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Famed Aircraft Designer James Bede Dies
linuxwrangler writes with a bit of news overlooked from last week, but worth noting: Prolific aircraft designer James "Jim" Bede has died at age 82. Although Bede designed numerous aircraft he is most commonly associated with the BD-5J, the "world's smallest jet", that was famously used to help James Bond escape in the movie "Octopussy." Bede's company currently has that aircraft for sale.
I've always been fascinated with Jim Bede's designs and his "get shit done" attitude. Personally, my favorite was the BD-10, a supersonic jet for folks on a high end cessna budget.
https://en.wikipedia.org/wiki/...
However, he is also somewhat infamous in the industry for how many of his creations have crashed and resulted int he deaths of their owners. Spark of brilliance with a bit too little attention being paid to safety and reliability.
Aerodynamically and structurally the BD-5 is fine (Burt Rutan was involved) but there are four issues that affect the stats for this plane (disclosure: I own one) but are not generally pointed out in these conversations:
1. The engine was never really solved. Jim started selling the kits with a scheme where people bought them in portions; a builder would buy as much as he could afford, build that much, then go back to buy the next portion, and so-on. By the time they got them fully built except for the engine, Jim did not have an ideal production solution (not an uncommon situation with a certain subset of "visionary" entrepreneurs). A bunch of builders adopted engines from small cars, snow mobiles and such things to their planes out of desperation to get their expensive toys finished and flying. These "solutions" were each custom, unique, and outside of the experience and influence of the airframe's designers. The BD-5 is not particularly spacious in the engine compartment, so these were always sub-optimal solutions.
2. These were home-built kit planes. While some such planes (like Rutan's canard-based designs) are very forgiving and aimed at first-time builders, the BD-5 is a bit of a sports car (both less-forgiving and attracting the sort of builder/flier who is more of a risk-taker and speed junkie).
3. There was a design change in the wing partway through the process that I think was not implemented by all kit-builders. Can't recall at the moment if it was an airfoil change or a wing washout (a slight twist from root to tip for you non-aero types) change, but it affected the flight envelope. Any BD-5 that did not implement the change would have different flight characteristics and almost certainly a different subset of stats.
4. There is a bit of a Corvair syndrome here: The Corvair, particularly the later sleeker-looking models, was a neat little car with rear engine that performed quite nicely and was quieter and cooler in the cabin thanks to that rear-engine. The very things that made the Corvair nice also meant that it handled differently because it was not nose-heavy like most cars. You do not want to put an inexperienced driver in a Corvair on ice. A very famous lawyer made quite a reputation for himself trashing the Corvair in the eyes of the general public even though the vast majority of those cars were driven safely for the full life of the product. The simple fact is that if you design a product that behaves differently from what the average Joe expects, the average Joe who is not paying sufficient attention will be more likely to get into trouble. The result is that the general public has a very-different impression from that of the owners with firsthand experience. The question for our society is this: Do we homogenize everything to the lowest-common-denominator and make everything bland and safe for the idiots, or do we still say that individuals are both free, and responsible, to make their own decisions and risk assessments?
Incidentally, this is all hardly unique. Rockwell used to make a beautiful high-wing twin called a Shrike Aero Commander. They had Bob Hoover fly around the country doing some of the most-amazing dead-stick aerobatics ever in the thing. The Shrike also had a less-than-stellar safety record (wing spar cracks issue). Properly maintained, inspected, and flown, the Shrike was a really neat plane. In the hands of a lesser-owner it could be a death trap. Welcome to the world of human-designed, human-built, and human-operated systems.
The BD-5 will always be there, even when the last one is scrapped or hung-up in a museum, as inspiration to the young future aerospace engineer. RIP Jim Bede. Not a perfect airplane guy, but always pushing to make things better for aviators while others went with the mainstream flow.
Uhmmmm.....No. The plane was not designed correctly. In one failure that killed the owner/business CEO that had bought the rights to the BD-10 design, the NTSB "concluded that Bede's" stronger vertical tail "fix was severely under-designed, and offered nowhere near the strength that had been calculated. Fox (company that had bought the BD-10 design) had not performed any testing to verify the redesign of the vertical stabilizer spars before continuing flight testing, instead relying upon the data provided by Bede." The new owner obviously should have tested the tail fix, but the fact remains that Bede didn't do the calculations correctly.
In addition, the owner of the last flyable BD-10 jet kit had the plane literally disintegrate on him.
Read all about it here: https://en.wikipedia.org/wiki/Bede_BD-10
Gordon
The BD-5 is a propeller-driven plane with an internal combustion engine, which Bede derived from a sailplane version he never sold. The Sailplane version was originally going to be all fiberglass and had higher aspect ratio wings. The BD-5 had the same basic shape, but with shorter wings and was built from aluminum.
The BD-5J is a jet-powered version of the BD-5, and due to the costs, pilot ratings, and limited availability of small jet engines, very few of the J version were built (most kit builders built the propeller version). The BD-5J is the same basic airframe as the BD-5, but with a small jet engine that exhausts through the spot where the (pusher) propeller shaft emerges in the BD-5. Note of interest: The US Military has occasionally contracted with owners of BD-5J's to fly them during exercises simulating inbound cruise missiles [grin]
Incidentally, to clarify for those James Bond fans: the BD-5 (and 5J) are indeed very small and fit in a small trailer or garage but they do NOT have folding wings as the movie prop did. On the real airframe, the wings are removable for transport/storage.
Pilots moving to the BD-5 were NOT transitioning from a Cessna or Piper to a transonic jet. Nobody I know of flew the jet version without firs flying the prop version. Also, given the small single-seated nature of the thing, Bede was quite aware of the pilot training issues in the pre-simulator (for private pilots) era, so he and his team had a trailer with a BD-5 on an articulated arm that could be towed behind a truck at speed up and down a runway. People who chose to train that way could experience take-offs and landings and get a feel for the ground effects handling in relative safety (the BD-5 wing is so close to the ground that the ground effects are significant).