Oz Report

Pre-Worlds interview

Pre-Worlds 2016|Raul Guerra|video

Raul Guerra «Raul Guerra» sends:

https://youtu.be/EG3_BC6lrPo

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Barrel release forces

Richard Thorp «rthorp» writes:

I have been laid low with sinusitis for the past week – so thought I would do a release force test on my barrel release – something that I have been wanting to do for a while:

I use the top black one in the picture - I forget the source of it but it is a thin wall aluminum barrel 3/4in inside diameter with a stainless steel curved pin.  The tension is limited by a single loop of the fishing line I have used as a weaklink since Hempstead.  I do not have a good way of measuring forces – I used a lever and baggage scale.  To the best I can determine the weaklink was failing around the 200lbf mark, so all the tests done were probably between 150lbf and 200lbf

Anyway.  At this “high” load of 150 – 200lbf, the top black release takes a VERY VERY strong pull to open it. It always opened, but the release force is MUCH higher than I am comfortable with.  You have to be sure to grip it properly when releasing.  I can really see how a first attempt could potentially fail.  It could be helped with a larger diameter ring around it so that if you slide your hand down the line there is a better shoulder to pull against.

I have another barrel release – the lower one with the red line.  This I made myself with thick wall Al tube 3/8in inside diameter and a straight parachute pin.  This is very similar in geometry to the ‘Getof’ release I have seen around – and is a design I like.  The combination of the straight pin that has a better mechanical advantage and the smaller tube means the release force is much smoother and very easy – 2 fingers can easily operate it.

So – what is the conclusion?. Well this is a personal question of risk tolerance, but for me I feel the 3/4in design is very marginal.  I am now not wanting to use it as my primary and have to fight with one hand off the bar to effect a release.  I also can see very little sense in using it as a secondary release – secondary releases will be used under high stress situations and often with an unpracticed hand with the release in an awkward position.  For approx $10 and 10 minutes work I can make up a much better alternative.

Just food for thought.

Personally, with hundreds of launches, I have not had any problem with the smaller blue version of the curved pin barrel release.  Thanks to Larry Bunner.

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2016 Santa Cruz Flats Race

Belinda Boulter|Bobby Bailey|CIVL|Flytec 6030|Jamie Shelden|John Simon|Jon "Jonny" Durand jnr|Santa Cruz Flats Race 2016|weather

This proved to be a very interesting day.  Lots of different flight aspects to deal with.

The day started with lots of cu's around and virga in the sky.  And I'm talking about shortly after sun rise.  The local forecast was for a 20% chance of rain.  It is rare to see cu's at all here so this was a bit over board.

We started off on the wrong foot with the wrong task given to the pilots at the pilot meeting.  No one caught it. The second turnpoint got renamed to a different turnpoint - LAPALM to PALMA on the task board.  Sent us ten kilometers further in nearly the same direction.  Zac had it right in his 6030 from the task committee meeting, but he was the only one.  We could have used a shorter leg at that point due to cu-nimb development.

We opened launch with rain pouring down to the south but blue to the west.  There was a forecast for a southwest wind at 10 mph, so the blue was supposed to come over us and dominate, or so we thought.

I was pulled up thirteenth behind Bobby Bailey and when we got to 1,100' I essentially got knocked off in the abrupt lift next to another pilot trying to work it. I pinned off and tried to recover from going sideways.

The lift was gnarly for the first few thousand feet but calmed down a bit as we climbed to 5,900' at a moderate pace of 195 fpm.  Then it started to rain, actually virga as we were in the air, not on the ground.  I headed south to get away from it.

The virga came coming time after time as I worked myself away from the cu's and in front of the virga to the south.  Up and down and getting wet which made for interesting decisions as I had to run away from lift to get out of the virga.  Virga was forming from even teeny tiny clouds.

The first clock at 1:45 passed and apparently no one was in a position to take it. I certainly wasn't at a little over 4000'. A bit later I climbed to a little over 6000' and headed east south east to again get away from the virga.  I saw a nice cu in that direction just beyond the 7 kilometer start cylinder and came in under John Simon, Pedro and Jonny.  Found almost 300 fpm there to a little over 6000' just in time to take the second clock at 2:05 PM.

Heading downwind to the northeast toward the first turnpoint at Signal Hill I could see a cloud street with rain behind me right on my course line.  I wanted to get away as soon as possible.  I wasn't particularly high but there were small cu's ahead.  It was about 15 km to the turnpoint and other than a few odd turns I didn't work much lift until I got to just before the hills and the turnpoint.  I'd often found lift in this area before as the ground rises and the wind was coming right into the heated rocks of the hills.  The turnpoint had a 3 kilometer radius around it so the lift was out in the valley but over rising ground.

I climbed to 6300' and five other pilots came in below.  Hit one more thermal on the way out to 6,700' heading south toward Palma (not LAPAM).

Off to my south west there was a large cu-nimb on the west side of Casa Grande.  I was on the east side.  The top was rising and the shadow was creeping across my course line.  The rain was falling hard under the cu-nimb but I didn't see a gust front (marked by dust). I hurried on hoping to stay in the sunshine and hit the little cu's to the east of the cu-nimb.

I kept checking to be sure that there wasn't a gust front.  The cu-nimb was huge and the shadow came over my course line.  I saw three pilots (Jonny, Kraig and another one) a little higher and going closer to the clouds.  I was not happy about the cu-nimb, but the air seemed okay.

Down to 3,700' I climbed back up to 5,400' at the edge of the shade wishing I was far ahead of this position half way down the leg.  Seven kilometers from the Palma turnpoint I say Kraig and Jonny just above me turning a bit to the west of me and went under them but didn't get anything.  I continued on and two kilometers short of the turnpoint and down to 1000' AGL found 160 fpm in smooth air over shaded ground.  I took it to 4,300' with no wind.

It was easy to make the turnpoint.  The cu-nimb had disintegrated but a new one had formed to its south and west.  I could see a gust front from it but it was till a long ways away.  I headed for the turnpoint and then found that I had entered in the wrong next turnpoint MARANO instead of MAGNANO.  I knew the MAGNANO turnpoint was to the northeast.

I canceled the task and did a GOTO MAGNANO.

Found 140 fpm north of the turnpoint to 3,800', but the lift was getting scarce over the shaded ground.  It was sunny to the north but that was currently out of reach.  Heading further north with three other pilots around I wasn't finding much just trying to stay up in near zero sink and drift.  Then I got a radio call from Belinda that the task had been cancelled.  I immediately landed in a huge hard packed field.

On landing a saw the lightning to the south.  Later three separate gust front came through but they weren't over powering.  Calm then prevailed as I broke down the glider with Belinda already there.

Jonny had contacted Jamie about canceling the task Jamie said that we are using the CIVL rules yet to be enacted that if a day has multiple start times the task is canceled instead of stopped for weather.  Jonny felt that there were plenty of pilots behind them and they would get hit by the cu-nimb at the PALMA turnpoint.

Zac took this shot.

The sport class Geckos from yesterday by Kelly Myrkle.

The after task drinking party two balconies away.

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Jamie Shelden⁣ is writing about the SCFR

Jamie Shelden

http://www.hgoutlanders.com/santa-cruz-flats-race-day-1/

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