Re: Electric for large Planes

Ok, Ted (or anyone else for that matter), I've looked around the web and 
can't find an explanation for the 4S, 7S,2S terms used to describe 
batteries. I've checked Red's Battery Clinic and other such sites with no 
luck. As is obvious, I'm just starting to get interested in electrics. So 
what does this mean?

Is there a really good place on the web to try to cram all this
information 
into my brain? For that matter is there anyplace that would make some
sense 
out of electric motor sizes for electric airplanes? It can't be all that 
much of a dark science,can it?

Harlan


"Ted Campanelli" <tcamp@[EMAIL PROTECTED]
> wrote in message 
news:XCtlk.7151$cn7.536@[EMAIL PROTECTED]
> Ted shuffled out of his cave and grunted these great (and sometimes not
so 
> great) words of knowledge:
>> Contact Vision Hobbies in Phoenix. They fly a big stearman on the Storm

>> 6374 motor with great success.  They may even have some videos of it on

>> their website at www.visionhobbies.com
>>
>>
>> "Glenn Jacobs" <jakeinhartsel@[EMAIL PROTECTED]
> wrote in message 
>> news:xP6dnaM9No7nDanVnZ2dnUVZ_umdnZ2d@[EMAIL PROTECTED]
>>>I plan to start a 1/4 scale Stearman (Boeing Kadet) this Fall or
Winter. 
>>>I
>>> intend to model the plane flown by Johnny Vasey in the 1949 National
>>> Acrobatic Champion****ps. I will use the Barron plans for the basic 
>>> plane.
>>>
>>> My question is the practicality of using electric power for this 
>>> airplane. To
>>> make it even more complicated as I live at 9,750 feet (2972 meters) 
>>> which
>>> requires significantly more power.
>>>
>>> Is there a conversion formula for Electric Versus Gas? How about 
>>> relative
>>> expense? Certainly not having to clean up the plane after flights is a

>>> plus,
>>> but a negative is the time to recharge batteries.
>>>
>>> Any thoughts?
>>>
>>> JakeInHartsel
>>
>>
>
> I would investigate the A123 batteries.  They are heavier than lipos,
but 
> they can be "quick" charged (if I remember correctly) in about 15
minutes.
>
> It is practical and feasable to do the plane as an electric.  The only 
> "problem" I can see is the battery expense.  I suggest checking out the 
> lipos (and also the motors and ESC) at Hobby City
>
> http://www.hobbycity.com/hobbycity/store/uh_index.asp
>
> Their prices are NOTICEABLY less than stateside.  In 3 years I have had
no 
> problems with their 4s lipos and their motors and ESC (Turnigy and HXT) 
> are at least equal to what is available here.  I do not push my lipos
and 
> I charge them at 1C.  For the difference in battery cost you can get 2 
> battery sets for the price of 1 battery set here.