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De Havilland DH-84 Dragon-2, RC electric scale 94.7" wingspan, 1/6 scale
On this page you can download the design & construction article and the plans for this unique radio control flying model,
the DH-84 Dragon. I fly it at the club field in Laurel Maryland (FreeState Aeromodelers). The outer wing panels (28"
each) come off without any fuss by removing 4 connection pins per panel. There is no hard attachment for the aileron controls
(done with a push-push system of pin-in-socket), and the wing wires are permanent and do not need adjustment or re-attachment.
This makes for a very easy set-up and take-down, only a few minutes total. The wing wires are functional and very much part
of the structure, just like the real aircraft. Indeed, much of the model structure is very similar to the actual aircraft
in both configuration and function.
See a Youtube video of the Dragon flying
This is another flight on Youtube (better quality)
APL here stands for "Aircrafts Party Limited", an Australian designation
A 12" GI-Joe makes a perfect 1/6 scale pilot, especially if you need a little nose weight!
Specifications
Wingspan = 94.66 inches, airfoil = 10.3% flat-bottomed with slight re-flexed trailing edge
Length = 68.6 inches
Wing area = 1700 square inches
Weight = 14.5 lbs take-off weight, 12.5 lbs without motor or batteries
Wing loading = 19.6 oz/ square foot
Static thrust ~ 10 lbs; Static thrust / weight ratio ~ 0.7
Power System
Motors = Two AXI 2826-10 brushless out-runners, 35-40 amps current each
Props = APC 11x5.5 props
Batteries = Two Poly-Quest TW 4350XP-45 Li-Po batteries (14.8 volt 4350 milli-amp-hour)
Controllers: = Two Jeti Advance 77 Opto plus controllers. These were oversized to guarantee that there will never be a
single-engine situation at takeoff due to one controller slightly going over the current limit.
CLICK HERE TO DOWNLOAD THE DH-84 CONSTRUCTION PDF DOCUMENT
CLICK here to download 2nd construction document with many detaied photos
The drawings for the DH-84 rc model are in a .dwg vector format. Programs such as Autocad or Intellicad can be used to open
it. The drawings are not complete in every detail, and this project is best tackled by an expert scratch builder. Also, the
prototype model has no shock absorption, and from the experience of flying this model, it would do to incorporate Robart shock
struts into the main landing gear. This aircraft loves wheel landings and hates 3-point landings. One must fly it right down
to the ground.
Click here to down load a zip file of the DH84 Dragon plans in dwg Autocad14 format
Click here for a free dwg format viewer
click here to download a pdf file of page 1 of the DH84 plans
click here to download a pdf file of page 2 of the DH84 plans
click here to download a pdf file of page 3 of the DH84 plans
click here to download a pdf file of page 4 of the DH84 plans
click here to download a pdf file of page 5 of the DH84 plans
click here to download a pdf file of page 6 of the DH84 plans
These plans have also been uploaded to the free plan site http://plans.aerofred.com/. Just search for DH-84b
Kinko's and other print shops can print these plans. They will use their "large format" printer. Each drawing
is approximately 72" x 34". You can also email the pdf files directly to Kinko's, or you can write them to a CD
and physically give it to them.
Next is a project in the works, a de Havilland DH-90 Dragonfly, 1/5 scale with a 103" wingspan and twin 0.70 4-cyc
engines
I do not believe this plane has ever been modeled in RC, the real one is a challenge to land (the tail would be shadowed by
the fuselage during a 3-point landing and ground loop), and there were tip stall problems. It is however a very beautiful
looking aircraft, but demands respect.
This is an ACTUAL aircraft, not the model!! Hopefully when the model is completed, it will be hard to distinguish model from
real.
click here to download DH90 plans as they now stand (a little incomplete)
Another set of plans in the works is from a home built aircraft of the 1960's, a modified Stolp Starlet parasol.
The next project is an aerial photographic platform for small point-and-shoot cameras. I want it to be hand launchable
and have an unobstructed view that can be tilted from straight down to full forward(thus twin motors). I call it the Eagle-Eye1,
with 120" wingspan and 1100 sq inch of area.
This is my Wilga 80, 55" wingspan which is electric. You can download my plans
click here to download the Wilga plans in Autocad dwg format
Another set of plans in the works, this is a Bucker 181 Bestmann, scaled to 104" wingspan (1/4 scale). This is another
aircraft that I believe has rarely been modeled in RC.
Next project is one I recently finished, a 1936 Monocoupe 110 Special, "Spirit of Dynamite", 1/4 scale. It
stands at 69" of stubby wing span, 10 lbs flying weight,and ~ 915 sq inches of wing area (25 oz/ft^2). Scratch built
from Jack Swift plans, slightly modified (of course). I use an OS 91 4-cycle which makes it more scale power (no unlimited
vertical, it is scale after all).
This is a fantastic flying model!! Very scale-like in flight, handling and landing. It is a gem of a design!!
This is the way I accomplished aileron differential without separate servos or biased bell cranks in the wings. I put the
bias in the servo arm itself, with servo pushrod connectors on both sides of the servo arm as shown, going to flex-wire pushrods.
The spacers allow motion without running into the center arm connection. There is about 2x as much up aileron as there is
down.
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