I think there are a couple of points that need highlighting.
TRIGGERED LIGHTENING: NEW SCIENCE Although we knew some time ago that helicopters get hit by lightening, resulting in AAIB and CAA reports, it was only during 2012 and 2013 that academic work was published that allowed an understanding of the mechanism of these events and prediction of high risk. :8 Until recently, no mountain rescue training had ever been cancelled due to risk levels for triggered lightening. Last month at Kintail, a mountain rescue first aid training day with hillside scenarios had to do without helicopter support because of the risk level for triggered lightening. :ugh: HELICOPTER TRAINING: BRISTOW INVERNESS Lossiemouth has always served the busiest Scottish MRT. This was where the action was. You may have recently heard the radio interview with John Prince during which he described how he had wanted a posting to Lossiemouth for that very reason. :ok: Bristow Inverness inherits that mantle. Unfortunately, it does so with both the AW189 problem and the storm damage problem. This has resulted in serious delays. Initial training for MRT and others, during January, was cancelled and several other such training events have also been cancelled since. :{ While teams in the west with S-92 experience have taken a step back, some of those in the east, like Cairngorm, have still failed to get the training that they require. It appears that a number of factors have conspired to cause that problem. Undoubtedly, one of those is vital aircrew training that has similarly fallen behind the planned advance. From where I sit, it is better that they catch up with their NVIS training but for Cairngorm, having much of the team still never having trained with a modern helicopter three weeks into service provision and in the fourth month since the start of the work-up period, must be extremely frustrating. |
Not very often that I pipe up but I think it is warranted on this occasion.
Back in December on a rotation through Sumburgh I was grounded for two days while trying to get guys offshore. Why? Triggered lightning and a lot of red bands of it. Did the SAR guys I was sharing an office fly? Of course they did. Ok they weren't training due to TL but they were quick enough getting themselves out the door when the klaxon went off to provide top cover to a few fishing vessels that were struggling near Orkney. Quite interesting to hear also that a precautionary landing was conducted for 10 minutes when St Elmo decided to distribute his fire over parts of the aircraft. Good call in my eyes. LZ |
Hot LZ, as you state, TL is an issue overwater and Sumburgh is in the middle of plenty of that so their decision is quite understood and eminently valid.
However, the polar maritime air flow that gives the potential conditions for TL relies on the airmass being unstable with respect to sea temperature which, last weekend at least, was higher than the inland temperatures. So, even if the wind was in the right direction to affect Inverness itself, it is extremely unlikely that the conditions for TL would be found even a short way inland because the land temperatures were too low to sustain the instability of the airmass. Aberdeen is vulnerable - as proven - but cancelling mountain training on the basis of an extremely remote chance??? |
Aberdeen is vulnerable - as proven - but cancelling mountain training on the basis of an extremely remote chance??? Flash; Bang; Cer-ching.......... Woops You can't just ignore a forecast. Perhaps you did in your previous life just for shi-s and giggles. |
Triggered lightning is nothing to do with overwater or not. It can occur when mixed-phase precipitation occurs (ie rain + hail or snow) which obviously tends to occur around zero centigrade. This is because the two phases have different densities and hence buoyancies and hence vertical speeds. The speed differential creates friction and static charge. Around zero C the electric field strength is maximised and the ionisation caused by engines and/or rotor blade static discharge can create a conductive path.
It only seems to be overwater because offshore IFR helicopters spend most of their time offshore, and often close to zero C in winter. There has never been a triggered strike in the summer (May to Oct -ish) Strikes are costly but have always been extant. The current met office modelling system unfortunately has no accounting for false positive warnings - it's a self-fulfilling prophesy that it shows a warning and no one flys so no one gets struck. Personally I don't think it works very well and obviously from the met office's point of view it is better to have a false warning than a lack of warning. Taken to extreme of course if it gave a permanent warning no-one would ever get struck. OK it's not as bad as that but it is crude. However I think Bristow is perhaps being a bit foolish in citing this reason for not doing the training, even though I'm sure we all accept that it would fly on a real shout. And playing the "safety" card is BS. It's about the cost. No-one has ever been injured from a triggered lightning strike, although one lot did get wet socks many moons ago with inadequately certified tail rotor blades. Anyway, don't SAR boys all get vertigo above 200'AGL? It seems highly unlikely that a triggered strike could occur at low level. Too much irrational corporate risk-averseness I'm sorry to say, and too many managers who don't actually understand the science. |
CRAB
Check out the Met Office work on this. Investigating and predicting helicopter-triggered lightning strikes - Met Office Theire example map clearly shows overland hot-spots. http://www.metoffice.gov.uk/media/im...n_radar_L2.jpg After our cancellation due to triggered lightning risk I have had a look at work on this phenomenon and hope to get someone to do a piece on the subject for the Scottish Mountain Rescue magazine at some stage. HELICOMPARATOR Vertigo above 200'AGL? Wouldn't surprise me! However, whereas a Sea King has always tended to be flown through the glens, in an S-92 there is more of a tendency for folk to just fly across the top. The science is still new. I would hope that in 5 years time there will be a finer honed forecast. |
Triggered lightning is nothing to do with overwater or not. It can occur when mixed-phase precipitation occurs (ie rain + hail or snow) which obviously tends to occur around zero centigrade. This is because the two phases have different densities and hence buoyancies and hence vertical speeds. The speed differential creates friction and static charge. Around zero C the electric field strength is maximised and the ionisation caused by engines and/or rotor blade static discharge can create a conductive path. The met office and caa pages highlight that overland there is usually sufficient electrical potential to trigger a lightning strike without needing a helicopter to initiate it whereas, over the sea, the cloud can be charged but not sufficiently to discharge cloud to cloud or cloud to ground - that is when the helo comes along with a vastly different electrical polarity and triggers the strike. Jim, that radar picture shows showers both over sea and overland and rain rate - nothing new there - the fact that a helicopter suffered a lightning strike in the bounded box ( note that it is over the sea) does not mean that every shower gives the same risk. |
Investigation and prediction of helicopter-triggered lightning over the North Sea - Wilkinson - 2012 - Meteorological Applications - Wiley Online Library
All you need to know about TL - strangely no mention whatsoever about overland............ The opening line Helicopter-triggered lightning is a phenomenon which affects operations over the North Sea during the winter. |
strangely no mention whatsoever about overland............ |
Well yes Crab. You have a point. One that fits with my scenario of the SK flying through the glens. And where we may be at present is "We have a S-92, we can fly anywhere. Oops, no we can't."
It looks to me like we need more science done. (Not going to hold my breath.) In relation to the recent Kintail Ex, like all NW teams we are often using an aircraft that flies 20 minutes over the Minch to get here so over water flight is part of the overall scenario. |
Originally Posted by [email protected]
(Post 8958553)
Yet SAR helicopters have been operating in the mountains in, around and below the zero degree isotherm in mixed precipitation for many years but there are no reports of triggered lightning.
The met office and caa pages highlight that overland there is usually sufficient electrical potential to trigger a lightning strike without needing a helicopter to initiate it whereas, over the sea, the cloud can be charged but not sufficiently to discharge cloud to cloud or cloud to ground - that is when the helo comes along with a vastly different electrical polarity and triggers the strike. I also think that a low flying helicopter is less likely to be a trigger because if there is that much electric field strength near the ground, an air to ground strike is likely to happen anyway. But I think for a heli flying at say 3000' agl the probabilities are much the same onshore as offshore. Yes there is a throwaway line about "usually" onshore, but I don't see any science behind that view. Personally I think it was a mistake to decline training because of this risk, since there would inevitably be a publicity backlash, however I was in the Cairngorms on Sunday afternoon and there was one massive snowstorm all afternoon which closed the Lecht and the A96 and that for me would have been good enough reason to stay cosy in Ops unless I really had to go flying! |
Probably because it was commissioned to look at operations over the North Sea.....but, you knew that. As HC points out, the weather was crap anyway so that would have been a far better justification. |
...because that was where the phenomenon was reported Well firstly, if you look at the number of offshore oil support flights / hours per year, and then the number of triggered lightning strikes - around 1 or 2 a year on average IIRC, and then look at the number of onshore mil SAR flights / hours per year, you will see than on probability alone it is not surprising that there has not been a mil SAR triggered lightning strike |
New SAR base at Lydd is under construction.
Building under way for new Lydd SAR facilities - BBC News mmitch. |
All leaves Humberside looking very isolated up the East Coast.
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Oh - that went down with a fizz and sigh.......
I'll ask again because people may not know that allegedly Bristow are refusing inland SAR @ night if it requires NVD's. True or False? And are they also refusing future EMS contam transport in open cockpit helicopters? := |
That can't be true TC, I have been told so often here that the new Service will be so much better and that all I have been doing is scaremongering about operational capability:ugh:
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Might be totally unrelated but does anyone know why Bristows EC225 G-ZZSJ has been performing deck winching and wet winching out of Dyce?
http://i61.tinypic.com/2mgtbpk.jpg http://i62.tinypic.com/k1uexx.jpg http://i61.tinypic.com/wjcqi1.jpg |
Practising Public Transport winching. It is quite normal to winch transfer personnel to and from tankers and loading buoys. The difference is that the aircraft has to be below HOGE, OEI weight at all times during the operation
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Bristow Caernarfon starting up.
G-MCGJ on site but not yet showing up on AIS or ADS-B, suggesting that the radio fit is not yet complete. G-MCGK arrived at Dyce a few days ago and is presumably there for a couple of weeks for engineering work. G-CIJX and G_CIJW are still at Norwich and often out around Cromer. No sign of a move to Lydd yet. |
Not much sign of a 189 yet then???:)
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Unfortunately, that aircraft is now not likely to deploy at the start of service at any of the bases that replace military flights. Eleven S-92A and some AW139s allows Bristow to equip nine bases without rushing the AW189. S-92A will stand in for AW189 in Scotland and AW139 in England and Wales. The original plan for availability levels that used one aircraft per base and spares at strategic locations appears to be back, for now. AW139 does not fulfil the requirements of a Lot 2 aircraft for number of survivors. On the plus side, it is looking like the AW189 will enter service fully equipped and certified. And, while we are waiting for the AW189, we still have new aircraft, a new regulatory framework, 78 managed transition aircrew and lots of new role equipment. It is what it is. Could have been worse. Could have been a MoD procurement. :E |
True Jim...true. In EU land, all prospective governments for the replacement SeaKing (the NH90) are facing revolts or cynicism about the new a/c as it is clearly unfit for purpose. Some countries have rolled over, like the belgians, others are fighting hard to prevent or atleast delay its introduction like the FGN. The practitioners do not want this lame duck but government procurers think otherwise. Meanwhile in the UK, we have the wildcat and the merlin as newcomers and one of those is incapable of being sent front line because of its lack of resiliance against enemy fire and subsequent repair costs. £40 million a pop and used only as a support vehicle???? Good old government.
Bristow have gone from zero to hero in what - 12 months, maybe less. Could you see the MoD doing that - yeah, right:ugh: |
There was discussion earlier about the AW139 and unprepared surfaces. Queensland Rescue did a medical call to a farm in Grantham. Interesting landings ;)
https://scontent-lax.xx.fbcdn.net/hp...39&oe=5609EA0F https://fbcdn-sphotos-a-a.akamaihd.n...423d5eec4866e6 |
I/C |
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G-MCGK arrived at Dyce a few days ago and is presumably there for a couple of weeks for engineering work. |
"de-icing issues affecting certification," More obfuscation because the de-icing wasn't included in that 'certification'? What about the certification of the SAR modes as that won't have been included in the O&G process? So the rumour is no NVG capability until September and we know that the 139 doesn't meet the contract spec - any financial penalties being awarded? Nice pictures John - does the 189 have similar ground clearance issues????? Great choice for a SAR helicopter! |
Originally Posted by ABZSpotter
(Post 8977908)
Not sure where you get your info from, but it isn't at Aberdeen.
(On the UK register. Flown by maker at Coatsville over 5 weeks ago. Shown as dereg USA 1st May, for export to the UK.) |
Originally Posted by [email protected]
(Post 8977916)
so what about the trumpet fanfare earlier in the year when the 189 achieved certification for O&G?
Originally Posted by [email protected]
(Post 8977916)
More obfuscation because the de-icing wasn't included in that 'certification'?
Originally Posted by [email protected]
(Post 8977916)
What about the certification of the SAR modes as that won't have been included in the O&G process?
Originally Posted by [email protected]
(Post 8977916)
So the rumour is no NVG capability until September ...
Originally Posted by [email protected]
(Post 8977916)
... and we know that the 139 doesn't meet the contract spec - any financial penalties being awarded?
Originally Posted by [email protected]
(Post 8977916)
Nice pictures John - does the 189 have similar ground clearance issues????? Great choice for a SAR helicopter!
https://vimeo.com/127840616 This is GN, which is the first Yeovil-built production AW189 in SAR config that includes the long range tank (that took too long, and was too heavy, and is too close to the ground). This is an ongoing concern for Land SAR operations. :ugh: ===================================== There is a report of Richard Parkes (Director, Maritime Operations, MCA) stating November for AW189 in service. That is credible. I shall put January in my diary, shall I? For Lydd but not Prestwick. :eek: (Wets finger and holds in the wind.) August 2016 for Inverness? :E |
Originally Posted by jimf671
(Post 8978286)
Listed by a spotter.
(On the UK register. Flown by maker at Coatsville over 5 weeks ago. Shown as dereg USA 1st May, for export to the UK.) All 11 S-92 delivered. |
What a pity it was not to be a one type contract, all S92 might even have kept Crab quiet.
Why do I always get that feeling of doom when I see Westland on anything, I wouldn't even buy one of there garage doors:{:{ |
Six Sea Kings from RNAS Culdrose performed a lap of honor today, ahead of the type's retirement:
Sea King flypast celebrates 76th anniversary of 771 Naval Air Squadron I/C |
Rumour Bristow being extra cheeky and using SAR 92 in North Sea to fly their own engineers out to rigs with U/S oil and gas aircraft on deck.......:=
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Are you the same guy that used to hang around outside the butcher's in Orkney?
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Well Sumpor (age 4) if I was one of the rig crew and there was a u/s aircraft blocking the helideck which was my preferred method of evacuation sould the rig have a problem then anything that helps clear the blockage must surely be a good thing. I'm sure the same would apply to another operators aircraft whatever the colour.
But if you are age 4 then you would probably not see that :rolleyes: |
Providing it wasn't the first standby aircraft then it's not really anyone else's business what they do.
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Originally Posted by [email protected]
(Post 8985561)
Providing it wasn't the first standby aircraft then it's not really anyone else's business what they do.
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Originally Posted by Ian Corrigible
(Post 8985239)
Six Sea Kings from RNAS Culdrose performed a lap of honor today, ahead of the type's retirement:
Sea King flypast celebrates 76th anniversary of 771 Naval Air Squadron I/C |
Originally Posted by Norfolk Inchance
(Post 8985793)
I wonder how much effort went in to get 6 'S' Mk5 HAR's airborne simultaneously??
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