Hi Guys,
This is something i have been thinking a lot about, as i am looking to sometime this year start a large ultimate and cannot decide to go gas or electric.

I though i might solicit advice and comments (constructive) from you guys who have more experience.

From my point of view, i'm eventually looking a a 100cc size ultimate.  If i go gas, then a DLE 111 is probably my choice due to cost.(~$500-550)
If i go electric then a Hacker 100(~$750) is what i have been looking at, with a CC 160 amp ESC(~270).

The cost of the electric setup is higher and then you need to buy at lease 8 6 cell batteries at ~ $75 each for another 300 bucks.

Secondly, there is the issue of flying time....will this setup give me enough time to complete an IMAC routine?

As far as charging goes for batteries, i think im good but could use a second charger...

So, let the discussion begin....

Why should i go one way or the other??

I appreciate your input...

Brian

Obviously electrics have come a long way from the "paint drying" painful flights we saw years ago at Debert... it's almost 10 years since one of the Shulman boys took an electric to the World pattern championships and came third...

Mark can wade in at any time, but we saw some of his flights last year at Truro come a bit shy of time and put him in the crops...big chunkin' packs required... that said, more guys are having great success with electric (in fact most of us have at least one in our basement)

Plane will be heavier, I think, but you'll have tons of tourque.. but then, as Al said, you gotta keep changing those packs..

go fort...

Yes Al, you are right!

I forgot about the extra parts...and i would probably want canisters if i were going gas...and smoke...lol

I'm not sure about the weight question....from everything i have read, the weights seem to come in fairly close.

The advantages of the electric, aside from as Sandy mentioned...gobbs of torque, are from my point of view, the controllability of the throttle on the down rev, and the fact that you don't get a "dead stick" until the end....lol

The big disadvantages are the cost of the batteries and the charge time.

I'm thinking that for IMAC i would need at least two complete sets of batteries, thats two sets of 4x6cells at say $75/battery, or $600 bucks!

I don't think i will know for sure about the flight times until i go fly the pattern.

One other thing i read was that the wind can really affect the flight times.  Flying into the wind simply eats up more power...

I don't notice this on smaller planes, but then again i'm only flying one battery.

Brian

Jon Eastman is also a good resource to tap into. He has been running large electrics for some time. One thing to consider with batteries is to think of them as fuel. They will be a recurring cost, not a one-time cost. They get tired and wear just like any other part. The cannister comment was a good one, as the noise issue is real and not going away at our field at least. the stock mufflers on any of the DLE's or Da's will sit in the box, as they simply are far too loud to use at our field.

Just a though on batteries , did you consider the battery charger and the time it will take you each week to charge the batteries ?

Ben Lann wrote on Feb 6^th, 2013 at 1:04pm:


blah blah blah......... attention hooore is right 

Some great points have been made.  I will add my 2 cents....i mean 5 cents.

That 60 inch electric extra that crashed in the weeds at the Truro IMAC is a pretty good illustration of one of the downfalls of electric.  I blame it solely on myself as I had a cheap HK battery that was too small.  I used a 3300 mah 6S Nano Tech at the Truro IMAC and I flew it at the Avon IMAC with a 3700 Pulse Ultra.  Night and day difference.  Easily getting 9 min flights (can do 2 advanced sequences) and still have great power at the end with the Pulse battery.  A fresh battery is yeilding 285 watter per lb static (probably a little more with the Pulse).  That is silly power.  My 89inch Extra will be pushing 320 watts per lb.  Flight time may be an issue.

That being said, if you want an economical setup, don't even bother with bigger electrics.  As it stands right now a 50cc gas setup versus a equivalent electric setup are not that far apart as far as cost.  To get a gas setup that is comparable powerwise, you are probably looking at DA60 with a tuned pipe and all the associated crap.  Pretty much count on dropping anywhere between 650$ to 1000$ on a gas setup.  My Rimfire 65 that I will be using will spin a 24x12 at around 6000 rpm and draw around 6000 watts.  A piped DA60 might get 4000 watts and the majority of it happens in the high rpm ranges.

For me, the linear throttle response is huge.  Whether i want to fly 3D or precision, it is as linear as it gets.

Like Ben said, charge time can be a killer.  However if you have the proper equipment, it is not an issue unless you want to get 4 or 5 flights in within an hour.  Most of the newer batteries will charge properly in 30 minutes (2C charge rate).  I have a 2000 watt Honda generator, a 12v 60 amp power supply, a 12v 47 amp power supply and 2 dual port 800w chargers with parallel charging boards.  Each power supply was around 50$ and each charger came in around 130$ landed from HK.  Not cheap but not crazy expensive either.  My chargers are capable of charging 4 6S lipos at 16 amps each..all at the same time.  That would be 4 6S 8000mah lipo's charged in 30 minutes all at the same time. My power supplies are not up to that task but I may upgrade in the future if need be.  For now, my el cheapo supplies are fine.  With this charging power, I will be running only 1 set of batteries.  For me, I like to fly and then sit back, relax and join in the peanut gallery to make fun of Whitelaw's various airframes.

I am going all electric because it is something somewhat different and we are all going to be flying electric sooner than later...it is just a matter of time.  Once we see another leap forward in battery technology, it will all but kill IC in the generic sport models that we fly 95% of the time. 

Hi Ben, Mark,

I already have a generator and 4 x 6 cell batteries to run in the Yak.  I think i will pick up a larger DC charger that can do 2 x 6 cells at the same time. I also have a large deep cell battery that i got off a boat.  I figure it will charge several batteries per charge and the genny could charge it in between.

So, at the moment i can do two flights then charge.

My plan is to fly the Yak all summer while saving for the new plane in the fall.

I only wish there were more Imac's this summer!

Brian

by the way Mark, where do you get the pulse batteries?

I am running Gens Ace in a number of planes and they are great. you can get them at Hobbypartz.com. Not expensive either.

I haven't tried the Gen Ace batteries yet, i have been using the Sky Lipo's for a couple of years now and they are very good batteries...not sure how they compare.

BTW, the nice thing about Hobby Partz is the $10 flat fee shipping!!

Brian