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-   -   EMS Very Slow approach - why? (https://www.pprune.org/rotorheads/504612-ems-very-slow-approach-why.html)

John R81 10th Jan 2013 11:15

Gordy

I would pull that video link if I were you. You missed him - he hid behind the truck!

SASless 10th Jan 2013 11:55

Crab,

This ain't Northern Ireland, and with very rare exceptions there are no bad guys shooting at us, and we have said the high, steep, slow approach is the better technique for avoiding wires... not the only way. In most cases using the Steep/Slow approach will allow you to see the Wires you might miss on a standard Confined Area Approach in time and avoid them. The Normal Approach you mention sounds good in theory but in reality there is a better way. That is the point being made....and most have accepted that.

In essence what you just told us is you prefer to cling to the standard night LZ approach and landing technique you learned at the Colored Pencil Academy no matter the circumstances.

Do you only wear one pair of shoes?

Gordy 10th Jan 2013 14:30

John R81


You missed him - he hid behind the truck!
We got this one though..... ;) ;) :cool: :cool:


Gomer Pylot 10th Jan 2013 14:42

Runon, sometimes they do hose down the LZ, sometimes they don't. It's hit or miss. In the area I fly, there is exactly one full-time professional fire department. The rest are volunteer, unpaid, part-timers with minimum training, doing it in their spare time to help the community, and we don't hassle them. We take what we get.

Crab, you seem to have never flown in a forested area, where the roads are lined with trees, trees are everywhere, and the power poles are mostly hidden in the trees. I recently landed in the middle of a major interstate highway for a wreck, and since the scene was near our base, we arrived before the fire department had a chance to set up an LZ and stop all the traffic, so we circled for some time while waiting. We had plenty of time to recon everything, and thought we saw a place where wires crossed the highway, but we couldn't be certain. We checked thoroughly, but couldn't see any wires. This was in broad daylight, mid-day. On final approach, we finally found the wires, the poles hidden in trees on each side of the highway, just one pair of wires in front of us. A normal fast approach would have resulted in our being in the middle of the highway with rotor blades and parts spread all over the place. You fly approaches your way over there, and I'll fly them my way here. I intend to retire alive.

500guy 10th Jan 2013 15:29

Crab.
How many wirestrikes on approach do you know of. I know of at least a quite a few. Many were fatal. How many engine failures on approach do you know of, I can think of 2 and neither was fatal. Choose your exposure.

The whole problem, and I dare say the reason we keep having these accidents is people like you that think they will be able to see wires on a full speed confined or semi-confined approach.

Watch the video again.

QTG 10th Jan 2013 15:41

Crab
If you ever leave the RAF you will learn how to fly Class 1 approaches. If you lose an engine close to the ground it may well save your life.

Runon 10th Jan 2013 19:23

That water drop getting the girls .... um "watered". Brings so many bad one liners to mind.
Cheers to you Gordy - those gave me a good laugh.

I hear you Gomer - I used to volunteer and really we weren't supposed to do anything unless we were told specifically to (you know how they are with rookies).

topendtorque 10th Jan 2013 19:24

I am surprised someone especially Sasless, hasn't supplied Runon with the real answer.

Of course they will go slow where there is a good chance of a crowd there to watch, it's when they are out in the boonies that they go real fast straight into a cloud full of rocks or whatever to make a real splash on the next days newspaper.

It is the American EMS you are asking about I presume? :ugh:

[email protected] 10th Jan 2013 20:32

So let me get this right - you guys are advocating a slow steep approach into every LS, no matter how unsuitable the floor might be for a Cat 1 engine failure after CDP landing (the slope and surface are often difficult to asses until in the hover) or how long you might spend in the H-V curve (in a single)?

Unless your LS is very small (which would necessitate a confined area approach) why not aim deeper into the LS in the knowledge that you will therefore be higher over the LS boundary (where the wires are most likely to be hidden) and are less likely to encounter tiny telephone wires (which will snap before they take out a helicopter) which are the most likely ones to surprise you.

Maybe you just don't have power lines marked on maps in countries where you operate but we do, right down to the 11KvA small lines on wooden poles (that will trap a helicopter) so for us, a decent map and a good recce, plus the abilkity to modify how we approach into the fields means we are not stuck in the - 'one size fits all and it's the only safe way to do it' slow, steep approach that seems to be the favourite of most here.

Sasless - I think I am the one advocating flexibility of thought and action - I can vary my approach to suit the conditions.

Gomer - no, we just don't have trees in UK:ugh::ugh:

500 guy

The whole problem, and I dare say the reason we keep having these accidents is people like you that think they will be able to see wires on a full speed confined or semi-confined approach.
no, people keep having these accidents because they are not looking for wires adequately - I am happy that I can do that from a low level recce and confirm it on finals without having to fly ridiculously slow and steep. My choice of exposure has kept me safe for over 30 years in some quite demanding circumstances.

SASless 10th Jan 2013 20:54

If you think every single wire shows up on a map somewhere accessible to the everyday pilot.....you are in serious need of a drug test. That statement ranks up there with something like The Sultan might say.


tiny telephone wires (which will snap before they take out a helicopter
Wrap them puppies around your P/C Links......and see what happens.


As to flying near Trees....despite there being some trees in the UK....we have wood lots bigger than some of your forests.....out west where logging still goes on.....Wires can crop up within hours.....so the valley you just flew up might not be as safe as you think on the way back home.

Single or Twin....engine failures are so far down the risk scale compared to wire strikes...particularly in degree of outcome.....they just don't matter and you know it.

As the conventional wisdom proves.....Wires can be anywhere Crab....and that means even right up there at the far end of your LZ.....that is the point Mate....one never knows.

You just keep doing your normal approaches using the school solution and allow the rest of us to do what we see as best meeting our needs.

havoc 10th Jan 2013 22:20

Germany wire strike since your talking wires
 
One dead in German helicopter crash on highway

Associated Press | Updated: January 10, 2013 23:31 IST


Berlin: A helicopter crashed on a highway in southwestern Germany on Thursday, killing the pilot, after the aircraft got caught in high-voltage power lines and exploded, police said.

Pieces of the helicopter hit a truck near the town of Schwaebisch Hall but the driver was only slightly injured. Police said they believe the pilot was alone on board.

The highway was closed in both directions following the accident, creating a major traffic jam.

German news agency DPA said the helicopter belonged to a private company in the region

Runon 11th Jan 2013 00:21

"Of course they will go slow where there is a good chance of a crowd there to watch"

LOL - HAHHAHAAA:D

spinwing 11th Jan 2013 03:52

Mmmmm ...

...... to encounter tiny telephone wires (which will snap before they take out a helicopter) ....

Crab old darling .... have you ever inspected any of those 'tiny telephone wires' close up?

During one of my 'vacations' from aviation I did in fact do a 5 year stint as a 'Telecoms tech' and spent quite some time re stringing and repairing aerial telephone lines ....

With the smallest copper aerial cable (what we call a 'one pair aerial') ... the 'tiny wires' you speak of are indeed tiny the phone conductors are a pair copper wires of 1.5mm cross sectional area and are in themselves not that strong ... BUT an aerial cable is supported by a 'catenary' wire which is made of tough steel 1/8th of an inch diameter to allow support without excessive sag between the support poles ... this IS tough stuff believe me ... if you don't strike the cable run with the appropriate 'wire protection device' on your machine before you know it, it will have wrapped itself around your pitch links or tail rotor and caused a serious loss of control before it reaches its breaking strain ... and that is just the small stuff!!

Really you don't want to go there ... and while the military tactical decision might validate such a risk ... the civilian one will not ... standard of thought should be "when there is any doubt DON'T do it".

Cheers

Devil 49 11th Jan 2013 14:42

Crab-
My employer requires the slow vertical in and a vertical out of an unimproved landing site, period. It is a compromised technique in some scenarios, but it's what I am to do.

HeliStudent 11th Jan 2013 15:40

This steep EMS approach being discussed, what kind of downward visibility does it give you of the landing site?

Gomer Pylot 11th Jan 2013 15:56

The downward visibility depends on the model, of course. If there is a chin bubble, the visibility is excellent. Without one, it's not so good. Everything is a compromise of some sort, so the approach angle and speed has to be balanced with the ability to see where you're going. The less you can see, the slower you need to be. In the model I fly, you can see almost, but not quite, vertically, up to ~70 degrees down. I don't often get completely vertical, but sometimes it's necessary for the last 50-100 feet, depending on the obstables and LZ size.

spinwing 11th Jan 2013 16:15

Mmmm ...

Remembering of course one has the option at slow(ish) speeds to put in a bit of left boot (or right as the case may be) to cock the a/c around if necessary to improve the downwards visibility ... needed perhaps with the 139, S76, B222 etc .....

HeliStudent 11th Jan 2013 16:25

Thanks for the replies. :ok:

Please forgive me if this is a very stupid question but - are wires hot? If so would it be possible to affix a small (less expensive) IR camera to the helicopter to assist in checking for wires.

If so then could there be a small flir ball beneath the aircraft that runs a pre-programmed sweep once you push a button in the cockpit and which covers the whole area beneath the helicopter and shows the pilot where the wires are?

500guy 11th Jan 2013 16:57

SASless, Spot on.

Crab, any unimproved LZ yes. same class 1 approach.

No map has 100% of wires. Telegrapgh lines will and have taken down helicopters. So have logging line and other "lines" that are temporary and would not be on your map. Powerlines are not typicaly hot, but can be under intense loads. The infrared thing would not work on denergized lines, telegraph/telephone lines, guy wires, loging lines etc. Anything that only works 95% of the time gives a false sense of security and actually detracts from safety, thats why every catalog based wire detection system or map has failed.

[email protected] 11th Jan 2013 17:28

OK, 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. There is no real excuse for hitting HT cables (but it clearly still gets done) and those are not the type of wires to be hidden in a treeline on approach to an LS.

The average height of a telephone wire in UK (at least) is about 20 feet so in order to get it wrapped around your rotor head you will have to be very low indeed (even I don't come in that low!).

I do know that copper wire is strong but the only time I know it has been a problem is when a Lynx collected about 2 KM of the stuff from a TOW missile around the MRH after flying along a valley where there had been a firing exercise. That did not bring down the helicopter and is a massive amount more than the few feet of it you are likely to collect from between telephone poles.

I can understand the imposed limitation of flying a class 1 approach from the standpoint of fare-paying passengers and air transport work - it is the legislation after all. But, if you are not employed in that sphere, it is surely better to be flexible in the style of approach - coming in steep still does not guarantee that you will see a small wire.


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