Bede BD-5 Micro

Description

 

 

 

The Thrill of Flying the World’s Smallest Jet
Debbie Gary

Last summer while I watched Justin Lewis perform at an airshow in his polished silver BD-5J, that old feeling came back. I longed to strap into a BD-5 jet again. I wanted to dive it along the show line, pull up vertical, gyrate through a Wild Turkey, drift backward into a tail slide, bop the gear up and down, then zoom past the airshow crowd the way we used to in 1975, when I was the third pilot of the BD-5 Jet Team.

Sleek as a bullet, efficient as a sailplane, sexy as a little Reno racer, the BD-5 was the key piece in Jim Bede’s 1970s dream of affordable, fun flying for the masses. Bede had already hit a home run, selling more than 800 kits for his boxy, practical, build-it-yourself BD-4. But orders for the BD-5 soared into the thousands.

The airplane whispered fantasy and adventure. Nothing about it said wife and kids. Built at home, slipped on at the airport, it was a single-seat, man-size toy. With a fuselage not much bigger than a motorcycle (empty weight: about 450 pounds), it earned a Guinness record as the world’s smallest jet. Its wings and tail could be removed for storage in a garage instead of an expensive-to-rent hangar. The public panted for it. Even before the airplane flew or the engine ran, people sent deposits hoping for kits to build or places in line for the production model.

At the Experimental Aircraft Association’s AirVenture in Oshkosh, Wisconsin, last July, Lewis told me that seeing BD-5 jets in the 1980s and 1990s inspired him to fly. He also talked about building his own Flight Line model with Skeeter and Richard Karnes at BD-Micro Technologies in Siletz, Oregon, one of the places where amateur builders can get help putting a BD-5 together. Because the Federal Aviation Administration classifies the BD-5 as “experimental,” the Karneses, who bought parts from one of the original dealers, are able to make any modifications they like. Lewis described the changes. “It has beefed-up wings, a more powerful engine, and a five-inch stretch to the fuselage. It still flies like a dream,” he said with a grin. For my part, I told him stories from when I was left wingman on the demonstration team with fellow airshow pilots Bob Bishop and Corkey Fornof. Back then the jet was relatively new, full of surprises, and watched enviously by crowds of people who wanted one of their own.

Bede Aircraft had already begun its historic tail slide when I flew my first airshow with the team in May 1975, but I did not know that. Marketing was so far ahead of development that incomplete kits were being shipped to customers; necessary parts simply hadn’t been made. More ruinous, there was no off-the-shelf, airworthy, two-cycle piston engine for the -5, and it was the low-cost piston engine model that homebuilders wanted, not the $20,000 jet. No airplane had ever used such an engine, and in trying to develop one, Bede’s team of engineers and the snowmobile engine manufacturers they were working with seemed to be running in quicksand.

Still, everyone I worked with was under the airplane’s spell. Bede Aircraft in Newton, Kansas, was a magnet for pilots, mechanics, and engineers excited about homebuilding airplanes. Fornof, who led the jet team and had flown airshows in the P-51 Mustang and F8F Bearcat, acquired a Bede dealership to sell kits and later, he hoped, production airplanes. Bishop, who had become famous for his airshow performances in the Bellanca Super Viking, flew right wing and had put a deposit on one of the production models. Dan Cooney, destined to solve mysteries in the drive train that linked the mid-fuselage engine to the rear-facing propeller, showed up in Newton with his Cessna 172 ready to camp out until they found him a job. Engineer Al Thompson, who worked out how to build the unique mechanical landing gear, arrived from Boeing. Now-famous aircraft designer Burt Rutan left a civilian job at Edwards Air Force Base to become Bede’s flight test director.

“This was the only real job in the homebuilt industry,” says Rutan. “There wasn’t any place else where I could work a day job that was something I did for fun at night.” Rutan arrived in Newton with his own, nearly finished design, the VariViggen. While he was at Bede, from 1972 to 1974, he improved the BD-5 prop version, converted the propeller -5 to the jet -5, and developed Bede’s concept of a trainer called Truck-a-Plane: a BD-5 airframe suspended from a trapeze in front of a pickup truck. It offered a simple, ingenious way to practice the critical first and last 20 seconds of flight, close to the ground. Since the BD controls were extremely sensitive and the airplane sat as low to the ground as a glider, takeoff and landing were tricky for inexperienced pilots.

Rutan’s other contribution was to make Les Berven the BD-5’s test pilot. Rutan and Berven worked together at Edwards and flew the airplanes in the base’s aero club. “Even though Les was a flight test engineer like me, he was bonkers about flying,” Rutan says. “He was a stick-and-rudder guy. I knew Les would be a better pilot for a BD-5 than any military test pilot stepping down from Phantoms or F-15s.” Bishop called Berven our cowboy test pilot. He was serious about his test flying, but everything else was fodder for his wacky humor, like the rivet gun recording he hooked to his radio, which in our cockpits sounded like a machine gun shooting us down.

Even people in the office felt the little jet’s magic pull. Carol Hall worked with her husband John, who was marketing vice president. “It was almost a cult,” she says. “You belonged to something. You worked for a cause. If you didn’t get paid, well, you could live on creativity. John and I worked in the car driving to Newton from Wichita with boxes of folders and files, answering letters. We took the kids there in our Volkswagen camper on weekends. We were all working to provide this wonderful airplane to all these customers who put money down. Those $200 checks that came in just to hold a spot, they just poured in. You couldn’t count them fast enough.” John Hall was critical to Bede’s business in two ways: He directed the BD-5’s extensive publicity campaign, and he lovingly drew the BD-5 building plans, famous for their meticulously planned build sequence.

I showed up in Newton because Bishop and Fornof said there might be a job for a wingman if I had time to hang out. I had just finished a year and a half in Canada as a pilot on the four-Pitts Carling Aerobatic Team when Bishop called me to replace their number three pilot, Ed Mahler. The little jet is slippery and sensitive, and the six-foot-four Mahler found it awkward in formation. So he became their solo pilot until the day his jet sucked in contaminated fuel at Corpus Christi and flamed out, and the aircraft went down on a sandy patch near the airport. Mahler peeled off the fuselage and escaped with a broken palate. Fornof and Bishop flew the rest of their 1974 20-show season without him. (Mahler went back to flying his Parsons-Jocelyn biplane; in 1977, he crashed it in a show and died.) Bishop had seen a video of me flying in the Carling Team, so he figured I could do the job, and he thought a woman on the team would increase its market appeal for a corporate sponsorship. Fornof was skeptical; he didn’t know any professional women formation aerobatic pilots, because there were none—except me. I’d led a team for acclaimed airshow pilot Jim Holland from 1971 to 1973, then flew the number four, or slot, position on the Carling Aerobatic Team. (The slot flies right behind the leader in a diamond formation.) When I showed up in Kansas that May, Fornof said I could try out, but that I would probably not be ready to perform with the team before Oshkosh, at the end of July.

But when we flew together, I felt at home in the jet and comfortable with their formation routine, and Fornof changed his mind. In the journal I kept in 1975, I noted what he said: “If a man had flown that well, I wouldn’t have been quite so surprised.” We both laughed. It was the sort of thing people said in the 1970s, but I didn’t let it offend me, and I never let it stop me. Our new team flew our first show 10 days later there in Newton for Bede customers and employees, and the rest of the summer the three of us had a wonderful time flying together.

Our job on the jet team was to keep the BD-5 in front of the public. At the start, Bede invited us all to his office for a welcoming toast. I looked around. Bookshelves held thousands of National Advisory Committee for Aeronautics manufacturing reports dating from the 1920s and 1930s onward, some printed on cheap, fragile paper from World War II. “Have you read all these?” I asked.

“I live on them,” Bede said, reaching for the one titled The Hinge Moment of Control Surfaces. “Here is one of the secrets to the BD-5’s beautiful flying characteristics.”

Handmade models on a cabinet across from his big desk gleamed under a spotlight. With Bede’s drawing on quadrille paper as a guide, Paul Griffin designed them. In 1964, after reading a Mechanix Illustrated article about the BD-1, Griffin joined Bede Aviation (which became Bede Aircraft) as an illustrator. His models gave life to Bede’s ideas. At the flight test center, he would work a full day on the BD-5 project, then stay late sanding a model of the next Bede concept.

Because of the slow and partial shipments of kits, the initial intoxication over the propeller version of the BD-5 needed reinforcement. We all got a chance to fly the prop plane too. In fact, right after the Newton show, we took one to the big airshow in Reading, Pennsylvania, because our jets had been shipped to Edwards for testing and research by the Air Force. With Bishop’s supervision, the U.S. Navy had used the jet to mimic a cruise missile in an effort to convince the Carter administration that a cruise missile was a better cold war weapon than the B-1 bomber. Now it was the Air Force’s turn. It was fun to imagine this seemingly frivolous little machine having a secret life as a military weapon, or as a spy’s tool. Hollywood also saw its spyplane potential, casting it in the 1983 James Bond movie Octopussy, with Fornof at the controls as Roger Moore’s double.

At our next jet show, in Mojave, California, I made five practice flights, and each time I rolled or dived, my engine made harsh sucking noises and flamed out. No formation flying for me that weekend. Instead, the show was memorable for a different kind of experience. I allowed one curious fan to sit in my jet, and as I was telling him that its range was 550 nautical miles, another man interrupted. “You can cut that by 90 percent. You can cut anything Jim Bede says by 90 percent,” he said. “Jim Bede is all talk, and anybody who works for Jim Bede is a liar!”

Although I’m embarrassed to admit it today, I thought he was a crank slandering a guy I believed in, and I told him to get lost. Recently I asked Bede about that tough time for him and the company. “Out of about 10,000 customers I got some very mean hate mail from about 100 people,” he says. “Some people thought that if they really put pressure on me and made me feel bad by writing to the magazines and the government that I would solve the problem.”

But making Bede feel worse didn’t solve the engine problem. “When you are running as fast as you can and somebody says ‘There’s a flaming torch behind you, run faster!’ you go ‘This is as fast as I can go here,’ ” he says today. “So many good people like Paul Griffin and John Hall put all their effort into it.”

And enthusiasm for the BD-5 was so broad, way beyond the homebuilt market, that Bede believed the way forward was to manufacture a production airplane. This required getting the airplane certified by the FAA, a tedious process involving unimaginably vast amounts of time, money, and red tape. In 1972, right after Curtis Pitts got his aerobatic Pitts biplane certified, he told me, “If I had ever known how difficult and expensive it was going to be, I never would have done it. It cost more than a million dollars.”

Bede sank his house, his personal accounts, everything he and his family owned into the company to try to save it, and somehow remained optimistic about future deliveries.

Our jets spent a lot of time at Edwards in the summer of ’75, and the next time we climbed into them was to taxi out for the Fourth of July show in Lancaster, Texas, near Dallas. I had gone six weeks with no three-ship practice. Formation aerobatics is all about timing and practice. On the Carling Team, we had a big budget and plenty of control, so our training included six weeks of winter practice. The Bede Jet Team was on a very tight budget, but after the Lancaster experience, we never did another show without practice.

The Fourth of July weekend in Texas was so hot that 40 people in the crowd fainted, and the air was as rough as stones. We dived in for our first loop and I cranked my elevator trim to the full nose-down position to make my controls so heavy that I would not chase the bumps and have the jet’s nose bounce up and down like a truck with bad springs. Don’t move the stick, I told myself as the plane rode over the bumps. In an aircraft as light on the controls as the BD-5, it is easy to overreact. It was hard work, but that’s the fun of formation flying.

Another part of the fun of being on the team was traveling to shows in Bede’s DC-3, which also transported our jets. For four years I had traveled to shows in a Pitts with all my belongings stuffed in a tiny back hatch the size of bread box, so I was giddy over all the space and freedom the DC-3 gave us. We three took turns: up front as the copilot, or in the back on a bench. It was a party back there, with buckets of fried chicken and magazines we read aloud to each other. The jet fuselages were turn-buckled to the floor with the wings and horizontal stabilizers tied down under them, wrapped in blue sleeping bags. It was especially fun arriving together for my first airshow at the yearly Oshkosh convention.

We performed both solo and team flights, and when not flying, we manned the Bede booth. By the second day I was hoarse from raving about the BD-5 and shouting hello to what seemed like everyone I had ever met in aviation. Although we performed our formation flight in the rain, we flew the routine with rhythm and finesse, and I remember feeling great; but I also remember that I got a slow start on takeoff. From the left wing I saw Corkey’s mouth move, then his jet crept away before I realized I was on the wrong radio frequency.

What I was really looking forward to was my solo flight; I had practiced a surprise. Our jets had been home with us for a week, so I’d had a chance to experiment. The Bede jet could do things that other jets can’t: snap rolls, tail slides, and our signature level pass, called Now You See Them, Now You Don’t, with the landing gear popping in and out as we moved the mechanical landing gear lever forward and back. My surprise was to do an inside/outside figure eight, the first and maybe only negative 3-G maneuver done in a Bede jet at an airshow. Before I tried it back in Newton, I checked with Berven and the company mechanics and engineers. I stayed within the airplane’s G and oil pressure limits, so I expected no problems. The airplane sailed through the inverted portion of the eight as if it was built for negative Gs. It delighted me, but not Bishop. “The nickel cadmium batteries are right under your legs,” he said after I flew. “The caps on those batteries are only certified for three negative Gs. If that stuff got loose on you, you would have been in very bad shape. You could have lost the use of your legs.” I didn’t perform another inside/outside figure eight.

Bishop was not just a talented wingman, but also the one who gave us reality checks. He knew the airplane better than anybody else. Not long after Oshkosh, something happened that made him say our days as a show team were numbered. For a long time, the engineers and mechanics had been working to perfect the “conformity model” BD-5 so the airplane could meet FAA certification requirements. We all thought the BD-5 production airplane was just around the corner. That’s what we told people we met on the show circuit, and deposits rolled in from customers wanting places held in line for them. But Bishop sensed that the delays were not the ordinary hurdles that every airplane has to overcome during development, so he introduced Bede to Rod Absher, the aircraft production expert who saved Bellanca Aircraft 800 man-hours per airplane when the company set up its new production line. After a couple months at Bede’s, Absher took Bishop aside and said the company was a long way from starting production.

In September, I left Bede’s to fly solo shows in my new Pitts S-2A and to set up an aerobatic school at Art Scholl Aviation in California. Bishop and Fornof left a couple months later to build their own jets and find other sponsors. They flew together for a long time—first as the Acrojets, then as the sponsored Sonic Jets. Then they split; Fornof headed for his movie stunt flying career, and Bishop formed the long-running Coors Silver Bullet Team. Bishop did some BD-5 test flying for Ames Industrial Corporation, which had built the original BD-5 jet engine under license from the French engine builder Microturbo (then Sermel). The company had purchased 20 BD-5 kits, and Bishop negotiated a good deal for 19 sets of parts. He has since used the kits to build many of the jets he now owns and flies under contract for the military as the Small Manned Aerial Radar Target, or SMART-1. Justin Lewis, an Air National Guard pilot as well as an airshow performer in the BD-5FLS, sometimes flies missions for Bishop.

In 1979, Jim Bede lost his company, his savings, and his home to bankruptcy. Customers lost their money too. Bede didn’t intend to cause harm; he just didn’t see how bad things had become.

Bede has written a book about his experience: The BD-5 Story. It’s sold by the company he formed with his two sons in 1998, Bedecorp, which also sells kits for four models, including the BD-4. But not the BD-5. Bede calls the BD-5 a dream. It was a dream I got to live in the summer of 1975.

The Bede BD-5 Micro is a series of small, single-seat homebuilt aircraft created in the late 1960s by US aircraft designer Jim Bede and introduced to the market primarily in kit form by the now-defunct Bede Aircraft Corporation in the early 1970s.

The BD-5 has a small, streamlined fuselage holding its semi-reclined pilot under a large canopy, with the engine installed in a compartment in the middle of the fuselage, and a propeller-driving engine – or jet engine in the BD-5J variant – mounted immediately to the rear of the cockpit. The combination of fighter-like looks and relatively low cost led to the BD-5 selling over 5,000 kits or plans, with approximately 12,000 orders being taken for a proposed factory-built, FAA-certified version. However, few of the kit versions were actually completed due to the company’s bankruptcy in the mid-1970s, and none of the factory built “D” models were produced, as a result of the failure to find a reliable engine for the design.

In total, only a few hundred BD-5 kits were completed, although many of these are still airworthy today. The BD-5J version holds the record for the world’s lightest single-engine jet aircraft, weighing only 358.8 lb (162.7 kg)

The Micro concept
Development of the “Micro” dates back as early as 1967, when Jim Bede was inspired by the Schleicher ASW 15. Along with his chief designer, Paul Griffin, they make preliminary designs of what would become the BD-5. At the time, however, Bede was working on the Bede BD-4.

Serious work on the Micro started in 1970, with construction of the prototype starting in earnest late that year. While the BD-4 was fairly conventional looking, the Micro was a radical design. It is an extremely small one-seat design that looked more like a jet fighter than a typical general aviation aircraft, with the pilot sitting in a semi-reclined position under a large fighter-like plexiglas canopy only inches above the pilot’s head. Behind the cockpit was a compartment housing a two-cylinder air-cooled 40 hp (30 kW; 41 PS) piston engine[a] driving a pusher propeller.

For improved performance the aircraft featured both a V-tail and retractable landing gear in order to reduce drag. Calculated drag was so low that split flaps and spoilers were added to the wing in order to improve deceleration for landing. This was apparently the first application of spoilers on a light aircraft. The low drag implied excellent performance; with the 40 hp engine it was expected to reach “nearly” 200 miles per hour (320 km/h), while the larger 55 hp (41 kW; 56 PS) engine allowed it to cruise at 200 mph with the 21 ft 6 in (6.55 m) “B” wing, and have 1,215 miles range. With the shorter “A” wing, 14 ft 3 in (4.34 m), it would be fully aerobatic and have a slightly higher top speed. Builders could optionally buy both wings, switching them in about 10 minutes.

In addition to being easy to fly, the BD-5 was also intended to be easy to build and own. The fuselage was constructed primarily from fiberglass panels over an aluminum frame, reducing construction time to only a few hundred hours. Although the early designs required some welding in the landing gear area, it was planned that this would be removed in the kit versions, so construction would require no special tooling or skills. Even the cost of operation would be extremely low, offering fuel efficiency of 38 mpg‑US (16 km/L) With the wings removed, the aircraft could be packed into a small custom trailer, allowing it to be towed away by car for storage in a garage, and from there to any suitable flat area for takeoff.

Bede published an information booklet about the BD-5 in November 1970. Several very positive magazine articles appeared at this point. The October 1971 issue of Science & Mechanics had the BD-5 on the cover, listing the price as $1,950. The associated article showed the construction of the original prototype, with numerous claims about how easy it was to construct. The August 1973 issue of Popular Science also covered the aircraft, although it listed the price at $2,965 with the 40 hp engine. The “miniature fighter” generated intense demand. As one author put it, “Even before the plane first left the ground, thoughts of flying the sleek, bullet-shaped aircraft with its pusher prop stimulated the imagination of nearly everyone who had heard of the program.”

On February 24, 1971, the first $200 deposit to reserve a “place in line” to receive a kit was accepted, with the target shipping date being May 24, 1972. By August 1971, 800 deposits had been taken, even though the first BD-5 prototype had yet to complete high-speed taxi tests. By the end of the year, the company had taken over 4,300 orders, making it one of the most popular general aircraft projects in modern history.

Flight testing
N500BD
The prototype, N500BD, flew briefly on September 12, 1971, powered by a 36 hp (27 kW; 36 PS) Polaris Industries snowmobile engine. This was sixteen months after deposits had been taken, which led to some griping in the press.

The stability of the aircraft with the original V-tail was marginal at best and clearly needed a redesign. With the original fibreglass fuselage, this was a time-consuming process, so the decision was made to switch to an all-metal fuselage with the components incorporating compound curves produced using hydroformed aircraft-grade aluminum alloy. These could be modified with relative ease during the testing cycle. It also made economic sense as the orders rolled in, the $30,000 in tooling would be spread over what was now a large order book.

By December 1971, the tooling for the new fuselage was in development. The aircraft now featured a longer, more pointed nose, whereas the N500BD had been patterned on the ASW 15 and had a more rounded, egg-like shaping at the front. While this work was in progress, Bede continued to experiment with modifications to the empennage, eventually abandoning the V-tail for a more conventional rudder and horizontal stabilizer layout with highly swept surfaces. Further testing on N500BD showed flow interference between the horizontal surfaces and the propeller, and the stabilizer was raised six inches to correct it, placing it about midway up the rear fuselage.

N501BD
The first example of the new fuselage arrived in March 1972, and was fitted with a new Kiekhaefer Aeromarine engine Bede had seen at the Oshkosh Airshow in 1971. Finished as N501BD, numerous small delays prevented it from flying until July 11, 1972. These flights demonstrated continued problems with the pitch stability; after briefly considering an all-flying stabilator, it was again redesigned with more area and less sweep, becoming much more conventional in layout.

The program was now far too large for Bede to handle alone. In March 1972, he hired Burt Rutan to head the flight test department, who was soon joined by Les Berven as chief test pilot. They took over development, giving Bede more time to work on business issues. This was proving difficult enough, as Kiekhaefer and Bede could not reach an agreement about deliveries, forcing him to change to a similar 40 hp 440 cc (27 cu in) Hirth Motoren design, then selecting a larger 55 hp 650 cc (40 cu in) Hirth, instead.

Several additional problems turned up during testing. Stick forces were very low, but this was easily addressed by making the servo tabs 50% larger. A more worrying development was that the engines all had problems with mixture due to changes in engine speed or load, which led to rough engine operation. In August, while Bede was demonstrating the BD-5 (N501BD) to the FAA in order to receive permission to fly at Oshkosh, the engine seized. On its deadstick landing, the aircraft overran the runway, buckling the nose gear. Incorrect mixture was identified as the cause of a second wreck of N501BD, in September 1972, when the mixture control broke and Berven had to execute another forced landing. This landing resulted in damage to all the gear and the fuselage as well.

Since N502BD would be ready in two months, they decided not to repair N501BD, and it ended testing after about 30 hours of flight time.

N502BD
N502BD ran into problems of its own. Early models used a variable speed belt drive system to transfer power from the engine to the propeller shaft. This was removed from N502BD and it suddenly began exhibiting a serious vibration problem during taxi tests. Experts were called in, and a freewheel clutch and additional bearings added to correct the problem, but it was not until March 26, 1973 that N502BD flew. From then on the test program seemed to go more smoothly, although this aircraft also suffered two dead stick landings, one from a pinched fuel line occurred while the plane was being observed by the Popular Science author, and another due to metal in a new engine’s cylinder.

By the time the test program neared its conclusion, the aircraft had undergone major changes. One victim of the program was the shorter “A” wing, which calculations showed would only improve performance at speeds very close to Vmax (the highest available speed). Flight testing also showed the stall speed with the smaller wing was decidedly high. Split flaps and spoilers had also disappeared. The canopy and cockpit dimensions had changed, the aircraft had new landing gear systems, and the tail was completely new. Estimated top speed was also reduced 10%.

The biggest change, however, was the engine. The original plans to use a 40 hp model proved to be decidedly underpowered, although they were still offered for a time. It was the need for more power that would fit into the very small engine bay that demanded the use of a high-revving two-stroke engine, and few examples of such a design in the desired power class were available. Additionally, two-stroke engines are very smooth running at high RPM, but have real problems running smoothly at low RPM. Even after months of effort, the Hirth designs showed rough running and high minimum power outputs when idled. Two-strokes also have high fuel consumption, and it was expected that the larger engines would burn between 4.5 and 5.5 gallons per hour.

By this point, it seemed the basic design was complete, and Bede turned his attention to other projects. One was the jet-powered BD-5J, which boosted performance to 305 knots (565 km/h; 351 mph). There was an attempt to sidestep the engine problem with the BD-5S glider (S for Sailplane), with lengthened wings and no engine, which prompted Air Progress magazine to sarcastically note, “At last, a BD-5 with no engine problems.” This glider version did not fly well and the project was scrapped. Some work on a BD-6 was also carried out, essentially a shrunk BD-4 single-seater. There was some criticism that Bede should have attended to the basic BD-5 rather than move on to these other projects. Bede also decided to seek FAA certification of the BD-5D as a production aircraft and sell it complete, and began taking $600 deposits for this model.

Deliveries begin
By the middle of 1973 the basic design was complete and the tooling set up for production. Now over two and a half years after the deposits started being taken, the engines were the only part holding up deliveries, so Bede offered to ship the kit with the engine to follow. This was a fairly attractive option; it meant the builder could get to work and hopefully complete the airframe by the time the engine arrived, at that point expected in September 1973. Many builders took the company up on the offer, only to receive incomplete kits and plans.

Initially, all three Hirth engines were offered; builders could keep the 40 hp engine, or “trade up” to 55 hp or 70 hp (52 kW; 71 PS). The latter, which Bede had developed with Hirth, was now considered the baseline engine for the aircraft; when equipped with the original 40 hp the aircraft proved to be underpowered. In a late 1973 newsletter to prospective owners, Bede suggested the 70 hp model and discouraged use of the smaller engines. Prices had risen throughout the 30 months since deposits were first taken. Originally priced at $1,799, the base price was raised to $2,599 with the 55 hp Hirth, and owners were offered a “trade up” for the difference in price if they had ordered the aircraft with the original 40 hp engine.

When 1974 came, engines were still not being delivered in sufficient numbers, although some started to arrive early that year. At that point, unexpectedly, Hirth went bankrupt after about 500 engines had shipped. Once again, the BD-5 lacked a suitable engine, but this time the search for a replacement ended with a Zenoah design from Japan. Development of this engine was lengthy, and in the end it would not be certified for export until 1978, although this was not anticipated at the time.

In the meantime, Bede came up with another novel solution to the problems of converting pilots to the new aircraft. They took an engine-less example and bolted it to the front of a pickup truck on a trapeze, attaching the pilot’s throttle control to the truck’s. Pilots could test fly the aircraft without danger – if a problem developed the driver of the truck simply hit the brakes.

Deliveries end, Bede bankruptcy
After more than 5,100 kits had been delivered to prospective builders, the kits stopped shipping as well. Although the company was effectively bankrupt at this point, work on the BD-5D continued for some time. The bankruptcy became official in 1979, by which point the BD-5 project was long dead. During the bankruptcy proceedings, it was learned that the money ostensibly being used to build kits was instead being spent on a variety of other projects. As a result, Bede entered a consent decree with the FTC to no longer accept deposits on aircraft for a period of 10 years.

BD-5B powered by a Subaru EA-81 engine
Many owners stored, abandoned, or sold their incomplete kits, but a few hundred diehard builders finished them with a variety of engines, with installations designed by third parties and former Bede Aircraft dealers. Having to hunt for an engine was only one problem. The time to build the aircraft was much longer than quoted; original estimates from the company put it at 600 to 800 hours but users estimated it to be as much as 3,500 hours. Some of this was due to the need to fit their selected engine into an airframe designed for the Hirth, which was no longer available. Additionally, the construction techniques had improved somewhat since early Bede designs, but fastening the panels still required drilling, deburring, dimpling, drilling again and deburring again for each rivet. With the original mixed-construction design this would not have been as much of a task, but with the all-metal version this was extremely time-consuming. While Bede claimed the aircraft could be put together by anyone in a garage, builders generally agree that doing so without proper construction techniques could result in a potentially dangerous aircraft. One way to overcome that issue is to use a set of properly laid-out jigs to align and drill the pilot holes for the airframe, wings and other components. For all of these reasons, it was some time before completed BD-5s started to appear.

Additionally, some of the kits were shipped with missing parts, adding to the confusion. All of this led to a rash of kits being sold for fire sale prices, although this did allow the builders to complete kits at bargain prices.
Flying starts
Although Bede had suggested using the B wings, the earliest kits shipped only with the short “A” wings. All four examples completed with these wings crashed on their first flight, three on takeoff, one on landing. In three of the four crashes, the pilots were killed. Of the first 25 aircraft completed, with both the “A” and “B” wings, 14 crashed with 9 fatalities.

Even when examples with the “B” wings were completed, the safety record did not improve greatly. Several crashes in the BD-5B were found to have taken place due to engine failure on takeoff, both due to the mix of “oddball” engines as well as endemic cooling problems. The reason this is such an issue with the BD-5 is twofold – the high line of thrust means an engine failure immediately results in an unexpected (for most pilots) nose-up attitude change. Pilots who fail to fly the aircraft first and then attempt to restart the engine inevitably stall, with the associated consequences. This was aggravated by the fact the original wing had a very sharp stall with little warning and a nasty tendency to snap roll. To make matters worse, a documented manufacturing error in some wing skins delivered to kit builders exacerbated the problem. A rather small center of gravity range added to the problems of properly trimming the aircraft.

Further developments
With the demise of the Bede Aircraft Company, the BD-5 entered a sort of limbo while builders completed their kits. The early safety problems and the challenge of adapting a suitable engine exacerbated delays. Over the next few years, however, solutions to most of these problems arrived in one form or another. Many other changes have also been incorporated to improve the original design.

The problem of finding a suitable engine with 60–70 hp (45–52 kW; 61–71 PS) yet weighing under 100 lb (45 kg) was a serious problem in the 1970s, but today there are a number of off-the-shelf designs in this class. The widely available Rotax 582 is a 65 hp (48 kW; 66 PS) engine weighing 80 lb (36 kg) in standard configuration, almost tailor-made for the BD-5. Other engines successfully used in BD-5s include the Subaru EA-81, Honda EB1 & EB2 (with and without turbocharging), Hirth 2706, AMW 225-3 and 2SI 808. A BD-5A fitted with a Rotax 618UL 74 hp (55 kW; 75 PS) two-stroke two-cylinder, water-cooled engine holds the current FAI C-1a/0 class speed record (aircraft weighing under 660 lb (300 kg)) at 351 km/h (190 kn; 218 mph).

Problems with the abrupt stall were mostly addressed by Harry Riblett, an airfoil designer who documented a procedure to apply a slight reprofile of the wing root airfoil, which softened the stall response of the aircraft without any significant performance degradation. The reprofile presents other unique problems, associated with the way it is applied to the wing upper surface, essentially glueing foam to the aluminum skin and covering with fiberglass. Similarly, the small center-of-gravity range has since been addressed with 5.5–13 in (14–33 cm) stretch kits for the fuselage.

Several companies were formed to help builders complete their kits, and many of the aftermarket modifications were worked into these services. As of 2015, BD-Micro Technologies of Siletz, Oregon continues to offer kit building support, including new-build kits featuring (optionally) all of these modifications and powered by a 64 hp (48 kW) Rotax 582 or 65 hp (48 kW) Hirth 2706 two-stroke engine, and even the BD-5T, a turboprop version using a TRS-18 turbine powering a mechanically-controlled variable-pitch propeller. Alturair, Inc. of San Diego, California also offers extensive parts and construction assistance services, as well as kits for the BD-5B and BD-5G models.

Bede Aircraft Company has since re-formed and has been working on several new designs. Before his death in 2015, Bede hinted at a two-seat tandem version of the aircraft, called the “Super BD-5”, using a certified aircraft engine and a number of modifications and improvements, but nothing more than a preliminary design drawing was made available.

Variants
BD-5
Prototype and initial kit production aircraft with short wingspan.
BD-5A
Short wingspan version, with 14 ft 3 in (4.34 m) wings tuned for high speeds and aerobatics.
BD-5B
Main piston engined production kits with wings extended to 21 ft 6 in (6.55 m). Kits still available in 2011.
BD-5D
Factory built versions of the BD-5B.
BD-5G
Piston-engined production kit with wingspan of 17 ft (5.2 m) and a gross weight of 660 lb (299 kg). Kits still available in 2011.
BD-5J

“Bud Light Jet” BD-5J at Fargo 1997
While the new Hirth engine was being tested, Bede decided to create a variant of the BD-5 with a small jet engine. The result was the sleek BD-5J (also known as the “Acrostar Jet “[31]), a 300 mph (260 kn; 480 km/h) aircraft. The design used the Sermel TRS-18-046 turbojet which produced 225 lbf (1.00 kN) thrust and was used on a Caproni certified motorglider design. The original engines were produced under license by Ames Industrial in the USA. The wing was modified to an “intermediate” size between the original A and B wings, with a 17 ft (5.2 m) span.

BD-5J from “Octopussy”
Bob Bishop purchased 20 BD-5J kits as soon as they had appeared, and many of the flying examples started life in this batch of 20. Versions from the original batch became a popular airshow fixture. Throughout the 1980s and until 1991, Coors flew two of them as the “Silver Bullets”. Budweiser also had a BD-5J called the Bud Light Jet, but that contract has long expired and the aircraft was lost as a result of an engine compartment fire from which Bishop successfully bailed out. The aircraft also appeared in the opening sequence of the James Bond film Octopussy. Many of these aircraft have since been involved in crashes. The loss of the Bud Light Jet was caused by an incorrectly specified fuel flow sending unit which burst in mid-flight and caused fuel to be sprayed directly into the engine compartment. The fuel ignited when it came in contact with the hot components of the engine, forcing the pilot to trade speed for altitude, climb, and bail out. The aircraft then went into a flat spin and pancaked into the ground, but was sufficiently intact to allow the cause of the fire to be determined relatively quickly. On June 16, 2006, while practicing for an air show at Carp Airport in Ottawa, Ontario, Canada, Scott Manning fatally crashed in his “Stinger Jet,” one of the last BD-5Js to remain on the airshow circuit. The Transportation Safety Board of Canada report assigned probable cause of the wreck to the incorrect installation of the right wing, which caused the flap on that wing to suddenly retract in flight and create a “split flap” condition. The aircraft rolled to the right and Manning was unable to recover in time.Recently, the BD-5J has operated in the national security arena. The aircraft is certified by the United States Department of Defense as a cruise missile surrogate, with Bishop’s Aerial Productions offering a version known as the Smart-1 (Small Manned Aerial Radar Target, Model 1). The radar return and general performance characteristics make it a useful aid in training. On June 27, 2006, while flying one of these aircraft, pilot Chuck Lischer, a highly experienced professional air show pilot, was killed when he crashed into trees on final approach to the Ocean City Municipal Airport in Ocean City, Maryland. The National Transportation Safety Board investigation determined the aircraft returned to land with more fuel than recommended for normal operations and the pilot failed to maintain speed, resulting in a stall and subsequent impact short of the runway. The BD-5J has also held the Guinness record for the World’s Smallest Jet for more than 25 years. Bishop originally garnered the record with one of his jets, and in November 2004, the record changed hands to Juan Jiménez, whose BD-5J weighed in at 358.8 lb (162.7 kg) empty, 80 lb (36 kg) lighter than Bishop’s and the lightest documented weight for a BD-5. On May 1, 2013, Guido Gehrmann was killed while attempting an emergency landing in his BD-5J which he flew as part of Red Bull’s Flying Bulls team.
BD-5S
Sailplane version with extended wingspan. Flight testing was disappointing and further work was abandoned.
BD-5T
A turboprop conversion by BD Micro Technologies, powered by a Solar T62 gas turbine engine.

Acapella 100/200
An unusual adaptation of the BD-5, the Acapella 100 appeared in the early 1980s. Designer Carl D. Barlow of Option Air Reno mated a BD-5 fuselage with a distinctive twin-boom empennage and fitted it with a 100 hp (75 kW; 100 PS) Continental O-200 engine. Later, a 200 hp (150 kW; 200 PS)Lycoming IO-360 was fitted, and the span reduced from 26 ft 6 in (8.08 m) to 19 ft 6 in (5.94 m), becoming the Acapella 200-S. The prototype of this aircraft was first flown on June 6, 1980, with pilot Bill Skiliar at the controls. Nonetheless, it flew poorly and was difficult to control. Only one prototype was built and it was donated to the Experimental Aircraft Association’s Airventure Museum in Oshkosh, Wisconsin, USA, where it is occasionally placed on display.
FLS Microjet
Model produced in kit form by BD-Micro Technologies powered by a PBS TJ-100 engine. The 500 hour kit was sold for US$189,500 in 2011.

Aircraft on display:
BD-5B at Florida Air Museum in 2009
As of 2002, there were an estimated 150 BD-5s in airworthy condition.
BD-5 on static display at the EAA Aviation Museum in Oshkosh, Wisconsin. It is the prototype BD-5, N500BD, that started as with V-tail and fiberglass fuselage.
BD-5B on static display at the Steven F. Udvar-Hazy Center of the National Air and Space Museum in Chantilly, Virginia.
BD-5J on static display at the Pima Air and Space Museum in Tucson, Arizona.
BD-5J on static display at the Ernie Hall Aviation Museum in Warren, Ohio. It is on loan from the Ohio History Connection.
BD-5T on static display at the Hiller Air Museum in San Carlos, California.
BD-5J on static display at the Spirit of Flight Center museum in Erie, Colorado.

Specifications
Bede BD-5B, 70 hp

General characteristics:
Crew: One
Length: 13 ft 7 in (4.13 m)
Wingspan: 21 ft 6 in (6.55 m)
Height: 4 ft 2 in (1.28 m)
Wing area: 47.4 sq ft (4.40 m2)
Aspect ratio: 9.8
Empty weight: 355 lb (161 kg)
Max takeoff weight: 659 lb (299 kg
Powerplant: 1 × Hirth two-cylinder two-stroke, 70 hp (52 kW)
Propellers: 2-bladed, 3 ft 8 in (1.12 m) diameter fixed pitch, wooden

Performance:
Maximum speed: 232 mph (373 km/h, 201 kn) at sea level
Cruise speed: 229 mph (369 km/h, 199 kn) at 2,285 m (7,497 ft)
Stall speed: 55 mph (89 km/h, 48 kn) flaps down
Range: 935 mi (1,504 km, 812 nmi) optimum, with 30 min reserve
Rate of climb: 1,919 ft/min (9.75 m/s) at sea level
Take-off distance to 50 ft (15 m): 226 m (741 ft)
Landing distance from 50 ft (15 m): 253 m (830 ft)