CFIT
Join Date: Jan 2001
Location: In the boot of my car!
Posts: 5,982
Likes: 0
Received 0 Likes
on
0 Posts
errm, and have just entered cloud inadvertantly amongst hills below MSA.
Aircraft had no weather radar. Decided looking at the sat images that flying low level along loch ness to clear the weather to the west was my better option then turning and flying over the isles past the IOM and to WAL.
Initially stayed over the loch at 1000 ft agl. but lowering cloud and visibility made me change my mind and climb above the MSA with a rough ride but knowing I would clear weather to the west.
With due respect pilots do get into situations for one reason or other to think otherwise is not realistic or are comments made by fair weather flyers.
The clip that started this thread showed a huge mistake which could have been a disaster. Its all very well to say pilots shouldnt do this or that but they do and I thought that is what we were talking about.
Pace
Join Date: Oct 2007
Location: England
Posts: 102
Likes: 0
Received 0 Likes
on
0 Posts
Agree - people can and do end up in these predicaments - my take was: how realistic is for such to have then demonstrate excellent IR skills and good situational awareness when the moment before they went inadvertant IMC in the hills below MSA. And quite possibly having a bad judgement day on so many levels prior to that!
Numptie to sky-god in a flash, just like expected to recover an inadvertant spin
(btw going IMC was never in the plan, or part of a plan B, is my assumption wrt inadvertant IMC).
Numptie to sky-god in a flash, just like expected to recover an inadvertant spin
(btw going IMC was never in the plan, or part of a plan B, is my assumption wrt inadvertant IMC).
Join Date: Nov 2008
Location: Suffolk
Posts: 117
Likes: 0
Received 0 Likes
on
0 Posts
C172 pitot has a large position error at low speeds.
DO.
DO.
. Not only are the static and dynamic pressure instruments at risk of increased error in unusual attitudes and at the extremes of their performance range but the observation by the pilot is constrained by the need to safely fly the aircraft while making the observations. I had a yoke mounted Garmin GPS 96 running during the flight. I have downloaded the information it recorded to provide a check of the observations while flying the stall and mushing down and have put some graphs of the data on Facebook at: http://www.facebook.com/album.php?aid=2025023&id=1118091118&l=b2b72910ccI used Garmin MapSource to display the track and profile of the route I flew. From this I was able to identify one of the stalls in the data set. I copied just the data for the stall and clime out into a Microsoft Excel spreadsheet to graph out the height against time. This was to allow me identify a section of the stalled descent that is clearly where the aircraft is mushing down so I could get a measurement of the rate it was descending.
The measurement section I chose starts at 16:05:17 with the aircraft at 3467 feet and finishes at 16:06:23 with the aircraft at 2705 feet. The rate of decent was therefore 693 feet per minute. A simple linear regression line through the data shows it to be a stable descent along a straight line since the R-squared is 0.94. Which I interpret to mean that only about 6% of the variation in this data was due to a deviation from the linear trend line.
Before 16:05:17 my interpretation of the graph is that the aircraft is losing lift and entering the stall mushing. The section in the descent after 16:06:23 is likely to be where stall recovery has been initiated and the aircraft is being reconfigured to clime out.
The ground speed variation during the descent was not stable as can be seen from the very low R-squared value. It is likely that this is simply reflecting the prevailing wind conditions. I carried out the stall into wind over a reservoir in Essex just south of Colchester on the 25th Oct. The weather at the time was clear but windy. A nearby local private automated weather station in Colchester reports reading 270 degrees 5 to 10 Knots at the time of the flight http://www.jbest.net/weather/weatherSearch.aspx?fd=25%2f10%2f2009
I have included graphs of the landing and roll out at the end of the flight to provide a basis for a rough comparison for this aircraft between the descent rate and ground speed for the stalled configuration and a conventional landing. Since the aircraft was flown down final with 30 degrees of flap at 65 Knots indicated air speed the ground speed shows a head wind was present of around 10 Knots.
Climbing IMC in Valleys
There a number of Canadian approaches where the missed approach requires a shuttle climb, i.e. a climb in a hold.
The hold is of course based upon a holding fix or two which allows you to use your ADF, VOR, DME or GPS to stay well clear of the rocks.
With some of these airports you have to use the missed approach to leave in IMC.
The entire approach is flight tested in VFR to ensure correct signal reception.
Having looked at approach design criteria, it scares me to hear people advocating tight spiral climbs. 15 kt. of wind and several circles later where are you going to be
The hold is of course based upon a holding fix or two which allows you to use your ADF, VOR, DME or GPS to stay well clear of the rocks.
With some of these airports you have to use the missed approach to leave in IMC.
The entire approach is flight tested in VFR to ensure correct signal reception.
Having looked at approach design criteria, it scares me to hear people advocating tight spiral climbs. 15 kt. of wind and several circles later where are you going to be
Join Date: Jan 2001
Location: In the boot of my car!
Posts: 5,982
Likes: 0
Received 0 Likes
on
0 Posts
Having looked at approach design criteria, it scares me to hear people advocating tight spiral climbs. 15 kt. of wind and several circles later where are you going to be
To be in solid cloud for whatever reason unsure of position surrounded by hills or mountains would be very scary.
So what would you do in that situation if a tight spiral climb scares you so much? would you climb straight ahead hoping you can out climb the mountains? would you make a 180 remembering you still have to make a turn where the hill slopes put you closer? or would you cross everything and hope there was no bang? solution please.
Yes I have flown IFR departures where a spiral climb is required to 10000 feet before setting course. Doesnt that hint at something to you??
Pace
Join Date: Jun 2003
Location: EuroGA.org
Posts: 13,787
Likes: 0
Received 0 Likes
on
0 Posts
Having looked at approach design criteria, it scares me to hear people advocating tight spiral climbs. 15 kt. of wind and several circles later where are you going to be
Without a GPS, you should not be in IMC anyway (21st century)
Join Date: Oct 2003
Location: UK
Posts: 510
Likes: 0
Received 0 Likes
on
0 Posts
Pace,
Very true. But we know getting into those situations is wrong and preventable.
If you were to be presented with your Inverness scenario again, what would you do, same again or something else?
With due respect pilots do get into situations for one reason or other to think otherwise is not realistic or are comments made by fair weather flyers.
If you were to be presented with your Inverness scenario again, what would you do, same again or something else?
Join Date: Jan 2001
Location: In the boot of my car!
Posts: 5,982
Likes: 0
Received 0 Likes
on
0 Posts
If you were to be presented with your Inverness scenario again, what would you do, same again or something else?
exactly the same as it was the correct call for the conditions. IFR airways in the freezing level with all the embedded CBs and NO radar was not an option.
That left IFR below airways batting through CBs but not in the freezing level or VFR along loch ness towards clear weather to the west.
The option there was was to take plan B and fly IFR below CAS which was what I took when VFR was no longer safely possible.
I was always taught never do anything in flying without an out as that becomes a game of russian roulette and that I never play.
The difference was I knew exactly where I was but still spiralled up before setting course.
10540 talks of GPS ? all well and good if you have a unit with terrain etc. Not so good with a King 90B or even worse!
there are those who have to fly (within reason) and those who dont.
I am afraid that with all the armchair pilot discussions pilots do get into a mess real world and unsure of position, in cloud surrounded by hills/ mountains.
A tight spiral climb would be my option. Other pilots can do what they want thats their choice.
Pace
Join Date: Aug 2009
Location: In a country
Posts: 183
Likes: 0
Received 0 Likes
on
0 Posts
Some people on here obviously not actually operated SEP in big mountains, all this talk of hammerheads and tight spiral climbs etc etc.
If you fly in a big mountain environment you do not enter solid IMC ever when VFR, and who ever said they maybe head down writing when it happens has no clue. You spend all your time flying tight up against the side of the valley wall checking behind you and down other valleys as they pass to make sure you can turn around before entering this crap. It is so important to check the weather is not blowing in behind you and cutting off your exit, no head down at any time apart from a quick glance at the instruments.
It worries me that so many people are chatting about what they think they would do if they got into IMC in the mts instead what they would do to never get into IMC in the mts. You can fly under solid overcast with a good level of safety, but you must must must keep your escape route available at all times. I spent a couple of years in the Southern Alps of NZ flying commercially, average height of the peaks is probably around 9000ft complete with weather coming up from Antarctica!
If you fly in a big mountain environment you do not enter solid IMC ever when VFR, and who ever said they maybe head down writing when it happens has no clue. You spend all your time flying tight up against the side of the valley wall checking behind you and down other valleys as they pass to make sure you can turn around before entering this crap. It is so important to check the weather is not blowing in behind you and cutting off your exit, no head down at any time apart from a quick glance at the instruments.
It worries me that so many people are chatting about what they think they would do if they got into IMC in the mts instead what they would do to never get into IMC in the mts. You can fly under solid overcast with a good level of safety, but you must must must keep your escape route available at all times. I spent a couple of years in the Southern Alps of NZ flying commercially, average height of the peaks is probably around 9000ft complete with weather coming up from Antarctica!
Join Date: Oct 2003
Location: UK
Posts: 510
Likes: 0
Received 0 Likes
on
0 Posts
Just a thought (whilst i was walking the dog in the pouring rain). Allow me to put my commercial pilot's hat on for a moment.
If I were to be doing a passenger flight and ended up in having to or indeed inadvertently (whatever that means) go IMC below MSA, I could be disciplined. I would have been in direct contravention of the JAR (or whatever they call themselves this month) compliant Company Ops manual. The CAA could potentially have a case for pulling my employers AOC.
In other words, I have to make sure I remain VMC at all times below MSA (except of course when making an instrument approach or in case of emergency). I think I would have a hard case to prove that going IMC in a valley was an emergency. In short I have to be able to go VFR and stay VFR or go IFR the whole way or not go at all.
This of course is a private flyers forum, and I don't think that private flyers have such strict rules for this case. Except of course the rules for entering the Darwin awards.
If I were to be doing a passenger flight and ended up in having to or indeed inadvertently (whatever that means) go IMC below MSA, I could be disciplined. I would have been in direct contravention of the JAR (or whatever they call themselves this month) compliant Company Ops manual. The CAA could potentially have a case for pulling my employers AOC.
In other words, I have to make sure I remain VMC at all times below MSA (except of course when making an instrument approach or in case of emergency). I think I would have a hard case to prove that going IMC in a valley was an emergency. In short I have to be able to go VFR and stay VFR or go IFR the whole way or not go at all.
This of course is a private flyers forum, and I don't think that private flyers have such strict rules for this case. Except of course the rules for entering the Darwin awards.
Join Date: Jun 2003
Location: EuroGA.org
Posts: 13,787
Likes: 0
Received 0 Likes
on
0 Posts
Droopystop - I agree.
However, the kind of commercial operation which you may be half thinking of does this all the time... scud running at 400ft all the way across the Channel
Of course the pilot is the cream of the CAA cream, a class 1 medical every 6 months, etc. and no autopilot because fitting one would cost a fortune and real pilots don't need one
I am not suprised that, without pressurisation etc, these flights operate only over the water and not from say the south east to N Wales. Operating over any terrain, their despatch % would be pretty poor.
However, the kind of commercial operation which you may be half thinking of does this all the time... scud running at 400ft all the way across the Channel
Of course the pilot is the cream of the CAA cream, a class 1 medical every 6 months, etc. and no autopilot because fitting one would cost a fortune and real pilots don't need one
I am not suprised that, without pressurisation etc, these flights operate only over the water and not from say the south east to N Wales. Operating over any terrain, their despatch % would be pretty poor.
Join Date: Jan 2001
Location: In the boot of my car!
Posts: 5,982
Likes: 0
Received 0 Likes
on
0 Posts
I just wondered if a night in Inverness would have been a better option for a ppl?
My last post on this. Firstly I am an ATP and have thousands of hours in multi piston aircraft in all weather, all over Scotland in summer winter day and Night. I am also a Captain on Citation Jets.
Go back to the beginning of the thread and read what started it.
It was an aircraft clip flying in cloud which hit bushes on a hill side.
The thread is not about avoiding the situation it was about what to do if someone ever gets in a situation IN cloud unsure of position surrounded by hills.
I have made a suggestion which was to keep the aircraft as close to one spot as possible until enough hight had been aquired to get clearance over the terrain.
I hope you never get in that situation or anyone else as it is a dire situation to be in with no 100% safe options.
Mumble as much as you want but please offer some alternatives to what we were talking about as I would love to know what you would do????
Pace
Join Date: May 2001
Location: 75N 16E
Age: 54
Posts: 4,729
Likes: 0
Received 0 Likes
on
0 Posts
In other words, I have to make sure I remain VMC at all times below MSA (except of course when making an instrument approach or in case of emergency).
Join Date: Oct 2003
Location: UK
Posts: 510
Likes: 0
Received 0 Likes
on
0 Posts
Pace,
Sorry, I didn't think this was getting personal.
What would I do? Never ever go IMC in a valley. That is my point. There is, as you say, no 100% assured way out. Therefore you make absolutely sure you don't go in. To try to pretend there is general plan for getting out of such a situation is folly (and not a little frightening coming from an ATPL). An escape plan has to be time, place and type specific and may not work. If there is something to learn from this thread, its don't go there in first place.
If we are going to play top trumps, I have 1000 hours SAR experience in Scotland, plus thousands of heavy twin rotary time, almost all IFR at or below 3000'.
AL,
SIDs don't count - they are afterall designed to get you from the ground to MSA in whatever the weather, and I am sure the case you mention ensures terrain separation.
IO540,
I wasn't really thinking of any sort of operator other than thinking what I have to comply with. I have no experience of fixedwing ops manuals, but I am pretty certain that IMC below MSA is a no no (JAR OPS requirement) and VFR weather conditions are well defined. If the customer only hires a VFR plane, then he gets what he pays for and if the weather is not VFR, then captain has to say no and the customer has to live with that. I guess I am very lucky working for a company that respects a captain's decision not to go on the grounds of safety. In fact we are expected to cancel a flight if it's not safe or not legal. If that isn't the case elsewhere, then the CAA isn't doing it's job of protecting the passengers.
Sorry, I didn't think this was getting personal.
What would I do? Never ever go IMC in a valley. That is my point. There is, as you say, no 100% assured way out. Therefore you make absolutely sure you don't go in. To try to pretend there is general plan for getting out of such a situation is folly (and not a little frightening coming from an ATPL). An escape plan has to be time, place and type specific and may not work. If there is something to learn from this thread, its don't go there in first place.
If we are going to play top trumps, I have 1000 hours SAR experience in Scotland, plus thousands of heavy twin rotary time, almost all IFR at or below 3000'.
AL,
SIDs don't count - they are afterall designed to get you from the ground to MSA in whatever the weather, and I am sure the case you mention ensures terrain separation.
IO540,
I wasn't really thinking of any sort of operator other than thinking what I have to comply with. I have no experience of fixedwing ops manuals, but I am pretty certain that IMC below MSA is a no no (JAR OPS requirement) and VFR weather conditions are well defined. If the customer only hires a VFR plane, then he gets what he pays for and if the weather is not VFR, then captain has to say no and the customer has to live with that. I guess I am very lucky working for a company that respects a captain's decision not to go on the grounds of safety. In fact we are expected to cancel a flight if it's not safe or not legal. If that isn't the case elsewhere, then the CAA isn't doing it's job of protecting the passengers.
Join Date: Jan 2001
Location: In the boot of my car!
Posts: 5,982
Likes: 0
Received 0 Likes
on
0 Posts
If we are going to play top trumps, I have 1000 hours SAR experience in Scotland, plus thousands of heavy twin rotary time, almost all IFR at or below 3000'.
No not playing top trumps. Yes I totally agree with you that avoiding that situation has to be no 1 priority.
Having said that we have to be realistic and realise that there are hundreds of lives that have been lost in aviation because a pilot has done something he should not have done or has got into a situation he should not be in.
I still hold that if anyone is stupid enough to find themselves lost and in cloud below hills/mountains for whatever reason then unless they are flying a fighter jet which they can point skywards and go up like a rocket their best way out is to contain the aircraft as close to one spot and climb to a safe altitude.
Whether thats in a holding pattern or spiral (I would go for a spiral with slightly increased bank until above the MSA.
What are the alternatives? climb in any direction with your legs crossed?
Avoid YES but sadly we have to be realistic to peoples failings too. As we know most accidents are pilot ERROR and it would be great if they were taught to and avoided those errors but they dont.
Pace
Join Date: Jan 2002
Location: Aberdeen
Posts: 1,234
Likes: 0
Received 0 Likes
on
0 Posts
The discussion is interesting but perhaps I can bring it back toward the private flying arena?
99% of private pilots do not have an instrument qualification - so promising as a climb to MSA appears it is simply not a viable option fofr the vast majority of private pilots.
From my point of view (1000 hrs of VFR flying which I have paid for!) climbing - be it along a glen or in a sprial is unlikely to have a high potential of success. My aircraft is not a great instrument platform - if it were a C172 or cherrytree then it wouldd make more sense - but it still leaves a transit off some 50 miles and then a descent - potentially all IMC, possibly with ice and certainly with turbulence.
So my options are a 'canyon turn' or if the route behind me has closed, a forced landing. The latter is a last resort to avoid the IMC option.
99% of private pilots do not have an instrument qualification - so promising as a climb to MSA appears it is simply not a viable option fofr the vast majority of private pilots.
From my point of view (1000 hrs of VFR flying which I have paid for!) climbing - be it along a glen or in a sprial is unlikely to have a high potential of success. My aircraft is not a great instrument platform - if it were a C172 or cherrytree then it wouldd make more sense - but it still leaves a transit off some 50 miles and then a descent - potentially all IMC, possibly with ice and certainly with turbulence.
So my options are a 'canyon turn' or if the route behind me has closed, a forced landing. The latter is a last resort to avoid the IMC option.
Join Date: Sep 2003
Location: 59°45'36N 10°27'59E
Posts: 1,032
Likes: 0
Received 0 Likes
on
0 Posts
Was it 178 seconds they quoted some years ago regarding the time the average VFR only pilot had before disorientation set in after entry into IMC?
Myself, I will be doing the same as gasax, but I have no intention of having to do so in the first place! *knock on wood*
Myself, I will be doing the same as gasax, but I have no intention of having to do so in the first place! *knock on wood*
Join Date: Jun 2003
Location: EuroGA.org
Posts: 13,787
Likes: 0
Received 0 Likes
on
0 Posts
99% of private pilots do not have an instrument qualification - so promising as a climb to MSA appears it is simply not a viable option fofr the vast majority of private pilots.
(the early attrition rate in GA is massive and as a result most of those flying have been at it for yonks) I think that a lot more than 1% have at some stage held the IMCR. How many I can't guess (5% to 20% maybe) and most will be lapsed but that doesn't mean they cannot hold a plane the right way up. Also, the training sufficient to do the most basic instrument flight doesn't take long - far far less than getting the IMCR.
Was it 178 seconds they quoted some years ago regarding the time the average VFR only pilot had before disorientation set in after entry into IMC?
Obviously I agree one should not do IMC if not instrument flight capable, but I do think it takes far less to do it and get away with it (the alternative being death, basically) in order to get out of IMC, than most would think.