sfGnome

16 hours ago, RFguy said:

It's not unusual to find a 1000 to 1999 hour rotax you can afford which has plenty of good hours on it and put a big bore kit on, (yes aftermarket)   There are a couple of major players that have variations. Mark Kyle  might chime in.....

 

Thanks Glenn. I’ve dug around a bit and I can see why you are suggesting a big bore kit. However, when I read your conversation with Mark on this subject (https://www.recreationalflying.com/forums/topic/37555-rotax-912-minimum-things-that-need-to-be-done-for-specific-hours-up), I ran screaming from the room. 🫣😝 I have expertise in all sorts of odd subjects, but engines aren’t one of them, so I the absence of knowledge, equipment and/or knowledgeable mates close by, I think that I have to stick to shop bought. I’ve budgeted for a new motor, so that aspect doesn’t worry me.

22 minutes ago, RFguy said:

go with a big bore 912(low compression)  and a afterthought turbocharger.  Or if you are scared of heights and heat , just a 912ULS with big bore kit.

All I know about Rotax engines is what I can see on their website, so what is this big bore 912? an aftermarket mod?? Where do I go to learn about these (what I assume to be) non factory options? Thanks

1 hour ago, skippydiesel said:

Ah yes BUT the type of aircraft should be your mission objectives and the type of engine required to motivate the airframe to meet the objective(s) Not really practical to separate or select engine first & then airframe.

Definitely airframe first, which dictates the engine options. I’m an engineer, and I know enough to know that I DON’T know enough to start fiddling with what the designers settled on. One of my two selections specifies a particular engine, so no choice there. The other specifies the range of Rotax engines, hence my initial question.

Thanks for the comments thus far. Keep ‘em coming! 😀 I will note that I’m only talking about engines - not the aircraft that they’ll go in. I’ve spent the last few years going through all the mission requirements and have narrowed the aircraft choice down to two (and no, I’m not going to drift my own thread by disclosing what those two are 😛).

I’m seeking the wisdom of the elders (and youngers, for that matter), but most of all, I DON’T want to start a religious war!

I’m looking at various aircraft that can be registered in the soon-to-be(!!??) 760kg Class G. Some are designed around Rotax engines, which I’m completely comfortable with. I’ve flown behind the 100hp 912ULS fully loaded to the 600kg limit plenty of times and never felt like it was not powerful enough (although that’s possibly because I’ve never flown anything more powerful). The 915 and 916 are out of my budget, so I’m left with the choice of either the 912is (fuel injected) or 914 (turbo). 

I’m not a back country, huntin’ n fishin’ type bloke, so I’m not looking for STOL performance, and I like to fly high (more efficient, smoother, and I just like the view from up there - I’d go into space if someone gave me the gazillion dollars), so… the question for you all is, “is it better to have a more powerful engine that also works better at higher altitudes, or a lower power one that doesn’t have carbies with all the problems that they entail”? More importantly, why? Any other reasons for the selection that can be thrown into the mix are welcome too. 
 

Lighting blue touchpaper and standing back… 😛

Yep. My son-in-law has put an epoxy down on his shed floor, and it is *so* easy to sweep out. However, it did scratch quite easily when something sharp was dragged over it.  One of these years, the DA for my shed will be approved, so I have to decide. Epoxy so it’s easy to keep clean, heavy duty vinyl or timber to help it keep warm (and a bit easier on the legs when you’re standing for a long period), or just bare concrete. Dunno. Guess it depends on how far the budget stretches. 

A bit off topic (sorry!), but what is the finish on the hangar floor? 

1 hour ago, onetrack said:

I was always under the impression the instant a craft left the ground (or water) and became airborne, held aloft by air flowing over and under wings, it is classed as an "aircraft". This bloke seems to have convinced the bureaucrats otherwise.

I was reading an article the other day about a ground effect vehicle (I’ll hesitate to call it either a plane or a boat) in the US that has umpteen zillion dollars in advance orders from various airlines for transport over water, and it is classified by the government as a boat. 

You piqued my curiosity, so I checked. AC91-17 says that the minimum size is 200mm diagonally (although it notes that “some manufacturers may vary slightly from this minimum, but may still be acceptable”, which I believe was included because one of the iPad minis was something like 198mm). 
 

We chose it because of limited dashboard space, but obviously bigger is better if you can fit it.

16 hours ago, flying dog said:

I *thought* (yes, dangerous) there was a screen size minimum and the mini wasn't up to spec.

I used to use a mini, and it was fine. Don’t know if there was/is a spec change that would change that.   

How strong are the parts you make, Mark? Do they have a weakness along the joints between layers, or do the layers bond really well? I used a lot of prototype parts at my last company, but we always had to be really careful to not stress them. 

Regardless of whether you’re dealing with a compass or a magnetometer (from your reference to ‘electronic gizmo’), the effect of equipment in the aircraft is not linear around the circle, so the errors need to be checked at at least the 4 cardinal points. The assumption then is that the errors will be reasonably linear between those points, though if they are quite disparate then there would be value in checking more points (or, better still, finding the cause of the disparity).

Interesting. Air services has just published special conditions for Bathurst airport during the Mt Panorama races next weekend (https://www.airservicesaustralia.com/aip/current/sup/s23-h65.pdf). VH and foreign aircraft have no restrictions and need no permission, but RA-Aus aircraft are banned. I understand that it will be busy with all the A-listers being flown in in their private jets, but to assume that RPC pilots are intrinsically less capable than their RPL counterparts is a bit rich. 
 

Ok. Fire at will…

5 hours ago, horsefeathers said:

I built my first commercial system using CP/M running dBASE II, on an Osborne dual floppy machine, and later used Kaypro computers, which were not quite as glacial as the Osborne, and had a better screen. Ahh, they were the days.

I used to develop software on an hp machine with one floppy drive. The disks were too small to fit the editor, assembler and the source code, so I had to have two disks, one with the editor and the source, then copy the source over to the other disk which had the assembler to compile it. Slow, fiddly and error prone. Definitely not the good old days… 🫣😁

17 hours ago, red750 said:

The Planet Satellite was a British light aircraft of the late 1940s. Designed to exploit new technology, the aircraft was abandoned after two crashes although the innovative fuselage was later incorporated into a helicopter prototype.

 

That is such a cool looking aircraft! The lack of later craft following that format (that I know of) implies that there is something intrinsically wrong with it, but wouldn’t it get attention if it landed at your local field. 

If you use a thin plastic bottle and screw on the lid at 10,000ft on a cold day, then when you land the combination of much higher pressure and a drop in the fluid temperature means that the bottle is now much smaller than it was… Just hope that the plastic doesn’t do a rapid unscheduled disassembly. 🫣

This is second hand information, but a bloke told me recently about problems he had with lane failures that would disappear when cycled. The problem in that case was a poor joint in one of the sensor cable connectors (don’t know which one). Something to look for if you haven’t already. 

One of the things that we found when we lived in Europe was how many of their places are named after Australian towns… 😛

Before today, if I was to tell you about my last flight, it would have been April, 2016… Yep, as of today, I’ve taken the first step back to fully operational. Just an hour with an instructor getting comfortable in the air again and finishing with a couple of circuits. The last circuit got a bit interesting, with an RPT departing, two other lighties in the circuit, one overflying, and an emergency chopper departing as well. Let’s just say that it was a *very* wide circuit! Thankfully, the instructor said “you just fly the plane; I’ll handle the radio”. 
 

Hopefully, next week I can get the BFR ticked off. 🤞

Regardless of what it is, why does there appear (in the original photo) to be a large chunk missing from the fuselage just forward of the tail feathers? 🤷‍♂️

13 hours ago, Old Koreelah said:

Mine is military-looking green, but I’ve heard of others being bright orange.

If you were James Bond, then yours would be a giant Union Jack… 😛

Stop trying to persuade me. If the plane doesn’t kill me, my beloved will! 😝

20 hours ago, facthunter said:

Wouldn't be much harder to build the real thing. I've always wanted a Bleriot Xl.  Nev

It was a picture of a Bleriot XI that piqued my interest in aviation. I was only about 8 at the time, but I thought “I could build that!”, and the thought has never left me. However, these days I think “where’s the roll-over protection?”, so when I build, it won’t be a Bleriot… 🫣

You’re brave, going shotgun. That’s ugly country down there (well, not ugly. It’s beautiful, but mighty scary in a single engined aircraft). When I used to fly from Cessnock, I’d always go up to Mudgee way before turning south, but maybe I was just taught to be a scaredy cat. I used to work with a GA pilot who couldn’t understand why I didn’t want to fly direct. 

Good thinking, 99! I’ll bet the installation was a whole lot simpler without walls getting in the way (and you never know, you might get around to adding the walls some time in the next decade or so… 🫣)