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The PERFECT two seater local plane for the modern age.

No question of thread drift here, because there is actually a two-seater version of the Harrier. It’s probably the perfect one too, having it in your back yard.

Private field, Mallorca, Spain
That’s only half of the story. A Lycosaur has good efficiency at one single point of rpm and load, and it requires careful fiddling by the pilot at that point to achieve OK efficiency. The 912 iS is optimized for all loads and rpms and achieves good efficiency every time without the pilot having to do a single thing. In practice they are not comparable. The 912 iS is far ahead.

Where did you get this info?

If true, what if you are using a constant speed prop?
Also, Lycoming is building fadec equipped engines too now, they use them on the Tecnam P2012 and we will probably see more IE2 engine models in the future.

You are also using the term “Lycosaur”, it’s easy to write off their engines by saying they’re old. But they have a proven record, you know what you’ve got, they are reliable and do what they are supposed to. There’s a reason why they’ve been around for so long. Even then, Lycoming is trying to implement more modern technologies into their engine designs (both new engine designs (like the IE2) and to upgrade current engines (Lycoming electronic ignition systems are EASA certified since last year). I do have to say variable ignition timing (spark advance) is only available for a limited number of engine models, they said it was due to most engines not being approved for variable ignition timing (yet) while using unleaded avgas (which they are working on together with fuel producing companies, it has to be a drop in replacement fuel for their entire line of engines). We’ll have to wait to find out.


Eagle20 wrote:

If true, what if you are using a constant speed prop?

That is with a constant speed prop. The Rotax iS wasn’t always like that. Don’t know exactly what Rotax did on the first iS engines, or why, but they were by no mean optimized. They fixed that later. Even so, they are not “optimal” like modern car engines for instance. A Lycosaur has to be tuned manually, and it’s only the mixture that is tunes, since ignition is fixed. Just take a look at all of what is written about “LOP”, and you will see that the average pilot is not exactly an expert.

Also, the 914, as all other Bing carbureted Rotax engines, offer no means to manually adjust the mixture. They are even worse than a Lycosaur, but still manages to get decent efficiency.

Eagle20 wrote:
There’s a reason why they’ve been around for so long

Lots of reasons, and most of them has nothing to do with being a good engine. Electronic ignition has been around for ages already for the experimental market. It offers some minuscule improvement in efficiency, but mostly it’s about reliability. Those mags are probably the least reliable part of the engine.

Eagle20 wrote:

and we will probably see more IE2 engine models in the future.

Hardly. With the speed of production and the price of that engine, combined with the super niche market it’s meant for, most of us will not even see an IE2 engine from afar What we will see are lots of Rotax iS engines in different variations as well as third party development “clones”. We are more likely to see more of those small TP engines than IE2 IMO.

It’s just the way things are, and have become. For anything commercial, you want to fill the tanks with Jet A1. Everything else are peculiarities, super niche stuff. If it’s not commercial, it’s recreational. Recreational aviation lives by a different set of rules. We measure “success” in hours flown per year (around 100 is OK, less than 50 is too little, more than 150 is excessive ) Obviously the best way to achieve that with limited means of time and money is by scaling down in size and opting for high reliability. We want cost per hour to be small, and we want the aircraft to work every time we have time to fly. A two seat with a Rotax is the best we can do today. This is however offset by lots of factors. The fun factor, the cool factor, the “look at me” factor and so on Which is why a 130 HP turboprop or an M14P makes perfect sense, and so does a Continental from the 30s.

Last Edited by LeSving at 22 Feb 07:23
The elephant is the circulation

Last weekend I did some short flights in 3 aircraft, all with different engines.
Super Guépard Rotax 912
DA 40D Continental 135
1946 Nord Renault 6Q-10.
The Nord was the quickest and by far the most fuel consumption at 50l per hour
Then came the Diesel fuelled DA40 at 19l per hour and approx 5knots per hour slower than the Nord.
Finally came the SG at around 10 litres per hour (doing circuits) but in cruise would be between 13L and 15L per hour at speeds of between 90knots ph and 100knots ph.
All engines ran smoothly.
Comparing engines is really a personal thing. I like the Rotax because it costs a lot less than the others to overhaul or replace. And to compare apples with apples, except for the Nord all have a TBO in certified aircraft of 2000hours. As do most Lycoming and Continental pistons in this power range.
100LL is expensive in France compared to the UL95 we use in the SG. Diesel is more expensive than the UL95 but does not cost as much as 100LL. UL95 is also the cheapest of the mogases.(if that’s a word
Oil for the Lyconti engines is much more expensive than the oil (motor bike oil) used in the Rotax and oil changes need to be more frequent when using Avgas.
As I said all engines ran well and I don’t have a problem flying behind any of them. So engine choice is a matter of personal preference based on mission and where in the world you live.
I have become quite a fan of the Rotax 912 having recently converted to it and probably if I had to make a choice between Lycoming, Continental (even those which use mogas) or Rotax912, I would probably go Rotax. There are advantages to the Continental diesel in this part of France, but they are becoming expensive. We (the aeroclub) are due to replace ours this year and are soon to hold a meeting about whether or not we should sell it and go Rotax. Our DA40 currently flies around 400hrs a year. The SG does approx the same but whereas the DA40 is reducing year by year the SG hours are increasing.
“You pays yer money and you takes yer choice”


What about an XCub?

O-360 runs on Mogas, pretty fast despite STOL capabilities and EASA certified.

I know the Ultralight scene is dominant in Italy and the less regulated regime vs. certified planes provides some benefits. However, entry restrictions in some adjacent countries are a limiting factor: MTOW in France limited to 525 kg, separate entry permit required for Switzerland, etc…

EDNG, EDST, Germany

IMO X-Cub is positioned, at around 300-400k USD, as a “third fun plane” for owners that already have a Turbine and fast SEP cruiser.

always learning
LO__, Austria

DA40 fits your profile.

Regards thread title : perfection is an impossible goal.

EGLK, United Kingdom

The X-Cub is just silly in Europe when you can have the Carbon Cub UL. The press release doesn’t tell what the empty weight is, but MTOW is 600 kg. 160 turbo HP from the Rotax 916 iS. With one person and some usable amount of fuel, it weighs in at about 500 kg I would guess. The X-Cub will be at least 650 kg in the same configuration.

Looking at the numbers:

  1. X-Cub, 180 HP : 180/650 = 0.28 HP/kg
  2. X-Cub, 215 HP : 215/650 = 0.33 HP/kg
  3. CC UL, 160 HP : 160/500 = 0.32 HP/kg

The UL will have fairly identical power loading as the 215 hp X-Cub (assuming one person on board and some fuel). But, the UL is much lighter and will fly circles around the X-Cub when it comes to STOL performance. What you cannot to with the UL, is to load it down with 2 persons + luggage and stuff “needed” for exploring Alaska Perhaps not the most useful attribute in an aircraft placed in Europe IMO.

This is of course the whole point of the CC UL. None of the Carbon Cubs are selling anything worth mentioning outside the US. So they made the CC UL. A light weight Cub with the newest and meanest from Rotax, the 916 iS. The aircraft is purpose made for the European UL market. But it will also be the best STOL performance aircraft they have ever made by far, so it will be very popular also in the US. It will not be cheap though, that’s for sure

The elephant is the circulation

The CC-UL isn’t available yet, it’s still in development phase, so there’s no point. (They just made a prototype for Red Bull), Maybe in a few years. They do offer some other models too, but I guess the X-cub is the most advanced product they’re currently selling (if you don’t go experimental and build your own thing from a kit).


Eagle20 wrote:

The CC-UL isn’t available yet, it’s still in development phase, so there’s no point

Point of what? You can order one today if you want. You won’t get it until sometime in 2025 though However, you have to wait this long and longer for many aircraft that have been in production for many years already. Try to order a Shark. You will be lucky if get it this century

The point was that these Carbon Cubs are not very popular in Europe. There’s no use for such an aircraft, and the market is dead. There are a few Norway/Sweden though (two of them close by me). You have to have a very strong Cub fetish to fancy one. But they are cool indeed, and it’s not like I don’t understand why people fancy them. The CC-UL is very different. It heads straight into a big market as a purpose built STOL with some real performance. There’s no need to have a Cub fetish to fancy one, but it’s still a full sized Cub.

The elephant is the circulation
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