Eric,

Great news. Your the first to fly a profile electric, good job. Sounds like its working very well especially since it was a first attempt. It will be interesting to see how the high speed develops. I think with some experiments with props you'll be able to increase the top end some. My expectations are to get above 90 mph in high speed with electrics. I think it will really be a challenge to go much better than that. As there are more planes/motor combination flown that will help.

You can see how the electric is nice in low speed. Very controlable. What size is your battery? Did you get a chance for a full low speed flight? Part of the challenge here is hauling enough battery to last through a full hi/low and landing.

The costs should come down, of that I am certain. Electrics do have some up front costs like charger and balancer that add to the initial outlay but once you have them your set for a long time. Also realize there is no fuel costs for a large number of flights.  I think it is not out of the question to get a motor/ESC/battery for under $200 maybe even less. It will take some experience to know how to spec out the system.

I am going to convert my first Vampire to electric and see how that works. I have all the components just need to put in a little assembly time. I'm anxious to get it done.

I think its great you got in some flights and are pleased with the initial results. Keep us posted.

Bob

     About cost, I hear or read that these hi-performance batteries can be recharged around 200 times before they start loosing there luster. That equates to a little over a dollar a flight so hope these batteries come down pretty soon. Thunder power just came out with some newer HP batteries and the price is higher and the shapes are a little different so they may not fit in this plane. This electric stuff is like the computers, by the time you get it home and up and working there is a newer better one out. Oh well, eric

Way to go, Eric - this is great results.  About the cost - even if your glow fuel costs $20/gal, at say 8 oz. per flight (?? - my flights are well under 6 oz., but I don't go very fast or very slow) - that's still over $1/flight.  The batteries don't sound all that bad to me.

Mike

     Mike you better hope the EPA doesn't hear about your lousy milage. My heavy case Nelsons use around 4.5 to 5oz of GMA10/22 per flight. It cost me 15.99+tax here in NV so I'm figuring around $.65 a flight. Really I think the case could be made for either type of power depending on how experienced the case makers were.

Well, I'm still flying my old K&B 5.8 - to get to 90 mph requires 65% at (insert figure here ... $50 ??) - but I've not flown much lately, and was going by what I paid for my last gallon of Sig Racing (35%) -- 18.99 plust tax.  As  far as  quantity - like I said, I use less than 6 oz., say 5, for a 85 mph high and maybe 3 minute low.  I know that Pete, Bill and Art have larger tanks than me, but I don't know what their actual usage is.

I'll agree with you 100% on the "pleasant factor" of flying an electric - especially when you get to turning some decent slow laps.  There is also the factor of being able to walk the plane out onto the circle, stroll to the handle and fly off - no hassle, no flipping, no electric starter, no burned out glow plugs.  Last summer, I had finally got a motor that ran well in a plane that was flying well - I was turning 35 second laps or so and carrying on a conversation with my flying buddy.  When I landed, the "peanut gallery" of spectators gave me a round of applause !!  We almost always attract a few spectators, but I'd never heard them applaud for any kind of flight before.  As for available power, well, we will just have to see on that.  If there is anyway to harness some of the two kilowatt systems and turn that into speed, rather than low-end thrust, then I'm betting that someone will find it.  But probably not me -

Mike A

The other possibility to consider is that if you have one or two "contest" batteries and do your practice flying with the el-cheapo's, used, and ebay specials, your contest packs will probably last for years, if stored properly.  You can pick up really inexpensive packs on RCGroups Want Ad's, IF you are quick on the reply button.  And a $25 battery only has to give you a couple dozen flights/bench runs to be a break even deal.  You can take packs apart when one or two cells start to go over the hill, and combine them with the good cell from other packs.  Costwise, I can't complain too much about the price of battery packs, given my rather sport-oriented outlook the last few years.  I'd only caution that even junk packs need to be handled, stored and disposed of properly.

Mike@

     I think Bob Frogner is putting together a spread sheet on the current e-carrier planes that are flying. He will list all of the equipment we are currently using. I think I copied your set up that you use in Skyray or at least thats what I thought I copied.
     I'm still differing with the committee on whether e-carrier and ic-carrier can be combined. The rules for e-carrier are based on weight (at least for now) and the rules for ic-carrier are based on size of engine. So the e-carrier guys can use bigger and bigger motors as long as they don't go over there weight limit. So do we do the same with ic-carrier and go by weight??? One or the other will have the upper hand by any rule you want to come up with. There is no way to make them equal with rules. When I look at CL-2 and think about your setup for that event there is no way a slower plane could make up in scoring by flying a good LS because you are pretty much the king of speed and also almost unstopable in your LS scores.
     Besides one of the things I like about e-carrier is that it is a slower event than the current AMA events and my old body can keep up. Remember Pete 15 or 20 years from now you will be in my boat withing you had a smaller oar. I'm going to drag my e-plane around to all the contest I fly in this year so I can demo it if possible. eric

Matching gas and electric is not easy. We took a guess at what might work by choosing total weight as a limiting factor for electrics. Putting on an electric motor big enough to get the same power as my Class 2 engine would be so heavy that you would have to cut the battery weight way back to meet the weight limit, and then you would not make it through a long low speed. Again, this was all a guess based on limited experience. Now we'll see what we can really do as people try it. I don't think I can beat my own gas Class 2 with an electric, but I might be able to beat a lot of other peoples' Class 2's and still come out on top with an electric Class 2. Eric, you are absolutely correct that we can't make gas and electric equal, but we might make them close enough that it is other features (quality of model, skill of pilot, luck, etc.) that will dominate in the determination of the winner.
Dave's idea sounds straightforward, and we did discuss power ratings in working out the rules to try. But this is really tough to do in practical terms, and adds a complexity to operating a contest that might cause CD's to just kiss off the electric events. Consider the complications, for example, of measuring power. A gas engine unloads in the air and, when set up just right, gets a significant power increase at speed. An electric has a  higer power output on the ground, and reduces power output as it gets up to speed. In both cases, power output depends on all sorts of stuff, particularly prop selection. (We also considered "manufacturers ratings" of power output and concluded, even if the manufacturers data sheets didn't lie, a big "if", the other variables of prop and battery would complicate things hopelessly.) So we ended up with the rather simple method of total weight as the easiest and, possibly, best way of setting class size, and we hoped the weights chosen will eventually get power outputs close enough to let other factors become more important. Other things one could do, for example, without making things too complicated, include limiting the weight of the motor (or, more precisely as a power limiter, limit the weight of the magnets in the motor.) This is possible, but let's try the simplest things first and see how that works.

Pete

   Matching gas and electric is not easy. .......Pete

I remember a conversation that took place about a year ago on this subject ....

Me ..  "After all, watts is watts."

Pete .. "Not really .... "

How true.

Mike@

     I was finally able to get a couple of flights in with the 109T. The weather was 50 degrees with a very shifty breeze of 4 to 7 mph (estimated) bright sun shine and if you could get out of the breeze the sun felt nice and warm.
     I now have 2 Thunder Power 4500 mAh/14.8v batteries and was able to fly both of them. I think I'm changing my mind on this plane being a little tail heavy and causing it to hunt on the HS portion of the flight. I think it may be the plane (no the pilot isn't taking the, yet) as I have had the same problem with the .15 version of the 109T. Don't know why and have tried quite a few things to no avail so far. This time I'm installing a small flap on each wing panel to see if I can change the aero dynamics enough to get rid of the hunt.
     On the first flight I was into the hunt on the first quarter of the first lap but was able to keep the throttle wide open for the full seven laps, and it was real ugly. The timed HS was 72.22mph and the LS was 3 min. 22 sec.. The plane was flying anywhere from a foot off the ground to a 45 degree angle on the HS portion.
     On the second flight I got around 2.5 laps in before the hunting started so the HS time a little better at 78.57 mph with a low speed time of 3 min. 37 sec.. If I could get this plane to groove I'm sure it would be in the low 80 mph bracket.
     I measured the temperature of the motor at 100 to 105 degrees, the battery at 94 to 96 degrees, and the ESC at 87 to 91 degrees. When I got home and charged the batteries they each took 3000 mAh to bring them back up to 95% at 4.20v. When I measured the voltage just before the charge the batteries were at 3.7v.
     If the weather holds I'll try to get in 2 more flights tomorrow with the flaps on the wing and see if it does anything about getting rid of the hunt. eric

     Well I got two more flights up today. The small flaps seem to have altered the flight characteristics enough so I was able to get two good HS flights. Only trouble was on the first one I forgot to count so no HS time on that one. The LS time was 4 min. flat.
     On the second flight the HS was 81.45 mph which is what I thought I could get with this set up. Only trouble is the motor temperature was taken at the time the plane landed and it was 161 degrees which is 30 degrees over what is safe to run on these motors. The ESC ran 98 degrees and the battery's ran 105 degrees.
     I kind of thought that 11/8 Graupner was a lot of prop for the motor so will try a APC 10/7 next time and then a 9/7 Graupner and see if I can bring the motor temperature down to 130 degrees. Thats after I do a static run to see if the motor was damaged by the high temperatures of the previous runs. eric

For my Skyray, using the same motor and a 4S battery, I found an 11-8 prop was too much (not a Graupner, though) but a 10-8 would draw the maximum current I wanted, somewhere around 50 A in flight. I measure current with a shunt I got from FMA Direct as the "precision measurement." This is probably as good as the digital voltmeter I am using, which might be a few percent. For in-flight measurements, I have used an Eagletree datalogger. It seems to read a bit off from the shunt, so you need to correct the reading. (There is a way to do that within the Eagletree system.) But the important thing to note is that the current drops nearly 10% after takeoff, so measuring on-the-ground current with a shunt is a good guide to in-flight current at a much lower invested cost.
I also found a strange resonance with the 10-7 and 10-8 APC pusher props, usually just below full RPM. The system would get quite loud. Most days, I would get above the resonant RPM in high speed, and would stay below it on low speed. If it was a day when things were not going well, I would run through high speed on resonance, and things would shake a lot, and the speed was maybe a second or so slower than normal. I still have not understood this, and hope to learn more about it during the coming flying season. Could be entirely mechanical in my motor mount system, as Bill Calkins suspects, but I am looking toward something a little stranger in the electrical setup. Maybe we'll learn something from the experts at Toledo.
Pete

I have been using a 1/2" square pot with an 1/8" shaft that I buy from Mouser Electronics as part number 549-149-1503. Delivery has been just a few days. Search www.mouser.com for that part number or try: 
http://www.mouser.com/Search/Refine.aspx?Ntt=*5941491503*&N=1323038&Ntx=mode%2bmatchall&Ns=P_SField&OriginalKeyword=594-149-1503&Ntk=Mouser_Wildcards
The price has jumped around a bit, from $8 to $10.25, so it is slightly more expensive. I use 50K and have an arm long enough to just get the travel I need for the Clancy unit. These pots are pretty small, way smaller than the round ones from Clancy, so they are a lot easier to mount in a protected location. I have not broken one yet, but Bill Calkins lost one when a line broke during a pull test. Pretty much anything can break in a control system when that happens.
A note on the APC pusher props: They are designed to be put onto a pusher setup, not a tractor setup, and the hub is molded with that in mind. I  tried it with a rather small drive washer setup I had with my motor and it comes loose. I bought a new, large diameter collet drive unit from Tower
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXMWK8&P=M and it distributed the force properly over the prop hub and didn't come loose again. It is aluminum and the collet wears and needs to be replaced occasionally, though.
Pete

     I got the Medusa Power Analyzer II yesterday and went right to work to get it ready for testing. So this morning I put the battery in the plane and hooked up the analyzer between the battery and the ESC and gave it a go. With the Graupner 11/8P I was able to get 11,700rpm while pulling 69mah. No wonder it was running a little warm. Then I tried the APC 10/7P and got 12,900rpm while pulling 55mah. I don't have a APC10/8P yet so couldn't test that prop which is the one I hope to be able to use eventually. Maybe tomorrow I will get to fly the plane with the 10/7P and be able to compare it to the 11/8P. details to follow, eric

     I think your right Alan. I get this electic stuff kind of mixed up (all the time). In my last topic I was mixing up what I used while flying the HS portion of the event (69 amps) to the charging rate I use to replace the the big amps I took out (maybe). Sound better or should I give up? eric

Eric, I want to thank you for the info you are putting out on your electric set up.  Seems you are the only one getting any info out other than what Bob Frogner was doing.  You are listing props with dia & pitches like we use on Class II airplanes.   What would happen if you were using the same props you use on your nitro powered planes?  I know that electric will have it over nitro when all is ironed out in that all you do is charge the battery and go.  I did have some consistency when I was flying carrier all the time with the old Merco .49 and McCoy .60 Red Head.  Also I hate to think how much you have invested in this electric stuff, but, is there a package an individual buy in total and go flying?  Anyway keep up the great work.  DOC Holliday

Eric, I want to thank you for the info you are putting out on your electric set up.  Seems you are the only one getting any info out other than what Bob Frogner was doing.  You are listing props with dia & pitches like we use on Class II airplanes.   What would happen if you were using the same props you use on your nitro powered planes?  I know that electric will have it over nitro when all is ironed out in that all you do is charge the battery and go.  I did have some consistency when I was flying carrier all the time with the old Merco .49 and McCoy .60 Red Head.  Also I hate to think how much you have invested in this electric stuff, but, is there a package an individual buy in total and go flying?  Anyway keep up the great work.  DOC Holliday

Well, since I've been "snow-bound" since last Oct., there hasn't really been anything to report.  I've got some new electrics built over the winter, but they aren't carrier planes nor throttled.

As far as "packages" go, there isn't anything commercial available as a package deal.  However, many of the known electric carrier plane - that includes mine, Bob Frogner's, Pete Mazur's, Eric's and Bill Calkin's has been documented numerous times on this forum and on others.  They all work and the components are available over the counter (except for the Clancy Arnold U-tronics controller) and are not all that expensive.  Think the price of a new Nelson.  On my first plane, I asked Pete Mazur what he used.  He graciously detailed WHAT he was using, WHERE to get it, and HOW MUCH it cost.  Based on this input, I set a budget of getting into the air on $300 or less.  Curt Netcott said he was in for $300 also.  So we set out to build and fly two Electric Skyrays and we did bring them in under budget.  It would have saved some headaches to make the budget $400 and save some of the experimenting I did.  Then you could fly exactly what Pete flies.

As for props - the real problem with trying to make electric carrier planes with components that are optimized for electric RC planes is that the prop sizes that actually work at all are not great for going fast.  They are fine for going very slow in a nose-high attitude, however.  That is what electric 3D RC is all about.  As an example, once I had the Skyray flying on the first motor (never mind that brand name - you've probably never heard of it) I found that I had to really load the motor to get it to fly  very well.  The best "prop" that I found was actually a pair of 10-8's or 11-8's, mounted like a 4-blader.  When we tried to go for RPM, someone asked me to try a 9-9 APC - the motor did actually turn more RPM, but the plane wouldn't even come out of the grass.  Just one more point on the learning curve.  This motor was intended for turning large (like 13-14 inch) props on 3 or 4 cell LiPo packs.

After some teething problems with it, I've finally got the Scorpion (3032-8) flying.  The motor had some design issues which took several trips back and forth to the distributor to get ironed out - in the end, they really have a nice motor with very good quality control.  I'm anxious to get it flown.  I also have an AXI (same model as Pete's).  I've flown it and it would also make a good motor.

All of the above has been listed several times in the various threads.  Bob F. has even gathered most of the data into a spreadsheet and it was available for download or he would send it to anyone who asked, I'm sure.
When the weather cooperates, I'll have more to say on what we learn here.

Mike A.

Greetings to you guys,
I've not met Eric or Mike, (sure would like to), Pete and Bob are friends. I've just got to tell you all thanks for what you're doing here- this thread in particular. Eric is a breath of fresh air around the deck to me, nice planes, well thought out. I'm not going the electric route ( unless forced that direction by noise restraints, etc), but it is really fascinating. You guys are pioneers, for sure.

One note, Eric, on the hunting in High Speed, I would consider some down thrust in the motor, (I always call them motors, now they really are!). Perhaps just a few degrees would tame the pitch problem in HS and not too adversely affect the Slow.

And there is another tweak. Kelly Hite, Ely winner, had this problem and Billy B and he solved it with a pushrod/elevator adjustment. I think it was written in a NCS Newsletter article, "How Kelly Got His Groove Back".

I'm a little late here, hopefully it's all trimmed now.

Best regards,
dale gleason