kregan

Hi,



I have a question for you electric guys.
I still have my Brio with the 140rx and I have been toying with the idea
of converting it to electric.

I have several 12s1p a123 packs I fly in my Trex 600 and this is what I have
up with. How do you think it would fly ?

-

Brio ready to fly dry = 165oz. Or 10.3 pounds.
Brio ready to fly wet = 187oz. or 11.68 pounds.

Subtract:
fuel and tank – 22oz.
OS 140rx – 30oz.
header, pipe, servo, = 6oz.

Total = 58oz.
58oz – 187oz = 129oz or 8.06 pounds

This includes a fromeco 2400 2 cell rx pack, regulator
and a Hyde mount and nose ring. I don't know what the
difference will be between a Hyde mount and an electric
mount?

-

Electric components:

12s1p a123 = 32oz. X 2 for a 2p config. = 64oz.
Motor Axi 5330/F3A = 23oz.
speed controller = 3oz. ???

129 + 64 + 23 + 3 = 219oz or 13.68 pounds. Two pounds heavier
then the glow setup.


Drive calc comes up with:
22x10 apc @ 5913 rpm
70 amps
2340 watts power in
1840 watts power out

Any thoughts?

woodie

If DriveCalc is correct with the rpm estimate using a 10" pitch, and the plane is 13lb+ you would probably be disappointed in the performance. The plane would be slow and heavy, not a good combination. You might be able to go down in diameter and up in pitch to improve in flight speed but it would still be very heavy.

My E-Brio was just barely over 11lb when finished and I don't think it would have performed well if it were much heavier.

Woodie

Barye

My Feedback: (27)

Try a 21x14 and see what results it shows

kregan

I know the a123's are heavy but I like them.

no 14" pitch props in the calculator...

21x10 apc:
60 amps
6193 rpm
2042 watts in
1650 watts out

kregan

Moving to a 1p setup looks like this...

Electric components:

16s1p a123 = 44oz.
Motor Axi 5330/F3A = 23oz.
speed controller = 3oz. ???

129 + 44 + 23 + 3 = 199oz or 12.43 pounds.

Drive calc comes up with:
19x9 @ 7733 rpm
56 amps
2325 watts power in
19050 watts power out

Anthony-RCU

My Feedback: (2)

A Castle HV 85 is 4.2 oz. As you know a Brio is a very draggy ship and likes power. I don't think you will be very happy with your flight times on a 1p set up. I have flown a Vanquish on 4s and 5s 1p A123 and anything more than 40 amps really kills flight time. A123 are neat but really just too heavy for pattern planes and the imported lipos are cheaper.
I recently pulled my OS 1.40 powered Brio out of moth balls and forgot how well it flies. Considering converting to E power since I have an extra 5330/F3A and HV 85 hanging around. An AXI will not be happy on those big props. The 20 *13 is what they recommend but the 20.5 x 14 flies best.
A few guys in my area did campaign this same set up, with 10s lipos, for a season and where very happy but both ships where under 11 lbs. With the little wings and all the drag of a Brio I would shoot for a lighter set up. You could try ballasting your plane to see how it flies at that weight before tearing everything out.

kregan

Thanks guys...

When I did the math last night I kind of knew the answer, to heavy.
I guess I will keep the 140rx setup.

onewasp

Anthony-RCU

Quote
A123 are neat but really just too heavy for pattern planes and the imported lipos are cheaper.

Quote

I cannot address the Brio set up but as I have been flying A123 5S in the Diamante 25e for two years and I don't think you can begin to compare the price of A123's with LiPos, particularly on a cost/flight basis.
A123's retail @$16.00/cell and it takes but a short time to solder them up 5S including balancing leads..
I recharge in 15 minutes or less, FMA 10S, and with two packs I can stay airborne for most of the day.
A 5S x 2300mah A123 pack is 14oz. AUW.

I usually fly 6 flights (sometimes more) per outing and to date I.E. two years the pack(s) show no measurable decrease in capacity.

I realize the Brio is smaller but the Diamante is a Pattern style airplane with 485 squares. AUW ready to fly is 60 Ozs.
I have also flown the E-flite Extra with 4S A123 x 2300 and it performs very well.
Diamante flight times are from a low of 6 minutes to a high of 8+ depending on style.

The Extra is an easy 8 minutes and you could get to 10 if you try.
Do not forget that you can flatten the A123's with no negative effect on life cycles.
Can't do that with LiPos.

I use CC Phoenix 60's for my ESC with LVC set at 10.0v. soft.

With the LARGE difference in life cycles (favoring the A123's) it is hard to see where LiPos are even close in terms of dollars and cents. I.E. 1000 cycles vs. <200.

I have found the optimal plane size to be 500 to 700 sq. in. for the A123 x 2300 5S packs.

In terms of larger airplanes and *****g on power density the odds shift to LiPos for performance. Witness F3A.
Should A123 introduce larger capacity cells in the near future the size limitation may change.

ExFokkerFlyer

My Feedback: (4)

The Brio is a 2M plane... he's not talking about the Eflite Brio.

onewasp

Ahh so...... That does make a difference [X(].

I've been on the "go small" route for the last few years and my mid set has changed.
2M, there is no viable alternative at the moment.

kregan

What got me thinking about all this was my first attempt at a glow
to electric conversion on the cheap...

Venus 40 - covering stripped to lighten the fuse
Renamed
6s1p a123
turnigy motor
HXT 80 amp speed control
turnigy high voltage BEC

onewasp

You aren't giving the plane even half a chance with your choice of names. [][X(]

kregan

I wanted to name it "Uranus" but didn't have a U and r.

onewasp

An unlikely story .

Jason Arnold

How could you name your model ANUS 40? That's just wrong!!! [&:]

Cheers
Jason.

kregan

Here is the back story

A friend on mine had this plane and kept calling it a pile of @#$% glow plane.
You see he was really getting sick of glow fuel and was also a bit annoyed that
it had a one piece wing.

We decided to do a community plane, he would supply the plane and I would
power it. He kept asking how the pile of #$%^ was coming along so I decided
to name it appropriately.

Now that it flies so nice I might have to rename it. BTW I flew it today on a 7s1p
setup and it is great.

onewasp

MUCH more plausible !

I wouldn't expect your nomenclature to catch on however .

BTW where did you end up on weight with your 'Venanus' (only works on one side)?
Also what motor?

kregan

I started a new thread with pics and graphs for you.