Synthetic vision for sports aircraft
Flight Design introduces synthetic vision, in the form of Dynon’s SkyView, to the factory-built Light Sport Aircraft
Had you told me a decade ago that a simple, 100hp light aircraft would soon be available with digital autopilot, triple GPS receivers, dual independent Air Data Attitude and Heading Reference System (ADAHRS) computers and ‘synthetic vision’, I wouldn’t have believed it?yet here at Sebring, Florida I was about to fly one. The first Flight Design aircraft I flew was the CT-SW, way back in 2005. Although delightful to fly, few would dispute that it was overly sensitive in pitch, particularly for less-experienced pilots. Flight Design addressed this issue with the CT-LS (LS for Light Sport) which boasted myriad improvements, including the use of composites instead of spring aluminium bars for the tricycle undercarriage, additional rear windows, wider baggage bay doors, slightly longer ailerons, winglets and a redesigned ventral fin. Most significantly, it was much better damped in pitch, being 35cm longer. The aircraft was a huge success, and remains America’s best-selling Light Sport Aircraft. However, Flight Design is not the sort of company to rest on its laurels, and the machine that I was about to fly had been improved still further. Tom Peghiny, President of Flight Design USA, briefed me on some of the changes: to reduce control effort, the aileron control system has been completely redesigned. (I recall the 2008 version having high break-out forces, but had attributed this at the time to the aircraft’s newness.) Other improvements include a redesigned fuel vent system, reinforced main undercarriage bulkhead, a redesigned rudder centring device and rudder stop system, a tow bar connection, light weight lithium-ion starting battery, an integrated oil cooler thermostat and a larger and more effective Whelen LED landing light. Inside the cabin the instrument console (Flight Design calls it ‘the mushroom’) is larger and the cabin lighting has been improved. To satisfy of the notoriously parochial US market, the LS is now fitted with ‘made in the USA’ wheels, tyres and brakes?and a Sensenich propeller. However, the real changes are in the instrument panel: the aircraft I was about to fly has an avionics suite that wouldn’t look out of place in an airliner. Taking centre stage is the amazing Dynon D-1000 SkyView system. This features twin ten-inch screens, which display information from a fully integrated digital system, fed from dual redundant ADAHRS and two pitot probes. Between the two screens is a Garmin 696GPS loaded with all the usual goodies, such as TIS anti-collision, terrain, XM weather, music etc, a Garmin SL40 Comms unit and GTX 330 Mode S transponder. This provides the TIS information for both the representation of traffic on the 696 (vertically), and horizontally on the SkyView. The test aircraft also featured a TruTrak CT Pilot IIVS autopilot (although I believe that the 2012 CTLS has a Dynon autopilot). Other improvements include a PS Engineering PM3000 stereo intercom, and both LEMO and standard headset jackplug sockets. Now, you may well think that’s a surplus of digital delights, but in fact the aircraft has incredible levels of redundancy, as the dual SkyView system means that it actually has no fewer than three GPS units on board, powered by three independent backup batteries. One further interesting design feature is that there are no pitot lines running into the cockpit, as the ADAHRS units are located in the wings. Of course, the real story is synthetic vision, and with such an extraordinarily powerful system, the easiest way to learn how to use it is on the ground. Before I went flying, Tom introduced me to Eric Crump at the Gleim stand. Here, the whole instrument panel was displayed on three large computer screens, and it really was extremely useful to be able to concentrate on the avionics without having to fly the aeroplane at the same time. Although the Gleim simulation doesn’t actually replicate SkyView’s synthetic vision mode?it’s just too complex and detailed to run through the sim software?it is very useful for simply learning the basics as well as being an extremely cost-effective way of being introduced to the SkyView. (I should add that Gleim sim actually reproduces the performance and handling characteristics of the CT-LS well, although I felt that perhaps it could’ve used a bit more damping in yaw.)
Not your grandfather’s CT-LS Out on the flightline, I could see that this really wasn’t your grandfather’s CT-LS as soon as the instrument panel lit up. One feature that I liked from the start is that it is possible to use any computer-based flight planner that supports the GPX file format to create really quite sophisticated flightplans, with multiple legs and waypoints, from the comfort of your home. It is also easy to pan around the map and get detailed airport, airspace, and terrain information for areas away from the aircraft’s current location. If for some reason you have to amend the flightplan en route, this feature is a real boon, as you can start thinking and planning your approach and landing while still thirty to forty minutes out. To assist you in this, airports, VORs, NDBs, other fixes, and even arbitrary lat-long locations can be added readily as direct-to or flight plan waypoints. To do this, simply push sideways on the map joystick to activate panning, and the cursors lat-long location automatically appears on the screen. While panning you can zoom in to see more detail, or out to gain a wider perspective. A useful by-product of this feature is that you can more easily move the cursor quickly to a distant location?and if you the press ‘Direct To’, it gives you precise digital guidance to the cursor’s location. Alternatively, if you press ‘NRST’ (nearest) a list of all the airports and navaids closest to the cursor is shown. This system makes diverting to a new alternate a cinch. Another neat feature is that the system can also be configured to provide ‘turn anticipation’ between flight plan legs. This means that the SkyView commences turn guidance in advance of a waypoint, ensuring that you don’t inadvertently overshoot the next leg. The stick-and-rudder contingent may scoff and sneer at this feature, but remember that a fast cruise in the CT-LS at, say 7,000ft is around 116kt. Throw in a tailwind of 44kt?not uncommon at this altitude?and your speed over the ground is 160kt, or more than three statute miles a minute Perhaps towards the end of a long flight, a little ‘turn anticipation’ might just come in handy after all… Even taxying out was interesting, as the 696’s SmartTaxi display clearly showed our progress along the taxiway. As I lined up on Runway 18, the view over the nose and the image on the screen were identical, and as we climbed out Lake Istopoka appeared and this was faithfully rendered in every detail on the SkyView’s big screen. Loath though I am to fill this report with superlatives, I have to say that it is almost impossible to appreciate just how amazing this piece of kit is, until you fly with it. The amount of detail that is displayed is really quite astonishing, and I assumed that our aircraft had the terrain database for either Florida or possibly the East Coast loaded. In fact, it contained the complete maps of North America. Furthermore, Dynon Avionics and Jeppesen have entered into an agreement to provide Jeppesen NavData and obstacle services for SkyView. This agreement will allow the pilots of aircraft fitted with SkyView avionics Jeppesen navigation data for any region on Earth, including airport information, runways, navaids, and Com and Nav frequencies.
Cries ‘wolf!’ at private airfields Circuit work at nearby Placid Lakes airport revealed one of the test aircraft’s very few shortcomings. As the airfield is private, its details are not in the 696, and consequently as I turned final this generated increasingly insistent warnings from the Garmin about ‘sink rate’, ‘terrain’ and eventually the instruction to ‘pull up pull up,’ as it did not know that we were perfectly aligned with the runway that was immediately in front of us. This could potentially be very distracting, and while I’m sure that these warnings can be cancelled, neither demo pilot Kent nor I knew how! Conversely, on the SkyView it is very easy to cancel an alarm: when one of the main buttons flashes red, you simply push to acknowledge. This being central Florida, the lack of significant terrain meant that I couldn’t see how well SkyView depicted hills and mountains, but the myriad lakes and masts were accurately rendered in astonishing detail. A few days later I flew the LS again, down to the giant Lake Okeechobi. With some of the earlier Dynons, readability was sometimes an issue?especially in bright sunlight. However, a series of 360s revealed that the SkyView’s screens are much brighter, while the larger fonts and improved graphics make it much easier to read. I also noticed that the ‘transparent graphics’ have been improved (to increase overall visibility) and that the navigation annunciation adjacent to the HSI has been moved to good effect. Thus far I have only described the PFD, but the MFD on the other side of the panel is equally capable. On our aircraft this showed: rpm and manifold pressure; fuel quantity, flow and pressure; volts, amps CHTs and EGTs. However, remember that the unit is configurable, so it can also (for example) show undercarriage, flap and trim position, power as a percentage, carb and cabin temperature. Should you add the VP-X electronic circuit breaker option, this shows device status, current draw, faults, voltages, alternator status, overvoltage faults etc. Dynon claims that the map user-interface has been optimised to be the fastest and most intuitive available, and I must say I was pleasantly surprised at how quickly I picked it up. I am sure you will now ask “How much does it cost?and can I install a SkyView in my PA-28?” Unsurprisingly, such an extensive avionics fit does not come cheaply. As installed in the test aircraft, it amounted to $11,335 ?but that does include the upgrade to the Dynon SV-261 Mode S transponder (which allows the TIS traffic). If you want VP-X, the software licence is an extra $275. As for sticking a SkyView in your Piper or Cessna, sadly not: the CAA requires the avionics fitted to a standard-category light aircraft to be signed off with a TSO (Technical Standard Order). This confirms that the materials, parts etc have met a ‘minimum performance standard’. As LSA machines conform to ASTM, it is not necessary to use TSO-approved avionics – and as gaining a TSO is both costly and time consuming, manufacturers such as Dynon can improve and enhance their products much quicker and cheaper than the manufacturers servicing certificated market. The downside is that you can’t use a Dynon in a standard-category light aircraft. Of course, in most respects, a modern LSA such as the CT-LS actually out-performs a ‘classic’ or ‘legacy’ GA two-seater on just about every level. Indeed, aircraft like the CT-LS have matured exponentially. These machines are not toys, but practical, viable machines for going places fast and efficiently: At 4,800rpm and 5,000ft the LS will true out at an impressive 112kt for a fuel flow of around 18lit/hr. Pull the power back a bit more and at 100kt TAS the LS can cover an astonishing 1,000 nautical miles. More impressively, this is achieved at a perfectly respectable 100kt. When you fly 500-600 miles you can pass through several different air masses and weather systems. The XM weather keeps you fully apprised of any weather developments, and if you do need to make an unplanned diversion, the SkyView makes it all very easy. “For VFR pilots who want to do real cross-country flying, the information and redundancy of the SkyView package is invaluable,” says Flight Design’s Tom Peghiny. “I can imagine a pilot at the end of a long cross-country flight coming to the destination late, in marginal VFR conditions, liking the extra situational awareness, finding the runway and avoiding obstacles. When you combine the SkyView with the XM weather and traffic display on the Garmin 696 or 796 it is a very capable panel”
Eliminating uncertainty We’ve all endured exactly the sort of flight that Tom described. It’s late, you’re tired, and flying west towards an airport you’ve never been to before and into a setting sun and hazy sky. Of course it’s legally VFR – if you could head east the viz would be really quite reasonable. However, the heading required to track to your destination is 275 and let’s be honest – you can hardly see past the spinner. To add to your unsettled feeling, you know there’s a tall mast close to the field and controlled airspace nearby... With the SkyView, all the uncertainties and ambiguities go away?it’s that good. As I said at the outset: ten years ago, I would never have thought that a 100hp fixed undercarriage fixed-prop two-seater would be fitted with avionics that would shame many airliners?yet I’ve just flown one. So yesterday’s dream of the future is today’s reality. What might our GA instrument panels look like in 2020? I’m not even going to try to predict that!