pylon500

I've had a little to do with this J230 version over the years, still only flies like a Jabiru (take that whichever way you like), but fairly good utility. Bit of a beast with a Lyco 233 up front, and the U/C on this one is possibly just a little far forward, which keeps you on your toes..

Looks like the quick or the dead! I missed this post, and have a mate that wants to sell his RV4, is looking for something with better short field ability, not necessarily STOL, just a slower/shorter strip requirement. Sure you don't want two?!!

Um, yes, well I've been away for quite a while... I've wandered over into a different realm, and dabbling as an amateaur writer! Was just having a bit of a break and came back here to see what's happening. I'm probably not very good, as a writer, so will probably come back eventually. The differential system is typically being used on all these small contra-rotating helicopters.

OK, makes a little more sense with the chordline diagram. I'm assuming it is the tip section that has the twist, as opposed to the whole wing? Having the taper ratio change at the tip (getting proportionally wider) is going to do some odd things to the span loading on the spar out there, but probably OK. There does seem to be some pointless complexity going into this thing, to say nothing of the overkill of rivets from what I can see so far. The spar rivet pitch looks OK, but have look at the rivet pitch on the wing ribs of a Cessna or Piper, not unusual to have nearly 2" pitch on only 3/32 rivets. Still not sure what the scalloped doubler on the ailerons is for? I had promised myself not to get too involved as I figured most beginners pick up some of the standard way of doing things before they get too far in, but your resources seem to be able to let you go ahead in leaps and bounds... Maybe missing a few pointers along the way? Can't find the 'chin scratch' emoji

If you could keep this in 95:10, you can have as many props/engines as you like. As for contra-rotating, just a quick scribble... As I say, only a quick scribble, probably a lot of little details to sort out, but you get the idea...

If this wing flies, you will be surprised how even a small amount of non-moving tip trailing edge will dampen aileron response. That is if that end bit of trailing edge is not going to move. My second aircraft had a wingtip similar to the Sapphire, with (admittedly) a small aileron. Roll response was not startling. Later, the trailing edge was cut off and joined to the aileron, giving much better roll control. I was initially going to go with just a left wing, but was convinced to add a right one as well...

Some companies spend years researching wingtip design; Some don't think it matters...

Will have to give kudo's to Jab for that gear leg! Landed in a plowed paddock and splintered, but still supporting the aircraft!

The 'plastic' blades referred to are the original 'Ultra-Prop' propellers. The plastic blades were a bit of a compromise between production and performance. Enter 'Aerofibre', a composite blade maker in Queensland, who produced the 'Brolga' blades to suit the Ultra-Prop hub system. Upon his retirement, the Brolga blades were produced by Bolly. Interesting looking blade, and if I read right, they will be moulded plastic like the original Ultra blades... Hopefully the MARAP process should sort this out.

Yeah, there is that problem. I suspected as much. The original plastic blades, although they look primitive, actually work fairly well and can easily be cut to length. You avatar talks of a WB582, I would have thought you should be using a four blade prop for that power and diameter? No, I don't have the time to make/repair props, sorry. A friend had the three blade Bolly on his Fisher 503 Drifter, very nice, and quiet. Had a minor hub issue, but Bolly sorted it, a good prop.

It will be interesting to see what the blades are like. Are you actually getting 'Brolga' blades to suit your 'Ultra-Prop' hub, or the plastic 'Ultra-Prop' blades? As I mentioned, when the Broga manufacturer retired and sold the business to Bolly, they said they updated the blades, and with it the price. Not saying they are a bad blade, in fact they ARE better, but at $1,200 for three blades, I decided to make my own. I don't even have an Ultra-Prop hub anymore, just the blocks.

New tanks, new canopy, bit of a buff, no problems...

Saw the prototype of this (probably that one) at Oshkosh '13. Slick as an RV, simple as a Sonex, designed around a Corvair engine, but would take a Jab3300. Folding wings. Was very tempted... It is currently a single seater, but I think a two seat could be in the works, but would compete with old RV4's.

So I went back and had another look at the pictures, and the video footage (which didn't run the first time?). In the close ups on the video footage, I'm fairly sure now that the line across the animal track is definitely the impact mark of the entire leading edge. In some views, you can almost make out the impact marks of the wheels and the nose impact point is quite obvious. The fact the wreckage appears to the right of perpendicular to the leading edge impact line would imply some rotation at the time of impact. No tire marks are evident leading to the wreckage. The distance travelled by the wreckage does equate to a low horizontal velocity, however, the amount of destruction is indicative of a reasonably high speed, more likely in the vertical axis. Beyond that, the picture, and it's quality, are insufficient to postulate further, although the brownish triangle shape spreading from the primary impact point is possibly the spray pattern of a rupturing fuel tank (I think the Fishers have fibreglass tanks like Drifters?), which has killed the grass. None of these observations can definitively state the cause of the accident, only surmise the events post impact.

Something must have gone seriously wrong to leave that impact mark.

? Meanwhile, back at the weight and balance test topic.... Logged into the members portal to do the test, and the first thing that happened was the password I got, was in confusing font, where I had to decide if I was looking at a 1, a small L, a capital I, and then a zero, or an Oh?! Managed to log in the third time. Then spent an entire afternoon trolling through all the mixed info from various official sources; 1975 D.O.T. (Australia) weight control regs, 2011 CASA maintenance regs, 1945 FAA AC 43/10 weight section, 2009 Some word doc discussing W+B, CASA exemption 49/15, And assorted video's. And then delved into the test questions and finally the exam. So, anyone that knows me, knows I've got a pretty good handle on most aspects of design, thus weight and balance, I've been weighing and assisting weighing for a few years now. I will be the first to admit that over the years I've got a bit lazy, and now days I use an excel spreadsheet to do all my W+B work. It's a good app, and I understand how moving things around effects things, and know how to adjust things in the app. Naturally I figured if I've got to check some figures, I'd just use the spreadsheet. Two things popped up; ⁕I overlooked that the actual figure questions were purely mathematical, yes, you need to draw columns and crunch numbers, ⁕The diagramatic aircraft as pictured is basically improbable in the real world. (Don't try to work out the CofG as a percentage as real designers would) The latter being the problem that slowed me down as I tried to reverse engineer the plane to get logical results. End result, failed! No feedback, so idea where I went wrong. Gotta re-engage my old brain and try to learn all the 'different' ways of doing what I've been doing for the last thirty odd years....

Actually, I, pylon500 and two mates are embarking on a new project(s), and we're gonna need all the cleco's we can get our hands on. If anyone has spare/leftover/finished with cleco's, PM me, and we'll look at some sort of deal.

Prop doesn't look like it was developing much power at impact.

He was lucky the parachute didn't tangle with the wreckage. While most ultralights have ballistic deploy systems, that will get the chute clear of the aircraft, hang glider just a have a hand deploy, and they have been known to tangle and not deploy fully.

Unfortunately there are those that will try to 'DRIVE' Foxbats (and Vixens) onto the ground, much too fast, and there are a few broken nosewheels around the place. Even flapless, a Foxbat should not touch the ground above 45kts, and the nosewheel probably shouldn't touch till below 30kts. This is such an easy aeroplane to land...

Thruster?! Nah, it's a Javelin. Another project I'm supposed to finish for a mate (he's in no hurry, got two other planes...)

I've just realised that talking about making props is a bit of a thread drift, so I'll leave it there for now, but will post a link to photos of 'One I prepared earlier'; https://get.google.com/albumarchive/113292981019876413104/album/AF1QipO4Yp7-E7wI6rRX5D_BcFVgmQVh_enL5dZJ3e1O

With the timing and everything, it really was one of those $hit happens scenarios. Although he did seem really positive about making sure it wasn't his fault...?

Well according to most Skyfox/Gazelle owner/pilots, the RAAus office for one..... I know no one else likes/wants them..