Li Poly batteries, fantastic

Unless I'm confusing my acronyms, They're not EDF, DC3's were prop planes... I don't know if the lower voltage would be adequate for flight speed.

PCPhill

Reply to
PCPhill
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TNP,

The DC-3 never had EDF/Electric Ducted Fan engines & this Electrifly doesn't either. Not race 400's either.

As my original post stated, that DC-3 twin 400 requires 9.6volt, so a

2s2p @ 7.4volt probably wouldn't get it airborne. --

Jim L.

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Reply to
Jim Lilly

Paul,

Not very accurate. Most entry level EP's are as you say, except some like the Aerobird Challenger.

You can get a HobbyZone Aerobird Challenger for around $150.00 which includes EVERYTHING needed to get started & is far more durable & forgiving than most glow trainers. I fly mine when some glow's think it's too windy & fail to show up at the field. The ABC even comes with 2 flight modes, so beginners & advanced pilots can have fun with them. Put in the optional 7 cell/900 mAh battery pack ($30.00 avg) & it screams! --

Jim L.

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Reply to
Jim Lilly

PCPhill,

I doubt it myself. --

Jim L.

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Reply to
Jim Lilly

PCPhill,

I've got an Astro Flight Super Whatt-Meter coming soon, and will be able to determine the DC-3's needs exactly. Still, I need some sort of battery pack as it comes with none. Might throw something NiMh for temp use to determine it's true needs. --

Jim L.

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Reply to
Jim Lilly

Lighter weight, so it might.

If its geared props, go 3s2p and drop the prop diameter an inch roughly

If its DD use same props, 3s2p and get 7.2v motors.

Reply to
The Natural Philosopher

That's good. A mixture of theory and Whatmeter tests show that the 6v speed 400 actually produces less power as the current goes up above 10A. So don't prop or more than that. the 7.2v motor is happier at only 8A.

If you have gears, you can get more out of a 6v 400 at 7-8A and 3s LIPO than 10A at 8 cell levels, because at the lower current is more eficient, and the extra volts gets the power input back.

Props that are 'in the zone' on a 6v 400 on 3s LIPO are:

2.33:1 - use 7x5 3:1 - use 8x6 3.5:1 use 9x6 4:1 use 10x7

APC 'E' props tested.

These will all produce decent thrust with adequate pitch speed - suitable for a model weighing up to about 40 oz (twin motors). For a small reduction in power and much better efficiency and cooler motors, throttle back, or use the next size smaller prop.

Pack weight for 3s2p LIPO about 5oz, as compared with 9.6oz of 8x1700 NIMH cells.

Reply to
The Natural Philosopher

Again, I couldnt be happier with my electric Slowstick. Mind you, we are talking about ENTRY level here, although two or more expert pilots with slowsticks and a few 6 foot combat streamers could have hours of fun (i sure do)

- im getting away from the point. Screw the firebirds, they really do look like wal-mart toys. Not that the SS looks beautiful, but at least it is Hobby Grade stuff.

Logically, one would 'enter' the hobby with an inexpensive electric foamie (such as i did) Move on to a bigger/faster/sportier electric OR a .40 trainer plane, depending on outside factors like your proximity to a club, LHS stock, luck with the electrics, etc. From there, you can either go with an even bigger electric, or a sportier glow plane - this is where the cost of electric really starts getting silly.

Ive learned so much about handling a plane in a few short months with the SS - i couldnt imagine trying to learn the 'old-fashioned' way with a balsa/glow trainer from the start. I did, however, just apply to the AMA, and im looking for a local club. Hopefully, i can hook up with somebody there who can help me learn to fly this old Eaglet that was donated to me. It should be easy to get used to, but i dont wanna take a chance with crashing a balsa/glow plane first time out. Mike

Reply to
MikeF

The,

Doesn't come that way, just DD. But if I ever went to a geared setup, it would need to be planetary as the twin 400's are mounted to the wing's LE & enclosed in cowling. That, or go brushless.

Any easy way to determine which these 400's are?

Did you use Moto-Calc to get those figures?

It's around 3 pounds!

SPECS: Wingspan: 59.4" (1510mm) Wing Area: 393 sq in (25.3sq dm) Weight: 3lb (1360 kg) Wing Loading 17.6 oz/sq ft (53.7g/sq dm) Length: 37" (940mm) Airfoil: fully symmetrical, low wing --

Jim L.

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Reply to
Jim Lilly

Reply to
Paul McIntosh

Reply to
Paul McIntosh

Like TNP, you are comparing apples to oranges. The entry fee I was talking about is not entry LEVEL.

Reply to
Paul McIntosh

Reading what you gentlemen have said, I believe my point about the cost of electric flight is do-able now has been validified. I have two E3Ds. Cost of the first kit From Gary Wright was $100 + the cost of covering, glue, etc. about $50. The second is a copy and materials cost about the same as the kit. Now the AXI brushless, $97, ESP $107 and Li Poly 3S2P cost $100. So the first plane ready to fly costs about $450.

This is a plane capable of verticals and 3D as the name implies. With Li Poly batteries, the flight times will be about 20 minutes, depending on throttle. Longer if the plane just loafs around. The second plane costing about the same will need only the same battery so it would cost about $350 RTF.

I cut down the weight of my field box for glow from about 40 lbs, to about 2 lbs for electric. I just shut off my electric and go home. I do understand some flyers love to tinker with the gooey, oily mess but there's no beating turning on and turning off convenience of electrics. Remember for electric, the charger + power supply for the batteries cost about $200 or less. Is this not a one time cost?

And how much for starter and battery, fuel pump, glow igniter, extra glow plugs, etc. cost for glow planes?

Would someone do a cost analysis on a gas powered plane RTF for comparison?

Sorry for being long winded, just enthused.

Wan

Reply to
Wan

Paul,

That's the whole point here, entry level costs of glow vs electric.

This time you're off base, as my comparison *IS* entry level. No two ways about it. My example comes complete & includes everything needed to get airborne. A simple head to head comparison of what it takes to start in EP. --

Jim L.

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Reply to
Jim Lilly

Wan,

Sure will!

LXCXF442 Tower Hobbies Tower Trainer 40 RTF 42 72630 $269.99 {Complete RTF w/.46 eng, radio, and batteries}

TH3755 Great Planes Standard ProGlo Starter w/Meter & Charger $19.99

TY5871 Great Planes Filling Station Can Fitting Set $4.69

LXK129 Great Planes Silicone Fuel Tubing Standard 3' $2.19

LXMA93 Hobbico Hand Crank Fuel Pump $12.99

LXK134 Great Planes Ultra Precision Fuel Filter $2.99

WS3710 Tower Hobbies Tower Power Starter 12V Deluxe $17.99

{Following 2 items ONLY included as they lowered the overall cost}

DS80011 Tower Hobbies #1 Tower SS Club Pack-C $14.99

PC7125 $25 Promotional Discount $25.00-

*FREE shipping*

Purchased locally; 1 gal 10% glow fuel=$14.00

TOTAL=$334.82 w/discounts {Add avg of 30% at LHS}

*NOT* included; 12v. Gel cell battery, power panel, spare props, etc {Windex, paper towels, and such needed for glows}. --

Jim L.

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Reply to
Jim Lilly

| Reading what you gentlemen have said, I believe my point about the | cost of electric flight is do-able now has been validified.

I don't think that anybody here was arguing otherwise.

| I have two E3Ds. Cost of the first kit From Gary Wright was $100 + | the cost of covering, glue, etc. about $50. The second is a copy and | materials cost about the same as the kit. Now the AXI brushless, | $97, ESP $107 and Li Poly 3S2P cost $100. So the first plane ready | to fly costs about $450.

Doesn't it have a radio and servos?

I don't know what plane you've got, but I imagine it's a smaller plane. This is definately the range where electrics are reasonably priced.

Try to get a 0.60 sized or larger plane with similar performance and see how much it costs -- it'll be quite a bit more.

| I cut down the weight of my field box for glow from about 40 lbs, to | about 2 lbs for electric. I just shut off my electric and go home.

I don't think anybody here needs to be sold on the advantages of electrics.

| Remember for electric, the charger + power supply for the | batteries cost about $200 or less. Is this not a one time cost?

At least until you find that you need to charge two batteries at once :)

And you can do this much cheaper. GP Triton, $130. 110v -> 12v power supply, use an old AT computer power supply. Cost, free to $20. (For car use, you don't need any power supply.)

| And how much for starter and battery, fuel pump, glow igniter, extra | glow plugs, etc. cost for glow planes?

Well, much of that stuff is optional, especially for a smaller plane. And except for the glow plugs, it's a one time cost just like the charger. At least until it wears out ...

For a small glow plane, a fuel bulb, glow ignitor and wood dowel (for starting) will get you going for about $20. | Would someone do a cost analysis on a gas powered plane RTF for | comparison?

Well, I don't know what your plane is, I'm guessing it's 1/2A sized. So a good engine could be had for $50 or so, and you'll need a throttle servo, about $20 for a mini. $10 for a fuel tank. That, and some fuel replaces your entire $300 power chain. (Though there may be some additional cost as you'll need to make the plane fuel proof.)

This thread wasn't originally about entry level. It was about the extreme cost (compared to glow) of larger electric planes. The entry level glow plane is about 0.40 sized, and the entry level electric is usually 1/2A (0.05 or so) sized. Cost is the primary reason that these sizes are entry level -- anything larger will cost more, but going smaller won't be much (or any) cheaper.

Reply to
Doug McLaren

I agree the initial investment is high. I just spent a small fortune on Kokam 1500 batteries, 8 each 3s and 2s. The primary purpose is for a 1/4 scale with a 10S4P pack. But with the PCBs (series and parallel) they manufacture it will now be a simple matter for me to power anything from a speed 280 up to about a 90 glow equivalent. I haven't flown my glow models for a while now and I'm really considering selling all the engines. If anyone is interested I have a used, good running Saito 1.82 twin 4 Stroke headed to eBay soon.( Gotta pay for the batteries somehow) Make a reasonable offer.....

PCPhill

Reply to
PCPhill

Yes but so do glow powered planes.

Well, Doug, my plane has a 48" wing span and weighs about 56 oz before Li Poly reduced it to about 42 oz. I do have an advantage of lower weight over the heavier glow planes, if you could call it that.

I have a friend who just finished a plane with a motor comparable in power to a .90 four stroke. Yes, his system did cost lots more and I can't account for it. Oh, yes his battery did cost about $345. And he does have a charger that could charge multiple battery packs.

But how much does a .90 four stroke cost?

For me, you're right on that. I have to charge one battery at a time. But it's good for the whole afternoon after that charge. If only I have a charger like my friend's.....

Now you tell me. I think I paid too much for the power supply for my Triton..

Agreed

To do what my plane could, you'd need a .32 to .45 powered glow plane. Case in point, another flyer with a .40 OS could not keep up with it in a chase. Trouble at the time I had only about 7 miniutes flight time, but Li Poly changed that.

My power train, motor, ESC, battery as presented befere, cost about $300. But, no fuel proofing, no tank, no need to buy fuel. But a good .32 engine such as the Webra costs about $109 rather than th $50 or so. But you do have me on the replacement cost.

Yes it was about the cost extremes from the smaller batteries to the nearly $900 batteries. But I know someone who made his own indoor plane of blue foam and flew it, total cost about $72. Now that's cheap. At the other extreme for electrics, the sky's the limit.

I believe we're all waiting for prices of batteries to come down. Now I've heard there will be Li Poly batteries that will yield 20 C. I wonder if that will drive the "old" battery prices down?

Where do you get all your quotes? "Discussion is good for the soul", Wan

Reply to
Wan

I was NOT TALKING ENTRY LEVEL AND NEITHER WAS ANYONE BUT YOU TWO.

When I say entry fee, I mean the cost to get a specific level of airplane to the flying field, in flight ready condition. You guys read something into it that I did not type.

Reply to
Paul McIntosh

DD, for 3s LIPO use teh 7.2v motor.

If not marked, probably 6v motors.

Partly, and partly cross checking with a selection of props and gearboxes. Heck, the weather has been **** and I had little better to do...:-)

I seriously doubt it will fly successfully on two DD 400's then.. Well it WILL, but its a fairly high wing loading and not a great reserve of power.

Don't eliminate gearboxes - the MPjet inner driven ones are very compact.

Also, you can upgrade to 'long can' 400's - and provided the batteries can take the 30A or so the setup will draw, get about 50% more power.

So, stick to stock motors an 1700 NiMh cells. get 7.2v motors and 3s2p LIPO gear existng motors and go 3s2p LIPO

Depending on what suits best.

Reply to
The Natural Philosopher

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