rotax618

G'day Jimbo I have an SPG2 gearbox 2.5:1 which was sold by Airtrikes Canada for Suzuki, Subaru and BMW engines, unfortunately th bellhousing I have is for the Suzuki G series engines but it would not be difficult to build an adaptor plate to suit. The gearbox was good for 160hp much stronger than rotax C. Want $500 for gearbox and bellhousing.

That is a really good lesson, could you post the URL so I can send it to some of my friends who tend to fly with a little more bravado than they should.

Basic training" If you want to go up pull back the stick, if you want to go down - pull the stick back further......

I have heard of certain persons using out of date Jet A in their diesel vehicles with no problems.

Yep, the homemade Swiss Muffler only lasted 800 hours because a flexible pipe broke. Maybe Swiss Mufflers should be banned. - honestly. Read Tony Bingles' Book Firewall Forward.

If you want an efficient and very quiet muffler that takes the heat out of the cowl, look up "Swiss Muffler" A Swiss muffler would be easy to fit to a Sav and would also lower the chances of CO poisoning.

The position of the nosewheel relative to the rudder has a large effect on roll, particularly if you have tundra or similar tyres. Just because the aircraft rolls straight when the rudder is centered is no indication of alignment. The position of the rudder varies depending on the "P" factor at varying throttle positions. The engine offset is a compromise to keep the "P" factor manageable through all power settings. As the nosewheel touches during a crosswind landing it has to be kicked straight. It doesnt take much adjustment of the nosewheel relative to the rudder to change the roll characteristics. If the roll is only slight then gently bending the trailing edge of the flaperon up or down using you fingers will usually fix it.

The upgrade Im talking about was the early VG savannah to 560kg. It consisted of thicker wing root mainspar fittings and doubling the outer mainspar strut attachment, fitting 2 extra bulkheads to the rear fuselage and doubling the lower rear fuselage angles. I fitted the VG leading edge at the same time as suggested by ICP - the leading edge made very little difference from the old profile , slats off and Stollspeed VGs. ICP supplied new chrome moly outer main strut fittings which were undrilled. Pretty simple to change the dihedral, doesnt need a big increase but +1 - 2 deg gives a vast improvement to lateral stability. Dont modify anything unless you are sure you know what you are doing, having first discussed it with the importer Reg Brost.

The neutral roll stability of my VG annoyed me and when I did the 560kg upgrade I was able to increase the dihedral because of the new longer strut ends. The Sav is now a dream to fly, I can fly hands off even in thermally conditions. Can open out maps, get a drink and something to eat without having to immediately grab the stick because of unwanted roll. Just compare the dihederal of the standard Sav with, skyfox,foxbat, jabiru etc etc.

Check the nosewheel adjustment with reference to the rudder, the nosewheel is in the prop slipstream and can have quite an effect on roll. The fact of the matter is that the VG Savannah doesnt have enough dihederal and any slight out of adjustment will cause an annoying roll.

I wish you well - please start a builders blog to keep us informed on your progress,I have no doubt that the concept is sound. Cheers

I have been following Hugh's work for some time, I would wait until the prototype has been flight tested and the bugs worked out. Flying Plank tailless aircraft are VERY sensitive to the CG, retracting the undercarriage towards the rear may cause complications. In my opinion the design has merit but because of its unconventional layout I would proceed with caution.

The aspect ratio of a circular wing is 1.27, it has been found from experimentation that wings with aspect ratios from about 1.2 - 1.4 behave like wings with aspect ratios of approx 5. Provided that the relationship between CG is kept in the 25% range Circular wings haven been found to be very stable and have some unique low speed characteristics, it is no accident that Davids UFO flies very well, is stable and controllable.

There are a few XL owners who found that out.

The firewall is the same size, only its about 6 deg more upright on the XL ans S.

You have to wait 6 weeks for them to read your file, if they request anything (photo or WB ) you go back on the bottom of the heap and have to wait another 6 weeks - a total of 3 months, thats what has happened to me - how fair is that?

G'day, here at Casino the Council requires the owners of all non commercial aircraft hangared at the field to pay a user (landing) fee of $150/annum. Commercial operators have to pay more, but we don't have any commercial operators at present. Itinerant aircraft are supposed to pay an $8 landing fee via an honesty box, naturally nobody pays although training schools from Coolangatta land here several times every day. The Council also requires all locals prove they have $10mil public liability but they ignore itinerants. Not really fair!

One of the 'S' Savannahs down here has cracks forming at the ends of the angle across the top of the firewall. Have you seen any problem up your way

We got 0.09 - 0.1, certainly smoothed things. Thanks

By the way - thanks for the loan of the prop balancer.

I got the alloy sliding gate tracks and ball bearing wheels from a place near Danny Leach's, but you can buy them from most retail alloy suppliers, the tracks come 6 metre lengths in 2 sizes, I used the larger size extrusion and wheels. I put silastic under the tracks and screwed them down to the concrete floor using countersunk blue coloured concrete screws you can get at Bunnings. The wheels are fitted into a box which has a flange at the base to screw into the bottom of the door frame.

G'day Mark, you will probably regret hanging the doors from the top, every hangar around here has had to convert to bottom tracks. The conversion is easy just instal a couple of alloy sliding gate tracks and wheels. Apart from making the doors easy to open and close particularly when its windy, if you put the tracks down on silastic then they provide a barrier to stop water being blown under the door.

This is a shot of the bolt.

I built a small PA door into one of the centre sliding doors and a simple gate bolt into the floor.

The attached sketch is probably something like what you are thinking.