#720 HIDF Twin Otter Recon

DHC-6 Twin Otter from Revell (04901 in 1:72), as seen commandeered by HIDF Gendarmerie and pressed into service as a reconnaissance and special ops platform. For the Micro Machines Podcast HIDF GB.

Here’s a quick demo..

Notes

I’ve had the Revell DHC-6 Twin Otter No. 04901 in 1:72 sitting in my stash for a while. It’s an “OK” kit and I love the float configuration, but I was searching for diorama inspiration.

When I head about the Micro Machines Podcast Horizon Islands Defense Force Group Build I thought .. ahah!

Paint Scheme

Main colors used for the plane:

Ground-work was a mixture of Vallejo Model Color and Mr Hobby Aqueous.

HIDF - Horizon Islands Defence Force

HIDF comes from the Arma3 game. Since I’ve never played it, I am totally faking it when it comes to the lore;-)

All I know comes from the Horizon Islands - Armed Assault Wiki, and the Micro Machines Podcast - Episode 22 (Horizon Islands Defense Forces)

Circuit Design and Electronics

Motor Control

I’m using two DC 3V-3.7V Coreless Motor 0408 for the props in the plane. They are nice and small - 4mm x 8mm - with an unusually long 7mm shaft making it easy for direct drive installation.

These motors spin anti-clockwise when powered +ve to red lead. The model props are pitched to spin clockwise - so wire motors in reverse (+ve to black lead).

Mini-gun Simulation

Aside from an impressive visual display, the mini-gun hide the in-flight mounting. It is simply a 255mm Yellow LED Soft Silament / silicon rope DC3V controlled by a 555 timer astable configured to run at 10.213 Hz

Fire/Explosion

The fire/explosion effect on the base is animated with a couple of 5050 LEDs:

• controlled with an OpAmp-generated triangle wave to give a slow “glow” effect
• driven via an amplified current mirror for better LED brightness control

Final Protoboard Build

After checking all the electronics, I fitted all the circuits onto a 4x6cm protoboard with micro USB adapter for power. Here’s my plan of the layout with the final build:

Connectors from plane:

Build Log

Customising the interior with open doors ready to take some heavy metal payload..

Some micro motors are going in the props.

Motors installed and basic interior completed

Main parts primed

Starting to build up the “original” scheme (that will later be over-painted with khaki)

Preparing the crew and miscellaneous interior fittings

oh shit, tick-tock, better get moving. carry on, unblock, gotta get my build in.

Just sprayed on some HIDF markings on my “field-applied khaki” over the original yellow of this Twin Otter that’s been commandeered for island recon and covert ops. Classified weapons system is still under wraps;-)

Hope to get this completed by the weekend - all the bits are coming together (slowly!)

First Flight

First flight of the HIDF Twin Otter specops gunship. Based on the Revell 1:72 kit, this has been adapted for the @micromachinespodcast HIDF group build

Final Gallery

HIDF Twin Otter Recon/SpecOps

There’s a backstory here ofc, but I just heard it thru the grapevine. Something like: an ex-Canadian Armed Forces DHC-6 Twin Otter was on charter in the Horizon Islands when the South Pacific Disaster struck. Needing only moderate repairs to get her back in the air, the DHC-6 was commandeered by the Gendarmerie and pressed into service for island reconnaissance and covert operations. The interior was stripped and left with open side hatches to provide maximum payload flexibility - from transporting medical supplies, to extracting a tactical response unit. Although intended for stealthy operations under the radar, port and starboard waist gunner positions can be fitted with a range of equipment, up to and including a wicked mini-gun for when things get a little hot.

About the build: this is the DHC-6 Twin Otter from Revell (04901 in 1:72), modified to take motors for each prop. The mini-gun fire hides the in-flight mounting - 1.5mm annealed florist’s wire from Knorr Prandell. The explosion/flame effect on the base is animated with 5050 LEDs.

The electronics to control the motors, mini-gun effect and explosion are all mounted on a small protoboard. Motors - 555 timer-based PWM circuit for independent variable speed control. Explosion - variable current glow effect driven by OpAmp triangle-wave oscillator. Mini-gun - LED rope driven by 555 timer.

Credits and References

• this project on scalemates
• DHC-6 Twin Otter Revell No. 04901 1:72
• Horizon Islands - Armed Assault Wiki
• Horizon Islands Defense Force - reddit
• 1PC DC 3V-3.7V Coreless Motor 0408,412,612,615,617.716,720,816,8520,1020 High Speed RC Drone Strong Magnetic DIY Aircraft
• 255mm Yellow LED Soft Silament / silicon rope DC3V
• LM555 Datasheet