Flying in snow
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My personal favourite for snow landings is to come to high hover, with escapes, and blow as much of the lose snow away.
zero speed landings are all very well, but as pointed out before you have no idea what is below the snow.
Unless there is a tactical reason for not blowing the snow I think that a high hover is a top plan. IMHO of course.
zero speed landings are all very well, but as pointed out before you have no idea what is below the snow.
Unless there is a tactical reason for not blowing the snow I think that a high hover is a top plan. IMHO of course.
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Greetings from the Great White North. Some good points brought up so far (and some REALLY bad ones), and if I may add a few, hopefully good ones, of my own......
When flying in snow.....
-Slow down.
-Beware of the fact that visual cues can be lost, even when visibility doesn't seem too bad, i.e. cloudy day when flying over lakes or vast expanses of unbroken snowcover. Approaches to snow covered areas in poor light conditions should always be made to a point or line of reference, which must be kept in sight at all times, as tiercel said in the landing / takeoff brief.
-When approaching a valley crossing or downslope in poor wx, slow down and plan your escape route/180º turn early to avoid shooting yourself into a whiteout condition. Also make sure your split-as$ed 180 doesn't take you over more unbroken white, this time at 60º of bank.
Most of this stuff is just plain common sense.
Accumulation is a different thing, and let's not confuse snow with ice. The RFM will provide restrictions regarding flight in moisture / snow and may offer relief when certain kits are installed (i.e. snow baffles / deflectors, relights, etc). Also, many operators in snowy climes develop and certify their own kits for their particular needs. When operating in these environments, it is imperative that the aircraft be properly equipped, as Randy G said.
Wet snow can accumulate on the fuselage, but in reality, the visibilities associated with heavy wet snow are usually so poor that prolonged flight is not an option anyway. If the vis is not reduced such as to slow you down, there likely won't be much in the way of accumulation. This build-up does not in any way affect the rotor or tail rotor, but may pose a problem for unprotected intakes, unheated pitot static systems etc.
Colder (< approx -5º) snow poses little threat in most PROPERLY EQUIPPED aircraft during reasonable flight conditions (vis > ½ mile), that meaning having the appropriate snow deflectors or what have you for that type. Again, there may be an RFM restriction or specified minimum vis.
Another thing to be careful of when working in a cold environment is the ability of blowing snow to infest every cavity in the aircraft. If the helicopter has been left outside for a prolonged period of SBS, you may find the tailboom, transmission deck, or engine bay full of hard packed snow. This can not only cause problems when it melts (and refreezes), but may also have C/G implications.
I add my hat to the ring of supporters of the high hover approach and slow, planned, visual departures. As the previous post said, avoid the 'zero-zero' thing unless you REALLY know what your doing, OR, if you're on fire, getting shot at or making movies....
[This message has been edited by CTD (edited 06 March 2001).]
When flying in snow.....
-Slow down.
-Beware of the fact that visual cues can be lost, even when visibility doesn't seem too bad, i.e. cloudy day when flying over lakes or vast expanses of unbroken snowcover. Approaches to snow covered areas in poor light conditions should always be made to a point or line of reference, which must be kept in sight at all times, as tiercel said in the landing / takeoff brief.
-When approaching a valley crossing or downslope in poor wx, slow down and plan your escape route/180º turn early to avoid shooting yourself into a whiteout condition. Also make sure your split-as$ed 180 doesn't take you over more unbroken white, this time at 60º of bank.
Most of this stuff is just plain common sense.
Accumulation is a different thing, and let's not confuse snow with ice. The RFM will provide restrictions regarding flight in moisture / snow and may offer relief when certain kits are installed (i.e. snow baffles / deflectors, relights, etc). Also, many operators in snowy climes develop and certify their own kits for their particular needs. When operating in these environments, it is imperative that the aircraft be properly equipped, as Randy G said.
Wet snow can accumulate on the fuselage, but in reality, the visibilities associated with heavy wet snow are usually so poor that prolonged flight is not an option anyway. If the vis is not reduced such as to slow you down, there likely won't be much in the way of accumulation. This build-up does not in any way affect the rotor or tail rotor, but may pose a problem for unprotected intakes, unheated pitot static systems etc.
Colder (< approx -5º) snow poses little threat in most PROPERLY EQUIPPED aircraft during reasonable flight conditions (vis > ½ mile), that meaning having the appropriate snow deflectors or what have you for that type. Again, there may be an RFM restriction or specified minimum vis.
Another thing to be careful of when working in a cold environment is the ability of blowing snow to infest every cavity in the aircraft. If the helicopter has been left outside for a prolonged period of SBS, you may find the tailboom, transmission deck, or engine bay full of hard packed snow. This can not only cause problems when it melts (and refreezes), but may also have C/G implications.
I add my hat to the ring of supporters of the high hover approach and slow, planned, visual departures. As the previous post said, avoid the 'zero-zero' thing unless you REALLY know what your doing, OR, if you're on fire, getting shot at or making movies....
[This message has been edited by CTD (edited 06 March 2001).]
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If sticky wet snow or precip has melted then refrozen on your blades you have a problem,but the normal hoar frost/light icing associated with overnight parking outside on both main and tail rotors will burn off rapidly at 100% Nr and some pitch is pulled.
I've had to do that on medium Bells where it takes 100% torque to hover with a less than maximum load initially but after a few seconds, performance improves remarkably as the ice burns off.Sounds crazy,I know, but as long as there is no imbalance all blades will clean very rapidly.
Picking up ice in flight is different, especially on the tail rotor which,from my experience, often sheds ice unevenly causing imbalance and serious vibration.Picking up ice in flight on the main blades can appear to have little effect, but the buildup is usually on the slower sections of the blade and affects the autorotative sections.To be avoided obviously,especially in single engined machines.
Aside from the ice building up on rotors,the sheer weight of ice on the fuselage can be surprisingly high.
I've had to do that on medium Bells where it takes 100% torque to hover with a less than maximum load initially but after a few seconds, performance improves remarkably as the ice burns off.Sounds crazy,I know, but as long as there is no imbalance all blades will clean very rapidly.
Picking up ice in flight is different, especially on the tail rotor which,from my experience, often sheds ice unevenly causing imbalance and serious vibration.Picking up ice in flight on the main blades can appear to have little effect, but the buildup is usually on the slower sections of the blade and affects the autorotative sections.To be avoided obviously,especially in single engined machines.
Aside from the ice building up on rotors,the sheer weight of ice on the fuselage can be surprisingly high.
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I may be able to answer that (from a Canadian perspective at least, I'm not sure where Tiercel operated his).
I seem to remember it as a flight manual restriction, because I think I can still recall the temporary pages in the book. If memory serves, it resulted from an accident on the James Bay hydro development (around 1980?) where a 500 flamed out in falling snow and crashed. The investigation revealed the Auto Relight, which was located on the lower console between the passenger's feet was not turned on. The investigators also concluded that the Auto Relight could not be seen by the pilot if the center seat was occupied, and therefore the pilot could easily miss it if it were not on. The result was the restriction.
As a solution to the problem, most Canadian operators then relocated the Auto Relight to the outside of the instrument panel on the copilot's side, where the pilot could see it. If your 500 already had this or an equivalent mod applied, there would be no restriction. I think Tiecel may have his dates a little off, by the early eighties this would have already been done, I believe.
I haven't flown a 500 for 8 years, but that's how I remember it. Hope it sheds some light.
I seem to remember it as a flight manual restriction, because I think I can still recall the temporary pages in the book. If memory serves, it resulted from an accident on the James Bay hydro development (around 1980?) where a 500 flamed out in falling snow and crashed. The investigation revealed the Auto Relight, which was located on the lower console between the passenger's feet was not turned on. The investigators also concluded that the Auto Relight could not be seen by the pilot if the center seat was occupied, and therefore the pilot could easily miss it if it were not on. The result was the restriction.
As a solution to the problem, most Canadian operators then relocated the Auto Relight to the outside of the instrument panel on the copilot's side, where the pilot could see it. If your 500 already had this or an equivalent mod applied, there would be no restriction. I think Tiecel may have his dates a little off, by the early eighties this would have already been done, I believe.
I haven't flown a 500 for 8 years, but that's how I remember it. Hope it sheds some light.
Guest
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Tiercel: well where did you crawl from under?
You are quite correct in spotting my mistake regarding flight below +5 degrees in visible moisture,,,blah blah. It should have been 0 degrees. Sincere apologies to all for this.
Regarding the rest:
Last month a 6800hr russian ex mil EMS pilot killed himself doing a high hover approach to land. He cleared the lose snow from about 50' then descended and whilst doing so, shifted some more - lost vis references and struck the deck with a MRB. Good advice tiercel!
Engines overtemping whilst taking off: If the skids stick to the deck and you pull power to overcome the problem, depending on your a/c type and the amount of overcontrolling certain pilots may inflict on the controls one is in danger of overtorquing leading to an overtemp (it's happened, I've seen it) - dimbo...what other overtemp is there apart from me reading your drivel!
I learned my snow flying in Nova Scotia/Newfoundland and the Rockies military style...I suspect you've been reading about it or worse still teaching it without any quality experience....
I'm concerned that a newbie to the rotorhead forum feels that he has to respond with such venom. A shame really, I was beginning to appreciate this particular forum because of its more relaxed position on matters. Perhaps you've jumped across from another more agressive forum like: wannabees....!
By all means question my contribution but blatant slagging only serves to dilute the purpose of this thread.
Go and have a drink on me.....with ice
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Thermal runaway.
You are quite correct in spotting my mistake regarding flight below +5 degrees in visible moisture,,,blah blah. It should have been 0 degrees. Sincere apologies to all for this.
Regarding the rest:
Last month a 6800hr russian ex mil EMS pilot killed himself doing a high hover approach to land. He cleared the lose snow from about 50' then descended and whilst doing so, shifted some more - lost vis references and struck the deck with a MRB. Good advice tiercel!
Engines overtemping whilst taking off: If the skids stick to the deck and you pull power to overcome the problem, depending on your a/c type and the amount of overcontrolling certain pilots may inflict on the controls one is in danger of overtorquing leading to an overtemp (it's happened, I've seen it) - dimbo...what other overtemp is there apart from me reading your drivel!
I learned my snow flying in Nova Scotia/Newfoundland and the Rockies military style...I suspect you've been reading about it or worse still teaching it without any quality experience....
I'm concerned that a newbie to the rotorhead forum feels that he has to respond with such venom. A shame really, I was beginning to appreciate this particular forum because of its more relaxed position on matters. Perhaps you've jumped across from another more agressive forum like: wannabees....!
By all means question my contribution but blatant slagging only serves to dilute the purpose of this thread.
Go and have a drink on me.....with ice
------------------
Thermal runaway.
Guest
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Pac Rotors yes CHC does operate an advanced/mountain school in Penticton, B.C. Be a great place to go and learn some good techniques on flying in/around snow. Good skiing around there too. 
There are arguments (for/against) for either technique high hover vs no hover. Some in heli-skiing use the no hover landing with great success. While myself and others have not had any problems with an approach to a hover to wait for the snow to clear.
I recommend cleaning all contaminants off of any critical surface before you start up. Unless you really know your a/c, you may not know when the contamination is gone. I won't gamble with peoples lives. It may be a pain in the butt to brush the snow/frost off the rotors, but it sure beats any of the alternatives. If you operate in an area where frost/snow is a problem, then use covers. They prevent rotors from developing frost, and snow won't freeze to the blades.
You can see the blade covers on this 206, we also covered up the engine area and used an electric heater to keet the engine warm. Using the blade covers, I never had to clean frost off the blades.
Cheers
Randy_G
If you can't stand the heat ...
Then turn up the airconditioning !!
p.s. talk about irony, here I am downunda in the Land of Aus giving tips on flying in the snow. In case any of you don't think I know anything about winter flying, I have flown all over western Canada, and in the Cdn Arctic in the winter.
There are arguments (for/against) for either technique high hover vs no hover. Some in heli-skiing use the no hover landing with great success. While myself and others have not had any problems with an approach to a hover to wait for the snow to clear.
I recommend cleaning all contaminants off of any critical surface before you start up. Unless you really know your a/c, you may not know when the contamination is gone. I won't gamble with peoples lives. It may be a pain in the butt to brush the snow/frost off the rotors, but it sure beats any of the alternatives. If you operate in an area where frost/snow is a problem, then use covers. They prevent rotors from developing frost, and snow won't freeze to the blades.
You can see the blade covers on this 206, we also covered up the engine area and used an electric heater to keet the engine warm. Using the blade covers, I never had to clean frost off the blades.
Cheers
Randy_G
If you can't stand the heat ...
Then turn up the airconditioning !!
p.s. talk about irony, here I am downunda in the Land of Aus giving tips on flying in the snow.
In case any of you don't think I know anything about winter flying, I have flown all over western Canada, and in the Cdn Arctic in the winter.
Guest
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One further piece of advice. Despite all the problems your aircraft may have, the loss of visual cues close to the ground is what kills most people in these conditions, both during take-off and landing.
As well as external whiteout, beware of misting-up of the transparencies before and during take-off. Try to keep the doors open as long as possible while you are getting strapped in and started up, especially if you have been working hard to sweep off all that snow, free the skids etc. This will make sure any perspiration, heavy breathing etc (!) goes outside.
If you do get canopy misting make very sure you don't lift off until it is cleared; the last thing you want is your own self-induced IMC hover. Keep a soft cloth available to wipe the screen and use the screen demist if you have it.
In colder climates where the OAT gets lower than about minus five or so, canopy misting is likely to be less of a problem as the air is drier. Use of screen heat (or any inside heat) may not then be be a good idea as it may put snow contacting the airframe back into the sticky range causing build-up on the outside. Also, if you are carrying pax with snow on their clothing (skiers, soldiers, whatever) you don't want it to melt as it will make them wet which doesn't help them once they go back outside into the cold.
As always, get some instruction from someone who is used to the local conditions!
As well as external whiteout, beware of misting-up of the transparencies before and during take-off. Try to keep the doors open as long as possible while you are getting strapped in and started up, especially if you have been working hard to sweep off all that snow, free the skids etc. This will make sure any perspiration, heavy breathing etc (!) goes outside.
If you do get canopy misting make very sure you don't lift off until it is cleared; the last thing you want is your own self-induced IMC hover. Keep a soft cloth available to wipe the screen and use the screen demist if you have it.
In colder climates where the OAT gets lower than about minus five or so, canopy misting is likely to be less of a problem as the air is drier. Use of screen heat (or any inside heat) may not then be be a good idea as it may put snow contacting the airframe back into the sticky range causing build-up on the outside. Also, if you are carrying pax with snow on their clothing (skiers, soldiers, whatever) you don't want it to melt as it will make them wet which doesn't help them once they go back outside into the cold.
As always, get some instruction from someone who is used to the local conditions!
Guest
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TC...I read my original post again, the one which seems to have offended you, then I read your reply and I stick by my original statement....."if you don't know what you're talking about......". I still don't get the overtemp though, seems to me the last thing you'd want to do if you were "stuck" in a helicopter would be to pull full power. Ever hear of dynamic rollover?
Randy G brings up a good point that some of the heli-ski pilots use the no-hover ldg technique, and I use it from time to time as well. To clarify my response to hoverbover's question for the benefit of Randy and others, these heliski guys are very high time mountain pilots, with heaps of experience flying in winter conditions. The person asking for advice in this forum has very little winter experience, and my response was tailored to that level.
BTW Thomas, to answer your off-handed comment about my lack of experience and having read about some of these things..... I'm a mid-time (just under 8K) ATPL who has spent most of his time in Western, Eastern and Arctic Canada, among other hot spots. And no, I do not currently share my lack of 'quality experience' with others on a professional basis.
Randy G brings up a good point that some of the heli-ski pilots use the no-hover ldg technique, and I use it from time to time as well. To clarify my response to hoverbover's question for the benefit of Randy and others, these heliski guys are very high time mountain pilots, with heaps of experience flying in winter conditions. The person asking for advice in this forum has very little winter experience, and my response was tailored to that level.
BTW Thomas, to answer your off-handed comment about my lack of experience and having read about some of these things..... I'm a mid-time (just under 8K) ATPL who has spent most of his time in Western, Eastern and Arctic Canada, among other hot spots. And no, I do not currently share my lack of 'quality experience' with others on a professional basis.
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Thomas stick to your guns, Tiercel, you are in error. I for one have flown in 1 type where engine anti-icing was required below +10 deg C and another that required engine anti-icing at +3 deg (in visibility <1000m due to moisture) both due to the temp drop in the engine intakes. Granted there are types which do not suffer as much, it is a product of the design of the air intake and such extras as FOD guards. (Remember P1 V1 T1 / P2 V2 T2 from your ATPL?)
Personally, I favour the zero/zero (no hover landing) technique and at least 1 reference. While I was doing supply trips in the antartic, if there was no suitable reference I used to use fire a flare (smoke if poss) into the snow, it gave me a reference and a good wind cue, very good if you are making an approach in a bowl where the surface wind could be 180 different from the 500' wind. (Why do chaps always want their stuff dropped halfway up a mountain in a bowl?)
BTW, 173mm icing in one sortie!!! look at http://www.gkn-whl.co.uk/eh101news/e...rrent/hot.html
Personally, I favour the zero/zero (no hover landing) technique and at least 1 reference. While I was doing supply trips in the antartic, if there was no suitable reference I used to use fire a flare (smoke if poss) into the snow, it gave me a reference and a good wind cue, very good if you are making an approach in a bowl where the surface wind could be 180 different from the 500' wind. (Why do chaps always want their stuff dropped halfway up a mountain in a bowl?)
BTW, 173mm icing in one sortie!!! look at http://www.gkn-whl.co.uk/eh101news/e...rrent/hot.html
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To all
2 Days 31 Posts and counting,excellent info from everyone,keep it coming.
To TC and Tiercel
Please don't start fighting, you both have more experience than I will ever have, don't fall out over this pleeeeease!
Thanks to one and all,keep the info coming !!!!
regards
hoverbover
PS
One thought I have had, are the blades warmer(friction) or colder (wind chill) than OAT,when flying ?
2 Days 31 Posts and counting,excellent info from everyone,keep it coming.
To TC and Tiercel
Please don't start fighting, you both have more experience than I will ever have, don't fall out over this pleeeeease!
Thanks to one and all,keep the info coming !!!!
regards
hoverbover
PS
One thought I have had, are the blades warmer(friction) or colder (wind chill) than OAT,when flying ?
Guest
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Grey Area! Whooaaa laddie! You are correct in what you say, but read again.....I didn't for one second say that ANTI ICE wasn't required below anything...what the man said was "Do not fly in visible moisture below 0 degrees, is good karma for MOST civvy pilots. Due to the venturi effect at the engine intakes (Po) this drops further causing freezing and the engines could cut out!" That is what I responded to, the "do not fly". Anti ice is different, true.
As I said in my last post, I use the no hover technique as well, but wouldn't recommend it until one becomes very comfortable with the other aspects of winter flying, which hoverbover by his own admission appears not to have achieved yet.
HoverB, Blades will be warmer due to friction.
As I said in my last post, I use the no hover technique as well, but wouldn't recommend it until one becomes very comfortable with the other aspects of winter flying, which hoverbover by his own admission appears not to have achieved yet.
HoverB, Blades will be warmer due to friction.
Guest
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hover boy, wind chill only effects fleshy things like you and I.....
as far as the high hover versus zero zero, wouldn't it be better to lose visual reference (if inevitable) at ground level than in a high hover? how can you tell just how high that blowing snow will go?
as far as the high hover versus zero zero, wouldn't it be better to lose visual reference (if inevitable) at ground level than in a high hover? how can you tell just how high that blowing snow will go?
Guest
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Hover Bover...During flight operations the blades cannot physically get any colder than ambient, they will be slightly warmer due to friction. This will vary by type, tip speed and temperature.
‘Wind chill’ occurs when an object is cooled below ambient by the heat lost during the evaporation process, or ‘latent heat of vaporization’. So, unless the blades were sweating, they can’t be subject to wind chill!
Imlanphere: Not necessarily....to lose visual reference near ground level may not leave time to recover if you have a high closure rate, as you likely would in a no hover landing situation. Not good anywhere of course!
The high hover vs. no hover could be debated for ever. I use both up here in the Great White Wasteland, depending on the situation or loading. Both have their issues, and both must be used with caution and finess.
In the high hover method, the letdown must be smooth, slow and controlled, ALWAYS maintaining reference. This precludes its use when very heavy for some helicopters. The no hover method requires a precision approach, faith in what lies below, and a zero speed touchdown while staying ahead of your downwash. Not too bad in a 25 kt wind, but it can get very sporty on a calm day.
I personally believe it requires more skill and experience on the part of the pilot, and have to agree that it should be avoided, or at least practiced in a controlled environment, by folks who aren't winter current.
Thomas Coupling, I flew in all those places too. When were you in Newfoundland? Who were you with? From there?
[This message has been edited by CTD (edited 07 March 2001).]
‘Wind chill’ occurs when an object is cooled below ambient by the heat lost during the evaporation process, or ‘latent heat of vaporization’. So, unless the blades were sweating, they can’t be subject to wind chill!
Imlanphere: Not necessarily....to lose visual reference near ground level may not leave time to recover if you have a high closure rate, as you likely would in a no hover landing situation. Not good anywhere of course!
The high hover vs. no hover could be debated for ever. I use both up here in the Great White Wasteland, depending on the situation or loading. Both have their issues, and both must be used with caution and finess.
In the high hover method, the letdown must be smooth, slow and controlled, ALWAYS maintaining reference. This precludes its use when very heavy for some helicopters. The no hover method requires a precision approach, faith in what lies below, and a zero speed touchdown while staying ahead of your downwash. Not too bad in a 25 kt wind, but it can get very sporty on a calm day.
I personally believe it requires more skill and experience on the part of the pilot, and have to agree that it should be avoided, or at least practiced in a controlled environment, by folks who aren't winter current.
Thomas Coupling, I flew in all those places too. When were you in Newfoundland? Who were you with? From there?
[This message has been edited by CTD (edited 07 March 2001).]
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To Hover Bover:
The only time snow is really a problem for take-off or landing is when it is newly fallen. After it has been on the ground for 3 or 4 days it usually doesn’t blow around much.
I prefer the techniques mentioned by Tiercel and CTD. When you arrive in a high hover ( 30 to 50 feet depending on snow and down-wash of aircraft) it takes a bit of patience to wait for the snow to clear , make sure you have good references when you're waiting. If its windy , with a lot of snow on the ground your reference for landing is sort of straight down out the side window; I would recommend practicing some landings using side window references for practice. You have to be sharp to do the no hover technique and it is certainly no something that I would use going into a night helipad.
There is one point that no one has mentioned and that is , after landing in deep snow you usually “pound it down ” i.e. pump the collective up and down until the skids reach the ground or the aircraft belly is resting on the snow. This prevents the gear from braking through the crust unexpectedly with the aircraft at ground idle. ( Canadian operators use bear paws on the back of the skids to keep the tail rotor clear .)
With regards to over-temping, I can’t comment on all aircraft but I know that if any aircraft that I’ve flown in the winter were to over-temp , I would bet that it couldn’t pass a power assurance check..
PS. Spend a winter season flying in Canada and all the snow mysteries will become clear.
IHL
[This message has been edited by IHL (edited 08 March 2001).]
The only time snow is really a problem for take-off or landing is when it is newly fallen. After it has been on the ground for 3 or 4 days it usually doesn’t blow around much.
I prefer the techniques mentioned by Tiercel and CTD. When you arrive in a high hover ( 30 to 50 feet depending on snow and down-wash of aircraft) it takes a bit of patience to wait for the snow to clear , make sure you have good references when you're waiting. If its windy , with a lot of snow on the ground your reference for landing is sort of straight down out the side window; I would recommend practicing some landings using side window references for practice. You have to be sharp to do the no hover technique and it is certainly no something that I would use going into a night helipad.
There is one point that no one has mentioned and that is , after landing in deep snow you usually “pound it down ” i.e. pump the collective up and down until the skids reach the ground or the aircraft belly is resting on the snow. This prevents the gear from braking through the crust unexpectedly with the aircraft at ground idle. ( Canadian operators use bear paws on the back of the skids to keep the tail rotor clear .)
With regards to over-temping, I can’t comment on all aircraft but I know that if any aircraft that I’ve flown in the winter were to over-temp , I would bet that it couldn’t pass a power assurance check..
PS. Spend a winter season flying in Canada and all the snow mysteries will become clear.
IHL
[This message has been edited by IHL (edited 08 March 2001).]
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There will always be disagreement and discussion among pilots about approach and landing techniques for snow,as well as mountain technique.Having read with interest all in this post I thought I'd add a bit more for the benefit of those seeking information.The experienced people on this forum have their own ideas and are unlikely to modify them much now.There is one thing here that hasn't really been mentioned and thats to use a method with which you are comfortable.
When I first went Heliskiing I was forced to do approaches in a way that my instructor and boss swore was the "Correct way".It may have been to him,but I was more comfortable using a different[more flexible]technique that I developed over time and I believe I was safer doing what I was comfortable with than operating an obviously legitimate way but made me uneasy.In my opinion,listen to all the suggestions in here,but be comfortable with whatever you adopt.
I have been taught both flat and steep approach to landing technique and several methods of landing in snow.All of them have their good and bad points so I usually adapted a technique dependant on the conditions at the time,ie knowing how to use any technique and knowing which one would be safest.Most of the time I didn't have the luxury of being able to enter a high hover due to weight and altitude,so no hover was the only option.So,for those of you wanting info,learn all the techniques because you may not have the option of choosing the one you want.
Having re-read one of my posts I would like to clarify one thing.My remark about burning off hoar frost by hovering applies in conditions of no precipitation.ie the aircraft sitting outside on a cold clear night.It burns off frost evenly and quickly,I've never had an imbalance.If somehow there is contaminate on the blades that affects lift you'll notice it with a power check and there'll be loss of lift and vibration.This remark was made more in the context of discussion between experienced people and I was unwise to suggest it be adopted by newcomers to winter flying.An intimate familiarity with the aircraft is essential and would probably only be felt by someone operating an aircraft professionally on a daily basis.Having said that,to remove/melt frozen precip off rotors is time consuming and must be meticulously done to avoid imbalance between the blades or else you'll have serious vibrations that will not go away.
When I first went Heliskiing I was forced to do approaches in a way that my instructor and boss swore was the "Correct way".It may have been to him,but I was more comfortable using a different[more flexible]technique that I developed over time and I believe I was safer doing what I was comfortable with than operating an obviously legitimate way but made me uneasy.In my opinion,listen to all the suggestions in here,but be comfortable with whatever you adopt.
I have been taught both flat and steep approach to landing technique and several methods of landing in snow.All of them have their good and bad points so I usually adapted a technique dependant on the conditions at the time,ie knowing how to use any technique and knowing which one would be safest.Most of the time I didn't have the luxury of being able to enter a high hover due to weight and altitude,so no hover was the only option.So,for those of you wanting info,learn all the techniques because you may not have the option of choosing the one you want.
Having re-read one of my posts I would like to clarify one thing.My remark about burning off hoar frost by hovering applies in conditions of no precipitation.ie the aircraft sitting outside on a cold clear night.It burns off frost evenly and quickly,I've never had an imbalance.If somehow there is contaminate on the blades that affects lift you'll notice it with a power check and there'll be loss of lift and vibration.This remark was made more in the context of discussion between experienced people and I was unwise to suggest it be adopted by newcomers to winter flying.An intimate familiarity with the aircraft is essential and would probably only be felt by someone operating an aircraft professionally on a daily basis.Having said that,to remove/melt frozen precip off rotors is time consuming and must be meticulously done to avoid imbalance between the blades or else you'll have serious vibrations that will not go away.
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Addition to ShyTorque's good pointers on misting...... if it gets reeeeeeeeal cold, the problem becomes frosting. Even though the air is dry, the surface temperature of the windows can be -30 or -40º. The moisture from all those heavy breathing pax sticks hard, and at those temperatures, without windshield heat, can take forever to get rid of. As ShyQ says, leave the doors open (Brrrr), or start before loading pax and run the heater/defrost.