Hirobo Paraplane Sport

Review and Enhamcements

Original Specifications Overall body length:406mm Overall body height:458mm Flight condition:1,120mm Flight speed:22-26km/h Flight time:3 min. Battery:8.4V 1,700-2,400mAh Ni-cd battery Motor:Mabuchi RS 540VH high power motor Propeller:14x7 Gear ratio:3.8:1 WingSpan: 59 Inches, Width: 25 inches Wingarea : 1475 Sq inches Allup Weight: 44 Ounces,1234 grams Information: http://model.hirobo.co.jp/english/   Direct link to paraglider Fullscale: http://www.paraplane.com

This review contains information on how to get your stock paraplane sport in the air with the least of hassles
and also notes on what you need to do to ensure a trouble free day at the airfield.. This article will also
cover some enhancements and tests and a final conclusion on how to make the model a really fun machine with
adequate duration.

The paraplane sport's steering system is based on a TILT BAR.. So far
all the commercial models on the market has a FIXED canopy support bar and
steering is done by pulling strings (Brake lines) on the back the of canopy..
The advantage of the brake line system is that you can carry lots more
weight and you can also flare during landing without power.

The tilt bar method works best for rectangular canopies and not
very well for those thin long kites like the Thunderfoil Kites or
Go-fly-a-kite parafoils.

With a tilt bar system, almost the whole weight of the model needs to
be serviced by the single servo everytime it pulls the model. This
means that your servo needs to be a strong one and if you ADD
any more weight to the model you add additional stress to the steering servo.

The tilt bar system requires only 1 servo to operate and it is located
on the CG of the model. Tilting the bar to one side, shifts the balance
and the model turns. (see the full scale link for a techical explanation)
(http://www.paraplane.com)

Lets get started
============

When you order the model make sure you also order

1 Spare carbon tilt bar

Quick System Summary - Package for initial testing as used by author

• 7x Sanyo 2000 SCR
• Robbe 40 AMP speed control with BEC
• lightly Greased Gearbox (remove the gearbox , apply lithium grease and re-assemble)
• Balanced prop
• METAL GEAR SERVO
  
• Velcroed backend for battery (added by author)
• Human Helper for ROG
• Stock Hirobo paraplane unit..

Model Assembly requirements

• Remove the prop and balance it by applying a light coat of thick CA where the
  prop is lighter. Use CA Kicker and a tissue to wipe off excess , sand , rebalance until
  prop is fully balanced.
  
• Arrange the canopy hooks vertically on the tilt bar and tighten the screws

Pre flight mental activity - Thinking in your head.

• The canopy is not properly trimmed (always the case)
• Get ready to keep the aileron stick to one side of model
  if it keeps turning to the other direction
• Get ready to flip the trim to the opposite side

Tools to bring to the flying field

• Pliers
• Philips screw driver
• Spare parts - Tilt Hang Bar

Face the Wind before launch

Pre-flight activity - ROG

• Re- Charge the 7 cells before flight to give 9.5-10 volts (A MUST FOR ROG)
• Make sure aileron stick is 100% no dual rate
• Set your timer for 3 mins
• Get ready mentally to trim the model
• Position the model into the wind (3 mph - 6 mph)
• Helper lifts up the canopy 90 degrees above tilt bar
• turn on timer
• Apply 50% power Slowly
• Model will track into the wind
• Apply 100% power
• Model will take off
• Model may waddle like a DUCK, leave it as it is , when you turn away from the headwind, the waddling will
  stop.. This is caused by air not being able to escape the canopy and the model is moving too fast ahead..

• Quickly trim the model for straight flight and save it for the next flight

Full power into the wind	good airspeed

Flying

• When the model has gained enough height, turn away toward the downwind side
  to cause the model to speed up and climb..Do a climbing circle, fly in the direction that would
  cause the model to keep climbing.
• Keeping the model into the wind may make it stay stationary.. If it is flying into the wind and climbing, leave it as it is..
• 
  
• Listen out for the timer to 3 mins alarm
• 7 x 2000 cells with ROG will last you about 3.5 - 4 mins
• The model should have climbed to about 200 feet or more by now
• Trim the model

Landing - little wind - at 3 mins alarm

• You need a little power to flare before landing
• Chop power to 0%, , circle slowly and let it drop to a few feet above your head's height
• Power on slowly
• cut power when flaring is complete

Landing - with wind at 3 mins alarm

• You will need to prepare to land from 3 mins onwards
• Note that turning into the wind will keep you from the landing
  site, so that you will need to keep power on- don't do this
• Cut power to 0 %
• Turn downwind
• The wind will blow the model in downwind
• you will rapidly lose height
• At about twice your body height, power on and turn into the wind
• Model will slow and float
• Land with power on

Flying tips and Warning

• In order to HANDLAUNCH the model , you need wind of 5 mph or more... This allows the
  canopy to inflate WELL before you attempt to launch the model. Face the headwind, walk briskly
  so that the model is almost trying to fly off from your hand, LAUNCH the model and apply power
  immediately. In my case, I use my mouth over the throttle stick here.
• Do not try handlaunching in poor wind conditions where the model does not have a tendency
  to take off... in that case you would need to do a run on the ground..
  
• Always fly as high as possible and then throttle down to enjoy the glide or slow movement
  forward with some power on
• Do not power on so that the model is stationary in the wind unless you are performing some flying stunts
  This is wasting battery and could stall the model

• If you wish the prop to be moving, at least power on so that the model is gaining height or moving..
• Make sure you rest the model 10 mins or more between flights to cool the motor/gearbox.

A very nice addition to the flying field

Original gearbox with Clutch

When using the original gearbox

• Do not use more than 7 cells
• Lightly grease the gearbox with Lithium Grease or Tamiya titanium grease

Speed Control

• Use a 40 AMP speed control with BEC to keep things cool
• Full current draw is 32 amps with a warmly charged battery

Servos

• Always use METAL GEAR SERVOS , plastic gears will break on a hard landing.

Enhancements and Modifications to the Model

I have decided to modify the model for enhanced performance and here are the results..
Reasons:

1) Hirobo gearbox will lose its teeth at 8 cells because of heat buildup.
2) The 540 can motor has good performance but as you can see from the results, I am truly enjoying
myself with a LRP car motor.

Ferrite Version
==========

1) LRP Generation X 16x2 double wind car motor, timing at 2 degrees, on Hirobo Prop
2) Master Airscrew gearbox , 3.5:1
3) Powered Flight time: 6 mins on Sanyo 7x 2400
4) 40 amp Robbe Speed control with BEC

Any car motor that is around 16 - 15 turn would do. The original motor has a RPM/V constant of 3425..
A rebuildable car motor can be timed to your liking and this is like changing a 16 turn into a 15 or a
17 turn by changing the timing.. I timed the motor 2 degress in the direction of the desired rotation to
give about 1.5 to 2 amps at 0 load.

I chose the LRP Generation X - 16 x 2 double wind because they are cheap and out of fashion
for (US$30.00) old price - US$90... .. people are going for Trinity D4 car motors.. we don't
need that..

Current measurements

Current Draw: 7x2000 @ 9.5 volts fully warmed ,charged
watts: 313 watts, 33 amps.
prop: Hirobo 14x7 plastic prop. (balanced with CA)

ROG Take off requirements: 80 Watts per pound minimum

Kontronik motor with aluminum mount
and fiberglass cloth with Wood brace.

Brushless Version
============
1) Kontronik B/L 480-42 and 4.7:1 gearbox on Hirobo Prop
2) Axon Gearbox (Pre installed)
3) Powered flight time: 3.5 mins on sanyo 7x2400
4) 40 amp Kontronik with NO BEC
5) 4x 600mah NIHM Cells.

Climb rate:

With the Kontronik Brushless, the climb rate is very impressive, lets give it a number - 10 for fantastic performance
The climb rate of the LRP motor I would say is VERY VERY good - say 7 compared to the brushness motor..

The major shock to me is that the Kontronik lasted only 3.5 mins. I was informed that this is due to the POOR
performance of the software in the speed control that caused the system to be inefficient at throttle setting below 60%..

The LRP brushed version lasted 5.5 to 6 mins with power left for flaring..

Since the paraplane is meant for a lot of cruising, the throttle would be about 40-60% most of the time.. this
manifested the problems in the Kontronik controllers today.. Schultz has a new series of controllers that is
suppose to address this problem.. See http://www.schulze-elektronik.com/fut-e.htm for an explanation.

Master Airscrew 3.5:1 gearbox. Note template and Note that the tilt bar
philips screw is reversed with the lock nut now in front.

Click to download full size template
IE (right mouse,save as)

You must use a dremel tool to SAND AWAY the clutch formations on the prop. Then you sand the surface FLAT.
You also need to use a Tower Hobbies prop Reamer as the prop hole is a metric 5mm, using a tower hobbies reamer,
I widened the hole to the regular US size hole , which will then fit the master airscrew prop adaptor. You would find it
useful to MARK the front of the propeller with a marker pen on the prop hub area.. The reason is that the prop is WHITE
and you have a tendency of making a mistake. The Prop must mount with the front part of the hub mating with the master
airscrew prop adaptor..The back of the prop has slotted holes .. See the Kontronik Mount picture above... Mounting the prop backwards will still fly the model but with about 20% reduction in power. From behind the model, the prop should rotate CLOCKWISE.

A template is required for attaching the MAS gearbox. Print it on a printer, Spray 3m77 on it and attach it to
some very thin aluminium. Cut and drill out the holes.. You may need to lengthen the Metric M3 screws ..

Next, Adjust the pinion gearbox for the MAS gearbox until all the pinion contacts the main gearbox on a
1 to 1 meshing.. You Can do this by pushing out main gear and prop shaft from the mas unit and
then while holding the motor on your hand

1) Place the template onto the face of the motor
2) Place the BACKPLATE of the Mas gearbox onto the template
3) Place the main gear of the MAS gearbox onto the backplate
4) Here you can then see if the pinion gear's meshing is a complete 1:1 mesh, if not, adjust the pinion gear.
5)Once you have done this, apply a drop of locktite onto the pinion gear and later grease the gears.

Reassemble the gearbox and it is now ready for installation

1) Remove the tilt bar screw
2) Place the LOCK NUT which was at the back , to the front position and insert the long Philips
3) Screw from the BACK.
4) Put in the template and the MAS GEARBOX.

Note Lock Nut is on the front now	Fishing Clevis replaces the original hooks.

The original canopy hooks on the tilt bar were replaced by strong fishing clevises.. The original hooks
has a problem of bending very easily.

The fishing clevis is oriented vertical and tightened. A loose clevis will cause the model to swing to
one side during takeoff. Check to make sure the clevis does not swing freely, if it does , it is because
the plastic inserts in the carbon rod is loose. USE CA to fasten it properly.

Attach a self adhesive Velcro on both sides of the battery compartment.. So that when the battery is inserted, a non-adhesive Velcro strip can be placed across the hole to prevent the battery from coming out. You also need to TEAR OUT one side of the internally attached soft Velcro for the flight battery to go in faster... (Non-adhesive velars are sold at DIY clothing outlets)	For the Antenna, use a hard left over sullivan pushrod or if using the original antenna tube, apply GOOP adhesive to glue the tube to the prop ring, otherwise the original tube likes to get sucked into the prop . A longer sullivan pushrods keeps the antenna away from the prop.

Windows Media MOVIES

Take off (with head wind)	Landing (with strong wind) (KEEP CHILDREN AWAY- See video)

Click on the links to see the takeoff and landings, Windows Media Player is required... Get it here

So here is the final configuration for the enhanced Hirobo paraplane

• Metal Gear Servo
• LRP Generation X 16x2 double wind motor
• Master Airscrew 3:5:1 gearbox
• Original 14x7 Prop sanded flat and re-drilled
• Sanyo 7x2400 cells
• Robbe 40 Amp RSC 840 with BEC
• Fishing Clevis replaces original hooks
• Velcro protection for battery

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