Electric Wot 4
This all came about courtesy of Chris (I've got electrons
in my veins) Traynor when he said I ought to try something electric, at
this point I told him to keep out of my private life and mind his own
business. After a brief foray into the world of 7cell snorers, which was
none too successful, it was decided being as I have methanol and nitro
in my bloodstream that something with a lot more poke was needed to convert
me to electric power. This is when Chris mentioned he just happened to
have an Astro Cobalt 40 lying around doing nothing, after some considerable
negotiation (this is Chris you know) I became the proud owner of said
electric thingy.
Bit of a problem arose, no airframe to screw to the back of the Astro
enter Brian (has balsa dust and PVA for breakfast) Halliwell who very
kindly offered to build a Wot 4 for me (didn't know what he was letting
himself in for) anyway about 5 days later Brian presented me with a brand
new aircraft (I'm not joking this guy builds at warp speed) that was duly
fitted out with all the gear.
Well the time had come, there we all were one cold winters Sunday complete
with a 14 cell and 21 cell power packs and all the other electric paraphernalia.
14 cells were installed for the test flight and it was just me and this
Watt4 sitting on the strip in total silence, I have to say I found this
a most eerie experience, no throttle to blip, no noise, it was just standing
there daring me to hit the right stick so I did and off she went with
authority down the strip and into the air for about five minutes, including
a couple of touch and go's, rolls and loops (they don't call me T&G
Mart for nothing) all in all quite successful.
The wheel fell off so to speak (it was the undercarriage actually) when
21 cells were tried, with the whole plot weighing in at 7.5lbs this was
one heavy Watt4 but the main problem was I'd gone over the speed controllers
max limit and not suppressed the motor.
In the first crash a glitch on finals put me in a small tree and the plane
sustained moderate damage to wing and fuse, three days later (thanks Bry)
this one was far better, it cart wheeled on take off, now when 3lbs of
batteries want to keep going in the direction they were going they usually
do irrespective of where the rest of the plane is going and they did taking
out the fuse on the way, five days later and she's fixed complete with
new fuse (thanks Bry) and I had to think long and hard about this electric
business.
Anyway after fitting loads of suppressors, a dirty great 100 amp ESC,
losing 1/2lb in weight and many hours of technical support with Chris
Traynor, the Watt4 has had about 15 flights without mishap (Brian doesn't
even quietly head for home when I'm about to fly it) and it goes well
for it's 5minutes, still think it would be better with an 80 4stroke though
(sorry Chris just thinking aloud). Well that's about it really, many thanks
to all who helped.
Tech spec Watt4 Classic 52ins
Motor Astro Cobalt 40 direct drive
ESC Astro 204 100 amp no bec (300 nimh flight pack)
Cells 21 Sanyo 2000rc
Prop 11x6 graupner
Auw 7lbs
Amps 40 aprox
Watts 851 input
Martin Arnold
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