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EMS Very Slow approach - why?

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EMS Very Slow approach - why?

Old 11th Jan 2013, 18:42
  #41 (permalink)  
 
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lets pretend we are only dealing with telephone wires since anything bigger is likely to be less hidden and possibly (in a civilised country ) be marked on a map

Sorry Crab....but right there is where I quit reading. That is a false assumption upon which you attempt to build your case.

Now in addition to that....there might have to be some stipulation to whether the USA can be considered a civilized country....but that is not why your premise is at fault.


I believe B.H. Liddell Hart summed it up this way........

"The only thing harder than getting a new idea into the military mind is to get an old one out."

Last edited by SASless; 11th Jan 2013 at 18:50.
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Old 11th Jan 2013, 18:45
  #42 (permalink)  
 
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Very short wave length (I think) Radar has shown itself to useful at detecting wires....but not to the degree needed for use by Helicopters landing off airport. (Unless someone knows of something that did work.)

Also.....Wire Cutters work best with some forward speed to assist the cutter in doing its work. The key there is to hit the Wire straight or nearly straight on and fairly level.

Last edited by SASless; 11th Jan 2013 at 18:48.
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Old 11th Jan 2013, 19:08
  #43 (permalink)  
 
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WSPS, need about 35-40 knots (varies somewhat with weight of ac) to cut a 3/8" (10MM) Steel cable. In most cases WSPS only protects people who are doing things against company policy to begin with. Cruising 50-100'AGL, canyon runs etc.
The exception there would be powerline patrol, mustering, fish and game surveys, etc, military etc.

Crab, it all depends on where it his the aircraft. many of the time the wite hits the rotor, or comes right through the bubbe, others it catches the skid gear and inverts the aircraft.

The last Transmission Line Construction project I was on was built using 50kp hardware thats 50,000lb. or 22,680kg break strength. That would take down a C-130 without batting an eye.... By the way, that happend too.
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Old 11th Jan 2013, 19:09
  #44 (permalink)  
QTG
 
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Crab

Most HEMS pilots in the UK are ex-military, and therefore qualified to comment on the differences beyween civil and military aviation. HEMS approaches into genuinely restricted sites, urban areas etc, will always be conducted on the basis of risk versus need - its when the pilot earns his money, and is the reason behind the experience requirements for recruitment in the first place.

The majority of incidents, however, do not need a high risk approach, and, following a site recce, often can be accessed via a conventional approach into a small field or other suitable area close to the incident.

AssumIng this field doesn't stretch to 300 metres or so, this "conventional" approach is llkely to take the form of the "slow and steep" variety referred to. The EC135, for has 3 such "VTOL" profiles, all of which comply with Class 1 performance requirements. The same criteria can then be applied to the subsequent departure.

Yes, HEMS operations can be risky, but why make it riskier than necessary?
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Old 11th Jan 2013, 19:15
  #45 (permalink)  
 
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Crab,

Has the RAF funded attendance at the HAI Wire Strike Course for RAF Helicopter Pilots?

22,000 pilots approximately have attended that course since its inception 18 years ago.....the course gets very good reviews by the Industry overall....and Wire Strike Accidents are far fewer now than when the course began despite the vastly increased number of Operators, Aircraft, and particularly EMS/SAR operations around the World.
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Old 11th Jan 2013, 21:50
  #46 (permalink)  
 
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Sasless - no I don't think so but we have so few wirestrikes (over all UK military) that the way we train does seem to work fine. However, wires awareness is drummed into every mil helo pilot right from day one.

The argument about the wires has gone to and fro with some talking about telephone wires being difficult to spot in hedgerows and the next person talking about big HT wires. I thought we were talking about approaches into fields and other small LSs which is why I specified the telephone wires - even the yanks don't hide HT cables at 30' in treelines do they?

QTG - the question is - if you weren't constrained by the requirement to fly Class 1 approaches - would you still do it out of choice? I'm not and I don't.

Last edited by [email protected]; 11th Jan 2013 at 21:58.
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Old 11th Jan 2013, 22:20
  #47 (permalink)  
 
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Restricitions to performance such as CAT A and Class 1 approaches are not an issue in the USA. One of the problems is there is the requirement for a smooth, flat, level landing area as well as approach angles and obstacle clearance issues the prevent those profiles from being used except at Heliports, Airports, and some Heli-decks.

We are not obliged to fly that way....and generally do not.

With the prevalence of Single Engine EMS helicopters....that pretty much rules such ideas moot anyway.

I would not fly a Single Engine Helicopter at night doing EMS as I am far too old and wise to do that. I got broke in on big multi's in '68 and got to like the comfort of two engines. Had I been a Marine...I would have opted to fly the 53E as it has three engines.


As to the RAF not funding even single slot at the HAI Wire course.....that does not surprise me one single bit. After all....they do not issue coloured pencils there and the Wellington Theorem applies.

Last edited by SASless; 11th Jan 2013 at 22:23.
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Old 12th Jan 2013, 03:23
  #48 (permalink)  
 
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even the yanks don't hide HT cables at 30' in treelines do they?
Yes, they do. And as noted above, even a cable TV or telephone line stretching more than a few feet will have a steel wire supporting it, to prevent stretching and breaking. And any wire can destroy a helicopter, and has. Hit it with the skids with forward speed, even a small telephone line, and your day is done. Wrap it in the pitch change links, and your day is done. Even if you survive uninjured, the patient has no ride, and the company is out hundreds of thousands of dollars or euros. The odds of hitting a wire are orders of magnitude higher than those of an engine failure. But all said and done, you fly approaches your way, and I'll fly them mine.

Last edited by Gomer Pylot; 12th Jan 2013 at 03:31.
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Old 12th Jan 2013, 04:18
  #49 (permalink)  
 
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Would YOU see these wires if you did not see the pole..... This is one of those situations where I took off my glove and put it on the cyclic while sitting on the ground---to remind me the wires were in front before I took off. You can see them in the full size pic, but only just....:

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Old 12th Jan 2013, 08:42
  #50 (permalink)  
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The industry is not "constrained" as you put it to carry out Class 1 approaches into HEMS sites. If the option is available, however, it plainly makes sense to take the safe option rather than the "lets just go for it" technique you advocate.
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Old 12th Jan 2013, 10:43
  #51 (permalink)  
 
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I am hardly advocating a 'let's just go for it' technique but neither am I advocating a very steep and slow approach when it is not required.

Early posters seemed hard over that the only way to get into a field site safely was to make a very slow and steep (bordering on vertical) approach because that was the only way to spot wires.

I took issue with that because it isn't true - but because I mentioned NI and tactical approaches, some seem to believe I am always quickstopping into fields without a care in the world when nothing could be further from the truth.

I have done rather a lot of field landings in 30 years, day and night - (tactically, on training and on SAROPs) and have managed not to hit a wire in that time - luck? I don't think so. A decent recce backed up with a good scan on finals seems to have worked pretty well so far - sometimes the obstructions and wires do force a steep approach but when they don't I fly a normal angle and speed.

Sasless - of course you did the HAI course before you went flying - not!

How many do the US military put through that course?

The UK mil are generally not in that habit of paying other people to provide information we already know and train for.
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Old 12th Jan 2013, 12:04
  #52 (permalink)  
 
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Crab,

The RAF and British Army are also shy to listen to Lessons Learned from others when they take on well proven Aircraft and Technology too it seems.....but that is grist for another mill.

No one has impugned your reputation or skills as a helicopter pilot and no one has said you use exactly one approach to landing off airport.

Some have suggested you might have a jaundiced eye on the particular topic under discussion. These is not the first time.....and probably shall not be the last time you suffer that response.

You bring a wealth of experience and ability to the discussions....but then so do quite a few others and it is in the meeting of the minds that good information is garnered.

As folks from all over this green and blue Orb we live on....come here and contribute....suggests to me that we hear them out....discuss our different views and see if we can learn something in the process.

Just as in Religion....there is no singular path to Salvation in flying helicopters so we have to make room for different thoughts than our own. We do have to be able to politely defend our assertations and kindly accept we may not always have the only right answer.

It is a dangerous occupation we have....finding ways to make it safer is in our own best interests whoever we are, where ever we fly, and what tasks we undertake.


For good fun.....a flight up the Columbia River Gorge early in the morning while going East.....or late afternoon while going West is an interesting proposition. There are the HUGE HT Lines from the Hydro-Electric Dams, the Primary Distribution lines along the Highways on either side of the River, the Secondary Distribution lines that feed neighborhoods and factories....and theres the sneaky little bastards that feed individual houses on the tiny islands smack up against the river bank.....add in the communication lines along the railroads on either side of the River....and the wires that head up on the bluffs on either side and you have the entire mix of wires known to Man I think. Or...you can add in Mist/Fog/Rain and if you are really brave....darkness or a combination of all of that and you can have a thrill ride.

Now if you added landing to all that mix.....it really gets fun.

Sometimes they don't hide the HT lines but they do disguise the tiny ones by running them near the bigger ones so you focus on the easy to see Wires but miss the small ones.

Last edited by SASless; 12th Jan 2013 at 12:12.
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Old 12th Jan 2013, 14:00
  #53 (permalink)  
 
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Angel Wires

nothing to do with the current topic re steep/ornot approaches (pun - current/wires? Never mind!) but a reminisce about wires in general. I hung my helmet up some years ago after thirty years of mil helo flying. I was lucky on a few occasions, skilful on a few more, and got away without a wire strike. I've been pretty close on occasions, memorably once at a new South Wales hospital LS which had wires on the approach that the hospital admins and crossed headlight providing fire crews and police had failed to see. On another (rather tactical NI situation) I've been under wires that neither I nor my crew saw or had marked on our maps - it was very foggy and we were very lucky! Since retiring I have had variations on a recurring dream where I'm flying low level, usually in a city or townscape, trying to find a gap in the network of wires above me!
Wires, for helicopter pilots everywhere - they're a nightmare!

Last edited by Al-bert; 12th Jan 2013 at 14:02.
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Old 12th Jan 2013, 15:00
  #54 (permalink)  

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Since retiring I have had variations on a recurring dream where I'm flying low level, usually in a city or townscape, trying to find a gap in the network of wires above me!
Wires, for helicopter pilots everywhere - they're a nightmare!
Strewth - me too! Except I'm still flying because as the way things stand, I probably can't ever afford to retire.

My very similar nightmare is based on an episode I was involved in some thirty years ago. Over a corner of a very deep lake (one that our predecessors had successfully bombed some decades before), we found ourselves hover taxying, in freezing fog, over a set of small wires. Then, as we climbed to get over them, losing the few remaining visual references, we noticed the really big set just above us.....

I learned a lot about flying that day.

Wires / wives. Safer for a helicopter never to get mixed up with either.
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Old 12th Jan 2013, 15:10
  #55 (permalink)  
 
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Grrr Wives !

Wires / wives. Safer for a helicopter never to get mixed up with either
Too true TC, too true!!

Last edited by Al-bert; 12th Jan 2013 at 15:11.
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Old 12th Jan 2013, 15:18
  #56 (permalink)  
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Crab-
Perhaps this sentence is the nub of the misunderstanding?-

"Early posters seemed hard over that the only way to get into a field site safely was to make a very slow and steep (bordering on vertical) approach because that was the only way to spot wires."

As explained to me:
The vertical doesn't help seeing wires, the vertical descent helps you survive wires by putting the helo in the least vulnerable position possible.
The slow descent helps you see the wires and react to situations. Impatience is dangerous because it's leads to impulsive and poorly considered decisions. I have no choice but to take a minute and a half on my last 300 feet per company policy that all descents below 300' AGL will be at or less than 200 FPM. It's hard to be really good in this profession, but slow makes fine adjustments easier, and our pilots look skillful- at least me.

A fundamental principle of avoiding wires is look for the towers and poles in rights of way because wires are hard to see from altitude. Lots of issues with this, for instance the line of poles along a road will be obvious, but where the conducting wire crosses will not, it can cross at any angle, and wires are hard to see. We land on a lot of roads, I've landed on many where the wire wasn't visible except against the sky, and a few where I never saw wire even though I was looking at the hardware on the pole at both ends of the span.
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Old 12th Jan 2013, 15:36
  #57 (permalink)  
 
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I have had two out of body experiences with wires.

First one was on the far side of the Spit at Homer, Alaska in a Hughes 500D.....understand Alaska is quite large....quite sparsely populated even in the "urban" areas other than say Anchorage, Fairbanks, and a few other "Cities".

The Far Side of Homer in those days qualified as un-inhabited for all intents and purposes and after spending six months on the Aleutiian peninsula where Wires do not exist....one got quite a shock when popping over a ridge headed for the Claim Stake job....to discover the only.....like exactly the only....single phase power line strung catywampus down the ridge but smack dab across my line of flight at a height midways between the cloud deck and the tree Tops.

I saw the pole with a Transformer on my right as I popped over and down the back of the ridge.....and barely saw the pole on my left....and finally saw the wires themselves as I skimmed over them about a foot or so in mid span.

The other was while drying Cherries in Washington State. I had done the field once the day before....knew where the Pump House was and from where the Power line feeding the thing ran from. The Wire pretty much matched the line of the bigger power line further down the valley and only as I got awfully close to the near wire did it move out from where it was being hidden by the easier to see but much further away bigger set of wires. Ground speed at the time....maybe 10-12 knots....just under ETL speed. It was a darn near thing!


In a former life in a land far away....I did land a Chinook between the guy wires of a radio mast one night.....and knew nothing of it until the next morning when we were to depart. It was not an easy departure....not easy at all....as we were not only between two of the three guys....but the forward blades were under one set. The Almighty looks out for drunks and fools....being doubled blessed doesn't hurt at times.
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Old 12th Jan 2013, 20:42
  #58 (permalink)  
 
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I have had variations on a recurring dream where I'm flying low level, usually in a city or townscape, trying to find a gap in the network of wires above me!
And me.
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Old 12th Jan 2013, 20:49
  #59 (permalink)  
 
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Dreams or nightmares?

Maybe we should start a new thread? My most entertaining dream was flying a jcb (it was of course yellow) and after suffering an engine failure it was simple to 'autorotate' (except there were no rotors), bounce into a field on it's huge balloon tyres (Wessex inspired here) and exit through a convenient gate and continue by road
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Old 14th Jan 2013, 18:18
  #60 (permalink)  
 
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The HT lines normally get aircraft following roads or rivers or in limited visability. Not so much on landing, you are correct.

The Flying in the Wire Environment course that the HAI Hosts is taught by Utilities Aviation Specialists. They teach that course 50-100 times a year to operators all around the world, but primariliy in North America, Australia, and China. The US national guard has hosted the training on numerous occasions.

The army has their own training...

As a side note...We yanks have trees much taller than 30'.
Here in Oregon 300' is not at all uncommon. Douglas Firs which are about as plentiful here idiots on Just Helicopters reach about 120M.
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