Moving (Down) To Light Sport

Even experienced pilots will need transition training when moving to an LSA, thanks to different wing- and power-loading.

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Are you an experienced pilot with a light sport aircraft (LSA) in your future? For many of us, LSAs answer the need for a lower-cost option as we seek to continue flying even as the expense of doing so keeps rising. For others, an LSA is a way to scale back to the type of flying that attracted them to aviation in the first place. Yet other rated pilots see the medical self-certification of sport pilot rules as a way to keep flying longer, perhaps after becoming ineligible for an FAA medical certificate, while accepting the rules limit us to flying LSAs.

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Regardless of your motivation, moving from “traditional” airplanes to LSAs may be a little more involved than you’d expect. For example, what are the design and engineering issues that make LSAs handle differently than larger airplanes? What’s the safety record for pilots moving “down” to light sport? And, is there anything we can do to better manage the differences?

What’s a light sport?

To meet the LSA definition (and therefore be flown by a pilot exercising sport pilot privileges), an aircraft is limited to, among other things:

• Carrying no more than two people;

• 120 KCAS maximum cruise speed; and

• 1320 pounds maximum gross weight (1430 pounds for seaplanes/amphibians).

It’s the weight limitation that gets many transitioning pilots, especially those who are “downsizing” from a high-performance single or a light twin. Weight drives wing and power loading, and consequently performance, especially at the low-speed end of the spectrum. And that’s where most light sport mishaps occur—at low speed, on takeoff, while landing or in the traffic pattern. Why is airplane weight such a factor in LSA transition training?

Wing Loading

Wing loading is the aircraft’s current weight (usually expressed in pounds) divided by its wing area (usually in square feet). Although wing loading is generally used in engineering stress analysis, it has practical application in aircraft handling as well.

An aircraft with a relatively low weight and a large amount of wing (“low wing loading”) will be able to generate enough lift to exceed its weight at a relatively low speed, It also will climb at lower speeds, or more steeply than a similar design at a higher weight; descent angles will be less for a given speed and/or power setting.

What’s this mean? Low wing-loading aircraft will be airborne at low speeds, and tend to float on landing if speed is too great. A crosswind’s effect will be greater on the lighter aircraft at these lower speeds, too. If they aren’t designed properly, controls may not be as effective during takeoff or landing as in traditional airplanes.

It will almost certainly require more deftness on the controls in lighter crosswinds, and will be less forgiving of trying to “plop” or “drive” it onto the runway, like some pilots do in heavier airplanes. Low wing-loading also results in reduced stability and a greater tendency to be bounced around by turbulence.

Wing loadings for several popular LSA and standard category airplanes are listed in the sidebar on page 17. As you can see, the sample LSA designs have wing loadings similar to a Cessna 150, somewhat less than the Piper Cherokee 140 and Cessna 172, and much less than airplanes like the A36 Bonanza and Cessna 310…types usually considered to be very stable, and similar to those owned by many pilots considering a move into light sport. If you want to prepare for an LSA before you buy and one is not available for rent, find an instructor teaching in a Cessna 150 to get reacquainted with the effect of winds and thermals on control and stability.

Power Loading

Power loading is the aircraft’s weight divided by the engine’s horsepower. The lower the power loading, the more acceleration and climb capability exists. The sample LSAs in the table at right share the same power loading because they all have 100-hp engines—some Rotax, some Continental—and are all artificially limited at the same maximum weight to meet light sport rules.

The light sport power loadings are closer to an A36 Bonanza than most traditional training-type airplanes. With their light wing loadings, an LSA can get airborne at a relatively low airspeed and is likely to float at low speeds on landing with anything more than idle power. Both are situations where it will take greater control by the pilot to compensate for crosswinds and turbulence. This is part of the reason pilots need adequate practice to transition to light sport aircraft.

The Transition Mindset

It’s a common attitude in aviation that experience in one type of airplane equates to ability to fly smaller or less-powerful types. Get a rental checkout in an FBO’s Cessna 182RG, for instance, and you’d expect rental privileges in its C-172 and C-150 with little or no additional checkouts.

I’ve spoken several times with Jim Lauerman, president of Avemco Insurance, about the safety record of light sport aircraft among pilots transitioning from traditional light airplanes. Avemco is one of the biggest insurers of LSAs, so it has some of the best information about the track record compared of these transitioning pilots.

Avemco’s initial experience with LSAs (over the first two years following the class’s introduction) was that the accident rate was “about twice as high” as the rest of Avemco’s lightplane business. As expected, tailwheel-equipped LSAs had a worse record than tricycle-gear models. The severity of accidents—how bad they were in terms of injury and airplane damage—was 48 percent greater in LSAs than in Avemco’s average policy.

“A deeper analysis shows the issues we discovered are not that different from any new aircraft type,” Lauerman wrote in 2008. He concluded that pilots and instructors “continue to underestimate the quantity and quality of transition training necessary to go from [traditional] general aviation aircraft” to LSAs. “The evidence for this is that many…losses were very early on in the ownership experience and sometimes included a CFI onboard the aircraft.” Most losses were caused by “the classic loss of directional control issues that plague all of GA.” Pilots “are ‘driving’ these aircraft rather than flying them using frequent small control inputs around all three axes.”

Pilots transitioning from traditional airplanes had far more accidents than pilots who learned to fly in LSA. They were “a perfect storm combination of lacking directional control skill in lightly wing-loaded aircraft.” It was a case of pilots “believing that checking out in these ‘simple little aircraft’ couldn’t be that big of a deal. The combination of needing training but believing none was required is not a good one for general aviation safety.”

Subsequently, Avemco has stipulated a minimum five-hour checkout with an instructor in make and model before insuring a pilot as pilot-in-command. This checkout, regardless of the transitioning pilot’s prior experience, has significantly reduced the accident rate among Avemco’s LSA customers.

Going Glass

If you’ve been flying for many years, your transition “down” to light sport may include your first exposure to the most advanced avionics you’ve ever flown. Most light sport designs have full glass cockpit primary flight displays (PFDs) and multi-function displays (MFDs) linked to GPS receivers—partly because the newest aircraft generally have the newest avionics and partly because glass cockpits are lighter than traditional instruments and the systems powering them—helping meet the 1320-pound restriction. Even the “Cub clone” LSAs usually have some form of cockpit glass.

While you’re busy transitioning to the performance and feel of these very light aerial vehicles, you’ll at the same time be learning the operation of some pretty sophisticated avionics. And since the avionics are not “certified,” they may not share the operating logic of even the technologically advanced aircraft you may have previously flown. You’ll need time to learn to use the panel without being distracted, in addition to learning the basic flying task of low wing-loading, low power-loading LSAs.

Engine Ops

There are two main engine types used in LSAs: the Rotax 912 and a special, lightweight version of the Continental O-200. Both are rated at 100 horsepower at maximum, sea-level power. If you’re flying the Continental, then engine management will probably be old hat—it’s the same engine that powered the ubiquitous Cessna 150, and is operated like just about every other small carbureted engine. Just remember the carburetor heat, especially if you’ve spent a lot of time with fuel-injected engines and have forgotten about preemptively avoiding carb ice.

The Rotax engine, however, is normally run between 4900 and 5100 rpm in cruise, with the propeller spun down at “normal” levels (2000-2700 rpm) by a reduction gear unit. Maximum takeoff power is 5800 rpm for five minutes, with maximum continuous power at 5500 rpm and idle at around 1400 rpm. Starting, stopping, cruise and emergency procedures are unique (compared to most traditional airplane engines), and some pilots take a little time adjusting. It’s not “better” or “worse,” it’s just different…and differences are why we need time and experience to make an adequate transition and instill new habits appropriate to fly the aircraft we are flying.

Handling the Change

If wing loading and power loading were the only differences between LSAs and traditional light airplanes, then any experienced pilot with good stick-and-rudder skills should be able to strap into one and fly it safely without a transition. Recall, however, that part of the appeal of light sport is the innovation that has been brought swiftly to market by eliminating the need for type certification under FAR Part 23.

Part 23 airplanes—and the vast majority of our airplanes that were certificated under the earlier Civil Air Regulation Part 3 (CAR 3)—must meet minimum standards of control stability, feel, responsiveness and authority. Light sport types are not certificated airplanes at all, but are merely compliant with the much-less-stringent industry standards of ASTM International.

Most light sport aircraft are not as stable, nor are their controls as balanced or responsive, as the airplanes experienced pilots are used to flying. And the control feel and responsiveness may vary dramatically from one LSA type to another. Again it’s not a matter of “better” or “worse,” except in the opinion of the pilot, but it most certainly is a matter of “different” for the pilot transitioning into LSAs.

Put bluntly, an LSA may not react the way your prior experience leads you to expect, no matter how thick your logbook. Muscle memory (instinct that results from your past experience about what you do with your hands and feet to react to a given change in airplane attitude) will have to be overcome in some instances—you may need to unlearn some things to fly light sport safely, smoothly and efficiently.

In short, it will take time for you to learn just how to control an LSA, in addition to learning its reaction of a low wing-loading, low power-loading aircraft to crosswinds and turbulence, especially close to the ground where margins for error are slim.

Resisting Temptation

Lastly, although some LSAs are tube-and-fabric throwbacks, many are sleek, bulbous designs with wide bubble canopies and stick controls. In other words, they look like little fighters…but they’re not. You might be tempted to fly rolls and loops and high-speed pull-ups, but before you do, remember they are not stressed for aerobatics; in fact, to meet the restrictive light sport weight rules they are built to a minimum strength. This is not to say they are unsafe—they’re safe, when flown within their intended flight envelope. Just don’t do anything you wouldn’t (or shouldn’t) do in a Cessna 172.

Whether to minimize the cost of flying as a way to experience a new aircraft (as opposed to flying a traditional type in a fleet that averages over 40 years old), because you want to avoid the requirement for an FAA medical certificate, or just to return to the fun flying that attracted you to aviation in the first place, you may find an LSA in your future. Light sport aircraft are exciting and safe aircraft, but the conventional wisdom that the ability to fly a larger airplane equates to competence in anything smaller just doesn’t ring true, especially when moving down.

History and the insurance record shows you’ll need to budget plenty of quality instructional time to learn the aerodynamics of these very light aircraft, and time in make and model to develop new habits as you pick up the different and sometimes unique control requirements of individual LSA designs.

Tom Turner is a CFII-MEI who frequently writes and lectures on aviation safety.

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