Kyosho Spitfire

Kyosho Spitfire 40

Mk V A W3185 "D B"

I've been looking around to find out whether or not the markings on the model are authentic – they are! The serial number is "W3185" with markings "D B" which indicates it's a Mk Va flown by Douglas Bader in 1941, called "Lord Lloyd I".

The Spitfire has been in construction since Winter 2000. One reason for that is that I've been waiting for a suitable retractable gear to become available. The intended gear retracts inwards from the wingtips which is not what the original did. Here I found a suitable retractable that moves only about 80° so the track is wider when lowered.

The engine I chose is a Jeti Phasor 30/3 brushless with 10x 2400mAh cells. Sounds not like much and I won't be sure it's enough until the first flight.

Sep 18 2003 First flight! A beautiful day although maybe a bit gusty and windy. We don't have a paved strip and the grass isn't exactly level which worried me. Rudder check, nose into the wind and full-throttle. After about 8m the Spitfire was airborne although a bit unsteady. That was mainly caused by some gusts and me being a bit shaky; it got better rapidly.

The plane handles really nice and the silhouette against the sky is just awesome. Some people from my club told me that it would never fly with only 10 cells and that I'd need at least 100 W/kg thrust but the power of the Phasor really suprised me. I was flying half-throttle most of the time and while the top speed was not hotliner-style it was more than appropriate for the size and type of the model. I was even able to glide sometimes.

As expected the landing was a bit troublesome with the wheels only marginally ahead of the CoG so it was a nose landing but nothing was damaged.

For safety reasons I didn't use the retractable on these first flights. This probably was a good thing since the push-rods turned out to be too weak and caused the right gear to collapse during the second landing.

Oct 09 2004 It turned out during the summer that the engine setup with only 10 cells is a bit risky, especially during take off. It's OK in a moderate breeze but without head wind it can go wrong. And of course it did. Twice actually but the first time I was able to get the plane safely airborne after some pretty intense moments. The second time however I didn't and the plane touch the ground with the left wingtip and turned a half cartwheel. The wingtip broke off and there was also some damage to the rest of the wing. Nothing too serious however and I hope it will fly again soon. I will however go up to 12 cells and maybe another engine as well. (I'm currently thinking of an AXI 2826/12 outrunner with a 11x8 prop.)

Jul 31 2005 Still flying the Phasor but with two extra cells and the reduced weight really helped. Take-offs are much less shaky and the top speed is impressive. I can fly half-throttle most of the time and it still looks very war-bird like. We did some measurements today: 40A @ 11800 RPM. That's about 480W and I'm very pleased with the current setup. One thing I'll try is a 10x6 prop.

Apr 21 2006 The flight time with the 2200mAh cells was only about 3 min. and more than once I barely made it back intact. Some measurements showed that the pack only yields about 1700mAh so I replaced it with 2x6 cells 3800mAh (pushed+matched) which should help somewhat with the flight time. Con: the pack is about 1/3 heavier. I need to update the weight measurement.

The two cell packs are connected via a Y-wire and charged together. This apparently is a bad idea since the charger turns off way too early. I now charge them separately and am getting good results.

Jul 10 2006 :'-( Bad day yesterday. First my transmitter battery died (luckily before take-off), then I crashed my Spitfire during take-off. The same old problem: started with full elevator up to keep the nose out of the grass which led to premature take-off with too little airspeed. Usually I level the elevator while the wheels are still on the ground once the speed is high enough. Anyway, plane took off, banked left, banked right, rolled left on the back and crashed. Shit. Left wing-tip and the tip of the aileron broke off, also some minor damage on the body. I haven't decided yet if I'm going to fix it or not... I'd hate to have a kind of patch-work finish so this would have to be remade entirely.

Wingspan: 1440mm
Weight:   3072g (body:2155g, wing:917g)
Motor:    Jeti Phasor 30/3
Cells:    12x 3800mAh NiMH
Prop:     10x6
Kyosho
Spitfire electric conversion

Kyosho Spitfire 50

Mk LF VB X4272 "SD J"

Mk LF VB X4272/SD-J of Flt Lt David Fairbanks, No 501 Sqn, Friston, June 1944

Since September 2008 Kyosho offers a new version of the Spitfire. This one comes pre-installed with retracts, split flaps and is available in an electrified version. They also did a way better job on the finish than on the current one - not the one I had, the version after that. The dimensions are identical to my old Spitfire 40 so I can reuse all the servos etc - only this time with a beefier engine. This is just too good to pass up.

Aug 31 2011 First flight - beautiful! The split-flap has some peculiar properties that make me unsure if it'll ever be of any use to me - at full deflection the plane is raising the nose enough to almost stall, wouldn't want that to happen on final.

Sep 21 2011 Had a few more flights and am getting more comfortable, especially with the landings. What a fscking awesome sight in the sky with gear retracted! She likes to come in fast, full nose trim to keep the speed up, then level out for a smooth touchdown. The propeller setup is very benign; according to Drive-Calc I'm getting (with a simulated 12x6 2-blade prop) ~3.5kg thrust at ~38A and 86% efficiency. I'll probably try a slightly larger 3-blade with more pitch.

Drive-Calculator

Wingspan: 1440mm
Weight:   2760g (body:1820g, wing:940g)
Motor:    TURNIGY AerodriveXp SK 42-60
ESC:      TURNIGY Plush 80A w/ UBEC
Cells:    2x 3S 3000mAh LiPo
Prop:     Graupner 3-blade; 11x7
Kyosho Spitfire 50 EP
Dymond C5055 Auslegung
TR 42-60C 500Kv Brushless Outrunner
Last modified: Sep 2 2011
Copyright ©2003 Ulrich Hertlein