Mad Jock perhaps under-states the levels of change necessary but at low level in this terrain the wind is massively powerful and varies from mildly helpful to pretty scary. How applicable that is to this incident no one is clear. Knowing the area and conditions it is unlikely they were low enough for this to be an issue.

But if you do go down to the level of the tops of the high ground life is complicated. Get anywhere near the rotor and all bets are off. So if you have to force land this is a major consideration.

I've picked a good old example of what can happen http://www.aaib.gov.uk/cms_resources...KG%2008-92.pdfI remember the day as being some somewhat worst than Saturday - if only due to the showers but the wind was also higher and from a different direction. But at that sort of height in Glen Muick you are on the 'shoulder' of the surrounding high ground and running into the lee of Lochnagar - a really bad place to be in terms of rotor and turbulence.

So here was a reasonable light aircraft with two experienced pilots onboard - probably overwhelmed by the weather.

https://www.sia.aviation-civile.gouv...2008_10_EN.pdf

The only sort of comparable place that I can find turbulence charts for is Vagar in the Faeroe Islands

http://www.slv.dk/Dokumenter/dsweb/G..._2_EKVG_en.pdf

For the briefing and

http://www.slv.dk/Dokumenter/dsweb/G...KVG_VAC_en.pdf

For the topographical chart.

Although in my experence when its says nil on that chart its bumpy, and light is pull in extra inch each side of your belt and shovel the sick bags off after you have landed. I was never brave enough to risk going in when it was defined as moderate.

I better not fly over the Alps again then...

Learn something every day.

But, seriously, would an experienced pilot not know that one needs to fly a fair way above the ridges to avoid the turbulence? Or is low flying a part of the thrill?

One rule I read somewhere, which doesn't seem far off based on what I have come across, is that you need 1000ft above the ridge for every 10kt of wind blowing across it, to keep downdraughts below 500fpm.

I really cannot imagine that any locally based microlight pilot, flying out of Glenforsa, was unaware of either weather risks, turbulence, or local terrain.

Many microlight pilots do however consider RT as something that mostly happens to other people. There are perhaps more arguments against than for that position but ultimately - ATC is highly unlikely to stop a non-transponder aircraft in open FIR from flying into a mountain.

And a day or two after the accident, any speculation is really total conjecture, including mine. This isn't a moral point - simply a statement of fact, nobody knows. Yet.

I hope and trust however that AAIB will make sure we do as soon and as thoroughly as they can.

As I said, I'm making no moral point, just saying that until AAIB have done their job, I simply wouldn't trust any conclusions drawn by anybody else.


What is clear however, is that two of our fellow aviators have died, and their fellow pilots, and their friends and especially families, have suffered an awful loss. For this, my deepest sympathies to everybody who knew the two men.

G

The group had planned to transit at 7000ft.

I have heard Scottish Info issuing sigmets today for strong wave. Wind is 5-10kts stronger today. Backed by about 10 deg.

MJ I see you have 100kts at FL240 today. I'm glad I don't HAVE to fly.

D.O.

I have had 3000ft/min in a Tommy South of Aviemore and when you get that your more than likely to find somewhere else thats doing the same going down.

Peter they have got something over 35 000 ft nearer 40k altitude records gliding in that area of Scotland on the mountain wave.

I don't know if the Alps has local conditions that you need to be careful with. I have never been able to take a direct routing across the Alps due to drift down performance.

Not flying in Scotland now unfortunately. But the 214 isn't showing it that strong.

Westerly at 20-30 knots freezing level 4k up north and 8k down south so nothing special.

F214 09.00 to 15.00UTC 55N 00E 230/100 -23

D.O.

Are you sure about that and you haven't got yesturdays?

The metoffice current 214 has it dropping off as that low pressure moves north.

Surface pressure charts - Met Office

Most decidedly. All mountains do. Even small hills do - you can get the 'clutching hand' effect where the wind isn't straight on and is flowing over a spur. The briefing notes for soaring the South Downs Ridge (done in a NE) make this very clear.

Let me add my voice to those who say we should not speculate. The reports suggest the captain was very experienced. So many things could have gone wrong. Perhaps it is a small crumb of comfort for the families to know that the AAIB is the best in the world if it is possible to find out what caused this terrible thing to happen to their loved ones then the AAIB will most certainly find it.

My second point is that the comments about using R/T are in my view, important and not peripheral. I was flying in this area last week with plenty of showers, low cloud and bumpy air all over the region. Tuning into Scottish Info meant that I could build up a really good situational awareness of what was happening with the weather. I found out the altitudes and locations where some were having difficulty with icing, where zones of IMC were appearing all over southern and western scotland, and also who was going from where to where and which of them turned back and where. That, together with a quite superb service from Fisbang and his mates, who must of been tracking me by radar (else their Dead Reckoning is better than mine) made for a much less stressful journey back South. Radio isn't compulsory, but I would use it every single time.

2high.......Glad you guys had a good trip last week and you found the service we provide of use........as for radar, no radar but an airspace infringement tool yes.......as for my DR it's pretty good using my 1: 500,000 chart, whizz wheel and my piece of string. Look forward to your club venturing north of the Border again soon. :cool::cool::cool:

Some poignant pics here

Final moments of crash microlight - Telegraph

What might possibly be surprising to some (?) is that the Wx / Viz looks great, so perhaps easier to understand why an old hand and experienced microlighter like Dave succumbed ?

I've experienced significant turbulence on occasion in similar conditions in Scotland, on one occasion at 600 feet over the flat Stirling Carse which scared the bejeesus out of me. Conditions on the ground gave no indication whatsoever that we should have stayed at the field and put the kettle on again, nor was the Met flagging up anything other than typical Scottish weather which does of course counsel caution a lot of the time

Loads of flat bottom clouds which I would expect to have loads of lift under them. And also loads of holes in the clouds which i would expect down drafts in.

And no it wouldn't suprise me to have areas of turbulance with the limited picture you can see.

AAIB Report
 

Air Accidents Investigation: Pegasus Quik, G-CWIK


Synopsis
The aircraft was being flown by an experienced microlight pilot accompanied by the owner, who was a passenger, occupying the rear seat. They were transiting from Perth to Glenforsa, on the Isle of Mull, at about 6,000 ft, above scattered cloud. Approximately 2 nm east of Ben More mountain, in Stirlingshire, the aircraft descended in good visibility, remaining clear of the cloud. The descent and flight up to one second before impact was recorded on a video camera attached to the aircraft. The aircraft levelled off below the cloud base and approximately 100 ft above the summit of the mountain. It continued towards the mountain and encountered severe turbulence in the lee of the summit. This appeared to cause the pilot to lose control of the aircraft, which impacted the south side of the summit, fatally injuring both occupants.

Sad reading, RIP lads.

UA

Aye could have happened to any of us.

The group that flew out that day were aware of the possibility of severe turbulance and had planned to track south of the hills. Why Dave went against his own judgement once airborne is anyones guess. RIP.

D.O.

Mad Jock

Agree with you, but my point is the deceptive seduction to fly lower than advisable on such days, which none of us are immune to - I'm certainly guilty of it albeit with the calculated risk as much in my favour as possible ? Turbulence is a common feature of mountain flying as you say and arguably 99.99% of the time doesn't result in fatalities.

DO, I agree with your sentiments, a tragic loss all round

DO, as much as it pains me to say it I think the fact the GoPro was turned on right before starting their descent towards Ben More probably says it all. I suspect they found the conditions at 6000' better than expected and decided to get some nice footage of the summit, the sort of thing I'm sure we've all done at some stage.

Their but for the grace of god.....