Aussie Fruit Bat

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Instructions. - Don't bother building  this. The Super is a much better aircraft! But... The Dimension "150mm" on the right hand side should be 250mm !

You will need a computer radio with elevon mixing (or a third party elevon mixer) to fly this. Cut the wing and its doubler approximately to dimensions shown. As long as they are symmetrical about the center line the dimensions don't have to be exact. Cut out bottom flute  6 flutes from trailing edge. Cut a slot on the centre line to separate the elevons - about 3mm clearance. Glue wing & doubler together with contact cement. I have had great success with 'Selleys Gel Grip' contact cement. It sticks really well and is not as messy as the liquid. Smear a good coat on - the gel is ready to joint within 10 minutes. 

Use commercial control horns or the "remnants" of your last crash. Set them about 100mm from the centre line of the aircraft.

Cut out one fuz / tail combination only. Then cut two fuz doublers. There is no need to double up the tail section. Glue these together with contact.

You now need to figure out how to join the fuz to the wing. I cut slots in the wing on the centre line and cut matching 'tenons' in the base of the fuz. About 3 should be ok. Cut one at the front to help stabilize the firewall. 2 more about 100mm long worked fine for me. The tenons should be 8 mm deep so when assembled they are flush with the bottom of the wing. On the firewall I cut a slot 12mm wide (= 3 sheets of Coro) on the centre line. Chop a matching tenon on the front of the fuz and assemble.

Get a good quality hot glue gun (not one of those $3 specials from the discount store - I use a Bosch), check everything is roughly square run a good bead along the joints. If you have cut the tenons tightly then you will never get it apart again.

- Again - the engine mount/firewall used in the super is a much better deal. Its cheaper too!

You need to construct a firewall to hang an engine on the front using a commercial engine mount. I used 2 pieces of 30x30mm thin wall aluminium angle about 70mm long. About 50mm along the alloy cut one side only of the angle. Put it into a vice and bend the angle beside the cut 90 degrees. You should now have an 'L' shaped bit of aluminium angle. Make another one ensuring you create a left & right hand pair. Fit these to the front of your bat. I relieve the joint where the fuz meets the wing and insert the firewall pieces so the small leg of the 'L' is actually underneath the wing. This provides a 'crash guard' at the front of the machine. Attach using 2 decent size nut & bolt sets to the fuz and one either side through the front of the wing. Make a couple of large washers from the alloy and use these on the top of the wing. Drill and mount the commercial engine mount on the alloy firewall
 

My latest AFB uses a Thunder Tiger PRO 36 and usually spins a 10x5 prop. Its a good combination. I have used an OS 32SX running a 9x6 Master Airscrew Scimitar profile.  A good 25 should push this along fine.  

Attach the servos with double sided tape and some wire ties. Don't worry about drilling holes - pushing a small phillips head screwdriver through the coro works just as well. Wire Tie a 6oz fuel tank near the firewall. My receiver was simply attached with double-sided tape and some small ties. The aerial is run out through 2 small holes in the tail.

Centre of Gravity is about 290 mm from the trailing edge. Move the bits around to get this. Better nose heavy than tail! Set the prop so it clocks horizontal when the nitro ceases flowing! You will need some bright wing decoration. This gadget gets out of sight real quick. Best part is on the turns the wing gets a beautiful curve. Looks a bit like the space shuttle is a way!

Set the elevons with plenty of travel. When the fire goes out in front this baby glides marginally better than a brick so plenty of "up' helps. Launch by hanging on the the fuz and launching underarm at least when you launch it is heading up! Some low rates of 60% and about 25% negative exponential are recommended as well.

If the field is empty you can swing this gadget around in 5 metre circles at one third throttle all day. I also love low passes at 1 metre. 

If you need more info

tglynn.at.hotmail.com   (you know what to do with the .at.)!

Here is a picture of an original AFB.

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