1/4 scale Mk.1a Spitfire

[Phil Clark]

This Spitfire project has been on the go since late June 08. Another project for Ali's stable, though this one is to be a 'Team Scale' entry for Top Gun 2009. Full composite construction, but with traditional structure on all control surfaces etc.....

Power is a little unusual as it's coming in the form of a Hacker H-200 electric motor, running 10 or 12s LiPo's, 13,200Mah. We aim to run a scale diameter 32" 'Solo' variable pitch 3 blade prop and will also have an onboard sound system using a Merlin soundcard from Thomas Benedini in Germany (3 x 5" speakers and 3 x 2x40W amps). AUW is expected to be in the 45/50lb range.

Detail will be....uhhh, as much as we can fit in......'inside and out'.............

Photos etc coming soon...............

Phil

[Dave Parry]

Can't wait to see it hope your pic's will be posted soon

[Jason Griffiths]

Same here looking forward to pictures off this,i love Spitfire's

[Nigel Wyatt 2653]

Likewise. Can't wait to see the pics and hopefully the model at a show next year. Just one thing Phil are you wishing the years away or did I miss one? (late 2009??)
Happy Christmas to all

Nigel

[Phil Clark]

Some of the detail on the rear fuselage.......



Fabric covered rudder with rib stitching & tape detail plus trim tab actuator and nav light fairing.



Main fuselage former that the pilots seat will be mounted off......

[Phil Clark]

Currently working on the flaps which have the scale tubular spar and the actuation horn that pops up through the small door on the top wing skin.........



....and finally for now, the big washing machine motor that going in the nose!!!

[Nigel Wyatt 2653]

Looking fantastic Phil. Thats some power plant. Where does the power station go!!!

Nigel

[Jason Griffiths]

Yep agree looking very nice

[Dave Parry]

Phil, another show stopper in the making I see

[Phil Clark]

Fun & games detailing the flaps over the last few days........

[Phil Clark]

All done....on with motor & ESC install + associated colling ducts now.

Phil

[Jason Griffiths]

Coming on nicely Phil

[Phil Clark]

Flaps & ailerons now pretty much complete. The original model was supplied with composite simulated fabric covered ailerons.......but AR213 (The Mk.1a based at Booker) which we are modelling has metal covered ailerons, so new surfaces were built and finished traditionally.........

[Phil Clark]

BIG electrics are all a bit new to me, so after seaking advice on cooling requirenets....we've come up with the following..........

The small carb air nttake under the nose feeds a smoothly curved and diverging duct, passing forward through the firewall into a chamber behind the spinner. A duct with around 3mm clearance around the Hacker H-200 with a bellmouth intake is fed by this incoming air....'hopefully' most of the air passed through the motor via the front and rear holes rather than going around it. At the rear of the motor, the duct diverges again allowing the heated air to pass through the 4 slots in the firewall, into a plenum chamber (not get fitted) on the back of the wirewall. As the cowling exhaust openings are present and the resin exhaust stacks will be hollow, most of the air should be sucked from the cowl via these openings........as the full length of the duct is diverging, the air pressure will be constantly dropping so we hope it sould draw it's own air through and out pretty well. (Time will tell!!)

[Phil Clark]

Complete cooling duct with 'lost foam' moulded front section.............

[Phil Clark]

Hacker H-200 with the full bellmouth motor duct.....and with the top half removed to allow motor removal (front former not yet fitted.

[Phil Clark]

Finished lower bellmouth duct and front inlet duct ready to bonded into the fuselage moulding...............

[Jason Griffiths]

Coming on nice.

Looking forward the overall finish

[Phil Clark]

Plenty happening on the Spitfire over the last few weeks........all remaining servos have been installed and the motor and colling duct install is complete. The steerable tailwheel is also complete, but most of the last 2 weeks have been spent concentrating on more of the internal detailing.....

The LiPo's have also arrived (2 x 6s 13,500Mah + 1 x 2s 13,500Mah Dualsky packs to give a possible 14s in total is required), which has allowed us to 'fire up' the Hacker H-200 motor this last weekend. Mated to a 32" 'Solo' 3 blade variable pitch prop, the performance was staggering with in excess of 200A being pulled. Further testing is required to get the right prop for the motor/ESC/cell combo we have (the 32" Solo set at 10 3/4" pitch is too much), but it's looking promising so far. We've also been doing a little testing on the 'Benedini' onboard sound system....we've only had 1 of the planned 3 speakers working at present, but with all 3 linked up, it looks like we should be able to produce around 105dB at 1m..................

Phil

[Jason Griffiths]

Looking good looking good

How much will this Spit be retailing for