After months of discussion and theoretics, secret projects and bragging, the real men of slope and speed migrated to the Tri-cities in eastern Washington with weapons in hand to try there luck at setting the fast speed of the decade. All expected to fly Eagle Butte with its monster slope and thermal lift only to find La Nina had disrupted the Northwest weather again delaying the usual thermal-low “Columbia Gorge Vacuum” cleaner for another 20 days into summer.
So there you sit at Kiona (no slouch of a hill in its own right) with the temperature in the 80’s and just a light breeze sucking up the hill. You look down at your way heavy slope plane and wonder if it can thermal. You expected to launch out at a 24 oz. wing loading and in 10 minutes or so be high enough for that 200 mph run. It sounded easy. What everyone expected was not to be. Everyone got an event more challenging than any slope race.
I had just spent the last week in San Diego working at the Charlie Richardson (CR Aircraft) Skunk works designing and building a speed machine for Eagle Butte conditions. Charlie and I had been discussing designs for about 6 months; some concepts were radical but not practical. We knew what wing and foil concepts worked for high speeds and borrowed some tricks from some west coast speed 60” slopers I owned. I wanted a plane that could dive from any altitude with complete confidence and safety. That means wings that don’t bend or twist, elevator that does not flex, big servos, 6 volt pack, and a stiff tail boom. We had one week to finish the design and build this thing.
We ended up with a plane while not radical in design, met the design criteria for the event. The clean fuse is from his Raider F3B plane he sold for a while. We beefed up the wing rod area with epoxy and mounted carbon wing locator pins. The boom was stiffened with a carbon arrow shaft and spray-in expander foam. The wing rod is a 2 foot section of 9/16” solid cro-moly. We cut off the old glass vertical fin and glassed in a light but stiff thinner foil fin. No rudder needed. The elevator was a single piece of really hard solid balsa shaped to an 8020 type foil and glassed with 2 oz. cloth. While not high tech, it was fast to build and was extremely stiff in torsion and flex. That was bolted to the fuse with stainless steel bolts. (The plane needed to break down for travel.) An Airtronics 94161 Pro servo was used for the elevator, and a Hitec Supreme receiver and 6v 800mah pack finished out the insides.
The wings were the big challenge. Long wings flex and are hard and expensive to build strong enough in torsion. Charlie did some calculations and we came upon a 95” span as a good compromise with a 9.75” cord and 4.75” tip. That would put us at about 9lbs. at a 24 oz max wing loading and a nice 12:1 aspect ratio. The trade off was a little max weight but we knew that the shorter thinner wing would be stiffer and faster at high velocities. We started with the SD 6062 series foils which are known to be one of the best straight line speed sections and tweeked the shapes to minimize camber and thickness. We cut Spyder foam cores, installed a monster carbon tube spar almost full span with 1/4” Bass wood epoxied to the CF tube. Fred Sage bagged the wings for us with carbon and glass with plenty of gussets and glass on the bias. They came out like solid planks of metal, 23 oz. a panel.
One cool thing about the wings are the ailerons. To avoid any chance of flutter, we made them very small (12”) and mounted them way out on the tips. They were tubed with CF rod for extra stiffness and are driven by the super thin Volz Wing Maxx servos which barely fit in the skinney wing section.
The minimum all-up weight came out at 106 oz. with about 850 squares of wing area. She looked fast and clean, a bit on the heavy side, but REALLY stiff. The plane was named “Speed Runner” and I finished her off the day before the contest. How will it fly? To see some shots of the Speed Runner, go to my Endless Lift Soaring Videos website.
The web address is http://radiocarbonart.com/Pages/sead.html
So I pull up to Eagle Butte on Friday morning, no cars in site and the wind blowing down the slope. Not good. I can see some cars at Kiona Butte, some 8 miles across the valley. Maybe the wind will shift. There is no way my sled will fly at Kiona. I arrive to find US F3B team member Gordon Jennings already thermaling is Diamond F3 plane with speed master Espen Torp of the Norwegian F3B team getting ready to launch up. No one else is flying as the slope is not really working. I pull out my aging F3 Raider and put a bit of ballast in her and launch out for some practice runs. The thermals are pretty big and we sky out though things are feeling like we are flying Thermal Duration or HLG as you really had to work the lift that was moving around rapidly followed by just as big sink. Most of the other speed guys just had to watch us as only the multi-task planes could really stay up.
Gordon took some big dives at the course and it was apparent that you had to get really high to break 5 seconds and even higher to break 4 seconds. The off axis wind which was pretty laminer instead of vertical made finding a good line through the gates difficult. A few degrees off center of your dive angle and the head wind would kill your speed big time. I was a bit scared to dive my Raider down from that high up because it got a bit of wing tip bend at over 100 mph and had a tendency to tuck down. It was designed to slope race at Torrey Pines where turning and not terminal velocity is the name of the game. On my second dive from 1200’ feet she started to tuck and I had the stick bottomed out and it kept going straight down for another second or so before slowly pulling through the gates. Not a good run. The next run I came down from lower but as I pulled through level, the rudder started to flutter, ( I have a big full-flying blade on the back) and I decided to park it before something else went wrong.
One thing became apparent quickly; flying at Kiona was going to be a different ball game from flying at Eagle. You had to know how to thermal well, call air, feel when the wind would die or shift on the course, and judge your wing loading for the conditions. This felt like a combination of slope race, thermal duration and F3B tasks.
The times started getting faster as the pilots figured out the course and the limits of the aircraft. Most of the slope planes stayed on the ground as the lift was very cyclic. I think Espen got the first time under 4 seconds and Gordon started to get the line too. Later the slope lift kicked in a bit and Jennings flew his “Stink” , a special built plane built to incredibly strong specs for Eagle Butte. It needed more air though and it could not climb out very well. His plane did stay up though, and it gave me the courage to test fly the Speed Runner which had been waiting patiently in the pre-flight area.
US F3B team mentor and friend Phil “Bozo” Lontz gave my brick its first toss..........it flies! And damn, this thing really moves, but will it climb out? I hit a nice thermal and up it went. Cool. It even rolls OK, one thing I was worried about. I took Speed Runner through a quick check ride, testing for flight authority, center of gravity, and energy retention. This plane cooks and it feels so precise in the air. Time for a run.
I came down from maybe 700’ and did just over 4 seconds. I could tell I was no where near any kind of top end for this plane and it was rock-solid in pitch, which was very good to feel.
Timing these fast speeds was a challenge, and it took the hearty volunteers most of the afternoon to get a good system going. The planes where very high up making it difficult to coordinate both ends of the timing gates. Three timers with connected stop timers are at each end and click as the plane cuts the gate and the guys at the other end would click to stop the clock at the other end. At first there were large discrepancies in the times but this got better with time. The contest team did their best to keep things correct, but without some sort of electronic system (anyone got any bright ideas?), there will always be some human error involved. By the end of the contest the planes were going through the traps in under 3 seconds enlarging the error factor a bit. All of the top pilots were very close in times with only a few tenths of a second separating the top 5 guys. I think the planes were going faster than the watches were saying.
Saturday was the most interesting day with a building wind and actual slope lift. I flew all of the day at max wing loading as the Speed Runner continued to blow me away with its performance envelope. It could climb as high as the bigger F3 planes flying at lighter loadings and it continued to fly on rails at any speed; it was a very smooth airplane.
The testosterone level built up steadily as Espen and Gordon tried runs from higher and higher altitudes for that extra tenth of a second. Those who followed soon found the limits of their airframes. Bill Delhagen had a stab fin bend up just as he passed the first gate. The plane pitched negative in a micro second, the wings failed, then the whole craft hit the dirt with a tremendous smack and dust cloud that caught the attention of everyone. Soon after Espen Torp flying his gorgeous molded Wizard pulled through the gate from an ungodly altitude and lost the entire V-tail causing a cool pitch over. He actually flew the plane inverted for quite a while before crashing down right on top of a few guys looking for another downed glider. Another flyer a minute later flew his plane down a clean line but then forgot to pull up and the big plane dug a shallow grave for itself in the tough Kiona soil.
Dave Reese flying his knife-like Kestral pitcheron had some scary quick runs and had the fastest small plane out there. A few runs were so fast that his servos started to lock out and the plane started to do rolls on its own. Even some of the 60” class planes like Carl Boe’s Vindicator had some impressive 120 mph runs, but generally the smaller planes were about a second slower than the big planes and they were hard to see so far away in the big thermal waves.
A Canadian, Simon van Leeuwen, stole the show with a very fast 135 mph 2 way run with a modified Nova that put him in 1st place. He only flew in the late afternoon on Saturday and on one run his entire plane fluttered madly. Who was this guy?
Saturday finished with a giant foamy furball of over 30 planes, a new record for that slope, and the wind just kept going until early the next morning. Fellow Dynamic Soaring junkie Dave Reese and I had been checking out the ridge just a few hundred yards west of the speed traps. It looked perfect for DS, and I had been thinking for over a year that this ridge just might be have a DS “super groove” We took out Foamy wings and hiked up the rise, tossed off, and instantly discovered a monster grove. We were laughing and yelling loudly as out foamies got to flutter speed instantaneously. We landed and headed for the pits to get some real planes as the DS groove was very large and energetic. We soon had a whole crowd of guys and spectators at the top of the hill watching the show. Many had never seen DS except on video and were stunned to see the speeds we were getting. My Renegade 60” racer had never gone so fast!. Dave was flying his amazing Aircobra sloper and was getting way over 100 mph too. Everyone ran for cover behind the vans as the “Rev” Scott Hewitt cranked his huge and heavy “Mutha” flying wing round in huge and insanely fast circles building up tremendous energy. Everyone was saying, “why didn’t we test this spot earlier today?” We had a few DS rookies try their foamies out but they found out that DS can be very challenging! We flew until 9:30 pm, adrenaline exhausted.
Sunday was another hot day, no wind but big thermals popping. The few survivors of Saturday, mainly myself, Espen, and Gordon, launched out and got some huge convective lift. This was going to be our last chance to better our times. All of us were flying very heavy even though there was NO slope lift and huge areas of sink. It was very challenging staying up though once in lift, you could dot out quickly. Espen scored some huge air, and judged everything right and screamed through, doing a 2.26, the fastest time so far, and did a decent B/A leg to win the contest. I got one screaming average time keeping me in the running. I did a 2.35 on one B/A leg, but the lift completely died for about an hour and I had to land out negating my score for the average. Gordon Jennings did not give up, taking his Diamond to over 1700’ on two occasions. He was so high that you new something was going to blow up. Twice his plane “locked out” rolling out of the course but not crashing. Pretty exciting stuff. The lift died again and finally it was over.
The speed trails was a great event which challenged everyone’s skills to the limit. To win you needed a really stiff plane, excellent thermaling skills, and steady high speed flight experience. Had the event been held at Eagle Butte, things would have been a bit different. I think the speeds would have been higher, maybe below 2 seconds and 175 mph, and some of the slope rockets that could not fly well at Kiona could have set some fast times for sure. I know my plane was still accelerating before going through the gates. Some good suggestions were made by the contestants, and look for improvements next year like more classes, and lower entry fees. This was one of the most challenging events I have ever done. It sounded so simple at first......just go really fast for 200 meters.
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Paul Naton.
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