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 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 
    | 
  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".  |  
    | 
  New heavy duty, front 
  electronics tray with encapsulated foam lined battery box!! No More Batteries 
  coming loose in pirouettes!!!!!!  |  
    | 
  New Integrated easily 
  accessible switch mount capable of handling all switch sizes.  |  
    | 
  Main Frame is capable of 
  handling standard collective pitch controls or Hirobo's SWM (swash mode) 120 
  deg. CCPM system.  |  
    | 
  A 10mm hollow main shaft is 
  included to handle the stresses of rotor head loads on the main frame. Super 
  strong, super light |  
    | 
  New larger Bearing are used 
  to support the collective lever system for complete "slop" free smooth control 
  for any flight envelope.  |  
 
Drive Train 
    | 
  New triple bearing supported 
  clutch/clutch bell system to handle .30 to .50 class engines.  |  
    | 
  New Fan/Flywheel assembly 
  (starter pulley) for improved centring on engine crankshaft. 
  
      | 
    Fan is factory drilled to 
    accept magnet for a throttle governor.  |  
   
   |  
    | 
  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.  |  
    | 
  Accepts a DTDS (Direct Tail 
  Drive System) option conversion set for tail drive authority under all 
  conditions! Great for aerobatic autos.  |  
    | 
  A belt driven tail utilizing 
  a lower friction belt is standard equipment. an optional Torque tube pipe 
  drive will be available separately as well.  |  
    | 
  New larger pulleys allow 
  stronger belt contact under the severest of conditions.  |  
    | 
  All rotating shafts are dual 
  ball bearing supported for smoothness.  |  
 
FZ-III Rotor Head 
System
 
    | 
  6mm solid axle with internal 
  threads for securing the blade grips.  |  
    | 
  Floating axle design with 
  wide dampeners for extra support of the Feathering spindle.  |  
    | 
  Thrust bearings are standard 
  for smooth collective changes through the entire pitch range especially under 
  the demanding loads of radical 3D flight.  |  
    | 
  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  |  
    | 
  Head button for "palming" 
  the rotor head is standard.  |  
    | 
  The FZ-III Seesaw features 
  adjustable Bell/Hiller ratios for all flight styles similar to ratios 
  successfully used on the Freya.  |  
    | 
  New stabilizer control arm 
  strengthened for those unexpected "oops"  |  
    | 
  Over 22 degrees usable 
  collective pitch available  |  
    | 
  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 
    | 
  For .30 Size Sceadu, 550mm 
  new design factory assembled wood blades are included as standard equipment.
   |  
    | 
  For .50 Size Sceadu, 570 FRP 
  (fibreglass) main blades are included as standard equipment.  |  
 
Tail Rotor System 
    | 
  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.  |  
    | 
  Each Tail Blade Holder uses 
  a single thrust bearing and radial bearing for exact rotational movement.
   |  
    | 
  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.  |  
    | 
  Tail Boom Mounted Servo for 
  tail control is standard equipment - Also available a 5mm control rod to 
  replace the 2 mm existing rod.  |  
 
Muffler 
    | 
  New higher capacity sealed 
  muffler also included.  |  
 
New Cabin design 
and materials 
    | 
  New shaped cabin is sleek 
  and fast like the Shuttle's Big Brother's, the Eagles.  |  
    | 
  Made of durable impact 
  resistant polypropylene. Blow moulded for smooth round Lines and definitely 
  shock resistant.  |  
 
Tail fins 
    | 
  New larger shaped fins 
  effective in fast forward flight when decals are applied or ideal for 3D 
  flying with their decals removed.  |  
 
Fuel tank 
    | 
  New rear mount location with 
  4 point suspension in the main frame.  |  
    | 
  New centralized stopper 
  allows dependable clunk line freedom.  |  
    | 
  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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