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Old 06-12-2004 | 08:54 PM
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watt_the!'s Avatar
watt_the!
 
Joined: Jun 2003
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From: AdelaideSouth Australia, AUSTRALIA
Default RE: F-18 with EDF???

Hi Carl,

A single thrust tube eh?

Cool. The reason that i'm skeptical is that i've heard similar things over and over and over again. I dont doubt that this thing runs very well on the 3s2p setup..awesome in fact...

but what i here almost continuously are claims like " it wont fly etc." on less than such and such setup.

it applies to glow and electric setups. For instnace , the huckebein thread that almost insisted on a vasa fan and a fairly expensive setup...for it to fly well. although any numbers ran through the kontronic site's tests for the vasa fan versus the stock alfa fan didnt seem to justify the $300 price tag difference between a "cheap brushless setup" and the "vasa one"...not to mention the time taken to do all the mods.

i see that if 3s2p is used with the fun 400-36, thrust for the f18 will be around 840g.- 29 oz.

this, with your AUW of 29oz, without batteries..starts to make sense. If your battery pack weighs 8 oz assuming 120g per pack of 3s lipos, then your thrust to weight would be:

29:37 or 0.78:1

which is pretty good..adn should give great performance. However, the cost of that setup would be around $75+$150+$150 = $375US. Which isnt too bad i guess.

I am seeing at kontronic, that if i single 10C 3s pack was used, with the fun 400-28, for 20A or so, 610g thrust is attainable. The AUW would be around 26oz + batteries, or around 30oz.

This gives a thrust to weight ratio of 21:30, or 0.70, for a cost of about $50 + $75 +$120 = $245US. Considering that my huck hauls a** at less than 300g thrust and 590 g AUW, and takes off from grass, then i'm thinking that 0.5:1 thrust to weight is quite acceptable. Hence my incessant questions about this model. Actually, i'm thinking that since T:W is still 0.7, i can "afford" to go even cheaper!!...lol..

any comments?..

I still need some convincing here as you can see!... but please dont take this the wrong way, I'm trying to sort through the jungle...

Cheers!

Tim.