Archive for January, 2007

Ridge Soaring in the Hunter Valley

We don’t get a lot of opportunities to try ridge soaring in the Hunter.  Despite the abundance of likely-looking ridges, the wind never blows in the right direction.  The shape of the valley as a whole and the prevailing winds at this lattitude mean that strong winds only go straight up or down the valley.  Since learning a bit about ridge flying in New Zealand in 2005, I’ve been looking at one particular hill.  This hill forms a ridge that extends out across the valley for a short distance and it has a farmer’s airstrip at the bottom in case of the lift not working.  A North Westerly was blowing on Sunday so I decided to give it a go.

Here’s a diagram of my approach and initial climb overlaid onto a photo of the ridge:

Click for larger size in new window

 

Keep in mind that SeeYou draws the glider much larger than life-size so that it’s easy to see.  I have drawn on the picture some of the options I had available to me.  First, I approached the ridge with a good clearance above it.  Because the ridge slopes up to the left, it’s simply a matter of turning right over the lower ground until it looks good.  Then I kept the ag strip in sight and in a good position for a circuit.  The strip is much lower than the ridge, although it’s not obvious in the photo.  If I hadn’t found lift, at the point where the line turns red, it would have been an easy outlanding even though the wind is not straight down the strip.  This image also shows the classic figure-8 pattern I flew to always turn away from the ridge.  Each trip around the 8 is higher than the previous one.

After leaving that ridge, I moved on to the next one:

Click for larger version in new window

 

This viewpoint is looking exactly along my flight path as I pass through some 4-knot sink.  You can see that even though I’m in sink, I’ve chosen to cross the ridge at a point where I can safely clear the ridge.  The oversized glider icon obscures the small brown paddock I was aiming for as my primary outlanding option.  If this sink continued all the way to the ground, I would land in that paddock.

You can also see 30 seconds earlier in the flight I was in stronger sink - the blue portion of the flight path. You can see how I turned right after that, to choose the lower part of the ridge.  However the camera viewpoint is still above this flight path, so the brighter-green valley floor visible over the ridge is still reachable.  If the bottom absolutely fell out of the sky, another right turn would have put me on base leg for the paddocks I’d picked on this side of the ridge.

There were some very tempting ridges deeper into the mountains.  However at that height, in that wind, it would have been impossible to glide back to a landable paddock if the lift hadn’t worked.  “Aim the fuselage between the trees” is not my idea of landable.

The purpose of ridge soaring is not to scare yourself silly by getting close to the ground.  On this day, I was just trying to prolong the flight until the thermals started. Once they did, I immediately picked up a 6-knot average from the top of a ridge and climed to 5,000 feet.  I was able to do this with good safety margins above the ground and always having outlanding paddocks within easy reach.

Comments

We Need More Tourists

Comments

An unacountably good weekend

Comments

18 knots to 10,000ft

Comments