Posted by Paul Naton on June 30, 2016
ALES & F5J Contest Tips & Lessons Learned
By Paul Naton Radio Carbon Art Productions
R/C Soaring How-To Training Videos
A few weeks ago I won the big two-day Polecat Altitude limited Electric Soaring contest (ALES) contest here in central Pennsylvania. For the past 5 years the Polecat has been the premiere North American e-soaring event with about 70 pilots from all over the U.S., Canada, and even Latin America attending this contest which features a whole roast pig dinner Saturday night.
I've won more than my share of Polecat mugs over the years flying a variety of gliders from an electric DLG in year one to 4 meter unlimited mouldies with lots of power. I even won one of the competition days with stock Radian foamy.
Even going into this years contest as an very experienced veteran, I learned a few personal lessons and wanted to share some tips and techniques that will help others do better in their next contest and improve their flying in general. These tips should be useful even if you don't fly electrics or compete.
If you want to just fly for fun, your preparations can be lax, just remember to charge the batteries and don't forget the beer. If you want to place well, your head has to be more in the game and detailed preparation is vital.
My prep starts with some practice the week before, and shooting some (lots) of landings as the contest will unfortunately be decided by landing points among the top guys. A little practice against the clock will greatly focus your mind and attitude. I also start to look at the weather forecasts as they will determine which planes I might bring and how much ballast and larger motor packs to bring. This year the Polecat forecast was for hot conditions with light winds so I left the heavy planes and wing-loading devices at home.
A day or so before the contest I hit the shop and go through the gliders nose to tail with FAA Inspector-like thoroughness to find any potential failures in the airframe, linkages or the wiring/radio system. I always find an item or two that needs repair or preventative maintenance, especially after a week of landing practice which is really hard on your systems.
For electric glider contests I make sure the entire motor system is in good running condition. I tighten the spinner collets or set screws, check the prop for damage, torque the motor mount screws, check the motor wire to ESC connections and the ESC to battery connections. This is stuff you should do monthly anyway. Most of the tech issues I see others having at an event are power system related and could have been prevented easily. I've seen props and spinners come off, ESCs failing to initialize, loose motors, and over-amped ESC failures.
I hate having technical issues at a contest (or even a fun fly day) and when I get to the field, I want to know that I can follow my pre-flight routine and step up to that first round flight line not worrying about the gliders condition or performance. Pre-contest preparation is a big confidence booster for any competitor.
Why Batteries Matter Lesson
For F5J and ALES events, having fresh and properly charged batteries are critical as you want to have as much power available as possible. Battery voltage sag under load limits your flat pitch speed and climb rate, and that ultimately limits your ability to go upwind or search for thermals under the altitude cut-off limit.
At this years Polecat I saw so many planes launch and instantly you could hear the prop rpms start dropping off quickly, telling me their packs were weak or not charged. A few pilots launched with totally depleted packs, costing them the heat and any chance of placing for the mugs. I see lots of guys that bring a whole bunch of motor packs to the contest and they don't really know which of the packs are old and tired and aren't up to a 30 second motor run without big voltage sags. I also see pilots flying multiple heats off the same pack without charging, that's not a good practice unless you have a small motor and a huge pack to feed it. Batteries matter!
I always monitor all of my motor pack's health with proper cycling and capacity checking. I'll never fly a contest heat with a pack that has shown any signs of a capacity drop or rising internal resistance measurements. I make sure I have at least 2 newer packs to use for a contest, and use the higher-cycle packs for practice only. Having a newer pack for your back up plane is also important. We're very hard on battery packs and expect them to have a very short life if you're using them past 25-30C discharges. I cover Lipo battery tech and performance monitoring in my Electric Sailplane #3 instructional video available at my site, www.radiocarbonart.com, if you want to learn more about this stuff.
For the contest, I take the two best packs and rotate them between heats, so I can charge them at a 1C rate safely and have one pack always fully charged and ready to go. I always use a pack voltage checker before the pack goes in the plane to ensure that it is indeed fully charged. A few years back I almost flew a fly-off heat with a mostly dead pack and once I forgot to initiate the cycle on the charger and thought the pack was done. Using the Lipo checker saved from disasters both times.
Polecat battery lesson learned: I was flying my Euphoria V2 this year and it only fits packs of 1200mah capacity or smaller. I had 2 newer 1200 Revolectrix packs for the contest that I rotated each heat. I hadn't thought of the fly-offs though, which are 3 heats in quick succession with no time to charge. I had to use a smaller 1000mah pack for the third fly-off heat, and this pack has seen many cycles! Of course the motor rpms and climb rate were noticeably less than the newer Revo packs, but fortunately for me the cut-off altitude was only 100 meters, and the lower power didn't keep me from getting to air I called. Next time I'll have 3 good contest packs ready in case I make the fly-offs.
Enough with the technical and preparation issues, let discuss some thermaling and air reading, that's what gliding and contests are all about.
Basic Air Reading Mistakes Lesson
The thermals for the two day contest were just superb. Actually easy. I got a 10 minute warm-up flight at 8 am on the first day. Sure there were some strong sink cycles, but the sink areas were small, and with the light winds, easy to fly through. You could not fly 300 meters without hitting lift. So why were there so many heats when half the planes were on the ground with 3-5 minutes left in the task? And these early landers were not always the Radians, there were also big contest birds flown by non-rookie pilots just dropping out of a sky filled with lift.
I watched the action all day and lots of pilots made the same 2 basic thermaling mistakes over and over. First was not having a game plan or air read before the launch window opened and just launching upwind with the pack. Second mistake was not reading the air well once you hit your launch altitude, and not making a quick decision to fly else where to find a thermal if the initial launch location was not working.
Like any man-on-man contest, you have some time before launch to look around and try to determine where the closest thermal is and if you can get to it by the time the heat starts. The Saturday Polecat conditions were a bit odd, huge lift all around, but very few ground signs with minimal wind shifts and velocity changes, only a few Buzzards up high and no high-percentage ground-based air reads. I think I had only one sure air read from a ground sign all day, and that thermal was way down field by the time the heat started. The lift 'threshold' was a bit high the first day, the threshold describing the minimal altitude required to be able to take a thermal out. It was just about impossible to thermal out below 150' for most of the day, as lots of pilots found out the hard way. So with the lack of ground signs, you were going to have to get off-field and go high and find a thermal on the way up or right after motor cut-off. My game plan for most of the day was to read the plane on the way up, and not rely on ground reads at all. That plan worked every time.
I just headed out to the higher spots around the field and read the planes drift and climb rate as I gained altitude. My Euphoria has a bit of power, so I use that to go out and slowly climb through as much of the air space as I can sampling the amount of drift I'm seeing and if I hit areas of greatly increased climb rate. I'll turn and change directions as needed to confirm a thermal read I might get. I'm listening to my radio's 30 second count down timer, and I want to have the plane right at the cutoff altitude at 30 seconds and hopefully in the thermal or darn close to it as glider bleeds energy after motor cutoff. If I read the plane right, the thermal will be in a 100 meter circle from my max altitude point and I'll just start a search pattern to find the best lift, and find it as quickly as possible. If I don't find the thermal I think is there or think it's too weak, I'l just go to my fast flight mode and go to another part of the sky without hesitation. I'll give myself 30 seconds to find lift after motor off, otherwise I will get the heck out of that area and find another thermal. The faster you make your decisions on where to go, the better.
So what is this drift attitude you use to read the air? I cover this advanced subject in full detail in my new Thermal Soaring Master Class video but here is short description: Reading the drift angle is a technique of finding the possible location of a thermal by watching how the glider drifts or yaws off course when influenced by the inflow currents around a thermal. Seeing and interpreting the subtle changes in your course angle while in flight is a hard skill to learn, but it's one of the best ways to find new lift in the absence of any ground signs or other lift indicators. My video goes deep into this subject if you want to learn more about reading drift. I used drift indicators to find my first thermal in about 75% of my heat launches at the Polecat. Often I could read the whole pack of planes launching and could see how they all reacted to a nearby strong thermal by drifting across the thermal inflow wind shift.
Move Your Butt Quickly Lesson
If you just launched straight up wind and at 20 seconds you hit 200 meters, you have wasted 10 seconds that you could have spent flying through more of the thermal space, increasing your chances of finding lift. Lots of pilots do this exact thing, hoping to find lift right off motor cutoff, then not moving fast and far if they launched into sink. I would often see 4 or 5 planes circling in the general area of the altitude cutoff height, perhaps in some lift, most often not, all trying to read each other for the thermal location. More often than not, none of them were in the good lift, and they all drifted downwind in semi-lift, then all sinking out together when the big lift left them behind. You must read your own plane first, if it does not want to circle or feels dead, get out of that area fast, you will have plenty of altitude at 200 meters to do 2 big search patterns and if you move out of sink quickly, your chances of getting 10 minutes go up fast. The thermals at the Polecat where everywhere, and even if your glider was of low performance, if you just flew some distance, you were bound to find lift. There was no excuse for not getting 10 minutes from 200 meters up.
Getting Down Safe Lesson
As our electric gliders are getting lighter and lighter, they do have their structural limits and you have to keep that in mind in stronger lift conditions. I spent most of my rounds dumping altitude for the last 5 minutes as I was launching into big lift right off and needed not to go any higher after a few minutes into the round. My Euphoria is a stout airframe for an F5J model, but it gets bendy at higher speeds and with the aft CG I like to fly at, I have to watch the airspeed and pitch departures. There were a few boomers on Sunday where I was in full camber #3 and the Euphoria was still screaming and climbing like a rocket. I've got the small and light MKS 6100 HVs controlling everything on this big 4 meter glider, and it was a real job to keep the ship from over-speeding, the first sign of that was loosing pitch control as the boom flexed and twisted at 60 kts. Just had to be conservative with the speed until I got out of the lift and able to work my way down safely and hit the landing without blowing up anything.
Landing Too Early Lesson
The only big mistake I made all weekend was to drop about 20 seconds off an otherwise perfect flight. How did I do that? I was killing time over the field with about a minute 30s to go, I was doing big circles staying up wind of the tape and out of the traffic. Lift was everywhere and it was easy at 100' and 45 seconds left to position for my usual pattern entry. At 40 seconds, the air changed, I could barely turn, the sink was coming in hard, and I was lower than I wanted to be! At 30 seconds I was at 10' and almost not making it over the wheat field and onto the grass. I had just enough energy to line up the tape and hit a perfect 50 landing, just I was 20 seconds early! That mistake cost me the Sunday daily first place and 3 positions. Got it all back in the fly-offs and the overall win. Lesson: I was a little too busy with traffic and visualizing a landing pattern to notice how strong the sink was and delayed a few to many seconds in adjusting my speed and altitude to the bad air. I should have noticed the changing air sooner and put some extra altitude in the bank before setting up for the last 30 second pattern. A basic mistake in situational awareness.
Don't Worry About Making Mistakes Lesson
Those who take the risk of making mistakes learn the most. Try new tuning set ups, make that crazy thermal location prediction and see if it works. Launch low, land early a lot, don't give up on that ragged little streak of lift. Walk for your plane once in a while. Don't always fly in perfect conditions.
I'm happy to answer any questions you might have about any of these subjects, contact me the usual ways or through the radiocarbonart.com website. To learn more about the subjects I've written about, I recommend my Thermal Soaring video series and my Electric Sailplane Clinic videos if you want to learn glider and e-glider building, preparation and flying techniques. - Paul Naton
Radio Carbon Art Productions
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