Craig
My battery is indeed in the rear. The possibility of adding weight to the
tail was considered, but the amount required was such that the net weight
saving by changing the battery would not be all that significant. It is a
relatively light aircraft as Europas go with a 912 UL engine but with an
Airmaster AP332 VP propeller and the nose near the forward CG limit. I
also understand that adding significant weight to the tail can increase the
propensity to ground loop.
Philip.
G-BWWB Europa Monowheel Classic
*
*
On 28 April 2012 12:49, David Joyce <davidjoyce@doctors.org.uk> wrote:
> davidjoyce@doctors.org.uk>
>
>
> Craig & Graham, Right from the start I planned to have my battery in the
> engine compartment, and it has worked very well. It sits on top of the
> passenger footwell with a one inch retaining wall around its bottom end and
> fixed with a nylon strap from the firewall over the top and down. that is a
> much simpler and lighter mounting than any I have seen in the rear. I have
> an Oddyssey 17 amp hr battery which has had more than enough welly to start
> the engine instantly even after a 3/12 break in the winter. I made no
> provision for cooling and it doesn't seem to have noticed.
> As to weight and balance I have a mono XS, 914 and a Woodcomp SR
> 3000 W wobbly prop and a very well equipped panel (although much of this
> electronic rather than steam age!), so my plane might be expected to be
> nose heavy. I calculated what I thought was the optimum position for the
> Ready for Service C of G as what would allow any combination of pilot/s,
> fuel & luggage and came up with the figure of 59 ins or thereabouts (but
> the precise figure will depend on the base weight of the plane but I guess
> the optimum will be very close to this) To achieve that precise CoG
> position I found I needed a small, 3 lb block of lead bolted to the front
> of the tail bulkhead (accessed conveniently through the trim slots). I
> suspect I had saved most or all of 3lbs in longer cables and more elaborate
> mounting & fixing of a rear battery. My advice would be to assume this is
> wha.t you will do with the battery and only shift it to the much more
> inconvenient rear position if your plane turns out to be unexpectedly tail
> heavy.
> Regards, David Joyce, G-XSDJ
>
>
> GRAHAM SINGLETON
> <grahamsingleton@btinternet.**com<grahamsingleton@btinternet.com>>
> wrote:
>
>> Craig,
>> you're right. moving the battery forward would require roughly half it's
>> weight in the tail to compensate.
>> You save the weight of the cables too. You need to consider keeping the
>> battery cool if it's in the engine bay though.
>> Graham
>>
>>
>> ______________________________**__
>> From: craig <craigb@onthenet.com.au>
>> To: europa-list@matronics.com Sent: Saturday, 28 April 2012, 0:04
>> Subject: RE: Europa-List: starter battery - LiFePO4
>>
>>
>>
>> Philip
>>
>> You mentioned the issues of weight and balance, for not using
>> the LiFePo battery, assuming you had the battery in the rear
>> As per most builds, was the option of another half kilo of ballast
>> near the tail considered, if so and you opted not to proceed
>> Could you explain why. Given the weight saving would still be
>> about 6kg, it would seem worthwhile to pursue
>>
>> Craig
>>
>
>
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