X-Air Flight Reports

So this is a story about a recreational aircraft and a users perspective on buying, owning, converting to and flying a low inertia / high drag, ugly little cutie called an X-Air. And yes, this 60 knot "rag and tube" ultralight is a long way from the slippery 175-knot plus Mooney and Seneca II twin engine aircraft I used to own, but I just fell in love with the X-Air with its agricultural look and its back to basics flying.

It's all Michael Coates' fault. Michael's the Australian distributor for X-Air and several years ago, $15 got me a demo VHS tape of the three axis ultralight aeroplane called the X-Air. For some reason the tape also contained a promo on another, but vastly different aircraft from the opposite end of the velocity spectrum, the slippery and sophisticated “Sting”.  Sure the Sting was ultra smooth, very technical and fast as hell, but there was just something super appealing to me about that little X-Air. The thought that you could remove the X-Air's doors on a balmy summer afternoon and just poke around at fifty or sixty knots and take-in the scenery was really appealing. The idea that the pilot and passenger sat mere centimetres above the ground behind a low set instrument panel that provided a panoramic and unobstructed view of the runway on late final, meant my non-pilot wife might just be able to learn to fly this aeroplane. And because the X-Air stalls at a miniscule twenty-four knots, meant the landing sequence could be conducted at a more leisurely pace, more time to think, easier to judge the flare height, shorter landings rolls and all those other good things about flying low and slow. All in all, this could be one easy-to-fly, fun aeroplane for both of us.

Back in pre-history when I thought it might be good to get "in the air" again, we investigated microlights (or trikes) with my friend and highly skilled microlight pilot Peter Wilson from Air Escape in Tumut. Trike flying is great fun with the wind in your hair and excellent visibility from the pod, but could Liz my wife, weighing-in at fifty kilos, handle that massive sail in stronger winds? So next stop was to have a chat to the experts at RA-Aus in Canberra to ask the question - are we best to buy a conventional three-axis aeroplane or a microlight? I explained that the winds on Queensland’s Sunshine Coast can be pretty full-on sometimes, and the candid response from Chris, RA-Aus' Technical Manager, was that in general a three axis aircraft is easier to handle than a trike in stronger winds when your upper body strength is not all it could be. OK that's good to know. Chris also agreed that the X-Air was a good little aeroplane with an excellent safety record, as indicated by its general absence from the “Pilot and Technical Notes”  (the accident and incident section) of the RA-Aus magazine.

So while in Canberra, I contacted Tony from Lakes Entrance in Victoria to see if he now wanted to sell his X-Air as when we had spoken six months earlier he had decided to keep it for a while longer. To my surprise Tony said that if I wanted to buy his aeroplane he would be prepared to sell it. So off to Bairnsdale aerodrome, and in the flesh, the X-air looked just a good as I thought it would. Tony who had lovingly build the aeroplane to British BMAA standards, took us both for a flight and the 2200cc Jabiru motor sounded sweet and smooth as the aeroplane settled in the cruise.  So the deal was done and Liz and I returned to Queensland very pleased with our new purchase.

For me the Jabiru motor was a genuine plus on this aeroplane and well worth the extra dollars Tony was asking. Normally the X-Air is equipped with a Rotax two stroke 582, 503 or the older and now discontinued 74 hp 618 engine. The Jabiru engine is manufactured in Bundaberg and is an eighty-horse power, four stroke, certified aircraft engine. Two stroke engines send sometimes-undeserved shivers down the spine of pilots due to their propensity to cease working at the most inopportune moment. However, I understand that late model Rotax 582's are pretty damn reliable and the 50 hp Rotax 503's always had a good reputation for reliability.

The choice of engine is one of the most vexing questions for X-Air builders and the topic always generates quite some activity in the Yahoo X-Air users forum. So for what it's worth, here's my take on the engine selection debate which in this country, generally resolves into a choice of two - the Rotax 582 or the Jabiru 2200. (Although the Hirth, the HKS, the Verner VM133 and the Simonini Victor 2 are also certainly interesting contenders).

The Jabiru engine is, theoretically at least, more reliable than the Rotax 582 (4 stroke vs. 2 stroke), and it burns about 11 litres per hour as opposed to the 582's burn rate of about 15 litres per hour.  The TBO (or time between overhaul) is much longer on the Jabiru engine at two thousand hours (although I would probably start thinking about pulling the head off at about half that) whereas the 582 is recommended at 350 hours. But one high activity user I spoke to had over a thousand hours on a 582 before any major work was necessary. Nevertheless the “book” says 350 hours TBO on the 582 and a new X-Air builder should keep this figure in mind when it comes to thinking about engine choice.

So the Jabiru engine burns about 4 litres per hour less and, on a three-hour trip, that gives the X-Air an extra hour in the air as compared to the 582. So your effective cruise speed on a longer cross-country trip is greater with the Jab engine as you have to spend less time refuelling en-route.

But the Jabiru engine cost a good deal more at almost $14,000 compared to the 582 at less than $9,000. The other issue is that the 80 hp Jabiru engine seems to have more power than the aircraft needs, while the 65 hp Rotax 582 is probably spot-on for the relatively light X-Air. Having said that, the extra power of the Jabiru engine can come in very handy getting the aeroplane off the deck when you're hot, high and heavy or you need to punch your way into a headwind.

In the end the engine choice is a compromise but on balance I think if the budget can stretch to it, my advice would to go with the Jabiru engine especially if you lean toward cross-country work. On the other hand if what you want are just weekend excursions in the local area, it takes a lot of years to reach the 350 hour TBO on the Rotax 582 and the extra 4 litres per hour burn rate is not a significant issue if only flying locally for a couple of hours at a time.

Now I had two more questions, how do I get the X-Air from Southern Victoria to SE Queensland, and who will do my conversion from GA to ultralight? On the latter issue, having contacted most of the flying schools in my area I was to find that they could all train on late model one hundred knot aeroplanes, but no one had the capacity for low inertia / high drag training. Hundred knot aircraft such as Tecnams and Sportstars are very sophisticated, very forgiving, and excellent for training, but their high performance GA type flight characteristics would not give me the different flying skills necessary to help with my X-Air conversion. What I needed was a "high drag" instructor.

The transportation issue was proving equally problematic but Peter Wilson came to my rescue and agreed to abdicate his throne at Air Escape for a few days, deliver the aircraft and do a bit of training before jetting back to Tumut. And what a thrill it was to look up and see our red X-Air overflying its new home for the very first time after its uneventful trip from Victoria.

In the short amount of time Peter had remaining to do some training, I quickly realised that flying a high drag aircraft was... well different... in a harder sort of way. I couldn't even manage a balanced turn properly. I remembered back to my GA training days when you'd initiate a turn and, if necessary, just kick the ball back into the centre with a bit of rudder and viola, there you have it, a balanced turn. But now on the X-Air, that damn balance ball just didn't want to play ball. Under Peter’s guidance I quickly went solo but personally felt that I was a long way from happy with my flying performance generally.

Peter's parting advice was simple - don't give up!  But it's funny how when things are right they are right, right across the board. As "luck" would have it, I ended up sharing a hanger with one Brett Soutter, the CFI of Pro-Sky and one of the only instructors within 60 kilometres I hadn’t spoken to about training. "Sure I can do your conversion" Brett told me. "As well as Tecnams I also instructed on high drag Drifters for 380 hours". Bingo! I had hit the jackpot.

Some GA pilots look down on the ultralight fraternity but what they don't realise is that good ultralight flying in some phases of flight, demands a different, more demanding set of flying skills. In GA training it seems, engine failures are given about as much weight as stalling (twins excepted), but in ultralight training, engine failures are king. If your fan suddenly stops you have got to know how to get your aeroplane into that paddock with as much aplomb as humanly possible. But why all this emphasis on engine failures? Because the unfortunate facts are that ultralight engines do tend to fail with more regularly than the Lycoming and Continental engines fitted to Cessnas, Pipers, Mooneys and other GA aircraft. Having said that, if I am going to have an engine failure, I would rather have it in an ultralight than a GA aircraft any day of the week. The landing roll on the X-Air for example, can be as little as 40 metres.

I also used to believe that it was easier to unlearn something than to learn something from scratch. But now I'm not so sure. For example, the landing procedure with ultralights is very different from the luxury of powered approaches that happen in GA. There's none of this getting the aeroplane nicely lined up with the runway way out on long final, and adjusting out any “glideslope” irregularities by applying a touch of more or less power as you need it.

In ultralight training, every landing involves accurately judging when to turn base (while accounting for wind, potential for sink, proper altitude etc.) pulling the engine at the end of downwind, turning base and doing a glide approach from the base turn and onto finals and then landing the aeroplane all without power. And that happens on every landing so every landing is a simulated engine failure. And, as one recently converted GA to ultralight pilot remarked to me, "Now I feel guilty if I have to resort to a squirt of power to adjust for some error of judgment on finals". But, painful as it is to learn, this training technique really sharpens your spatial skills and provides real confidence that, if the worst happened, you have the best chance of survival.

In one of my moments of exasperated frustration I commented to CFI Brett that the X-Air was supposed to be a forgiving aeroplane. "It is" he said. "It's just that you have to really manage the drag curve because the X-Air washes of speed in the blink of an eye without proper power settings, and it can bite you in the bum real fast if you don't watch your air speed". Brett continued. "What you will learn in your X-Air training will give you invaluable experience for any aeroplanes you fly in the future". (I interpreted that to mean that, if you can fly an X-Air you can fly anything).

But in the end the advice I got to "stick with it" turned out to be good value.  In a few short hours the pieces of the jig saw started to fall into place and now that I can actually fly this little monster with a reasonable degree of proficiency, I love it again.

Is it a good first aeroplane? I think so. It is light to handle, quite roomy with very good aerodynamic stability. Trim the aircraft properly and you can easily fly hands off - great for cross-country trips.  Who needs an autopilot? And for a new pilot, there would be no unlearning to be done in the flying department.  Certainly for me anyway, the X-Air was more difficult to fly initially, I think because it lacked the inertia, the sophisticated airframe and control surfaces - like a synced rudder and flaps, as well as the array of instruments I had been used to using. And after not flying for many years, I was also definitely rusty. At the end of the day, the X-Air is basic "seat of the pants" flying at its best where you are forced to become a good aviator as well as a good pilot.

And for the new recreational owner / pilot it is financially a good place to start as well with a kit built X-Air complete with a Rotax 582 engine getting airborne for about 25 to 40% of the cost of its one hundred knot cousin. If then you find you enjoy your recreational flying and want to go faster with a more sophisticated aircraft, you know that your X-Air flying experience will put you in an excellent position to convert to another aeroplane with a minimum of re-learning.

Along those same lines, the advice I am getting now from people is that I'll soon get board with 60 knots and crave a faster aeroplane for long distance touring. They may be right, but at the moment for me, it's literally the journey that's important, not the destination.

Ross I McRae RAA Member 016484 September 2007

Standard X-Air

The X-Air … an affordable, easy to build and easy to fly Fun-Machine with a lot of bang-for-the buck!

Over the past 5 years I have clocked up several hundred hours ferrying a variety of different X-Air’s around Australia including 160 odd hours in my own aircraft. Powered by the trusty Rotax 582 and 618’s and the 80 hp Jabiru engine they have performed almost faultlessly flying all over the country in the varying conditions that Australia can produce.

My story goes back to about 6 years ago when I was looking for an affordable, safe and easy to fly 2-seater Ultralight; I had to work within a very limited budget so my new aircraft had to be someone’s second hand pride and joy or a new kit running with a second hand engine.

After looking at countless second hand, or as common up to about 8^th – hand machines and a couple of new machines which were financially beyond my budget, I placed a couple of calls to nag Michael Coates of X-Air Australia with all sorts of questions about the aircraft he had just started to import from overseas. Some cash was scrambled between family and friends and we were off on the long drive from Brisbane to Mudgee in NSW, where X-Air Australia was based before re-locating to Queensland’s Gold Coast about 4 years ago.

Having never seen one in the flesh, except for a demo video and a few pretty brochures a fair bit of time was spent with a very patient Michael Coates to crawl all over his demonstrator aircraft, finally he let me have a go at the almost new aircraft around the picturesque Mudgee area.

There was not much opportunity to fully explore the potential handling characteristics of this very neat design, but after a mere 30 minutes of play in the aircraft I was convinced that the X-Air was the right choice, it suited the flying I wanted to do and since there was a kit in stock in the colors we wanted a deal was struck on the spot and the 2 crates were strapped onto the trailer which was brought along – ‘just in case’.

Building the X-Air

First impression when opening up the kit is…. WOW - everything is bubble-wrapped to perfection to avoid any transport damage; we also found the wrapping to be very handy to avoid scratching the tubing when handling the parts during the assembly process. Once the parts are unwrapped I was really surprised to find that there were no messy bags of hardware floating around as common in many kits commercially available, almost every bolt is in the pre-drilled hole it belongs to along with the correct washers, spacers and where applicable nuts just finger tightened.

The assembly process is extremely straight forward; by simply following a detailed and illustrated step-by-step assembly manual, they now also have a 3 hour assembly DVD which is supplied free with each aircraft. Windscreen and fuselage pod assembly is also very simple, with all the parts pre-cut and mostly pre-drilled with exception of the bolt holes to attach the 2-piece wind shield to the pod.

A little bit of planning and detailed work is required during the assembly of the 2-piece composite instrument panel which is also pre-cut and pre-painted (gel-coated). I found that fitting the desired instrumentation and associated wiring loom before fitting the panel and console into the aircraft was much easier than doing it in the plane.

The sporty looking and comfortable (as many hours of long cross country flights have proven) composite seats have their upholstery pre-fitted and are ready to be bolted onto the strong, pre-drilled and pre-cut plywood floor which comes up very neat when covered with marine carpet.

To finish the fuselage and empennage assembly only took about 3 days with the many assistants I had dropping by to check out the new plane, with the fuselage formers being pre-formed and ready to be riveted onto their allocated brackets and all covering being completely pre-sewn and ready for assembly the plane almost grows before your eyes. Tail feathers for example are simply bolted together inside the beautifully finished skins, which ensure a tight fit of the Dacron covering fabric on every aircraft I have seen.

I decided to fit the more powerful Rotax 618 to the X-Air airframe which I had purchased in “due-for-an-overhaul” condition out of the back of a Drifter which was re-converted to a 582 after having done about 350 hours including a long over water flight to Tasmania by a Boonah flight instructor.

The engine was completely overhauled to 0-hour condition, incl. new radiators, hoses, and a new gearbox and with all the work completed it still came in at under half the price of a new 618; it was a real bargain and helped keep the project under budget.

With the engine installed and a new Aerofibre 68inch 3-bladed Brolga prop fitted final assembly was to be done at Barry Hempel’s Hanger at Archerfield Airport with final inspection to be “supervised” by Ian Aviation.

With the relevant paper work completed, the engine run-in, a green light from the RAA and a freshly issued RAA licence which was a quick conversion from a VH-commercial and an overseas Ultralight licence the X-Air was readied for it’s maiden flight.

Following some final engine and control surface (right deflections) checks, the aircraft was cleared for take-off and 1500 ft orbit over the field enjoying the luxury of Archerfield’s main runway.

A string but steady 30 knot wind which was a bit of a concern for me proved to be no problem for this light but amazingly stable machine. Following some basic stall testing, several touch-and-go circuits were completed and before I knew it the first couple of hours in our new pride and joy were already on the clock.

Unfortunately there was no hanger space available for my assembled aircraft at Archerfield and as I didn’t want to leave my new pride and joy outside or take the wings off each day I got RAA approval to fly the X-Air to nearby Caboolture Aerodrome to complete the 25 hours flight test period.

Flying the X-Air

When initially inspecting the X-Air in Mudgee I was somewhat concerned about the relatively flexible mounted empennage, however my concerns quickly disappeared with the next 160 trouble free hours being flown in just over 7 months. Against my initial concerns there was no sign whatsoever of material fatigue. Also, it seems that this configuration plays a strong part in the X-Air’s very soft riding characteristics, especially in rough, turbulent conditions, where the tail and also the flexible outer half of the wing takes most of the shocks in rough conditions.

One of the first things to notice during taxiing even on rougher grass surfaces is the suspension of the landing gear; with its large shock absorbers there is virtually no bumping or rattling noticeable, the aircraft almost glides across the ground.

Opening up the throttle the drum brakes prove to be efficient up to approx. 6000 RPM (with the 3:1 geared 618) and I understand the later models actually have larger brakes again, further increasing the efficiency. Initial acceleration when the brakes are released is brisk, even with 2 average people and 58 litres of fuel. At MTOW of 490 kgs, a safe rotation at approx. 45-50 knots is achieved after approx. 50-60 meters, with ROC settling at just under 900 fpm. Rate of climb with the 618, one POB and full fuel showed in excess of 1100 fpm at a climb speed of 45-48 knots.

After transition into straight level flight, and power reduced to 5400 RPM, a genuine indicated airspeed of 65 knots is maintained at this power setting, which the GPS proved to be correct. I have found over the last few years ferrying a lot of X-Air’s around Australia that the difference between the 618 and the 582 powered versions in cruise is almost negligible. I think the X-Air is quite sensitive when it comes to changes in propeller pitch, especially with the commonly used Brolga Props, a different set of pitch blocks can easily add those few more knots in cruise performance if required at the expense of some climb performance.

There are also a few Jabiru powered X-Air’s in the country which I have flown and besides a minor saving in fuel consumption I can see no real benefit in the much more expensive engine costing more than twice the price of the 582 Rotax.

Some people may argue the 2-strokes reliability, however a well maintained, modern 2-stroke is by no means as unreliable as their reputation used to be and the difference in fuel consumption is also not really an issue since almost all of the small 4-strokes, such as Jabiru, 912 etc., will burn around 20 litres/hour in cruise configuration when fitted to an aircraft like the X-Air.

Control response of the X-Air is excellent, with direct response and light stick forces in all 3 axis the X-Air sports a roll rate from 45 to 45 degrees of less than 3.5 seconds. There is a noticeable adverse yaw tendency if you turn with just the aileron but this however is easily encountered with the use of its highly effective rudder, the X-Air loves using the rudder.

Stall characteristics are completely without any vices and the aircraft can in my opinion be classed as quite stall resistant. Reducing power to a fast idle of approx. 3000 RPM, the first sign of a departing airflow does not try to get your attention with a pronounced stick shaker until below 26 knots. By the time the nose actually gently drops there is no reliable reading on the ASI left to determine an accurate stall speed but my guess with the GPS is its well under 25 knots. At MTOW, or ferry weight, most X-Air’s stall around the 26-28 knots IAS and there are also no nasty characteristics noticeable in any configuration. Even with stick fully back, the aircraft does not fully stall and as soon as the nose lowers there is enough airspeed for the X-Air to un-stall itself and it just keeps flying. I guess this is one reason why the X-Air is such a popular choice with new pilots as their first plane.

The X-Air is not really demanding when it comes to approach speeds and an IAS around 35 knots in calm conditions up to 55-60 knots has been successfully tested. In my experience I find with 2 POB approaching at just under 50 knots seems to be most comfortable with absolutely no tendency to “balloon”. With only one POB 42-45 knots seem to be right on the mark, the X-Air is probably the most controllable and stable plane I have ever flown on approach and flare, I have managed to safely and with full control land the X-Air with up to 30 knots of true cross wind and although I don’t want to push it I would guess it could take more.

Except for one recent episode where a quick landing into a wet paddock was a wise decision after the engine sounded a bit odd right after take off I must say I never had a bad landing or a bouncer in any of the X-Air’s I have flown and I can safely say that if you really bounce it on the deck for whatever reason or actually really feel a “hard” landing you probably have nothing to worry about more than your mates who have seen the stuffed up landing. The X-Air’s landing gear is exceptional and there is no other way of putting it. It will not bounce and will take a tremendous shock even during a bad landing before anything brakes or bends.

It would be a bit too much to call the X-Air a serious cross-country machine with its modest 65 knot cruise, but for what this plane has been designed to do it is certainly the leader in its category, there are plenty of mega-bucks speed demons available if you need to regularly fly huge distances. However having said all this I have flown hundreds of cross-country hours in the X-Air, in all sorts of versions – with wheel spats, enclosed with the optional cabin doors or open, 2-stroke and 4-stroke powered, standard and optional long range tanks, alone or with company during long flights, and there is virtually no place it couldn’t get to, even as a bar bones standard version, it is a pure pleasure to fly and still gets you from Brisbane to Narromine in less than a day, and Brisbane to Melbourne can be also done in two days and you even get to enjoy the scenery on the trip.

As for costs and building skills, I built my first X-Air several years ago before GST and I managed to get my plane airborne with the second hand 618 for just over $20,000. Today even with GST and fluctuating exchange rates I see from the X-Air web site it will cost under $17,000 for the complete airframe kit; on top of this you need to purchase an engine, instruments and propeller and any other goodies like GPS and radio etc..

The X-Air is still a highly attractive aircraft for anyone who is looking for an aircraft that is easy and fun to fly, economical to operate and maintain, does not require an extra mortgage for the initial purchase and also gets you to places when you want it to. The aircraft undergoes continual development and there have been quite a few changes from the original aircraft I purchased 5 years ago, the latest ones I have flown have larger brakes, a wider entry to the cockpit, luggage racks and a few subtle changes which make the plane the complete package.

If you are concerned about building it yourself you shouldn’t be…. Anyone who is capable of simply putting nuts on bolts can assemble the X-Air aircraft from the kit. For other things like wiring, instruments and engine issues X-Air Australia has a phone in Builder’s Assistance Service under the supervision of an experienced person. Additionally after the aircraft is completed it can also be test-flown and delivered to almost any location within Australia by the people at X-Air. They have also just finished a DVD and video on building the plane which takes you step by step through the process from start to finish.

Am I glad I brought an X-Air ??  I sure am, I would have another one in a heartbeat if time allowed, for now I seem to have built up a reputation for flying them all over Australia and each time the phone rings I always think… where to now….  It’s all good fun in a fun aircraft.

By M. Mayerhofer Phone 0407 375 952