For Ed Levin Speed Gliding Contest 2012
Henry Bittner
Hey Guys,
I wanted to share my thoughts on the course as I have been thinking about this speed gliding meet night and day for the past year!!
I want to share the speed gliding basics with everyone so those just getting into it will know a bit more as to where to focus and where to fly. I learned a lot talking with others and sharing our tircks and theories only makes us all better as we can all build on these ideas. I learned a whole lot about what makes the fastest line through the course talking with Chester Brown about down hill skiing racing, and from JB, John Borton, the all time wizard of speed gliding.
There is an optimal line through 3D space, no matter what glider your flying. That line is pretty much straight between high points, or a Constant speed between high points on a curving course line. Attached is a picture of the profile and some calcs as to the best possible time through the course. The slope is about a 5:1 glide for the 1st half of the course. For my Combat L (given the polar from the web site) I would fly at a speed of 62 mph at a 5:1 glide. The second half is a bit steeper but given the turns and the need to aim about 20ft high going into each turn the slope drops down again to about a 5:1. The total distance is 1.33 miles. At 62 mph the best time with no turns would be 1 minute 18 seconds. If you add a second extra for each turn that would bring the best possible time to 1 minute 23 seconds. Brian's time of 1 minute 28 seconds was very good. Achieving a 1 second time to make a turn and stay on course is difficult and requires a tight turn with high bank (dangerous if your not used to doing this near the gournd! Take it easy at first) and starting the turn before the turn point so you dont drift too far below the course line. Looking at the videos from turnpoint 2 though the 6ooft control gate you could see why Brian had the best time and Kenny came in second with Eric third.
Have a look at the course profile. I made this last year using Google earth pro (trial version) to get the vertical and horizontal location of the turn points. I then plotted the course stretched out with no turns so we can see the optimum glide slopes. I plotted what I think is the optimum line in red. You see that the slope does not change much from 5:1. The makes the whole course a bit less challenging than other courses but it tests our ability to fly at a constant speed. The reason this is so important is you NEED to know how high to be above the turn points. Some turn points are below the course line and you don't want to get suckered into flying down to close to those points. (Note that I have the turn points miss labeled on this course profile plot, tp2 on the 2100ft ridge is suppose to be called tp1, tp2 is the turn point between this and the 600ft)
- course profile.png (17.26 KiB) Viewed 14777 times
I’ll give you my strategy for getting a 1 minute 25 second run. I would love to hear your thoughts on it and how it could be better.
The fastest run will be the run with the least changes in speed. A straight line between high points on the course (Constant speed!) is what will save the most gas (energy to be averaged over the course). If you fly too fast on one stretch, you will be forced to fly much too slow on ALL of the rest of the course. If you fly fast too early on in the course (like on the long glide from the start gate to tp1) you will really pay in extra time over the rest of the course, like 10s of seconds extra. Thus, it is critical not to fly too fast between turn points. To do this you need to learn to use PARALEXING on long straight glides, and fly at constant speed through the course over the low points. In 1998 we had a big speed gliding comp at Ed Levin. JB blew everyone away by 20-30 seconds. He told me latter that he did this by finding just the right bar position for the course. He would let out a bit to coordinate a turn then go right back to that bar position. He always felt he would be too high but he wasnt..He was a Man of Constant Speed. How to do this?
Start gate to tp 1 -When you go though the 1st altitude control gate look ahead at the 1st turn point on that far ridge. Find a spot just about 40 ft to the left of the turn point and about 20 ft above it. Notice the hills and bushes far behind this spot. Keep them fixed in your view. Do not let them drift up or down. You are on a collision course with this spot in space. You will fly at a constant speed in a straight line to this spot. IF you can do this you are using paralexing to fly a straight line. You can practice this walking around too. Anyway, the important thing about paralexing on this leg of the course is that it will not only save you 10s of seconds over the rest of the course, it also sets your bar position and air speed for the rest of the course. This speed will be almost exactly what you will use for the whole course because it is all about a 5:1. Memorize this bar position as you must go back to it after rounding each turn point all the way to the finish. You will think you are too high, your not. Keep this bar position. Just before the 1st turn point 40ft to the left and about 60 ft in front you start your bank for the turn. You let out on the bar and coordinate the turn, just clearing the turn point on the down hill side as you high side it and stuff the bar back to the 5:1 bar position you memorized on the long glide from alt gate 1 to tp1.
Tp1 to tp2 Aim again to be about 40 ft up hill from turn point 2 but this time you need to be about 85 ft above the ground at tp2 ( this is the tp just before the 600ft, many pilots were too low here and flew too wide). Too low and you have blown some precious energy and will fly slower all the way to the finish line, too high and you will only have flown slow for the shot distance between tp1 and tp2 (better to be too high than too low). How will you know what 85 ft is? That’s the trick to getting a fast time, knowing where to fly and how high to be above the “low” turn points that are below the course line and flying a longer distance. Start banking before the turn point while aiming a little up hill from the turn point. You need some turning radius and starting out a little wide is better than flying to the turn point and turning late and getting below the course line. Look back to the course line from the top view. Picture your path around the turn points. Where do you want to kiss the turn point and be setup for the next turn point? Sometimes you need to be extra wide going in. You should just kiss the turn point as you roll out of your turn and end up tangent to the line connecting the turn points.
Tp2 to 600ft – The 600ft is a high point so you want to be as low as possible yet too low and you will be forced to fly way around the hill and this will kill your time. Stay above the rocks, turn sharp and fly down the back of the spine (up hill side) to the 300ft. To do this well you need to aim about 40ft to the left (up hill) from the far alt gate pole, start a gentle bank early, then as you approach roll in a bit more and let out on the pitch so that you are halfway through the turn when your wing cuts the altitude gate. Your above the rock and carving right around in a constant bank to the course line down the back of the 600ft ridge.
600ft to 300ft alt gate – Aim for the space between the big water tank and the 300ft, or even wider, aiming for the water tank . Start you turn about 40-60ft before you are at the inner pole of the alt gate. Pitch out a little to carve a coordinated turn, dipping your wing to break the line between the tops of the poles. You can practice this dipping of the wing right where you want it at Funston by making a fast turn over launch over and over again. Drop that wing 10 ft above the wood chips in the exact same place every time. You’ll have it nailed down, the feeling or putting that wing where you want, and you can use it for these alt control gates.
300ft alt gate to tp5 to the Finish – You are aiming to be 100 ft above tp5 (above the trees by 30ft or so..I think.. check this out on race day). That will feel really really high, like you will not get down at the finish. Hold to that bar position but just a little faster, Now your really screaming though. They will hear you coming.. Aim for a point on the ground about 30 ft before the finish (Dr Steve Moris suggestion) to carry some of that energy through.
There, a 1 ½ minute run. Walk the course to the 1200ft tp1 and look at the course. Bring an altimeter and see what 85 ft looks like for tp2 as this is the hard one to judge, on tp 5 you at least have the trees and the 100ft launch to judge, but tp2 you diving into the gully, thinking about the alt gate on the 600ft, its easy to go too low there, and way too wide. Where is your reference to know you are 85 above this turn point when you exit the turn and stuff back to your 5:1 bar position?
Look at the videos from last year and you'll see everyone But Brian was way wide on the tp3 and the 600ft, and didnt start turning early enough approaching the 600ft alt gate.
..so in a nut shell:
If you start your turns before the turn point,
use paralexing to fly a straight line,
know how high to be above each low turn point,
and how to judge that height,
then you will likely get a flight close to 1 ½ minutes.
Tighten it up slowly and you will be right in there.
Here are some lessons form a few scary moments of speed gliding events past. If you VG rope breaks while you are close to the ground you can loop out of control and crash. Check your equipment. If you adjust your harness and something goes wrong with it, like it slips down and gets caught on the control bar, you can be stuck at 60 mph with no control. This has happened. We are loading up our gliders close to the ground, nothing is allowed to change with our equipment. Do not launch down wind with lowered sprogs and a tight VG.
Here are the results from last year..
Place - Name - Glider - Day 1 time - Day 2 time - Total Time
Rookie Class:
1st, John Hollander, Falcon 3, 2:55.78, DNF, -----
2nd, Mark Suttie, Falcon 225, DNF, DNF, -----
King Post Class:
1st, John Taylor, Ram Air, 1:53.2, 1:36.6, 3:29.8
2nd, Jason French, WW U2 145, 2:03.8, 1:57.7, 4:01.4
3rd, Mark Mulholland, Freedom 170, 2:19.8, 2:25.5, 4:45.3
4th, Robert Booth, Sport2 155, 2:08.2, DNF, -----
5th, Johnny French, Sport2, 2:14.8, DNF, -----
6th, Jim Bowe, Litesport, 2:26.9, DNF, -----
Open Class:
1st, Brian Horgan, Combat, 1:28.6, 1:18.6, 2:47.2
2nd, Kenny Brown, Litespeed, 1:38.9, 1:14.1, 2:52.9
3rd, Eric Froehlich, T2C 154, 1:43.2, 1:25.6, 3:08.8
4th, Ben Dunn, LS RS 3.5, 1:41.6 (+2 gates X 10 sec = 2:01.6), 1:13.8, 3:15.5
5th, Diev Hart, Litesport, 1:52.6, 1:38.2, 3:30.8
6th, Wayne Michelsen, Laminar Z8, 1:54.5, 1:39.6, 3:34.1
7th, Dirk Moris, U2 145, 1:47.3, 1:49.8, 3:37.2
8th, Zac Majors, T2C 144, 1:35.9, DNF, -----
9th, David Royer, Litespeed, 1:44.2, DNF, -----
10th, Pete Welch, Laminar MR2002, 2:12.1, DNF, -----
Optimum 0:01:23
Brian Horgan 0:01:29 0:00:06
Zac Majors 0:01:36 0:00:13
Kenny Brown 0:01:39 0:00:16
Eric Froehlich 0:01:43 0:00:20
David Royer 0:01:44 0:00:21
Dirk Moriz 0:01:47 0:00:24
Diev Hart 0:01:53 0:00:30
Wayne Mishelsen 0:01:54 0:00:31
Ben Dunn 0:02:02 0:00:39
Pete Welch 0:02:12 0:00:49
3 0:00:00
62
0.048387097 0:01:27
Last edited by hbittner on Sun Feb 12, 2012 3:47 pm, edited 6 times in total.
