Wire strike protection?

[alwynhartman]

How effective is a wire strike protection installation when a helicopter flies into a power line or telephone line at speed?

What are the general limitations of such systems eg, max wire thickness?

Does anyone perhaps have photos of a helicopter that survived such an incident?

Im actually looking for photos of helicopters that have had WSPS installed, and then had an incident where the system worked as intended.

The pix on those two links and most of the ones I can find appears to relate to accidents without WSPS.

Thanks for any help!

[Jet Ranger]

HELAS system (on EC-135) can detect, I think, 5mm thick wire on 1.5 km distance, LASER system.
It costs 700.000 EUR.

[GoodGrief]

It's called HELLAS. German border police has it.
Apparently 50 units in operation world wide.
Go to 34:00 in this report. Seems to be working nicely.

Die fliegenden Hightech-Cops - Die Reportage XXL - N24.de (http://www.n24.de/news/newsitem_7076664.html?id=1191778&autoplay=true)

[Gordy]

This was a friend of mine:

Linky thing to PDF of "Lessons Learned" (http://amd.nbc.gov/safety/library/LessonsLearned/FY2011/IALL1105.pdf)

[heloguy412]

Try this link.

http://www.bristol.ca/Downloads/WSPS%20four%20page%20PDF.pdfI have seen firsthand how well the system works. Up to 3 wires the size of your thumb is the reported ability.

Cheers

[Shell Management]

This is excellent equipment that should be standard fit.

[heloguy412]

So tell me why wire strike protection isn't on all helos?

http://farm8.staticflickr.com/7195/6886203065_16570f4c38_z.jpg

[handysnaks]

Because we don't all wazz around at low level!

[before landing check list]

You stay airborne forever? Of course you low level, at least 2X/flight.

[handysnaks]

That is correct but I do try to take-off and land in non-wazz mode!:p

[170']

It's a good question but complicated answer,

Mostly additional weight and expense if you question honest management. (if you can find any)

They are a good proposition in certain applications, for an example where you have pilots flying somewhat standard tasks such as charter in flatlands, corporate/VIP where you're not landing anywhere very challenging but might land in a yard where someone just installed a SWER since last time you were there, and forgot to mention it etc :ugh:

But: Many transmission conductors are too large to cut (18-29mm) steel reinforced (most small gage are aluminum) and we don't have the mass or speed for the cutter to work correctly.

Landing in moraines or toe-ins to steep terrain etc, the bottom cutter can be a real danger. (I swapped ships one time back in the early 90's and forgot it had the cutters installed and nearly flipped the 212 over when it caught on a rock sticking out of moraine debris). We then removed the bottom cutter blade, but our PMI (principle maintenance inspector) said the STC was all or nothing, so we pulled the system out...

Personally I don't like them for utility ops, where logic would suggest they're most needed. But I can see the merits for other types of work...

Naturally, if I'd survived a wire strike because of a WSPS I might feel differently...

170

[SilsoeSid]

So tell me why wire strike protection isn't on all helos?


Safety Study of Wire Strike Devices Installed on Civil and Military Helicopters
http://www.tc.faa.gov/its/worldpac/techrpt/ar0825.pdf

Summary of the findings of the wire strike warning and protection systems:

•The WSPS is most effective when the helicopter impacts the wires nearly perpendicular to the wires in a level attitude and at flight speeds of more than 30 knots.

•The WSPS is available for about 25% of the helicopters.


Page 25, Table 8. Helicopters Involved in Wire StrikesThus, nearly 74% of the helicopters involved in the wire strikes could not have been fitted with wire cutters.

[206 jock]

Can I be really shallow and say that I had a set fitted on my 206 because they look really cool:ok:

Shall I get my own coat or does someone want to fetch it for me?

[g-mady]

Im with you - Half of everything is looks! :rolleyes:

[Manchester]

Eddie1 - may we have your source data for "Wires are one of the main reasons for fatal accidents in helicopters" please?

[EN48]

Put WSPS on my 407 because my insurance company thought was a good idea (even though I dont fly in a wire environment). Not so much in love with the looks.

[mickjoebill]

The bottom one can get in the way of nose mounted cameras.


Mickjoebill

[TRC]

The bottom one can get in the way of nose mounted cameras

The outboard 4 feet of the main rotor blades sometimes get in shot using a side mount too - maybe we should get them all shortened.

I can think of quite a few nose mounts that avoid the lower cutter, but maybe you brief your pilots to fly under the wires so the top cutter can get them.

[Gordy]

They are good for catching birds too.....I got this one at night back in 97:

http://i76.photobucket.com/albums/j35/helokat/Strike-1.jpg

http://i76.photobucket.com/albums/j35/helokat/scan0009.jpg

[mickjoebill]

I can think of quite a few nose mounts that avoid the lower cutter
Whilst the single pole brackets can be fitted the cutter can get into shot and is compromised because the camera sits well in front of it.

Incorporating a cutter into nose mount hard point (the so called sharks fin on AS 350 single pole mounts) would be a help, because the area between camera pole and nose of the chopper is a natural trap for wires that slide down the windscreen.


Any stats on the number of occurrences, without wire strike kit of where the wire bites, is it mast or skids/crosstubes?


Mickjoebill

[TRC]

Any stats on the number of occurrences, without wire strike kit of where the wire bites, is it mast or skids?

Two instances spring to mind that affected me quite closely - in your line of business too....

An Alouette II, wire strike - three wires. One around the mast and rotating controls, the second through the cabin - you can guess the outcome and the third hit the skid posts.

A 350 with a side mount, hit a single wire with the forward crosstube - went under the camera operator's feet by inches - would have taken his legs off if they had been flying a foot lower.

It's quite arbitrary which part of the helicopter is hit by the wires.

The answer is a good recce before you fly the shot.

[mickjoebill]

Sept 8th, Quebec, looks like he/she turned to miss the pylon and the main cut the wire.
Watch the slo mo to see wire hit the ground.

Hélicoptère à St-Tite - YouTube


mickjoebill

[DSquadron]

The Closest call we've had here in recent times was a Gaz on a night sortie, while on the day recce, A set of power lines was observed and noted. unfortunately there was two sets of power lines and the P1 and P2 "noted" each one of the two lines. on the night sortie the lines were seen at the last minute and evasive action was taken. The power line struck the FWD upright section of the Stb Skid three inches below the top of the skid, if it had been three inches higher the line would of passed over that into the skid support between fuselage and skid, causing a much nastier end to this story. the line snapped and left a large arc burn on the skid and blacked out the surrounding area that night. That was two very luck pilots.