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-   -   Glider Crash at Ashbourne (https://www.pprune.org/private-flying/467634-glider-crash-ashbourne.html)

mcgoo 29th Oct 2011 14:16

Glider Crash at Ashbourne
 
BBC News - Cheshire girl killed in Derbyshire hang glider crash

Young girl killed in a glider accident. RIP

Whirlybird 30th Oct 2011 09:24

This is very close to my home and I'd like to know more. Does anyone know what happened? The school is highly thought of and I know several people who fly from there. The weather was lovely, and no, not a bank holiday. I'd really like some information.

The Heff 30th Oct 2011 19:45

The only other bit of information regarding the accident can be found on the Derbyshire Constabulary website.

The hang glider was reported: "getting into difficulty and falling to the ground from around 50 ft."

Understandably, no-one is giving any details to the press whilst an investigation is underway; so there's not much for anyone to discuss until the AAIB have published the accident report. However, this thread can still be used to express our sympathies for the girl's family.

Parapunter 30th Oct 2011 20:07

As a retired glider pilot - para division, I know the school & it's owners. No idea what happened & no intention of speculating, save to say that the owners are pilots of the first division with global reputations as anyone close to these people will know.

Hang gliding & paragliding whilst both mature forms of aviation in terms of equipment, training & procedure are still pursuits that carry risk of injury or death in common with all flying activities. They should be viewed in that light, but more importantly, thoughts should be with the family of the brave flyer who set out for an enjoyable day in the sky & didn't return.

ashbourne 31st Oct 2011 12:17

the pilot took off behind the tow microlight, and at about 50ft in the air, continued flying to the left of the tow craft until the tow rope was at quite some angle. either or both parties released the tow cable, but since the pilot was in a nose high attitude, with very little speed, it stalled and hit the ground.

Dave Gittins 31st Oct 2011 13:37

Do the AAIB investigate hang gliding accidents ? ... can't recall ever seeing one in the reports.

S-Works 31st Oct 2011 14:03

I think they are done by there own organisation same as the BPA does?

The Heff 31st Oct 2011 14:17

The AAIB are investigating this one. They've taken the crashed hang glider to Farnborough.

abgd 31st Oct 2011 14:29

I assume she was flying solo? I would have thought she must be a reasonably advanced pilot to be aerotowing.

My thoughts go out to her family and friends. It's grim for an accident like this to happen at such a young age.

Parapunter 31st Oct 2011 15:19

The procedure is the BHPA investigate all accidents, however, most incidents are not serious, relatively speaking so they stay within the gliding fraternity. Any death or serious injury is notified to the AAIB & they get involved at their discretion, as do the police.

If Ashbourne's information is correct, it appears to be a case of lockout under tow. static towing obviously produces a high angle of attack and leaves the towed aircraft much close to the stalling point than it would otherwise be in normal flight - power towing less so. If an aircraft deviates significantly from the tow direction, it becomes dangerous as safe turn inputs are reduced due to the angle of attack and either lockout or a spin can occur depending on the circumstances of the tow. The solution is to cut the tow line, lower the nose & re establish a safe course, in that order.

abgd 31st Oct 2011 16:39

Hmm... Low level stalls on a hang-glider, putting the nose down isn't always a good idea. It is obviously a good idea to keep the wing flying if you can, but with an unexpected release at a high angle of attack this may be difficult.

At very low levels sometimes it's better just to hold the nose level and 'parachute' down. If you pull the nose down you end up picking up speed and hitting the ground before you can fly out of the dive.

Fifty feet is a nasty altitude for this to happen - too low to pull out of the stall; rather high to parachute down without injury. And if you've dropped a wing then neither method is likely to do much good.

A more experienced pilot would have the skill not to let themselves get into a low-level lockout or have a large climb angle so close to the ground. But once in that position, there isn't always a good option.

Parapunter 31st Oct 2011 20:05

I know what you mean abgd, but for me, I think even at fifty above, I would sooner pull the bar in than tail slide to the deck. Thankfully, I have never had to make the decision.

abgd 31st Oct 2011 20:32

I agree that leaving the nose high would be a bad thing to do - wasn't advocating that. But I do disagree that it's sensible always to pull the nose in.

I'm not meaning to speculate on this particular accident, which may or may not have been recoverable - just wanting to counter the idea that there's only ever one option - to get flying again.

Parapunter 31st Oct 2011 20:46

No no, all very true. In fact what I wrote was a bit clumsy full stop. I was thinking of a static tow whilst also musing that the aoa characteristics on a power tow would be very different and fudging my observations on recovery.

However, in a desperate situation close to the ground, there is often just a split second to make the right decision & I've seen people, including me btw, make the wrong one & thankfully, get lucky - but not always. Very occasionally of course, there is no right decision & it's matter of being a passenger and hoping for the best.

Nonetheless, all things being equal & there being sufficient height to recover, the course of action would always be get the wing flying, then correct the course, then land.

astir 8 1st Nov 2011 09:18

15 years back I remember seeing a flexwing hang glider being aerotowed off a French strip by a flexwing. This was sufficiently novel for me to video it. The combination was up to about 30 feet and the glider pilot just tucking his feet into his sleeping bag when the rope broke or disconnected. The glider seemed to virtually stop dead in the air and descended more or less vertically with the wing still in flying attitude. The pilot hit the ground flat ( his feet were stuck in the bag). I guess there was some cushioning effect from the wing as he was OK (but very sore).

The lesson to me was to stick to sailplanes! But it seemed like there's a nasty period with an aerotowed flexwing near the ground where a launch failure is virtually unrecoverable.

Be happy to hear that I'm wrong though!

Could someone explain "lockout", "static tow" and "power tow" please?

Parapunter 1st Nov 2011 10:03

I'd be delighted - by static tow, I mean towing by winch & by power tow I mean being towed by another aircraft, I suppose more usually called an aero tow.

Lockout is the phenomenon whereby deviation from the course of the tow line causes the pilot to be unable to counter the turn away from the tow direction due to the tow line tension, resulting in rapid downplaning and usually a disastrous outcome. It's normally a deviation left or right from the tow line, but there have been lockouts where the towed glider overflys the tug aircraft & downplanes as the tow line tension causes the bar to be pulled in. Pretty rare though.

Here's a near lockout example:
Near Lockout Hangglider - YouTube

B4aeros 1st Nov 2011 12:54

Astir,

...there's a nasty period with an aerotowed flexwing near the ground where a launch failure is virtually unrecoverable.
That shouldn't be the case.

When I learnt to aerotow on a hang glider (90s) the trikes had a higher stall speed & flew faster than the gliders. We took off before the trike & had to hold the bar well back (ie stick forward/nose down) to stay in the correct position. If the weak link broke, there should be plenty of airspeed to remain in control & land ahead from 30'.

There was a chap on the same aerotow course as me who had a habit of letting go of the uprights & reaching for the basebar pretty much both hands at the same time. He was warned that this was not a good technique & inevitably, a couple of flights later, his two-handed grab for the basebar missed. The glider shot up into the perfect nil wind flare, nose to the sky, before crashing down from 20 or 30'. He was concussed but otherwise unharmed; the glider had the usual collection of broken aliminium.

I think lockout is more of a winch launch phenomenon. I've never heard of it during an aerotow, but it's been a while since I did any HG.

Parapunter 1st Nov 2011 13:19

I suppose the great thing with an aero tow as opposed to a winch is that the tug can move with the glider, if the tug pilot detects the lockout starting, whereas of course with a winch, it's fully down to the glider pilot to keep on a stable course.

I did my winch conversion on paragliders at Kemble airfield & I have to say it was one of the scariest sessions I ever took. The rate of climb is massive & the aoa so high that we were told that we could use no more than an inch of brake travel to control the glider lest we span & instead to use weight shift to stay on the tow line correctly. Great fun though & it beats walking up hills anyday.

truthinbeer 1st Nov 2011 23:14

abgd

Hmm... Low level stalls on a hang-glider, putting the nose down isn't always a good idea. It is obviously a good idea to keep the wing flying if you can, but with an unexpected release at a high angle of attack this may be difficult.
Not so. I saved my own bacon once, being sucked through a saddle on a ridge and into powerlines. Simple mistake where I mistook groundspeed for airspeed. Whacked that bar into my stomach and cranked a turn for an almost decent landing atop the ridge.

Better to have some control at impact than none at all.

A sad loss of a youngpilot.

abgd 1st Nov 2011 23:49

I disagree, in that I don't think it's always a good option - though I would always try to pull the nose down at least initially after a tow line break.

Suffice to say, it depends on the gliders, the circumstances and it's something to discuss with an instructor who knows the pilot and their glider.


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