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Oct 30, 2010, 06:12 PM
Dave Register
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US ALES (Altitude Limited Electric Soaring)

(Day/Date TBD)
Bay Area R/C
CD - Allen Strahm
Please see Bay Area R/C Blog for additional details:

July 30, 2011 (Sat)
League of Flight By Thermal (LOFT), Ft. Wayne, IN
CD - Ray Hayes
Please see LOFT web site for additional details:

Jul 30th, 2011 (Sat)
Orlando Buzzards - AMA required
See FSS web site for updates (Jan 8th contest reference)

July 31st-August 1st, 2011
ALES One Class Contest.
Sunday- Practice. Monday- Contest.
MAAC or AMA required.
Okanagan Falls. British Columbia.
CD. Ken Gregory
[email protected] For details and Registration.

August 7th, 2011
Greater Detroit Soaring and Hiking Society
Addison Oaks County Park just north of Rochester, Michigan.

August 27, 2011 (Sat)
League of Flight By Thermal (LOFT), Ft. Wayne, IN
CD - Ray Hayes
Please see LOFT web site for additional details:

September 3rd, 2011 (Sat)
Charles River R/C

September 4, 2011 (Sun)
DARTS - Altitude Limited Electric
CD - Ed Franz (seeded MOM scoring)

September 9-11, 2011 (Fri-Sun)
Albuquerque Soaring Association-F5J Electric Soaring World Challenge
McIntosh, NM (Sod Farm south of Moriarty, NM)

Oct 15th, 2011 (Sat)
Mid-Florida R/C - AMA required
See FSS web site for updates (Jan 8th contest reference)

November 26th, 2011 (Sat)
Soaring League of North Texas - AMA required
12pm – 2pm, 4801 W Pioneer Pkwy, Arlington, TX 76013
CD - Dan Ahearn
Please see club web site for maps and other schedules
Last edited by okiesoar; Jul 30, 2011 at 11:30 AM. Reason: Add additional contest listings
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Oct 30, 2010, 06:16 PM
Dave Register
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US ALES Forum - Purpose

This forum is being started to provide information to soaring pilots in the US about the new ALES (Altitude Limited Electric Soaring) format. It will try and provide information on equipment and contests, as well as building and flying hints to help US pilots enter this program.

It is not intended to be a forum for rules discussions or tactics. Several of those groups already exist and are quite active. I would encourage contributors with such interests to join those existing forums.

A group is also being formed on Yahoo by Don Harban (for similar but somewhat broader purposes - including rules and international).
The Yahoo forum is very good at providing archived material and links whereas RCG appears to be convenient for threaded discussions. Hopefully both groups will ‘mirror’ the other in areas of commonality and will serve the needs of the growing number of ALES pilots

To my knowledge there have been 5 ALES contests flown in the US. I’ve been fortunate to have attended all of them - along with approximately 70 other entrants. My impression is that US pilots have enjoyed the events and I encourage those experienced competitors to share their ideas with pilots who might like to evaluate this type of flying for the 2011 season.

A couple of things to cover in the next several posts:
- A brief history of ALES development in the US,
- A brief overview of the event format,
- Where to get the altimeter switches and a brief comparison of their features,
- A review of the 2010 contests

There are now enough ALES participants in the US that there should be a lot of qualified feedback to most questions. I’ve thoroughly enjoyed all of the 2010 events and am looking forward to the continuing development of this event. Hopefully the RCGroups and Yahoo forums will provide useful information for more pilots in 2011.

- Dave Register
Last edited by okiesoar; Nov 17, 2010 at 02:54 PM. Reason: Put contest listing as the first post
Oct 30, 2010, 06:57 PM
Dave Register
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History and 2010 US Contests

A Brief (And Incomplte) History of ALES in the US

Any summary of ALES is, of necessity, somewhat limited. I can report what I’ve experienced and encourage others to add to this background.

There are many soaring groups that have looked at the ‘winch-in-the-nose’ concept for thermal duration events. Basically, put an electric motor in a sailplane and let’s fly. I’m not from an electric background and can’t really describe all the many directions e-soaring has gone in the past. But a few years ago it was obvious that my skills in DLG were diminishing (well, relatively speaking – they weren’t much to start with) and lugging around a winch was a pain when you fly solo. Since one of my destinations was Albuquerque (Blue Skies – a great DLG series) and one of my OFBs was Dale Nutter, I got wind of the Outrunner class ASA had been sponsoring for several years. The trip out there last Fall found Buzz Averill espousing a format that used a limiter switch with a preprogrammed altitude or time for launch (whichever came first). Talking with Dale and Buzz and Bruce Twining got the adrenaline going and the more the concept was analyzed on the drive back, the better it sounded. At that point Buzz was organizing a group buy of the #2 BASIC altimeter switch and I got on board and have been hooked ever since.

Meanwhile, a number of other flyers had been using other devices (the Z-LOG seemed to have been quite popular) which provided a motor cut-off at a preset altitude. These devices did not incorporate the clock function (insofar as I understand) and the guys using the Z-LOGS speculated ‘wouldn’t it be great’ to have a time cutoff to level the playing field a bit. Randy Brust at Soaring Circuits (maker of the RAM altimeters) was working on just such a device as well and began providing prototypes for evaluation by a few pilots in the US and abroad throughout late 2009 and early 2010.

Over on the other side of the world, Palo Lishak in Slovakia had been formulating rules for an event that precedes the US ALES effort by several years. Palo’s leadership appears to have spurred the development of the #2 BASIC switch and other similar devices to facilitate this general flying format in Europe and elsewhere.

Meanwhile, the British Model Flying Association (BMFA) had picked up the Slovakian concepts and published a set of rules to formalize a contest circuit in the UK. With this description in hand, the Altitude Limited e-Soaring format in Great Britain has apparently been rapidly growing over the past several years. And in Slovakia (and the general euro-zone) it has become popular enough for Palo to sponsor a World Championship event for altitude limited soaring. While here in the US, ASA received their switches, Soaring Circuits perfected the CAM and Tom Kallevang lobbied LSF to add the Altitude Limited format to the NATS as a provisional event. Things were starting to pick up.

And that’s about where we were in the beginning of 2010. More on the US story in the next note. If other contributors can elaborate on these notes, please do so.

The US Contest Circuit for 2010

As previously mentioned, by early 2010, the general concept for ALES in the US was working out. Albuquerque formulated their rules as an outgrowth of their Outrunner LMR experience. These rules closely parallel the BMFA description for the event. In February, 2010, the first US ALES contest was held at the sod farm in Moriarty, NM. A brief write-up is posted at post#27:
This contest proved the concept and rules were viable but had to be cut short after 2 rounds when a vicious cold front came through.

At essentially the same time, discussions were being held among Tom Kallevang, Ed Franz, Randy Brust and a few others about the possibility of sponsoring a provisional event at the NATS in Muncie. Tom’s support from LSF was instrumental in this being placed on the schedule. Shortly after that, an ad-hoc group (the above plus Denny Maize and myself) started discussing provisional rules for the NATS and settled on a provisional description based largely on the BMFA example that had met with good success in the UK.

The ‘pucker-factor’ of running a new, untried event at Muncie inspired Denny Maize to sponsor the first full 2-day ALES contest in June at Carlisle, PA. Denny’s medical challenges over the past several years had made continuing the well-known Polecat Challenge F3K contest impractical. But the new ALES format seemed manageable so Denny passed his F3K weekend on to Bruce Davidson’s ‘The Bruce’ contest and went with ALES for the same weekend. This contest was well attended for a brand new event (roughly 20 guys flying two classes for 2 days). The RCG thread for Polecat ALES can be found here:

So ALES in the US was off and running and the next stop was NATS. The rules as used at Polecat seemed to work well and were used in Muncie. ‘Official’ length scoring tapes were made (which now reside in Don Harban’s contest kit – more in the ‘resources’ note upcoming). And 19 or so of us came to Muncie for the party (well, 18-1/2 as one over-slept that morning but it had been a tough week). The Muncie experience seemed to work extremely well and a summary can be found here (starting at around page 5):

Next stop on the US ALES circuit was Albuquerque for 2-days of fun (in the sun this time!) at the sod farm. The ASA rules are slightly different from those used at the NATS (mostly in the window timing and landings) but the intent and character of the contest is essentially the same. This contest drew approximately 20 folks in each of two classes. ASA flew the ALES format with 2.3M and under and Open class events. It’s interesting to note that several pilots flew their 2.3M ships in Open and brought home hardware in both classes. The RCG forum for this contest can be found here:

Now to wrap up the season, the Dayton club (DARTS) enlisted Ed Franz as CD to run a 1-day ALES event in October. As with the first, the last saw some inclement weather blow through but still garnered 15 pilots to fly 3 rounds before the cold front tried to wipe us all out. As with the previous contests, no clear dominance by any sized plane or power plant was seen. Radians were competitive and everything from 2M ships to 3.5M e-AVAs successfully competed. The discussion for this contest can be found here:

That about covers the US contest scene for 2010 for ALES. A lot has been learned and a lot of good flying is under a bunch of good wings. Over the next few days some of the resources available for US-ALES pilots will be reviewed and, hopefully, the US pilots will offer insights based on their experiences to date.

- Dave R
Last edited by okiesoar; Nov 05, 2010 at 12:32 PM. Reason: Move Post 2 to make room for 2011 contest schedule
Oct 31, 2010, 06:27 AM
Dave Register
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Altitude Switches

The enabling technology for ALES is the altitude switch. It’s basic requirement is to shut off the motor once the target altitude or time has been reached – whichever comes first. The currently agreed upon altitude/time for this task is 200 meters or 30 seconds. All of the units to be described provide some level of programmability to change these targets. Each one implements this functionality in a slightly different way.

In the first picture I’ve shown the three altimeter switches available in the US (or from a US distributor). The background lines in the pictures are all on 1” centers. The web sites for these devices are listed here (in 2 cases the units are imported and a second reference is made to the originating web page):

Soaring Circuits CAM (US)

BASIC #2 (Slovakia)

Shread-RC (Russia?)

Each limiter is viewed separately for details in the following pictures. Finally, a CAM is shown for size comparison with a 3S 900maH LiPo pack and a 20A ESC. As can be seen, the switches are about the size of a rather small receiver.

We’ll review features of each unit in the next message.

- Dave R
Oct 31, 2010, 07:08 AM
Dave Register
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The various altitude switches provide several key features which we’ll briefly compare here. This is not necessarily an exhaustive list but includes the options I’ve used with all three.

Connection to your System:
All units simply plug in between your ESC and your receiver. The switch must be plugged into the same connector on your receiver as is used for normal throttle control. Since the switch intercepts the low level logic signals to your ESC, any size ESC may be used with any of these switches. On the CAM, a pig-tail wiring is provided for both sides (male/female). On the BASIC and Shread, a normal JR-type plug goes to the receiver and a set of pins on the circuit board are provided to plug in the ESC to the switch.

On my gram scale I get:
CAM ~ 7g
Shread ~ 5g

CAM – The original CAM is firmware set to 3 altitudes: 50m, 100m and 200m. A recent firmware option provides alternative limits of 100m, 150m and 200m. (I prefer the original with a 50m option). The time is fixed and set for 30s for all altitudes. The CAM is programmed with stick movements which are activated by a high-throttle position at power-up. Confirmation of the programmed altitude is with a series of audible beeps.

BASIC#2 – This unit programmed via a USB interface to it’s controlling/reading program. It may only be programmed via this interface and requires a PC connection. Alternatively a separate FXJ programming card is now available for field changes. Using these interfaces any altitude and time (within reasonable limits) can be programmed. Once programmed, there is no indication of the altitude or time values that are targeted. A flashing LED will provide a coded read-out of the max altitude attained during the flight.

Shread-RC – This unit is programmed with a series of jumpers that are preset for 200m/30s, 150m/25s or 100m/20s. Plug in the jumper across the appropriate leads and it’s done. No audible or LED indicators are provided to highlight the programmed targets.

Start-Up Features:
All units allow a user to ‘pop’ the motor briefly to check for overall system operation. The CAM re-initializes on low throttle. The Shread allows a 7s window for motor check-out. If that time is exceeded it must be reset (powered down). The BASIC allows a brief motor run before latching the timer/altimeter.

Shut-Off Features
CAM – Once the target altitude/time has been achieved, the CAM shuts off the motor and does not allow a re-start until the unit is reset. Resetting can be achieved by taking the throttle to the full-low position.

BASIC#2 – Once the target altitude/time has been achieved, the BASIC unit shuts off for approximately 10sec and then re-starts. Consequently, within 10s the throttle must be returned to the off position once the motor has initially shut down.

Shread-RC – Once the target altitude/time has been achieved, the Shread-RC shuts down and cannot be re-started until power is cycled fully off in the plane. In practice I’ve found this requires ~ 3s of disconnect to be sure the circuit is discharged.

CAM and Shread ~ $50
BASIC ~ $130

Other – the BASIC includes a data logging feature which downloads fight logs to the PC. This log also indicates motor run and shut-off actions. This unit also has a firmware modifiable anti-zoom algorithm.

Hopefully that covers the major operations of the CAMS. Questions can usually be addressed by accessing the respective web sites for each unit. Or post here or on Don’s form and we’ll try and answer.

- Dave R
Last edited by okiesoar; Oct 31, 2010 at 07:15 AM.
Oct 31, 2010, 07:52 AM
Dave Register
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Operational Comments

OK, here I could get in trouble. I’ve used all three switches in competition during this past year and have several observations. Consequently I’m going to be expressing an opinion and a preference. Not everyone will agree but as one of the experienced users of these systems it seems appropriate to reflect on what I’ve seen this season. In order of preference:

CAM – As with all units, I’ve cross checked the cut-off altitude against my RAM2 and RAM3 and found it to be well within the targeted specs. Time cutoff is as close to 30s as I can get with my stopwatch. I have over 300 flights with several CAMs and have never had problems with any of them. The audible signature at start-up tells me exactly where it’s programmed (very useful in the last contest!). The field programming allows quick changes from practice altitudes (50m is preferred) to contest altitudes (200m). The CAM has been positioned in several places within the equipment area of the canopy with no interferences being observed. I like the hard shut-off that does not require flipping the throttle switch to ensure the motor stays off. I similarly like the reset option as it allows a ‘save’ (albeit with a zero score in a contest) if the plane is in real trouble. I’ve never used that option in a contest but it’s good to know it’s there. And it’s really handy for practice.

BASIC – Again, the altitude and time cross check to my RAMs and stopwatch demonstrate similar accuracy to the CAM. I have ~ 150 flights on this unit and have used the data logging feature occasionally to check the zoom and other flight profile features. The lack of a preset indicator at start-up is a minor annoyance as I know I can’t re-program it at the field - wherever it’s set, that’s where it stays. The reset after ~ 10s was a ‘gotcha’ for me at first. In the heat of battle (or practice) I sometimes forget to take the throttle low after shut-off and this was disconcerting until the old dog learned the new trick of flipping the darn switch (BTW, this only happens after you’ve dropped below the shut-off altitude). Placement of the unit within the equipment area seems sensitive to proximity to the ESC. I have had several occasions when the switch commanded reduced throttle part way through the climb. Getting it away from the ESC solved the problem. At the ASA contest, several pilots experienced the same issue (low or no throttle after a few seconds of motor run) and those also seemed to be related to ESC proximity. This error has been reported to the supplier. With this one exception, the BASIC is an otherwise fine tool.

Shread-RC – The altitude and time cross checks to my RAMs showed the clock to be spot-on but the cutoffs to be high. Although within the 20m limit for the task, the result was systematically high as compared to the other 2 units and the RAMs. This may be a prototype issue with mine and it has been reported to the US supplier. In all other respects this is a very nice unit and the lightest of the three (if you’re worried about 2g on a 700g plane). The jumpers work as advertised and provide an easily modified altitude change at the field. I personally prefer a reset option for the switch without power cycling (for fun-flying and practice) but for contest work that is not an issue. An audible indication for the jumper setting would be convenient. I’ve got ~ 20 flights on the Shread and have not found any interference problems by placing it near the ESC or motor.

- Dave R
Oct 31, 2010, 07:59 AM
Registered User
R.M. Gellart's Avatar
Appreciate the info, Jerry Shape and I were talking doing some bagging last evening at dinner. Maybe around Super V 100 or 1000 fuses, you have us thinking...

Oct 31, 2010, 08:03 AM
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Great stuff Dave. Nice work, and thank you.

Oct 31, 2010, 08:52 AM
mostly gliders
liukku's Avatar

Good job!

Hello Dave

Good job, well done.

I would like to add the RC HLS #1 (Height Limited Switch) to the list of limiter´s.
Perhaps you can also buy it in the U.S.

Oct 31, 2010, 09:14 AM
AMA 7224
Leadchucker's Avatar
Nice job Dave!!!
Oct 31, 2010, 09:58 AM
One of the things that I have observed in the two contests I attended and a couple of tests with ORF's at our field is that this is a event that kind of levels the playing field when it comes to planes. I am sure there will be conditions where one or the other size/design of plane will overshadow others, but so far that has not happened. It is kind of hard to "out launch" another ship so depending on conditions it does not seem so important to have size classes.

More contests will be needed to see what other little differences a "winch in the nose" show up with respect to ground based winches.

I am with Dave that this forum can help with providing dataon which to base future decisions.

Jack Iafret
Oct 31, 2010, 10:10 AM
Dave Register
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Thank you for the feedback. Hopefully the pilots that have flown in the US this season will contribute as this goes along. There are a lot of different ideas about good plane, motor and radio combinations. I hope this forum will address some of those. One of the issues that many of us have who are coming from the TD or discus side is how to evaluate and select the power plant (motor, prop, ESC, battery). Some of that's been done already and can provide a starting point for guys just coming into this area (Leadchucker - you did very well with your system at Polecat - I'd say that makes you a qualified contributor - please!).

Marc, re the Super-V platform, that could make a great e-conversion. It's worked for Supra's and AVA's and my Thermal Dancer. Could be a nice project. The old LeVoe designs were terrific. I still have one of Mark's first designs down in the basment - the Albatross. Craig Foxgord and some of us Rose Bowl guys had a great run in SC2 with that one - one of Mark's first real TD 'floater' designs.

'LIUKKU', thank you for the reference to the new switch. There is a lot of rapid development in this arena. I haven't seen one of these flying in the US (yet) but it offers another option for folks to fly. My list is not meant to be exclusive but tried to include the options that are commercially available in the US - or to US pilots via internet sites. Thanks for this update.

If an item is being sold commercially then comments on performance from users should be available to the buying community. If it's still being prototyped with the vendor then I would hope folks would provide their feedback directly to that vendor until it goes commercial.

Later today I hope to put together some observations on planes that have been flying in competition in the US this year. Need a lot of help on that one - ALES pilots, prepare to describe your planes!


- Dave R
Oct 31, 2010, 10:14 AM
tender's Avatar
Originally Posted by okiesoar
....a World Championship event for altitude limited soaring.
... Our FXJ is an unofficial class, so It can´t be WORLD CHAMPIONSHIPS. It will be only FXJ WORLD CHALLENGE

I think, it will be a good test of the rules with altitude recorders (not altitude switches). Altitude for OFF motor will be variable and result will be "three dimensional" :
starting altitude points + gliding time points + precise landing points.

Last edited by tender; Oct 31, 2010 at 12:00 PM.
Oct 31, 2010, 11:56 AM
Registered User
To Dave aka "okiesoar",

Can you provide please, with some race results with flight time and landing point. Or some statistic's with Flight datas e.t.c.
How many peoples start in 2010 season with HL?
Oct 31, 2010, 01:15 PM
Dave Register
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Originally Posted by tender
... Our FXJ is an unofficial class, so It can´t be WORLD CHAMPIONSHIPS. It will be only FXJ WORLD CHALLENGE
Oops, sorry. My mistake. It's a great idea - good luck with it.

Originally Posted by tender
... I think, it will be a good test of the rules with altitude recorders (not altitude switches). Altitude for OFF motor will be variable and result will be "three dimensional" :
starting altitude points + gliding time points + precise landing points.

As stated at the opening of this thread, this one is not intended to be a rules forum. That's covered in several other discussions. This discussion is to provide an overview and assistance with equipment, schedules, etc to US pilots that are curious about the event. The issues you describe are well covered here:

Originally Posted by Golikov
To Dave aka "okiesoar",

Can you provide please, with some race results with flight time and landing point. Or some statistic's with Flight datas e.t.c.
How many peoples start in 2010 season with HL?
Those are all covered in the respective web sites referenced in the third post (times, scores, # of entries, etc.). Please see those sites for additional information.

This is not a moderated forum so I trust to the participants to keep it to the original intent.

Thanks very much,
- Dave R

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