A question for helicopter S & R crews

[Compass Call]

When watching Hollywoods finest rescuing sailors from submarines, the heli crew always drop an 'earth' wire to the sub first. Apparently this is to ensure that the sub and heli are both at the same electrical potential before lowering a crewman. It seems that if this is not done the crewman completes a circuit and gets frazzled.

Is this just Hollywood making the movie interesting? Or do both the heli and sub have to be earthed together before a crewman can be lowered?

May I also add "Well Done" to those SAR crews involved in the HMCS Chicoutimi rescue. :ok:

CC

[adr]

I am not a wokka bloke, but I do know that it is (or was) SOP for MRTs to allow a winch line to touch the ground before touching it.

And I endorse the praise.

adr

[The Swinging Monkey]

CC

No, its not a 'hollywood ism' it IS fact.
If you don't earth first, chances are you and/or the survivor will get a nasty 'hello' in the form a an electrical zap, when they make contact with each other.

My congrats also for all involved in the Sub rescue - well done all.

Kind regards
The Swinging Monkey

[extpwron]

I think you might be talking about the “High Line” – see picture below.

http://news.bbc.co.uk/1/hi/uk/3723124.stm

The winch wire is in the Winchman’s hand. Just below his hand is the winch hook attached to which is the nylon ‘high-line’ which you can just see looping down to the guy at the front end of the tower. This speeds up returning the hook and strops for multiple lifts and can often prevent swings developing during transfers.

There may well be a metal static discharge wire (about 6-8 feet in length) attached to the hook but that would be out of picture.

[Cornish Jack]

Neither Hollywood 'hype' nor absolutely necessary. As long as you don't touch the wire with your hand as you contact boat, ship or land, the static discharges down the outside of your immersion suit ... unless you are still externally very wet. However, I did, once, get a real eye-watering belt touching down on a Marine Craft pinnace ... between my tooth fillings!! :{ It took some time for the sort of ozone residue to clear the tonsils.
In the mid 60's RAE Farnborough did some trials with us to measure the charge levels we were dealing with - this was on Whirlwinds. They took their gear on the marine craft and used a volt/ammeter in series with an earthing 'prod' to check us each time we came on board. From memory, the figures were something like 175,000 plus volts but very little ampereage. That was the maximum on the initial touch down but it built up quite quickly again. Happy days:D

[Oggin Aviator]

I am not a SAR chap however as a rotary backseater we are trained in SAR procedures just in case. Therefore not an expert - we leave this to 771, 22, 202 and 203(R), and a great job they do to :ok:

We actually use a metal static discharge wire as mentioned by extpwron, commonly known as a "zap lead". 8 to 10' long, it clags on to the end of the winch wire and should, theoretically, touch the ground, sea or fixed object such as a deck before the winchman does, thus grounding the static build up.

If you see one coming down at you DONT reach out and grab it :eek:

[teeteringhead]

Same principle as earthing the hook when picking up an underslung load (usl).

Remember doing usl training with RMAS at STANTA a while ago. Trainee Rupert hooker had been given earthing probe ... standing smartly at attention with probe in one hand .... and earth spike in the other!! Oh how we laughed when it worked as advertised:rolleyes:

[ShyTorque]

My intro to helis was a holding pilot at B flight RAF Leconfield, then equipped with Whirlwinds. The crews hadn't been able to do much recent training due to recent bad weather so they used me as a professional survivor for a few weeks.

One drizzly evening I was winched down to the Bridlington lifeboat. A certain large MALM used a double strop technique to get us both down to the deck, with my legs dangling lower than his. As I touched the deck, I suffered an almighty static jolt, which caused both my knees to convulse upwards, right into said winchman's wedding tackle. He didn't speak to me much for a while.... or anyone else for that matter. :ooh:

[fatobs]

Oggin Aviator..
Don't forget Gannet SAR flight in your list "SAR experts" only the busiest SAR unit in the UK last year and on track for the honours again this year.

If the rest of the Navy don't know about us no wonder the media always refer to us as "Crabs" (at least they got last weeks job correct)

In regard to "zap leads" they don't work on subs / MCMV's due to the anachoic tiles / plastic boat preventing the static being dischraged. Flying guide states that you should not use a ZAP lead when operating to these vessels. there should be an earthing team on deck to earth the wire as you descend..... just make sure the fools do not earth you instead of the wire!!

[WE Branch Fanatic]

Aren't Gannet Flight part of 771?

[fatobs]

WE Branch Fanatic

NO !!!!!!!!!!!!!!!!!

Gannet SAR Flight is a stand alone unit and is not associated with 77 NAS.

Culdrose is our parent air station but that is as far as it goes.

Good to see the rest of the Navy is so well informed.

Oh Well only 2 years left.

[Oggin Aviator]

Fat Obs

Apologies - I also thought Gannet SAR was a part of 771. All these changes - I dont know !!!!!

Your handle and location makes me think - wasnt I on the HWI course with you, the Jungly and the Kiwi? If so you may realise why I am so ill informed as to the parenting situation.

Keep up the good work.

Oggin

[Crashondeck]

While you are on the subject, what about the 4 Coastguard SAR units.......?

[Phil Tofull]

The static charge built up by a large helo like a Sea King can be substantial - think of it as a large van de Graaf generator. I've known a winchman's orange suit split from ankle to shoulder where the charge tracked, despite using a 'zapper snapper' :}

I also saw a fellow pilot on SKTU earth the SACRU hook with the ground plate from the earthing probe still in his flying suit pocket:O

[Wideeyedboyinthedark]

Obviously Oggin Aviator has spent too much time abroad and is missing the FAA! Fatobs is absolutely correct - Gannet SAR are not parented by 771 Sqn They are a Stand Alone unit running their own Flight and Establishment. (Check that out SARF boys!) :eek:

For those who are interested :ugh: Gannet SAR Flight were formerly established in 2001 when 819 NAS were disbanded. As the pingers left so HMS GANNET drew down, the phoenix that rose out of the ashes was Gannet SAR Flight (:D) Presumably Defence Cuts and political spin doctoring is behind the fact that they haven't been given a Sqn/Flt Number :ooh:

Operating 2 Aircraft and recently converted to NVG, they are very busy and as Fatobs implied, are in amongst the bigboys on a regular basis. :ok:

Presumably one benefit of running your own base is you get to arrange your social calendar to suit as well. I know that they comandeered an old 747 parked near their dispersal, whereupon they whipped half the seats out and adopted it as their dinning room for their Taranto night celebration Dinner - complete with a giant FLY NAVY Banner painted on the outside :ok: :E Cracking Show!

For the spotters why not check out their Web Pages within the Navy site:sad: It gives an update of their recent SAR jobs.
http://www.rnjobs.co.uk/static/pages/2873.html

[Oggin Aviator]

Obviously Oggin Aviator has spent too much time abroad

Yeah but the LOA helps a lot ! Missing the FAA - mmmm, undecided on that one :E

Is it that obvious and do I know you - you obviously know who I am ??!! Can you ask Fat Obs to PM me to say hi.

All the best to all the SAR units in the UK (and worldwide), you all do a marvellous job, sometimes in very trying circumstances :ok:

[bigdipper]

Fat Obs.................

A question for fat obs as it appears you are at gannet?
With regards to the sub rescue a few questions have arisen after crewroom discussions of late!

What was the thinking behind the lifting of an unconcious or certainly not really with it cas by the use of a single strop? The footage shows the strop to be back to front with the cas chin down(airway?), surely the use of double stropping whilst lifting the cas with a winchman would have helped? It appeared from the footage that a winchman was not on the fin at the time which may explain why the strop was fitted incorrectly!

What would the press have made from a cas falling from a strop during this rescue? It would be interesting to know your SOP's on the above????

[fatobs]

Big Dipper,

For the record the film footage was of the first two casualties being lifted, they were both fully concious and in no danger. There was no comms to fully brief the submariners so unable to brief them on Hi-line technique etc. (they ditched the first 2) There was no aircrewman on the boat at that time due to the adverse weather.

The last casualty who was unconcious and therefore cannot be lifted using a single lift technique, the aircrewman was finally lowered to the boat and the casualty recovered IAW SOP's using a hypothermic lift.

A little knowledge can be a bad thing, don't always believe what you see / read in the media.

Oggin aviator

Affirm, as I always said a Bagger with a winch is as dangerous as a sailor with a gun.

[Jigsaw]

Fat Obs

Good to see you are still pushing for promotion by promoting your unit in the face of Royal Naval indifference!

Ps what do you know about winching anyway....heard that you weren't too good at it!

[Oggin Aviator]

as I always said a Bagger with a winch is as dangerous as a sailor with a gun .....
... or as a Pinger with any sort of blunt instrument :}

[WE Branch Fanatic]

Good job the Merlin is so good then!

I found this website on Gannet Flight (http://www.royal-marines.mod.uk/static/pages/2865.html)

Also SAR missions are performed by shipborne helicopters (as a secondary function) - including ones carried by RFAs.