Vintage RC Helicopters - Hirobo Sceadu
HIROBO Sceadu
Hirobo Sceadu
Named after the mythological Celtic/Norse Goddess who
carried a Bow and Arrows on her back and wore shining armour; twin sister to
Freya.
Known as the Shuttle Sceadu, it was originally intended to replace the shuttle
and thus was available in both '30' and '50' sizes. However demand for the
shuttle was such that the two ended up running concurrently though the Sceadu
was mostly bought in the '50' size.
Sceadu 30-50 build manual
- 2001 version.
Sceadu 30-50 build manual addendum
- 2001 version.
Sceadu upgrades
Hirobo Sceadu Evolution
EVO 50 early
version
After a couple of years the inevitable design update was carried out to
incorporate a number of upgrades. Because it was not a complete new model it was
therefore called the 'Sceadu Evolution' and was available in two forms.
HPM being the originally mechanical pitch version with a rocking cradle and SWM;
this was the upcoming ccpm control system that required a transmitter with
electronic swashplate servo mixing to give both cyclic and pitch functions.
Again available in both '30' and '50' sizes though as before, predominantly
bought as the '50' variant.
SO, WHAT WAS NEW?
The frames were moulded of a tougher material adding strength and
making them more rigid. A third main-shaft bearing fitted below the main
gear further stiffened the frames and give better support to the main shaft for
more precise gear mesh during hard aerobatics. The redesigned fuel tank
held more fuel, and was secured between the frames by four rubber feet thus
isolating it from vibration. Demanding aerobatics makes an engine work harder
and generate more heat so to keep the engine happy the cooling fan was
improved to the increase the airflow over the engine's head. Note that
engine cooling was considered a weak spot on the initial version of the Sceadu.
Main Frame
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All new Main frame design
with integrated, easy to access bearing blocks, integrated cooling shroud, .30
to.50 size engine mounting locations, easy glow plug access, provisions for
routing tail servo wires from the back to the heli to the servo tray, and even
a handy carburettor fuel "pinch off". |
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New heavy duty, front
electronics tray with encapsulated foam lined battery box!! No More Batteries
coming loose in pirouettes!!!!!! |
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New Integrated easily
accessible switch mount capable of handling all switch sizes. |
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Main Frame is capable of
handling standard collective pitch controls or Hirobo's SWM (swash mode) 120
deg. CCPM system. |
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A 10mm hollow main shaft is
included to handle the stresses of rotor head loads on the main frame. Super
strong, super light |
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New larger Bearing are used
to support the collective lever system for complete "slop" free smooth control
for any flight envelope. |
Drive Train
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New triple bearing supported
clutch/clutch bell system to handle .30 to .50 class engines. |
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New Fan/Flywheel assembly
(starter pulley) for improved centring on engine crankshaft.
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Fan is factory drilled to
accept magnet for a throttle governor. |
|
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New drive train layout puts
engine in front of main shaft for better overall CG balancing and allowing the
gear reduction for the tail gearbox to happen at the main gear instead of a
pulley arrangement. |
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Accepts a DTDS (Direct Tail
Drive System) option conversion set for tail drive authority under all
conditions! Great for aerobatic autos. |
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A belt driven tail utilizing
a lower friction belt is standard equipment. an optional Torque tube pipe
drive will be available separately as well. |
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New larger pulleys allow
stronger belt contact under the severest of conditions. |
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All rotating shafts are dual
ball bearing supported for smoothness. |
FZ-III Rotor Head
System
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6mm solid axle with internal
threads for securing the blade grips. |
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Floating axle design with
wide dampeners for extra support of the Feathering spindle. |
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Thrust bearings are standard
for smooth collective changes through the entire pitch range especially under
the demanding loads of radical 3D flight. |
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New heavier duty blade grips
with a 4mm blade bolt are standard for the ultimate in reliability. Accepts
12mm root Main blades with 4mm bolt hole |
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Head button for "palming"
the rotor head is standard. |
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The FZ-III Seesaw features
adjustable Bell/Hiller ratios for all flight styles similar to ratios
successfully used on the Freya. |
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New stabilizer control arm
strengthened for those unexpected "oops" |
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Over 22 degrees usable
collective pitch available |
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Stabilizer Blades feature
adjustable weights and are secured to the flybar with dual set screws. Same
paddles included on the GPH346 and Shuttle RG |
Main Blades
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For .30 Size Sceadu, 550mm
new design factory assembled wood blades are included as standard equipment.
|
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For .50 Size Sceadu, 570 FRP
(fibreglass) main blades are included as standard equipment. |
Tail Rotor System
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Uses the successful Freya
Double pin type tail pitch slider for precise tail control. Slider is dual
ball bearing supported with "a" links to a ball joint on the tail blade
holder. |
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Each Tail Blade Holder uses
a single thrust bearing and radial bearing for exact rotational movement.
|
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New aggressive super stiff
tail blades are included as standard equipment for the 9 3/4 inch tail rotor
disk. Super tail power for today's demanding gyros. |
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Tail Boom Mounted Servo for
tail control is standard equipment - Also available a 5mm control rod to
replace the 2 mm existing rod. |
Muffler
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New higher capacity sealed
muffler also included. |
New Cabin design
and materials
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New shaped cabin is sleek
and fast like the Shuttle's Big Brother's, the Eagles. |
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Made of durable impact
resistant polypropylene. Blow moulded for smooth round Lines and definitely
shock resistant. |
Tail fins
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New larger shaped fins
effective in fast forward flight when decals are applied or ideal for 3D
flying with their decals removed. |
Fuel tank
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New rear mount location with
4 point suspension in the main frame. |
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New centralized stopper
allows dependable clunk line freedom. |
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Now 370 cc, increased 120 cc
from the previous Shuttle Tank of 250 cc.
Very
transparent for easy fuel level checks. |
Sceadu review - Review of early
version by unknown reviewer
EVO 50 later
version
A few minor changes were later made to the EVO; the rotor head
was changed to the FZ-IV, featuring a machined aluminium centre block and had
the flexibility to be configured to meet pilot's proficiency level. For example,
the head featured an "auto-stability" configuration that made it a stable
trainer however, moving a few control balls and changing their pick-up points
made the helicopter a potent aerobatic performer. Some other highlights of
the Evolution were push-pull linkages, two-piece flybar paddles with adjustable
weights and a longer-than-normal tail boom so 600mm-long main blades could be
used.
Sceadu review - Review of later
version (with OS Hyper 50 engine) by unknown reviewer
Sceadu Evo parts - Optional parts colour chart
for the Evo.
Hirobo Sceadu Evolution Final versions
The helicopter was further developed finally into a 90 size
version. No info currently held on these later versions.
Hirobo Sceadu Evolution Documentation
Sceadu Evolution HPM build manual - 2001 version.
Sceadu Evolution SWM build manual - 2001 version - note that parts listings are missing.
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