www.kitplanes.com & www.facebook.com/kitplanes6 KITPLANES November 2016

The BD-17L has much in common with the original BD-1.

By PAUL DyE

A long time ago, nearly 50 years as close as I can figure, Jim Bede Sr. was a young aeronautical engineer who conceived a simple aircraft for the masses. The air-plane, known as the BD-1, required few unique parts to assemble, had honest handling qualities, and could be mass produced in large numbers at low prices. As some may remember, it was the even-tual prototype for the certified American Yankee, later to become the Grumman Yankee, Trainer, and TR-2. The design

grew into a four-place version, the Grum-man Traveler, which then morphed into the Cheetah and Tiger, all of which have a fiercely loyal following of pilots and owners to this day.

That one design prototype produced many successors and thousands of air-planes—yet utter simplicity had still not been achieved. Bede still searched for an airplane that anyone could own—and build—and that required little to no unusual fabrication skills.

That search continued for decades, through many models and configura-tions. In his quest, Bede employed many young engineers, fabricators, and pilots who went on to do stellar things of their own in aviation. Perhaps you’ve heard of Burt Rutan? He’s a Bede alumni. Airshow pilots Corky Fornoff and Bobby Bishop? More associates of Bede in his Newton, Kansas, days.

The BD-1 was followed by an endur-ance record-setter, a one-off airplane

Miniature Yankee

Photos: Richard VanderMeulen and Paul Dye KITPLANES November 2016 7

designated the BD-2. The -4 followed, then the famous flying egg, the BD-5. Many more digits joined the ranks of his design catalog until he reached the high teens, and the BD-17 was born, a return to the roots of simplicity, com-pact design, and easy construction. This may well be the airplane that many Yankee pilots dreamed of when looking for a simple airplane with enough zest to satisfy, but without the burden of an extra seat. After all, fighter pilots usually fly alone, don’t they?

The BD-17 strikes one very much to be a flying jet ski. Yes, there are many larger boats available to the fisherman or pleasure-boater, but if you just want to go fast and have fun on the water, it is hard to beat a single-seat jet ski. The BD-17 is much the same, a single-seat

airplane that you strap on and—burning just a couple of gallons an hour—go and explore the neighborhood from the air.

Always EvolvingThen along came the Light Sport rules. The lure of an airplane that you could build cheaply, had benign stall speeds, and that could be flown without a medi-cal was more than Bede could resist. In fact, it had been his dream for much of his life. The -17 looked like his ticket into the LSA world, but it needed a few modifications first.

The BD-17 became the BD-17L when the LSA rules were written, the “L” des-ignating the long wing used to reduce the stall speed to that required to meet the new regulations. The original -17 used a shorter wing, which had a higher

stall—and therefore—higher takeoff and landing speeds. Of course, with increased span comes reduced roll rates, but that was the compromise made to fit into the new LSA category.

Traditional Bede ConstructionThe BD-17 is pure Bede when it comes to construction. The fuselage “canoe” is made up of aluminum honeycomb pan-els for the bottom and sides. These are bonded together, with the corners rein-forced by aluminum angles. The bond-ing in the early Bedes required baking in order to cure; the new process uses a two-part adhesive that is cured at room temperature, making it practical for the homebuilder. The turtledeck of the fuselage is a curved sheet of aluminum with bulkheads added where required.

Simplicity has always been a mark of Jim Bede’s design work. Wingskins are simply folded rectangular aluminum sheets.

The aluminum honeycomb construction of the fuselage is apparent at the canopy rails and behind the seat. This has proven to be very strong in previous Bede designs.

The swing-back canopy on the BD-17L shows the heritage of the design, as it looks very similar to the canopy on

the BD-5. The long wings allow the airplane to stall slow enough to qualify as an LSA.

The wings use the trademark tubular spar of the Bede designs, along with ribs cut from the same honeycomb used for the fuselage. The ribs are cut by Bede using a router—lasers or water jets won’t work because lasers melt the adhesive making up the honeycomb, and water jets tear the material to shreds. The ribs have a main hole in the center for the spar, so the ribs are threaded on, then spaced out to the required distance, squared up and glued in place. The trailing edge aligns the ribs and is fastened with adhesive and riveted clips. All adhesive in the wings is polysul-fide sealant, making a natural fuel tank of the wing itself. This is unlike the earlier

Yankee, which used the hollow tubular spar, limiting the total amount of fuel the plane could carry. Wiring and plumbing is added once the ribs are bonded to the spar, then the skins are wrapped around the substructure and adhered the same way—with polysulfide sealant.

Bede personnel use custom-made jigs to align the ribs and spars, and can build a wing fairly quickly. The limiting factor is the time it takes the adhesive/sealant to cure. When demonstrating the pro-cess, they could physically put the parts in place in a very short time, but the overall wing-bonding process takes about two weeks for a set. If a buyer chooses the

quickbuild option, Bede will assemble the wings and fuselage canoe on their jigs in Florida and ship it out that way. The customer can choose to come to their facility and participate if they like.

Tail surfaces are likewise built up using ribs and skins bonded with adhe-sive, but they do use a few rivets along the trailing edges, mainly to keep things in position while the adhesive sets. The standard kit comes with the tail surfaces assembled, saving considerable time that the builder would use to construct jigs.

The landing gear on the -17 is a con-tinuous hoop from right to left main-wheels, bolted to the fuselage and wing

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The factory jig for the BD-17L fuselage provides a clamping force to hold the few elements together as the adhesive sets. This assures a straight and true assembly.

Wing ribs for all the available Bede designs are cut from aluminum honeycomb sheet.

The jig for BD-17L tail surfaces clamps the skin and ribs together as the adhesive cures.

Modern two-part sealants/adhesives are used to create the various structures that form the BD-17L. This makes homebuild-ing possible. Earlier Bede bonded struc-tures took factory equipment to cure the adhesives properly.

center section. The nosegear fastens to brackets on the firewall, and uses a rub-ber donut between the rudder pedals to absorb shock. The nosewheel is full cast-ering, and ground steering is performed with differential braking.

Overall, the airplane is simple, strong, and looks easy to build—exactly what Jim Bede was looking for.

The CockpitThe cockpit is fairly roomy for a single-seat airplane and the panel space more than adequate for any reasonable instru-mentation such a light DVFR airplane would require. The demonstrator uses

steam gauges for primary flight instru-mentation and has a mount for an iPad mini in the middle for use as a moving map. The canopy is classic BD-5: Two hinged supports on the sides and a sin-gle arm in the rear allow it to swing up and back in a relatively level attitude. It swings forward and down to close and is latched with a single latch in the center. This works quite well, but I suggested that a stop be placed on the latch to pre-vent it swinging all the way around. As it is, the handle can swing forward when unlatched, catching under the wind-shield bow and preventing the canopy from being opened.

The controls are a mixture of the con-ventional and the unique. The throttle, flap, and trim levers on the left side of the cockpit are just what any pilot would rec-ognize, along with the rudder and brake pedals. The side stick over on the right is more of a mystery to most. Angling out of the side console, it is a small-throw stick that works in the conventional manner—but you fly with just your hand, not your whole arm. In fact, it is better to think in terms of flying with just your palm and fingers; moving the entire wrist might be a little too much.

KITPLANES November 2016 9

Wing assembly is done on a jig that holds the tubular spar. Ribs are fed onto the spar, then spaced using the jig that positions the trailing edges.

With the ribs squared to the spar and inserted in the trailing edge fixture, adhesive is applied to bond the substruc-ture together before installing wiring and plumbing and bonding on the skins.

The panel in the BD-17L is quite spacious for a small, single seat airplane. An iPad fits in the center mount, but the airplane has plenty of room for all required flight instruments without it. The side stick makes for an uncluttered cockpit and works well, once the pilot adjusts to it.

There is plenty of room in the BD-17L cockpit for the modern human being. Seat adjustment must be done during construction or with cushions, a conse-quence of the simple design.

Some may be bothered before they fly it, with the fact that when the ailerons are neutral, the stick is angled about 45 degrees from vertical (unlike a nor-mal center stick). Amazingly, once you are flying, it takes about a nanosecond for this concern to go away because we adapt that quickly and realize that neu-tral is sort of an arbitrary concept.

There are no seat or rudder-pedal adjustments, but fortunately I am about average in height and propor-tions, so everything fit fine. Like most homebuilts, adjustments can be made during construction if needed, and cushions can be used to fix fit issues once the airplane is flying.

Flying the BD-17LClimbing into the -17 isn’t hard; it’s very typical for a canopied airplane that requires you to lower yourself into the seat by holding onto the longerons. The cockpit is roomy and offers plenty of space for today’s-sized adults.

The canopy latch can be opened from inside or out. It was just a little finicky to latch because the new canopy seals installed on the demonstrator made it hard to pull the canopy down to its seated position. A little tug makes it easier to start the latch process, and then the canopy pulls down easily. If the latch is not held in the right position, it can prevent the canopy from opening as it swings all the

way around and blocks itself on the wind-shield. This is something that Jim Bede’s son, Jim Jr., has added to his list of things to work on for future improvements.

The engine starts easily, and has a very wide rpm range, so I wasn’t surprised that I had to open the throttle quite a bit. Those used to Lycomings and Con-tinentals that have an rpm range from idle to full throttle of less than 2000 rpm will have a little getting used to when working with the small, high-rev-ving engines typical of most LSAs, but you can’t be afraid to move that throttle to get the power you need.

Taxiing the airplane is done with differential braking and a swiveling

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The flap lever is low on the left side of the cockpit and allows four flap positions. Full flaps does not lower the stall speed by more than a couple of knots.

The canopy latch has internal and external handles, and now has a stop to prevent it from swinging around and blocking the canopy opening when unlatched.

KITPLANES November 2016 11

Jim Bede Jr. took over running Bedecorp a few years ago, when his dad was ready to phase out of the business. He runs a successful construction company in Ohio, and wanted to keep his father’s designs and airplanes alive, now especially since Bede Sr. has passed away. Bedecorp now has a facility in Fort Pierce, Florida, with a few employ-ees who produce the kits for the BD-17 and BD-4. They can and do build quickbuild components and can build a set of wings in two weeks—much of that time devoted to curing. The tooling they have to produce these components makes things much simpler, and most customers take advantage of the quickbuild option—where the primary structure is already assembled—or take the time to travel to Bede’s facility to help put the components together using the factory tooling.

Like many kit companies, the operation is small, but the people are committed. Friends come and go throughout the day, some stopping to lend a hand on a maintenance effort, some being consulted for their aviation expertise on various design or construction issues. Over in one corner of the hangar is a row of BD-5 parts—fuselage tubs, wings, spars, and tails—that were purchased from former builders. What is Bede going to do with them? He wasn’t really specific about that; it just seemed like this was a better place for them than being turned into wind T’s or lawn ornaments. Bedecorp’s test pilot has his own BD-5 there, as does Bede Jr.—both propeller models. Neither is in flying condition, but it is just a matter of time, according to them.

Modifications are still being made to the established designs: the BD-4 and the BD-17L. The BD-4 is now available as the “C” model, with a wider fuselage and more capacity (KITPLANES® will report on that in an upcoming article). Engineering changes are still being made to both designs, as noted in an email we received soon after our visit, stating that they had done some work on the elevator linkages to make the side stick less sensitive in pitch, and more harmonious with roll. We look forward to giving the modified air-plane a try the next chance we get.

Jim Bede Jr. says that he has no intention to close up shop and end the business, so long as he has employees who want to continue the projects in hand and customers are still asking for his father’s designs. Although not as popular as they once were, they still get interest, and kits are still sold—an enduring legacy to a lifetime of work by Jim Bede Sr .

—P.D.

Bedecorp—a Family Legacy

Jim Bede Jr. is passionate about continuing his father’s legacy and keeping Bedecorp alive. He shares his time between the Fort Pierce, Florida, location and his construction business in Ohio.

nosewheel. The company airplane I flew had a problem with the left brake—it felt like a glazed pad and made it very difficult to turn left. This was probably unique to the airplane being flown, and the factory sent me a note a few days after I flew it saying they had overhauled both braking systems and everything is back to normal. I expected that, for almost all Bede air-planes steer in this fashion, and so long as you keep them in good shape, they drive around on the ground just fine.

On the day I flew the -17, it was bad enough that I planned all turns so that they could be made to the right if neces-sary. However, this is really a low speed issue, as once you have 15 mph of airflow over the tail, the rudder becomes effec-tive, and steering is done with aero-dynamics. The rudder throw is pretty small, but controls the airplane well. It should also be noted that the vertical tail is fairly large and can lead to weath-ervaning in a crosswind, so keep those brakes in good condition.

Bedecorp has set up a transition train-ing plan for their single-seat airplane that involves taxi maneuvers on the ramp, fol-lowed by low- and high-speed taxi runs to help pilots become familiar with the side stick controller (see sidebar) and the sensitivity of the pitch channel before

committing to actual flight. Checking new pilots out in single-seat aircraft is always a bit problematic, especially when the design is billed as sporty, so it is good that Bedecorp is thinking about this. It would be great if they had a two-seat transition trainer to accomplish the task, but for now, good briefings and practice at lower speeds is probably prudent. In my case, I did some of the preliminary taxi work and then proceeded to flight, based on previous airplanes with similar controls that I had flown recently.

As I do with all airplanes that have swiveling nose- or tailwheels, I lined up carefully and ran about a plane length down the runway to make sure every-thing was straight before adding power for takeoff. Once I pushed the throttle forward, the airplane accelerated like you’d expect for a Light Sport machine. Anticipating the potential for overcon-trol on rotation, I let the speed build up a little over stall speed, then eased on just a little back pressure to raise the nosewheel. The airplane lifted off soon after with nary a bobble and climbed away with good performance.

As expected, pitch forces were very light, and thus the airplane is very responsive in that axis. It is much heavier in roll (compared to pitch), so

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Training pilots to fly a single-seat airplane is always problematic, and more so if the airplane is a Light Sport intended for new and inexpe-rienced pilots. Many Light Sport pilots are folks that have thousands of hours of flying time, of course, and they will have little problem if they have flown multiple types of airplanes in their careers. But for less experienced pilots who have never checked out in a new airplane without an instructor on board, getting through that first set of flights can be problematic.

Many kit companies are now taking transition training seriously, with many of them developing factory provided (or approved) training programs for their builders. This helps everyone—the new pilot, the company, and the entire Experimental community—by lowering mishap rates and keeping kit aircraft out of the news. Bedecorp has, interestingly enough, been on the front of this trend. In fact, they have been there for over 40 years.

Dating back to the days of the BD-5, Jim Bede Sr. recognized the problem of training people in his little egg-shaped single-seat aircraft. He solved the problem in a unique way—by building an articulated boom on the front of a powerful pickup truck and mounting an airframe (sans engine) on the boom. The truck would push the plane

(with student pilot installed) down the runway at flying speed, and the pilot could get used to the controls for roll, pitch and yaw—to the extent that the boom would allow. Jim Jr. told us stories of driving the truck, and how it frequently wore out front tires and suspension parts because of the forces applied to the suspension by the flying machine out on the nose.

Today’s aspiring BD-17 pilot need not worry about buying truck tires—but the company is serious about providing transition training, so there are few surprises when the pilot finds himself in the air in his new bird. The program exists as a multi-page checklist that starts out with a thorough preflight of the aircraft, the instructor signing off each step as the student learns the airplane. Not only does the student learn to preflight the aircraft, the one-on-one talk is a great opportunity for the instructor to pass on a great deal of detail about the airplane, how to work things, and what to expect.

Following a signoff in aircraft knowledge, the student straps in, fires up the engine, and motors around the Bede ramp at Fort Pierce, Florida. Starting out with simple braking, then progressing to oval patterns and finally, figure eights, the student get the feel of the brakes for steering and when the rudder becomes effective.

Transition Training—Solo!

Bedecorp Bd-17L Kit Price . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $25,900.00Estimated completed price . . . . . . .$35,000.00 with engineEstimated build time . . . . . . . . . . . . . . . . . . . . . . . . . . 400 hoursNumber flying (at press time) . . . . . . . . . . . . . . . . . . . . . . . . . . .4Powerplant . . . . . . . . . . . . . . . . . .HKS 700E 60 hp @ 6200 rpmPropeller. . PAC (Prince) P-Tip, 52-inch, 2-blade, fixed-pitchPowerplant options . . . . . . . . . . . . . . . . . . HKS, Rotax, Jabaru, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ULPower, 60–120 hp

AIRFRAMEWingspan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 ft 1 inWing loading . . . . . . . . . . . . . . . . . . . . . . . . . . .14.05 lb/sq ftFuel capacity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 galMaximum gross weight. . . . . . . . . . . . . . . . . . . . . . . . 950 lbTypical empty weight. . . . . . . . . . . . . . . . . . . . . . . . . . 525 lbTypical useful load . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 lbFull-fuel payload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280 lbSeating capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Cabin width. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 inBaggage capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 lb

PERFORMANCECruise speed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 kt @ 60 hpMaximum rate of climb. . . . . . . . . . . . . . . . . . . . . . . . . . 750 fpmStall speed (landing configuration). . . . . . . . . . . . . . . . . . 34 ktStall speed (clean) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 ktTakeoff distance (to 50 ft agl) . . . . . . . . . . . . . . . . . . . . . . 800 ftLanding distance (from 50 ft agl). . . . . . . . . . . . . . . . . . 1200 ft

Specifications are manufacturer’s estimates and are based on the configuration of the demonstrator aircraft.

not very harmonious. Don’t take the word “heavy” the wrong way, how-ever—compared to almost anything else a private pilot is familiar with, roll forces are still light—but there is some notable throw of the stick required to roll the airplane. It doesn’t take long to adapt to the lack of harmony, and with foreknowledge, the new pilot shouldn’t get into any trouble.

The rudder is light, better than many airplanes that I routinely fly. It’s not as light as pitch, but much lighter than roll. This particular airplane wanted to very slowly roll off to the right when flown hands off, but it was easy to compensate

and pull the low wing up with rudder (at the expense of speed). The visibility out of the canopy was good, as I find with almost all of the single-seat low-wings. Even though I was flying early in the morning, the local heavy flight school traffic was already appearing as I departed the airport for a local practice area, and it was easy to spot traffic as the tower called it out.

Leveling off in the practice area, the first order of business was some clearing turns to get the feel of the airplane and see how quickly it responded to control inputs. The airplane holds altitude in nor-mal turns surprisingly well, considering

the light pitch forces. Once trimmed, it stayed put with almost no back pressure. I tried progressively steeper turns in both directions, and roll control was positive, as was the roll stability. It tended to want to return to wings-level flight up to about 30 degrees of bank, was fairly neutral up to about 45 degrees, and then you needed opposite aileron to keep it from steepen-ing the bank beyond that—very normal for this class of airplane.

Next up was slow flight and stalls. Once again, the airplane seemed mild-mannered, with a mild break and no

KITPLANES November 2016 13

The free-swiveling nosewheel is typical of Bede’s tricycle gear airplane designs.

Once both the student and instructor are comfortable, it is time to head to the runway and do some 40-mph runs to get a better feel for steering with the rudder. After a few runs of this, it is time for nosewheel liftoffs, followed by braking to a stop. In this way, the student gets a feel for the side-stick controller—the major reason for the training program. Eventually, the student works up to their first flight, hopefully with a better feel for the sensitivity of the controls and ready to enjoy their time in the air.

Now, it should be acknowledged that what the student is doing is really what has been called “high-speed taxi testing,” and this is something that is known to be a double-edged sword. In fact, any time you head down a runway at more than a fast walking speed, you need to be ready to fly the airplane. Gusts can suddenly raise your air-speed above that needed to fly, or a student can get too much throttle in (or leave it in too long) and end up flying before they know it. If one isn’t ready for flight, they shouldn’t be operating near flying speed. But as in all things aviation, risks are always a trade.

Without a truck-powered simulator, there are few ways for the company to prepare a student for the feel of the airplane on their first flight, and a pilot who has never flown with a short-throw stick and

light controls could easily find themselves in a pilot-induced oscillation that damages the airplane. So there is risk in simply sending them out to go fly. Yes, there is also risk in the high-speed taxi scenario, so great care must be put into choosing the right weather and long, wide runways to allow some margin for error. The most important thing is for the pilot to be cautious and understand the risks they are taking in either scenario. Understanding the risks is the first step to finding ways to mitigate them—and as always, having the mindset to simply stop and think about what you are doing is the best way to keep all of the pieces of the airplane (and the pilot) together and unbent.

We suggest that the aspiring BD-17L pilot get some time in a sensi-tive airplane, possibly one with a side stick to make the leap from a Cessna to something with quicker responses to a given input. Many people report such a leap when transitioning into the RV line, and this would be a good place to start. What is ironic is that many pilots of RVs got their start in the Yankee, traceable in the lineage of the BD-17L as the original BD-1, and that is considered a good stepping stone for people making the leap into one of Van Grunsven’s designs. Sometimes, things just come full circle.

—P.D.

The stabilator, coupled to the side stick, accounts for the very light pitch forces—delightful to fly once the pilot is used to them.

tendency to try and spin when stalled power off—either straight ahead or in turns. The same held true with power-on stalls, but then again, there isn’t a lot of power available to do much of anything exciting in the stall. Break the stall with elevator and climb back out once the wing is flying, and you’re done.

With the feel of the airplane in hand, I turned to stability checks. Pitch stabil-ity—hands free—showed a very slow phugoid with little damping, but posi-tive. The diversions were very small, so I would expect the airplane to hunt in altitude a little bit, but not diverge. With the large vertical fin, the yaw stability was excellent as well, and roll held no surprises. It was time to get more aggres-sive, single-seat airplanes being the type to inspire fighter-pilot tendencies.

Of course, you can only get so aggres-sive with 65 hp. Like any low-powered LSA, the margin for maneuvering is not huge, so you don’t have the excess energy you’d have to wind it up in a steep turn or pull from level flight into a steep chan-delle or wingovers. But the airplane has good manners for what it can do, and I did steep turns of 60 degrees of bank for about 180 degrees before running out of energy. It is in the coordination maneu-vers like chandelles and lazy eights that the lack of harmony between pitch and roll were most noticeable, but one quickly adapts and compensates. These maneuvers demand constant coordina-tion, and after you do a few turns, you’ll have a good feel for how much control in each axis is required.

The EngineThe HKS engine is a two-cylinder, four-stroke, dry-sump engine with dual elec-tronic CDI for ignition. It performed wonderfully throughout the flight, although there was a slight tendency towards roughness at idle speed. Jim Bede Jr. attributed this to a slight prob-lem in synchronizing the twin carbs, but it was easy to simply let the airplane idle a little fast. Full power operations were just fine, and when I was out in the practice area, I let it wind up in level flight to see 120 mph on the airspeed indicator, with the tach showing 6200

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The BD-17L is an airplane that raises a significant point in how we evaluate airplanes and how pilots should think about them. The combination of a well balanced stabilator and small side-stick controller make for a very light and highly sensitive pitch control chan-nel in the little bird. It takes very small movements of the stick for just about any type of maneuver in the BD-17, and pilots take their arm off the rest at their own peril. I found that flying it with just my fingers was about right. Wrist motion was too much and could lead to over-rotation on takeoff or landing.

Yet the airplane is not unstable in pitch, and it is important for pilots to understand the difference. Sensitivity is the amount of response you get for a specific amount of input. Stability measures the airplane’s ability to return to the trimmed airspeed when disturbed—by a gust, for instance. We measure stability by trimming for a certain speed, then disturbing the airplane with a pull-up (or pushover), releasing the stick, and watching the resulting response. An unstable airplane will continue to diverge—pitch up, and it keeps pitching up—or it will return toward natural, overshoot, and get far-ther away from the trimmed condition, then go back, and the overshoots become larger. Airplanes like this are a handful to fly, and really not acceptable, except in very rare and specific flight situations.

A stable aircraft will return to the trimmed airspeed—at least at some point—usually after a few oscillations, or “phugoids.” If you make an airplane so stable that it returns immediately to the trimmed condition with no overshoot at all, it will seem quite heavy and unresponsive—great for a cross-country hauler, but not much fun as a sport plane.

Neutral stability is when the airplane keeps oscillating, but the phugoids don’t get any worse—it hunts around the trimmed speed forever. This can be annoying if you are trying to fly hands off, but can be desirable for a maneuverable airplane because the pilot doesn’t have to fight the forces trying to return it to the trimmed condition all the time.

You can have a sensitive airplane or an insensitive airplane, a stable or unstable airplane, or any combination of the two. The problem with a sensitive, unstable airplane is that it is extremely easy to overcontrol and cause pilot-induced oscillation (PIO). The same applies to one that is sensitive, but neutrally stable. The BD-17L is very sensitive and close to neutral in stability (although overall, it is stable), so the pilot needs to make sure not to overcon-trol. But if they can adapt, they’ll find it fun to fly and very responsive to small inputs. Just remember—the roll channel is much more heavy, so you need a different amount of input to get the same response in each channel—and this is where it pays to get good transition training so that you know what to expect.

—P.D.

Sensitive or Unstable?

rpm. Comparing this 65 hp engine to a Continental of the same horsepower installed in a J-3 Cub will show that the 17L is almost twice as fast. Then again, it’s probably less than half the size.

The airplane is currently sporting straight exhaust pipes with no muffler, and it is pretty loud to people on the ground. I could hear it departing for several miles when the test pilot left the airport to check it out. The origi-nal muffler for the HKS engine didn’t fit inside the cowl, along with the oil tank, so they are having a new, smaller muffled exhaust built that should quiet things down quite a bit. Cockpit noise levels were about as high as a typical aluminum homebuilt with no inte-rior—loud, but tolerable.

With the air work finished, it was time to head back to the airport to see how the little plane lands. Traffic was an issue, so I didn’t have a tight closed pattern to myself, and with the braking problems I was having, I didn’t want to tempt fate by doing too many turns around the patch anyway. Slotted behind two other airplanes flying large patterns, I had a long time to stabilize the approach, and

with flaps out, it was fairly easy to stay on speed and on glideslope. I noted no unfriendly tendencies in the flare, and even with the winds beginning to come up, the rollout was straight—undoubt-edly helped by the big fin.

The low wing in a single seater like this is always very close to the ground (since everything is small), so ground effect is a noticeable variable in any landing. Stay-ing on speed and not getting too fast will help a great deal in making good land-ings. With the sensitive side stick, the novice BD-17L pilot will want to make sure that they keep their arm firmly on the armrest and flare with just the fin-gertips and a little pressure, or balloon-ing will result. Getting a good checkout in another sensitive airplane before fly-ing the BD-17L would be a good idea to make the first landings suspense free.

Small, Light, and SimpleIn the end, the BD-17L is just the airplane its designer set out to create. It is sporty, easy to build, and simple to maintain. Designed around the HKS engine, the airplane preforms just fine, but potential owners should be aware that they need to

learn a lot about the powerplant them-selves, for at strange fields, you might get blank stares if you ask for help on any-thing but a Lyc or Conti.

Performance-wise, the BD-17L is great for cruising around the local area, and the factory says that one fellow they know used his as a commuter in the Florida area. Setting out on a multi-day cross-country will be an adventure—but people have done this with much slower airplanes since the days of the Wrights.

Bedecorp has been around since the 1960s, and yes, Jim Bede Sr. attracted controversy because of the failure of the BD-5 project that left many dream-ers out their deposit with nothing to show for it. But many of those dreamers picked themselves up and decided that, by gum, aviation was important to them, and they’d find something else to fly! In that way, Jim Sr. inspired a lot of today’s aviators—some might argue the hard way—and while they didn’t get their per-sonal spaceship, they found something else that worked for them just as well. The BD-17L is worth a look to see if it fits your size, style, and budget for a fun machine with which to take wing. J

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