Author Topic: Electric Carrier (Read 3354 times)

bfrog · « **on:** April 01, 2007, 02:37:45 PM »

This forum has been kind of quite lately. Needs some new energy.

How about ELECTRICITY?

??

I just flew my first electric carrier model today. It was an old Sniper, 15 sized carrier plane I had and I modified it for electrics. Its a proof of concept model so its not real pretty and things are attached where I could fit them. The next version will be built with electrics in mind and should be cleaner and lighter.

Here is a link to some pictures:

http://good-times.webshots.com/album/558463249GjpkDE

I only got one flight today due to some teething problems but the results were much better than I expected. Took off easily and flew very well. Air speed was clocked at 66.6 mph with a 10X6 prop. I have a 9X7 prop that should bump the speed up a bit. The plane is a foam wing Sniper. All up weight with battery came in at about 32 oz. I hope to get later versions down below 30 fairly easily. Throttle works smooth with excellent control. For the initial flight I did not have the throttle linkage adjusted quite right so I could not get very low speed so I couldn't hang it. With a small adjustment this should work just fine. I believe that the concept is now proven and further flights should be excellent.

If you have any questions, post them and I will be glad to answer them. I'll also have more details in a later post.

E Carrier lives!!!!

Paul Smith · « **Reply #1 on:** April 01, 2007, 04:11:23 PM »

The concept of electric carrier is interesting.

But, please, start a new evert.

Don't try to hyjack the existing ones.

Electric motors bypass all the challenge of getting a high performance piston engine to work with a throttle. The two just don't mix.

bfrog · « **Reply #2 on:** April 01, 2007, 06:02:23 PM »

The idea here is to start looking toward the future not to eliminate or change the existing events. As flying fields get more restrictive electrics may have to become more of the norm. You can already see a growing trend in stunt to go electric. I posted this because I thought others might be interested. Electrics bring in a different set of challenges that some might find interesting and it also may bring some people who haven't thought about carrier to give it a try.

I disagree that the only challenge is to get a fuel based motor to run with a throttle. There are many more aspects of carrier that pose challenges too.

No, I'm not trying to subvert the current carrier classes but open up some new possibilities. I regularly fly carrier at local and national level events and enjoy the competition. Electrics are just another avenue to explore.

Paul Smith · « **Reply #3 on:** April 01, 2007, 07:33:48 PM »

Typically, events such as speed, racing, carrier, scale, and free flight have successfully added new events without dropping the existing ones.

This allows healthy progress without upsetting the people who have built and grown the events over several decades.

Attempts to electricute and hyjack existing stunt events are another matter entirely.

From my readings, it is obvious that no means is yet available to measure and classifly the potential power of electric systems with the same reliablity as the displacement of a piston engine.

Alan Hahn · « **Reply #4 on:** April 01, 2007, 08:25:49 PM »

I am guessing that electric carrier is already on its way. Listening to how excited Pete Mazur sounds about his Electric Skyray Carrier plane sort of implies that the hearts and minds of the Carrier guys has already changed big time.

Paul Smith · « **Reply #5 on:** April 02, 2007, 04:44:48 AM »

Quote from: Alan Hahn on April 01, 2007, 08:25:49 PM

I am guessing that electric carrier is already on its way. Listening to how excited Pete Mazur sounds about his Electric Skyray Carrier plane sort of implies that the hearts and minds of the Carrier guys has already changed big time.

OK, so how do you prove that the electric system is not more powerful than a .36?

I guess it wouldn't hurt to have Electric Class II, since that event is essentially unlimited (except by total weight) already.

eric conley · « **Reply #6 on:** April 02, 2007, 11:11:39 AM »

Hey Bob this is eric. I have a few questions on your e-carrier ship. Was the almost 67 mph speed from a take-off for 8 laps or was it timed after the plane got up to top speed? The weight seems a bit heavy as I have found that most of my 15 planes come in around 25oz with the MVVS and an empty 4oz metal tank. What is the weight of the motor and battery? I could get interested in e-carrier real easily, keep us posted on your findings. eric

bfrog · « **Reply #7 on:** April 02, 2007, 12:01:05 PM »

Eric,

I was waiting for a comment by you!!

In answer to your questions. That was air speed in flight not from a take off. It was the first flight and I didn't know how it would react to I just had someone time it for a couple of the high speed laps. I was using a 10X6 prop so I think a little smaller prop and more pitch might bring the speed up. The motor is rated at an 11X6 prop!!! One problem I'm finding is getting a selection of reverse rotation electric props. I may try some regular props too. I have a 9X7 Reverse that I will try next flight. One nice thing about electrics is that you can change rotation by just switching 2 wires.

Yes the weight is heavy. This was an old plane I took apart and refinished and fitted the electrics as best I could. If I built a specially built electric plane I would build it differently a save some weight. A few other bits could easily help too. The pot is big and heavy, it doesn't draw much current since it only runs the speed control. I'm going to order some smaller lighter pots. I also kept all the lead lengths for the electrics as they came on the different components since this was a test only. If I cut down the length of all those wires I could save more weight. I used aluminum mounting for a couple of parts too and on a special built plane I would build them into the base structure saving a bit more.

When I rebuilt the old Sniper I probably added some weight too. I had to fix up the wings, add some stiffening to the motor mount and build longer landing gear for the bigger prop. All of that probably added a couple of oz.

I weighed the electrics and if my memory serves me right this is about what they are:

Motor approx 6 oz
Battery approx 6 oz
Speed control 1 1/2 oz

then there is the Clancy Arnold unit but its pretty light and also the pot and the on/off switch.

So figure 15 oz or so for the power system. That's not too much more than a glow engine, and tank full of fuel and I'm sure but the electric motor has lots more torque and swings a bigger prop. I was surprised at the speed as I guessed it wouldn't do more than about 50 mph.

I think there is lots of potential here.

Let me know if you have more questions.

Bob

bfrog · « **Reply #8 on:** April 07, 2007, 06:15:12 PM »

I was able to fly the E Carrier plane again today and had some good results. Since I only have one battery I only got a few short flights in but I learned from them.

I replaced the switch that I had between the utronics controller and the ESC with an arming plug. This a high current plug that is easily connected or pulled out to arm the system. It goes in line with the battery. For flights, the ground person just holds the plane, inserts the arming plug and after the ESC chirps that its ready the plane is set for take off. Works very well. Its a bit bulky on a 15 size plane, I may have to try and come up with a smaller unit for future models.

I used a 9X6 reverse rotation prop this time. Time from launch to 8 laps was 29 seconds or 62 mph. Not too far off the 70 mph max for 15 carrier. After high speed I tried to get it into a hang. Two things made this difficult. The throttle response at mid range was abrupt so when I would get the tail down and then throttle up the transition was too quick. I should be able to fix this with a longer arm on the throttle pot so the travel is longer. That should make the transition smoother. The other issue I had was due to the airplane itself, normal carrier flying. To hang I have to give a lot of up elevator. The elevator needs to be bigger or I need to adjust the pivot on the control horn to give more up control. Nothing new on this airplane.

I flew it once for a full high speed and then a minute or two trying to hang it. Next flight I did get it into a hang but with the throttle response the way it was it was difficult to keep it there for more than a lap or so.
One last flight for some pictures and then the battery ran out of power.

So I'll fix a few bugs and try it again. I believe the basic functions are there and just need to fine tune it further.

I added a couple of new pictures at this website:

http://community.webshots.com/album/558463249GjpkDE

Any questions? let me know.

Bob

eric conley · « **Reply #9 on:** April 07, 2007, 08:11:54 PM »

Very interesting. 29 sec and 62mph is what my old sniper with the OS 21FS( 4cycle) used to turn so me thinks you elect. plane is probably turning around the same RPM. With the 4cycle engine I was limited to 11k at take off I suppose it unloaded to around 12k. I used one of those white plastic Tornado 8/6P and ran between high 28s to low 32s in the HS portion of the flight. I find the 15 carrier planes to be the biggest challenge to fly for some reason. My latest 15 109T has a elevator that is 2 inches wide at the root and tapers all the way down to 1-3/4'' at the tip and spans 14'' or very close to what the 36 planes use. I try very hard to keep them balanced as far back on the wing( tail heavy) as I can and still have control to fly the HS portion. I still end up carrying quite a bit of up elevator to keep it in the hang ( like full up most of the time) and its all a mystery to me why these 15 plane act this way as the profile 36s don't behave this way at all. Do you suppose that the elect. 15 planes could use a box or built up fuselage to hide all those wires. Course the phrase

keep it simple stupid'' does come to mind after the previous sentence. Its looking pretty good so far Bob and please keep us posted. eric

bfrog · « **Reply #10 on:** April 07, 2007, 08:24:11 PM »

Eric,

Yes, I find the 15s to be a challenge too and for some reason they need a lot of up for hanging. I think I can put more weight towards the tail as its still pretty stable in high.

The wires are ugly and on this plane especially so. I didn't trim any of them to fit the plane since this is all an experiment. I can make it much tidier when I feel I have the set up working. It will take off some weight and clean it up a lot.

I was very encouraged today. There is still a lot of work with different props too. I think it will get near 70 when the right setup if found. I have been talking with Pete Mazur and another fellow back east on a alot of this. They are building Skyray sized planes. They should add to the knowledge base too. Its fun and interesting to work with something new. You might want to give it a try!!!!

JimnAZ · « **Reply #11 on:** April 09, 2007, 02:02:29 PM »

Quote from: bfrog on April 07, 2007, 06:15:12 PM

The throttle response at mid range was abrupt so when I would get the tail down and then throttle up the transition was too quick. I should be able to fix this with a longer arm on the throttle pot so the travel is longer. That should make the transition smoother. The other issue I had was due to the airplane itself, normal carrier flying. To hang I have to give a lot of up elevator. The elevator needs to be bigger or I need to adjust the pivot on the control horn to give more up control. Nothing new on this airplane.

I flew it once for a full high speed and then a minute or two trying to hang it. Next flight I did get it into a hang but with the throttle response the way it was it was difficult to keep it there for more than a lap or so.
One last flight for some pictures and then the battery ran out of power.

So I'll fix a few bugs and try it again. I believe the basic functions are there and just need to fine tune it further.

I added a couple of new pictures at this website:

http://community.webshots.com/album/558463249GjpkDE

Any questions? let me know.

Bob

Hi Bob,

Please don't hold my newness to this forum as a weakness. I have been doing electric flying and motor building for the last several years and focused on Helicopters and pattern.

I am also working on E-CL flying and I have been using an Astroflight servo tester(many others on the market) which is very inexpensive and I have connected the third line bellcrank to the pot(part of the servo tester) after taking it out of its case. A much lighter alternative to the system you are using right now. What Axi are you using and ESC? I have been using Castle Creations CC45 and 35 for years and I have found it has a very linear throttle response. Could be something in the geometry of your pot bellcrank.

I am really glad to see Electric power coming now. By the way I started in modelling(CL) way back in the 50's.

Jim

bfrog · « **Reply #12 on:** April 09, 2007, 10:19:42 PM »

Jim,

Thanks for sharing your experience. I had toyed with the idea of a servo driver but the ones I found were just circuits and I thought the Utronics unit was pretty cheap and easy for a start. It does work very well too.

I am using an Axi 2820/8 motor and a Castle Phoenix -60 ESC. I needed the 60 to cover what I expected to be 50 or 55 amps of current. I measured my setup and got 48 amps on the 10X6 prop. I have some other props I want to try too.

I had built a small electric last year, just for fun. 1/2A sized and it flew pretty well. I mainly fly carrier so the next logical step was to try and electrify one of those. There are a couple of others across the country working on E Carrier but from what I have heard, I'm the first one with a plane in the air.

The throttle was linear, just too short coupled I think. I am going to work on the linkage and pivot arm to make it more flyable. Hope to test it out some more this weekend.

I started flying CL in the 60's and then didn't fly it again until about 6 years ago. Did some RC foamy electrics and helicopters in the last few years too. The carrier stuff is really fun and challenging. That's what I like about it. For Nats this year I should have a couple of carrier planes, a nostalgia carrier plane, the E carrier and a Half A profile proto speed plane. Just too many fun toys and so little time!!!!!

bfrog · « **Reply #13 on:** April 11, 2007, 07:05:22 PM »

I added a couple of more pictures here:

http://good-times.webshots.com/album/558463249GjpkDE

I put some markings on the plane so it looks better.

bfrog · « **Reply #14 on:** April 28, 2007, 03:13:57 PM »

Was able to fly the E carrier plane again today with good results. High speed was in the 29 second range. Not great but acceptable. I will try some different prop sizes next.

The problem I had with the throttle being too sensitive was solved with a longer arm on the pot. Response was comparable to a glow powered plane. I was able to hang it without much drama and get some good low speed laps in. The only problem now is the same I had with the plane when it was glow powered. It like to flop on its back going down wind in low speed. I had that happen twice and the second time the motor mount broke. It will be a quick fix but stopped progress for the day. Had pretty good flight time too. I think that the 2300 MAH battery will be sufficient for a full Hi/Lo/Landing of reasonable duration.

More news later.

bfrog · « **Reply #15 on:** May 09, 2007, 09:28:34 PM »

I just added some more pictures to the photo link (listed at the beginning of this thread.

Pictures of Pete Mazur's and Mike Anderson's electric Skyrays.

Mike recently flew one of his planes with very good results. He is using A123 batteries.

Pete just completed his plane and weather has kept him grounded. He hopes to get some flights in soon.

Larry Wong · « **Reply #16 on:** May 13, 2007, 12:41:30 PM »

Bob's carrier plane , he got 2 full flights on one charge....

bfrog · « **Reply #17 on:** May 13, 2007, 06:33:21 PM »

Larry,

Thanks for the photo. It looks great. I did use two different batteries for the two flights though. I haven't recharged them yet so I don't know how much I took out of each one. They had plenty left at the end of some pretty long flights though. First flight was over 5 minutes with a complete hi and low cycle and time left over. 2200 Mah battery on a 10X6 prop.

I posted some further photos on the photo site mentioned earlier.

A couple of the Sniper in the air

A couple of Pete Mazur's electirc Skyray in the air and on the ground.

Good progress this weekend here in California and in Illinois.

john e. holliday · « **Reply #18 on:** May 21, 2007, 09:38:11 PM »

Great to hear you guys are having good results with your E powered planes. So How do you figure what size motor is equal to a certain size engine? Did get to see Pete's plane at the Iowa contest. It had not been flown at that time as the leadouts were not finished. DOC Holliday

bfrog · « **Reply #19 on:** May 21, 2007, 10:02:36 PM »

Doc,

We don't have a formula yet for equivalent glow to electric. That could be a difficult thing to do. At this point we're just trying to get them going.

I sized mine based on the electric motor rating (600 watts) and the fact that the Cox Conquest I use in 15 is rated at about 3/4 hp. One horse power is about 750 watts so I just did the math and found a motor that was close.

bfrog · « **Reply #20 on:** May 28, 2007, 09:19:18 PM »

I added some video of the 15 sized E Carrier plane at the picture site mentioned above. Not great videos but may be of interest to some.

Be patient the videos take a minute or so to download.

Bob

bfrog · « **Reply #21 on:** June 10, 2007, 02:21:40 PM »

Had a chance to take out the 15 E plane today and had some GREAT
results.

I added about 1/2 inch to the elevator so I could get the tail down
into a hang. I also changed to a 10X7 prop. First flight was a 27.1
high speed which I thought was good. Didn't get a low speed time.

For the next flight I tweaked the return tension on the handle so
that it was a bit softer. I have a wire arm mounted to the handle
with a rubber band back to the arm that sticks up from the trigger.
This give positive return to low throttle when the trigger is
released. It had been sticking and hard to move smoothly at hanging
speeds. Reducing the tension made it much smoother at mid range.

Second flight results, 25.6 high speed. That is under the 70 MPH max
for 15 carrier by .1 seconds so I'm as good as I need there. Low
speed with an experienced carrier guy doing the timing was 3 min 4
seconds. Broke the 3 min mark. Good landing right where I wanted it.
Assumming a deck was there it would have been a 240 point flight.
Slight breeze too and the reverse rotation really helped. Good line
tension even cross wind. Could get it to hang for most of the low
speed. No problem flipping on its back down wind. All in all a very
good flight. In fact I think it is better than any of my glow powered
15 carrier flights. The battery was warm but not hot at the end of
the flight. I haven't recharged the battery but there was plenty
left. I did about 5 more laps after the low speed before I landed and
there didn't seem to be any battery sag at the end.

I'm very pleased. The whole setup is working very well. Nice and
smooth at high speed too. I might be able to shift the battery back a
bit more and improve the hang a bit. I think with a bit more practice
I can improve the low speed significantly.

The nice thing is after flying I collect the airplane and there is no
clean up or equipment to deal with. Starting is quick and easy and
with a charge I'm ready for another flight. I did not try the 10X8
prop since the X7 seems to be all I need. Didn't measure current
either but based on expereince and the battery temp after the flight
I'm in good shape.

Hey, this works!!!!!!

Now I need some competition. Who wants to step up? I'll give you all
the help I can based on my experience.

skyshark58 · « **Reply #22 on:** June 10, 2007, 07:54:57 PM »

I assume you are using 52' .012 lines.

bfrog · « **Reply #23 on:** June 10, 2007, 08:03:58 PM »

Skyshark,

Yes, standard 15 carrier gear, lines and line length.

frank carlisle · « **Reply #24 on:** June 18, 2007, 08:17:59 PM »

Don't listen to anyone that argues against electric anything. I've had two electric planes so far and have friends that fly electric. It's the future. Run with it.