Freesteel Blog » 2014 » August

Monday, August 25th, 2014 at 1:53 pm - - Canyon, Cave, Hang-glide

I did get a very short canyon trip with an even shorter rope before expo was finished.

gcanyonrope

The canyon was called Salza Stauseeabfluss, and it went from the dam on the lake from Grimming. The rope was labeled at 80m, but no one had noticed it had been cut at 36m when they picked it up. We had to descend down the wall of the canyon in three stages off trees. We also got the walk out spectacularly wrong, and ended up clawing our way up a 60degree grassy slope in the dark.

This was on the same day I had a very nice 3 hour flight off Loser totally alone (due to west wind predicted) with a relatively low cloud base again, and tactically squeaked through the pass into the Bad Mitterndorf valley knowing that there was a good landing field there which I had used a week earlier.

gview

Unfortunately every single field including this one seemed to be full of tractors cutting and bailing hay. Fortunately, a bird appeared and showed the way up to the clouds after 15 minutes of barely maintaining height.

That’s one of the lessons from the 50k Or Bust Book: both time and place matters. Use your arithmetic to know that a slow descent rate of 0.2m/s is only 12m a minute (or 120m in ten minutes), which means you can stay in the game for long enough for the next thermal to rise.

Because the clouds were low, I didn’t want to stray up into the mountains, and stayed close to the valley where the lift was scratchy. The predicted winds were never materialized and I belly flopped on my landing again.

gfield

Here I am looking to the Grimming. If conditions this year had been equal to last year I would have got beyond it into the Enns Valley and maybe around to the Dachstein. This is the big target.

The annoying thing about flying is how quickly a good flight wears off on you. I was already fidgeting the next morning as though I had achieved nothing the day before.

Becka said something very mean to me last night: “You seem a lot more dissatisfied with life since you took up hang-gliding again.”

This needs sorting out. My original notion had to be to treat hang-gliding like skiing, where you go abroad on holiday to the appropriate place and do as much of it as you can to get it out of your system, and then come home and get on with normal life. But it’s not quite working out like that.

The final flight in Austria was in rough conditions and didn’t go anywhere, but the landing was perfect, like I was on autopilot.

gautlanding

Then the weather became rainy and normal for Austria, and we were into the depressing phase of bringing things down the hill and tidying up after expo.

We got away from the campsite at 5am in the drizzle and caught the 10pm Dunkirk ferry to Dover, although I did insist we stopped at the McDonalds in Zweibrucken because that’s where the previous car stranded me for two days in May.

gmacd

It was the highlight of the journey.

Saturday, August 16th, 2014 at 7:25 am - - Adaptive, Cave, Hang-glide

It rains and rains and just won’t stop. It’s also gotten pretty cold and I’m having to wear all my clothes that aren’t damp from lying in the tent. The last day of warm sunshine was six days ago where I stood on takeoff for 2 hours as paragliders wafted past and went down in the totally dead air of that day.
OLYMPUS DIGITAL CAMERA
See the smile? I want more flying. Some canyoning would be good too, but it ain’t going to happen on this trip.

When I finally took off I flew in a direct straight line across the valley beyond the highway and golf course, and then had to walk 5 miles back via an ice cream stand to Base Camp for a lift back up the hill, after which I drove down, fetched my glider, and drove back up again for the walk up to Top Camp (the Stone Bridge).
glideland
Here’s the outside view of Top Camp:
topcampsite
And this is the inside:
OLYMPUS DIGITAL CAMERA
It’s both a rock and a hard place with nothing in between, but it is still better than tents because it is larger, cavernous, and not like a box of damp fabric that progressively rots things as each day passes.

I dropped into the far end of Tunnockshacht down to the new connection to Arctic Angle. Becka was away with the Austrians on a different expedition and couldn’t warn me that it was going to be an unutterably deep one. That wasn’t the problem. The problem was getting terrifyingly stuck in a U-bend crawl while weaseling around the C-leads waiting for the guy with the drill to rig a rope traverse along a ledge of an undescended shaft to access the phreatic continuation. Then we surveyed about 100m until it crapped out, and hauled ourselves back out by 2am.

I forgot to take any pics, so here’s a photo of a nosy horse’s nose:
horsenose
On Tuesday I went to the newly discovered Balconyhohle. (The horizontal entrance is from a ledge within the side of a hole.) I was cold and had to keep eating. We killed a couple of going leads there too, but there’s enough unexplored ways on to keep this one spreading further underground. This has been the big find of the expedition. It’s a lot of work to keep up with the mapping.

Here’s a picture from the walk back to the carpark from Top Camp in the morning:
braungap

Since then I’ve been working on the Adaptive Clearing stay-down linking killing the bugs one at a time while all my HSMWorks buddies have been at a big planning meeting in Copenhagen this week. It seems like an endless grind. Anyway, I don’t plan to go there again, and the ferry between the UK and Denmark is being terminated this September.

One of the things that crashes the system is when the A-star linking can’t find a way to connect from point A to point B, and spreads out through every single cell in the dense weave until it runs out of memory.

One obvious solution is to generate a weave that has a wider cell spacing and solve the routing issue in it, but this is too complicated. I worked out another way, which is to deny it access to most of the interior cells of the fine weave that are nowhere near the boundary or on the theoretical direct line route. The A-star algorithm is so powerful that it will find a way round, even though the domain would look so much more complicated. This initial result becomes the starting solution for the linking path, on which the PullChainTight() function is called. This is actually a bad name for it. It should be called RepeatedlySpliceStraighterSectionsIn(), but this discription wouldn’t remotely be so compelling to the imagination.

This will get implemented only if absolutely necessary. The thing about the linking routine is that it does not need to work 100% of the time, because it can always fall back to the old way of retract linking, which is what everybody puts up with right now, so it might not be worth expending too much effort for the last 2% of awkward cases where the reliability is going to be questionable anyway. In software development the trick is to know when to stop.

Time to work on some cave surveying software today. Maybe I’ll get a flight in tomorrow. Hope so.

Saturday, August 9th, 2014 at 8:16 am - - Hang-glide

A week of sulking and being neglected by Becka while she went caved solidly came to an end yesterday when the weather broke and I got a four hour flight from Loser back to the Grimming, where I got to last year.

It was almost carbon copy of my 3 hour 2013 lucky flight, but this time I had better gear and I knew what I was doing — which was good as the conditions have been far more demanding in terms of low cloud base and scarcity of thermals below 2100m.

Here’s the picture in 2013:
OLYMPUS DIGITAL CAMERA

Here’s the picture now in 2014 with comfy neoprene bar-mits, an airtight harness that actually fits so I can stretch my legs and fly at the right angle, and an android phone running the astonishing XCSoar with its automatic zoomed in thermalling mode. The helmet and cheap sunglasses remain the same:
backtogrimm

Here’s the flight track with the Grimming on the right followed by a long uninterrupted glide towards home:
OLYMPUS DIGITAL CAMERA

Becka came along and shared a pizza with me while I rigged.
OLYMPUS DIGITAL CAMERA
Every time I do this I have to pinch myself that this is even possible.
OLYMPUS DIGITAL CAMERA
A tandem glider pilot gave me a 75% chance of getting up in the conditions. I let him go first to spot the lack of thermals for me, and barely survived when he went down in the initially cloudless conditions. Once I was high and conditions had developed I was able to fly cloud to cloud while deep in the mountains.
OLYMPUS DIGITAL CAMERA
I could have gone far if I wasn’t so obsessed with getting to the Grimming where I got swarmed by sailplanes.

The phone with XCSoar comes with a camera that’s better than anything else I own. I can take pictures with it if I don’t get too distracted or do something stupid like stall the glider trying to get a shot of the horizon. Here’s a picture of the Loser Plateau where Becka has been caving.
plateau1
We zoomed in to one section, and this is plausibly the tarp protecting the entrance of the stone bridge bivi cave.
plateau2
The cave was extended with a connection made to a smaller cave this year, and the total system is now 104kms in length, making it the second longest cave in Austria. When I get bored with flying, maybe I will go back to doing more of that. I do need to work on the cave drawing software a bit more.

Meanwhile, at the machine tool work, the bugs and crashes are being reported at a fast pace. I have got to get this working 100% by October. That’s the deadline I have set myself.