitude flight (apart from the mixture restriction) in the TB20/21 POH. I would have thought operating even at FL200 would have shown very different aerodynamics. Not been above FL130 in it yet due no oxy.

It doesn't fly any differently up there.

Obviously the IAS is lower near the ceiling, so the controls are as mushy as you would expect them to be at say 95kt IAS anywhere else. But that's all.

The TB21 goes to FL250. I am not aware of any different handling although I have never done it myself. The wing is just not very efficient in that thin air - one needs something like e.g. the Malibu.

What mixture restriction? At high levels, one needs all air one can get into the engine, so max revs (2575) and one needs the best power setting i.e. 100F ROP. No good trying to be clever with 25LOP at FL250 :)

[SNS3Guppy]

there is still a huge practical/operational difference between hand flying in IMC for 5hrs, and doing it for 15 mins. Look at the airline pilot case again. They are not expected to do that


Actually, we are. Certain phases require the use of the autopilot, such as flight in RVSM airspace, and we're even restricted as to what automation we can use; it's got to be RVSM-compliant.

What we find is that the most common habit pilots exhibit in the sim (and on the line) is that the natural first instinct is to disconnect the autopilot and hand-fly. There's more training done in management of the automation than the hand-flying, because while the automation can do wonderous things, it also complicates things somewhat...and can easily back one into a hole.

I'm the same way...my first instinct is to disconnect the autopilot and hand fly the airplane. I did so last night during an ILS approach into LAX in some heavy rain. The airplane began to pitch while coupled to the autopilot, just outside the glide slope intercept point. I noticed the glideslope indicator begin to wobble, and immediately disconnected the autopilot and hand flew the approach.

Last night we also encountered severe turbulence enroute and attempted the use of the turbulence mode, but quickly disconnected the system (despite being in RVSM) and hand flew to exit the turbulence.

Most of the guys I've flow with on the line tend to hand fly as much as possible; I normally hand fly it to about 27,000' on the way up, and hand fly the arrivals and approach where I can.

A big part of our recurrent simulator training involves hand flown emergencies, approaches, missed approaches, and engine failure profiles. We stress the ability to operate with, and without the automation. To me, the biggest challenge isn't raw-data hand flying, but using the automation.

[Pace]

No, the pilot just needs to be more clever regarding weather He still faces IMC during climb and descent.

10540

I would rephrase that to there are pilots who have to and those who choose to. Some of us do not have the luxury of selecting our flying days and 99% of the time have to accept whats thrown at us :)

Pace

[Fuji Abound]

No, the pilot just needs to be more clever regarding weather He still faces IMC during climb and descent.

10540

I would rephrase that to there are pilots who have to and those who choose to. Some of us do not have the luxury of selecting our flying days and 99% of the time have to accept whats thrown at us


Very well put. Without any intention of causing offense, it reminds me of the way cricket was played in the old days:

There were the players and the gentlemen - the players had to play because they got paid for it, the gentlemen only played if it suited them to do so. :)

[Pace]

I work as an airline pilot but on a twin turboprop flying fairly short sectors. I have flown many 6 sector day's with no autopilot, never on top of the weather (alt. limited due to 'negative 8.33). The big difference is that we have two pilots. That is what makes it as safe as it is.

C195

I would go with that comment cocerning two pilots especially in fast jets or turbprops as well as the comments by Guppy.

We too had an autopilot throw its dolly out of the pram at FL360 and to be honest hand flying at that level was not hard we did it for 100nm before sorting George out.

The jet was a straight winged Citation so I cannot comment at swept winged jets handflown in the high 30s

Pace

[IO540]

I would rephrase that to there are pilots who have to and those who choose to. Some of us do not have the luxury of selecting our flying days and 99% of the time have to accept whats thrown at us

Agree completely. But I don't see a conflict there.

Your employer needs to provide appropriate equipment. If the job is one of those which one hears about from time to time, where you either fly or are sacked, then a non-deiced TB20 would be OK maybe 80-90% of the time but will IMHO without question kill you within the year, if you did a run say Biggin to Trondheim (ENVA) every day.

One should not expect a private pilot to be able to hack the worst case possible flight, at the limits of the highest possible fuel endurance, in solid IMC, partial panel. To argue otherwise is to argue that the pilot is an idiot, departing into objectively unsuitable conditions.

The airline pilots who are supposed to fly it for 5hrs by hand are not doing it PP. They are doing it on the flight director, and the other man will be doing everything else. Also, what is the typical jet transport MEL requirement as to autopilots? I said I would not depart (in certain hard conditions) with a duff one. I don't think an airliner would either.

[Tmbstory]

Pace:

There is very little difference from your comments about straight wing Citation jet.


Tmb

[Fright Level]

What mixture restriction?

Sorry, it must be a TB21 thing, it's for engine failure above FL230 it says a power reduction with too rich a mixture may cause the engine to stop so descend below FL230 and set the throttle 1/4 open and mixture to lean and restart the engine. If that doesn't work, then into the normal engine failure checklist.

[englishal]

I was quite surprised, when practicing partial panel, as we entered actual IFR the instructor "failed" an engine in a ME aeroplane. What surprised me was that I still managed to keep the thing right way up and even kept reasonably in compliance with my IFR clearance.....This was standard instrumentation. I wasn't expecting the engine " failure" but it shows that as long as you have a TC still working then you should be ok.

The G1000 is easier to fly IFR - the horizon is huge so you quickly pickup attitude changes. The headings are accurate to a degree so it is easy to spot drifts. When in moderate turbulence it is easier to see too!

[mm_flynn]

What mixture restriction?

Sorry, it must be a TB21 thing, it's for engine failure above FL230 it says a power reduction with too rich a mixture may cause the engine to stop so descend below FL230 and set the throttle 1/4 open and mixture to lean and restart the engine. If that doesn't work, then into the normal engine failure checklist.I think it is a turbocharged thing. My Bonanza has a similar POH comment.

The way it was explained to me was - If the engine fails at high altitude you will loose boost pressure and therefore the air/fuel mixture will go way rich (only say 35% the air molecules/fuel molecule) and you will not be able to restart. So you need to lean to a mixture that will burn in the rarefied air, re-start, get boost back (wind up way way lean) and enrich back to your cruise setting.

[IO540]

Interesting, mm_flynn.

Why would the engine stop in the first place, however?

In reality, one would fly at the best MPG level which for a TB20 is ~ 10k (plus or minus 2k makes no measurable difference) and for a TB21 is - at a very rough guess since I know of hardly anybody doing this for real - around 20k.

In the absence of IMC, one would climb to these levels and ask ATC for a "stop climb" and that's it for the next few hours, generally.

However, the matter is complicated by the oxygen flow rate. At 10k this is very low and some hairy-chested pilots would happily fly for hours at 10k without it. At 20k it is pretty damn high and you've got to be careful how you breathe, and constant passenger supervision is vital, and since refills are so damn hard to get around Europe, this becomes a serious flight planning issue on long trips.

One would not fly at 23k, and probably not above ~ 16k, except for short sections to remain above clouds. Having said that, I did one 5hr flight entirely at 16k and with a 1hr bit at 19k, and all of it was stratus. No fronts at all.

I keep half an eye out for a nice TB21 since with a 25k ceiling it is objectively a more capable airways machine but can't bring myself to do it, because I would lose maybe 10% MPG (and thus range) at lower levels (including the ~ FL100 kind of level) and I know from others' experiences that finding people in the UK who can do turbocharger work can be difficult.

[mm_flynn]

Interesting, mm_flynn.

Why would the engine stop in the first place, however?

One can imagine all sorts of remote possibilities.

The most likely are the pilot...
- Runs a tank dry
- Reduces power sufficiently to loose boost pressure and the engine rich cuts.
- Leans so much that combustion stops - remember this is turbocharged so can deliver sea level power at FL250 and therefore LOP is appropriate at all levels.

Mid-teens seems to be the best compromise for me (good speed, MPG and not too much O2 issue). Have been to FL200 down to LFRS but never above that (I worry too much about the hypoxia.

[IO540]

....which could be quite tricky since the only reason one is likely to be at 23k+ is to stay above cloud (unless doing aerial pics in Nepal :) ) and if you lose the engine and have to descend you are likely to enter IMC and pick up ice, which isn't going to do a whole lot for your ability to climb back up again.... which confirms my view that a TB21 without full TKS is not worth having.

I never knew that turbo engines had these restart issues, but then I never needed to know. It has been a standard diesel issue though.