Microlight Crash in Scotland - 2 Fatalities

[fisbangwollop]

The final moments before two die in microlight crash | Herald Scotland

[maxred]

Sentiments as those previously stated.

The images are quite startling, and God only knows why he would want to descend to app,100 feet over the summit, given the wind predictions on the day. Ben More is a lump, and, as all of the local flyers on here realise, all these mountain areas must be given the utmost respect, at all times of the year.

I have flown around these hills for years, and conditions change in seconds, weather features can form instantly, wave is a constant issue, and turbulence, can be a known constant. Every year GASIL always ran a piece on mountain flying, the do's and the don'ts, and the overriding theme was wind, down drafts and updraft's, transitting pilots should always pay particular attention to wind direction. Obviously they were lulled into thinking it would be alright, unfortunately, it was all very wrong.

[Shaggy Sheep Driver]

This is very sad. A couple of guys out with their mates in other microlights for a fly-out on what seems a lovely day and it ends in such tragedy.

A few years ago we were flying to Caernarfon in a Chipmunk. Surface wind at Caernarfon was less than 5 kts, so I was taken by surprise when downwind of Snowdon, north of the field following the Menai Straight, we entered the most severe turbulence I have ever experienced. The aeroplane was thrown about in all axis as well as vertically up and down. The stick and rudder seemed almost ineffective and wisps of rotor cloud formed and dissolved around us in the otherwise clear but tortured air.

I hardly had control of the aeroplane, but managed to turn away from the hills and descend, until thankfully we entered calmer air. Whatever the wind speed over the Snowdon range it was a heck of a lot more than 5kts! 40 or 50 would be nearer the mark! The venturi effect must have been boosted not only by the terrain but by the air mass above the mountains.

A similar but much smoother venturi effect caught a friend of mine instructing in a C150 at night in the Peak District. Surface wind at Manchester (who were vectoring them) was calm, yet they were forced down, despite selecting climb power and flap, in very strong mountain wave into the lee side of Kinder Scout, escaping with moderate injuries (the aeroplane was wrecked).

You don't have to fly within a few hundered feet downwind of a big mountain to get into trouble if there's a locally very strong venturi-induced wind.

[India Four Two]

The AAIB report and images are very sobering and thought provoking, for anyone who flys in the hills in light aircraft.

There are a number of documents available on the internet covering mountain flying. An example is the Civil Aviation Authority of New Zealand ‘Good Aviation Practice (GAP), Mountain Flying’ publication

I was pleased to see this reference in the report. I recommend this document to all pilots, even those who normally fly in the flat lands. There are several other excellent publications, all downloadable as pdf files, from:
Good Aviation Practice (GAP) Booklets

I42

[piperboy84]

The AAIB report and images are very sobering and thought provoking, for anyone who flys in the hills in light aircraft.

It certainly is.

[Gertrude the Wombat]

On a recent visit abroad (there aren't any hills in East Anglia) I asked about flying over the local hills (not that I wanted to, I was just curious about what precautions they took).

"We don't," was the answer. "But if we really want to we'll do so only on a day with exactly the right weather, and we'll be 2,000' above the peaks." This was in 172s, not microlights.

[dont overfil]

It's not just over the mountains there can be problems.

Last year I had 800fpm down (and up) 15nm south of Newcastle. The autopilot tripped as it couldn't keep up. The wind was negligible on the ground but showing 270/40 at 8500ft. We were 40nm east of the Lake district which I presume was causing the problem.

Fortunately it only lasted a few minutes. It took full power and a speed loss of 45kts to maintain altitude.

D.O.

[India Four Two]

I asked about flying over the local hills

Gertrude,
I'm interested to know where that was.

They would do hardly any flying with that attitude, in the Alps, Western Canada, Western US or New Zealand.

[flystrathclyde]

A step in the right direction

The 2 guys involved were from The Scottish Aero Club at Perth Airport and the incident was devastating for many of their fellow members.
Below is an extract from their latest member bulletin and they are making real efforts to help other ensure this type of incident does not happen again.

"On Wednesday 30th of January, Dai Heather-Hayes will lead a safety briefing on Mountain Flying - to which you are all invited to attend. This invitation is open to pilots from other clubs to whom we extend a warm welcome. Starting at 19:30, I urge all that take to the skies to attend. As with previous briefings it will be a good humoured and informative affair when everyone will have the opportunity to contribute. You can’t do too much of this stuff. The SAC is committed to the safety of its members and calls upon you all to continuously develop your skills, knowledge and responsibilities as pilots."

Well done guys for opening it up to the other clubs.

Allan

[cats_five]

Originally Posted by dont overfil

It's not just over the mountains there can be problems.

Last year I had 800fpm down (and up) 15nm south of Newcastle. The autopilot tripped as it couldn't keep up. The wind was negligible on the ground but showing 270/40 at 8500ft. We were 40nm east of the Lake district which I presume was causing the problem.

Fortunately it only lasted a few minutes. It took full power and a speed loss of 45kts to maintain altitude.

D.O.

The Penines often generate mountain wave which can affect anywhere downwind of them, and that sounds exactly like what you were in. Not sure how good a generator the Lakeland hills are, but I expect they contributed. A good resource for predicting wave (and thermal activity) is RASP - RASPtableGM

[The Old Fat One]

I have been reading this thread with some interest as my best friend has recently taken up microlighting and just soloed. Some time back I was searching pprune for microlighting info for him, and stumbled across this thread.

A bit of background. Although not a pilot, I was a full career aviator in the RAF and as both an aircraft commander and senior officer authorising officer on a squadron I was immersed in human factors, flight safety, CRM etc for over 27 years....so I've read, analysed and debriefed many hundreds of accident reports.

I have very little knowledge of microlighting (hence my questions below), but understand the very basics.

Finally, as a munroist, I'm very familiar with the venturi effect on mountains. by coincidence I traversed the summit of Ben More and its neighbour Stob Binnein, 3 days after this sad and tragic event.

My questions relate only the cause/effect and analysis of the accident. No judgement is intended. As an ex professional aviator it distresses me that aviation, civil and military, struggles so hard to separate the analytical from the judgemental. Accident reports IMO are integral to flight safety and any other purpose should be kept well out the way.

Apologies for the lengthy introduction, but my experience with pprune suggests if you don't make your intentions clear, posters will rip you a new one.

I have read the accident report in depth and discussed it with my friend. Two things puzzle me. I hope one or two of you microlighters out there can help me.

1. In overflying the summit (and hill walkers) at 100 ft, was the commander not in breach of the Air Navigation Act? This does not appear to be mentioned in the report (or is the link just to a redacted version of it?).

2. Although the commander was experienced the report says he only has one hour on "type". The keyword here being "type". I understand the ac belonged to the passenger, but if the use of "type" is accurate, it suggests he had virtually no experience of this "type" of microlight. Question...is that significant? Or are microlights so similar that it does not matter?

again I stress, these questions are asked for the purpose of helping a budding microlight pilot understand how human factors affect every part of aviation, in whatever form. No judgement of the commanders actions that day are implied or intended.

Safe flying folks, whatever your chosen chariot.

[Shaggy Sheep Driver]

1. In overflying the summit (and hill walkers) at 100 ft, was the commander not in breach of the Air Navigation Act? This does not appear to be mentioned in the report (or is the link just to a redacted version of it?).

My reading of the report is that the aircraft never reached the peak, but entered severe turbulence approaching the mountain, dived, and crashed into it some distance below the peak. The pilot did not therefore overfly the walkers on the summit and his intention may well have been to route around it, remaining at least 500' away at all times.

[maxred]

Summary:
The aircraft was being flown by an experienced microlight pilot who was accompanied by the owner, as 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.

Taken from the report............

[mad_jock]

your only in breach of rule 5 if you intentionally over fly a person who is visable.

Some stalkers tried to get an aircraft done for a rule 5 bust for over flying them and the judge rule that they were in camo gear and if the pilot can't see you then they have no way of being able to avoid you.

That was in a Scottish court so its common law now in Scotland. So if they were sitting behind a cairn or wearing DPM or clothes that blend in you can just say you didn't see them. If you had of seen them you would have avoided them.

But to be honest this is a mute point when the rules change with EASA because you won't be able to go below 500agl unless TO and landing unless your MIL.

[astir 8]

There had better be a continuation of the exception to the 500 foot rule for gliders ridge soaring!

[FlyingKiwi_73]

That kind of turbulence can happen even at low levels if the wind is right, I was still a student and only just past Solo, I had entered left base for Runway 30 at NZOM this takes you into a small valley right up against the hills.

I entered a downdraft which took me from approx 900ft to 400 ft very quickly, having 10 deg flap i had throttle full open and the nose as high as i dared and i was still going down. had i not flown through it horizontally i would have arrived very quickly on the valley floor and probably would not have survived.

Also had a few friends get into Mountain wave over the southern alps having to call CHCH Info as they were throttled back to idle and going up at over 1000 fpm and busting airspace. ASI firmly in the yellow. I those cases it would only take some misjudged sharp control inputs to induce structural failure.

FK

[gasax]

I started a post after reading the AAIB report and then thought better of it. I knew the pilot well enough to chat to occasionally and given his knowledge and general approach I fully expected that the cause of the crash would not be deliberately flying into the rotor of Ben More.

However it seems that is pretty much what happened, probably to get some good video of the summit. The report states there were no visual clues to the wind at height such as spindrift which is fair enough - although in my experience spindrift is pretty rare - snow here tends to be pretty wet and claggy so you do not see it often.

It is interesting that no data was recovered from the GPS. From my experience it is one of the best ways of sorting out what the local wind in doing and in all probability was showing grounds speeds in the 30 odd knot range - which should have been a very clear indicator of what to expect.

I can only assume that a decision was made to go and 'have a look' at Ben More on the hoff, the camera positioning meant that flying straight toward it was necessary and the position they made that decision in meant heading onto the rotor. I did not fly that day - I decided it would take 'too long' and be 'too bumpy' to go to the west coast but atually it was not a bad day, certainly nothing exceptional.

This report is a nasty reminder of how unforgiving our hobby can be when decisions are made.

[peterh337]

This report is a nasty reminder of how unforgiving our hobby can be when decisions are made.

That is true, in the sense that if you hit the ground in a plane, the results are not going to be good, but at the same time it is no rocket science to take one look at the MSLP chart, see the isobars very close together ( = strong winds), and to thus expect strong turbulence which that type of plane is poorly equipped for, in terms of both excess engine power and structural strength.

[Shaggy Sheep Driver]

it is no rocket science to take one look at the MSLP chart, see the isobars very close together ( = strong winds), and to thus expect strong turbulence which that type of plane is poorly equipped for, in terms of both excess engine power and structural strength.

Unfortunately it's not that simple. When it happened to me, and to my mate in the Kinder Scout crash, the isobars showed no such pattern. Local venturi effect of terrain and overlying air masses can have a massive effect on windspeed over high ground.

[peterh337]

On the contrary - I think it was a very windy day.

A witness on top of Ben More saw the last moments of
the aircraft’s flight but did not see or hear the impact.
He described the wind at the summit as “very strong”
and that when he removed an item of clothing from his
rucksack it was nearly “ripped” out of his hand by the
wind.

Over Scotland, the surface
wind observations valid at 1100 hrs UTC show westerly
winds of 10-15 kt with a 2,000 ft gradient wind of
310° at 25-28 kt. At Glen Ogle, near the crash site, the
surface wind between 1000 and 1200 UTC was westerly
16‑19 kt with gusts of 24-26 kt.

Was this data not available to the pilot, preflight? Form 214, etc.

I would think that a surface wind of 20kt is going to be 30-40kt at any altitude. It's one of the most basic rules in flight. And it veers to the right, etc, etc...

the isobars showed no such pattern. Local venturi effect of terrain and overlying air masses can have a massive effect on windspeed over high ground.

Mountains cannot make wind out of nothing, using some venturi effect. There has to be a general airflow, or updraughts by solar heating.