Hi. My name is David Beach and I'll be the CD for the NATS XC event in 2013. We have a practice day on Friday, June 28th, 2013. The competition is Saturday and Sunday.

The question was asked in that thread:

Originally Posted by rcbrust

David/Group,

Do you think that electric launch sailplanes will ever be allowed for the Nats XC competition, either flown along with the winch launch ships or as their own separate class?

I have a couple 4m Hyper e-AVAs that I'd love to give it a try with someday. I know they're not the ideal XC ship, but it would still be interesting to give it a shot.

Randy

I'm trying to gauge the level of interest in ALES XC competition. Personally, I love XC and the more sailplanes in the air on the course the better as far as I'm concerned. I don't know how the other competitors feel about the issue and didn't want to bring it up on that forum if there wasn't some fairly strong interest from current ALES fliers.

Who's interested?

Who's willing to help?

David

This concept may not really be an ALES event (Altitude Limited) but simply an e-launch sailplane category within XC. Or perhaps there does not need to be any distinction at all.

XC ships are allowed unlimited launches before heading out on the course. I'm not sure there's a difference between that and an electric launch as long as no re-start of the motor is allowed while on the course.

One of the performance trade-offs is likely that the e-launch ship will be heavier. Consequently I would speculate that e-launch XC ships might tend to keep the power and batteries a bit lower than current ALES competition planes. Also, e-launch will have slightly more drag due to the prop. Conversely, the e-launch plane MIGHT be able to make a higher initial launch - which could be addressed with a limiter function. However, a higher launch might get planes on the course sooner which might speed things up a bit.

As long as the plane is not allowed to re-start the motor on the course, I don't see much of a difference. e-launch is definitely lower overhead in launch equipment. Actually, the plane could be launched with the pilot in the bed of the truck - saving on shins and stumbles and other safety issues.

An idea worth trying. After all, we did DLG XC one year at the NATS. Put that little plane up there with the big boys, got through the cemetery, around the corn field and just about to the corner before Ed center-punched a pole. Still, 3+ miles on the old NATS XC course for a DLG remains a record for that class at Muncie. It would be fun to try it with an ALES-type plane.

- Dave R

I agree with Dave. This might be a great event -- and being able to launch out of the back of a truck, changes the logistics significantly. Zero flight for off-field is good. It still leaves the option of a motor-on "save" possible.

As to weight, I'm flying a plane for ALES and F5J that weighs (within an ounce or so) the same as its TD equivalent (a Maxa). Its more likely than not that, at least on a closed course, this plane would do XC with a bit of ballast anyway. I suspect that minimum weights will not be a distinguishing factor between electric and non-electric planes.

Great idea!!

Happy Landings,

Don

BTW: I believe that if we start moving to a little variety in these electric tasks we will discover some interesting NEW ideas. My Maxa flies with a 4S 850 mah pack. Probably good enough for 400 or 500 meters of total altitude gain. It would be interesting to consider an XC/Energy event where the results are based on measured distance divided by measured watt-minutes of battery power input. Right now this can be easily done in sort of a kludgy fashion with a little $70 Eagle Tree unit plus an LCD readout. (I have actually done it.) If the concept turned out to be interesting, a stand alone unit could work. Just thinkin'

Originally Posted by dharban

Great idea!!
....... I believe that if we start moving to a little variety in these electric tasks we will discover some interesting NEW ideas.

Agreed, great idea and I'd give it go. Why not? I like the idea of the challenge even though I've never did XC before and would have to learn a few things.

Great idea and I've voted. However, in the poll there should be an option that after motor shutdown via either altitude or time that the pilot is unable to restart till after resetting of power to the model. i.e. on the ground.

There is a huge difference if you know you can save the model as you'll be more apt to range farther out in the search for lift than with a model with no motor in the nose.

I think as a beginner fun type task, then to me it makes no difference; but for fair competition against non-motorized sailplanes it's a big difference.

Curtis
Montana

After a little off-line discussion, I'm gonna revise my previous comments just a tad.

- I'd agree that after the launch (single, continuous motor run), the motor cannot be re-started without scratching that attempt (0 pts/ 0 distance).

- That would apply any time after the launch motor run is completed - whether during the initial search for a thermal or at any time on the course.

- The launch would be consistent with the current e-launch limiters: 200m or 30s motor run, whichever comes first.

The 200m limit (660ft) would make the launch roughly consistent with a decent winch launch (specific altitude number might need to be discussed but 200m is a starting point). 30s is to keep from ranging all over the field during the launch. The thought being to make e-launch roughly comparable to a winch launch. After that it's the same event.

I'd like to see an emergency motor re-start allowed. These planes are expensive and landing in someone's pasture (or roof-top) could be hazardous to all concerned. Stuck in a tree overnight with LiPo's winding down is an accident waiting to happen. Consistent with the first suggestion (above), you can save the plane but you lose that attempt.

Interesting idea and would be fun.

- Dave R

+1 Dave

I know that there is a temptation to start this thing out as a head-to-head competition with the conventional (if there is such a plane) XC planes. I am not sure what would be demonstrated here. Even conventional XC consists of special, purpose built planes (which are usually BIG) and regular TD planes. So we go from apples and oranges to apples, oranges and apricots.

It seems to me that keeping things as simple as possible and recognizing, at least for now that an ALES plane is not a TD/XC plane. It would surely be useful to start everybody together, just to see what happens. But notwithstanding the "Gordy school of thought" that it isn't really sailplane competition if you can have a restart "save" for no points, I share Dave's view that it is sort of silly to require a plane with a perfectly good motor in the nose be flown to destruction just to prove that point. If we want today's fighter pilots to measure up to our fathers, let's junk the ejection seats and give them a real incentive to get the plane home.

Anyway, if there is enough interest to get this off the ground (sorry, I couldn't resist ) keep it simple AND USER FRIENDLY. Unlike current XC flying, it might even lend itself to being blended in as one task in a broader competition. Launch the last flight of the day and see who can land closest to the tavern. ALES flying has changed the logistics of TD competition as a consequence of its expansion of the range of viable flying sites. It may be that XC ALES will have have some unexpected (and good) logistic consequences too.

Happy Landings,

Don

BTW: This might be a great time in the development of electric comps to start with something like this. We are likely months or at the worst a few years away from telemetry technology which will change the landscape of XC and/or closed course flying. There is already some stuff out there being used in Europe. Right now, it is a little pricey and a little complex. But there is no doubt that it will evolve. And then we will be freed from the launch-count to 600-land syndrome.

I used to fly CC many years ago and did enjoy it other than the 80mph down a dirt road in the back of a pickup. I would keep the E-Launch as close to W-Launch as possible and hopefully after a trial or two, they could be flown together.

I was part of the a team a few years ago at the NATs (old course) and had fun and can not for any reason see the difference in launch method being an issue if done correctly.

I would use the 200M, 30 second rule to start with for the first couple of trial events and then decide if changes need to be made.

Jack

I too think that XC using an ALES platform has a lot of promise and possibility. I agree with the vote taken above, it is a one shot deal after the launch if you want a score and it is pretty simple past that issue, it is just XC. I hear what guys are saying about the emergncy situation, but I have yet to see in many years of being around the XC at the Nats, a ship left on a house or such overnight (a couple left in fields, or air destroyed maybe).

The part that I think that folks that are flying ALES need to keep in mind, ALES is a launch method, not a contest in reality. ALES could be flown as F3B, TD and XC. I view it as a standardized launching system and I hope that guys stop thinking that ALES is only a single contest. There are so many directions to go with this in time, do not get hung restricting ALES to only one dimension of competition.

Marc

Maybe its time to resurrect a concept plane I built for a gentleman in Arkansas a number of years ago, which was also published in S&E Modeler. He wanted an e-launch SBXC. It used a big, geared Hacker motor, 20" folding prop, and a bunch of NiCds. I built and test flew it for him, launching both by hand toss (with help) and off a dolly (for solo launches). At that time it was powered by a brick of NiCd's, somewhere around 20+. All up weight was around 15#. With modern LiPo's this plane could easily come in under FAI legal weights. Hmm...

For any of the ALES pilots who are unfamiliar with XC, here are some resources. The last two articles are written from a newcomer’s perspective, mine.

www.xcsoaring.com - a website dedicated to XC soaring
www.rcgroups.com/cross-country-soaring-684/ - RCGroups’ XC forum
www.rcsoaring.com/rcsd/RCSD-2011-12.pdf - Intro article about XC
The February 2013 issue of Model Airplane News

Video from this year's XC event in Montague

The Full Montague (3 min 0 sec)

One benefit of eXC would be the ability to safely fly courses where landing areas are few or far between. Long stretches of orchard come to mind, or a subdivision built in the middle of an otherwise great course.

JT, if you have photos or links to your e-sbxc, I'd love to see them. I just converted an old Zagi from NiCd to LiPo and shaved half of the battery weight, so hitting the 5Kg (176 Oz.) limit should be very doable.

Thanks for posting Aric.

Marc

"ALES" is really just another launch method ... more people are coming around to that way of thinking.

Progress ...

How about thinking a little different and add efficiency to eXC? In my opinion thinking of a electric motor as a "winch in the nose" is not taking advantage of the interesting options it offers.

Here is one possible idea that could be fun--using the same logging devices that are being used for F5B gliders, measure the total electrical energy used to complete the task.Using energy and time combined to determine the score would make for a interesting event. In addition landing off field would be unnecessary since the motor could be restarted to get out of a bad situation making more areas available to eXC than are to winch launched planes.

The energy information can be easily read from the onboard logging device or can also be sent down to the ground by telemetry using the data link built in to newer radios or by a separate transmitter. I have been flying such a device for nearly a year in my F5B glider and it works fine. In the stand alone version only 2 connections are needed to the power leads between the battery and controller.

Electric power could open up eXC to other planes that would not normally be considered a XC suitable. Smaller planes like the Aspire and other F3J planes could be pressed into use by those wanting to give XC a try.

Steve Neu

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