It is with the greatest of
pleasure that I welcome this opportunity to talk to you about the BKB,
my father’s controversial sailplane, the real story of which has been clouded
for so long. If you have heard of the BKB, it’s likely to have been
in connection with words like tumbling, aerobatics, and unpredictability.
Some of you, especially if you are young or new to the sport of gliding,
may not have heard of it at all. There is much to tell about the
BKB, but I suspect I’ll raise more questions than I‘ll answer.
I have a mission here
today and that is primarily to correct some serious and prevalent misconceptions
about who designed and built the BKB. But my mission has a second
and very important part also, and that is to obtain more information about
this very unique aircraft; how it performed in its later years, what caused
it to crash, and could it really tumble? I’d like also to revive
some interest in the BKB, especially academic and analytical.
But first it’s important
to tell you that this little sailplane was designed by my father, Stefan
Brochocki, an aeronautical engineer at Canadair Ltd. Fred Bodek,
also of Canadair, assisted in designing some of the controls. (Fred later
worked for Boeing and was involved in designing the landing gear for the
747.) The BKB-1 was flown in Ontario, Canada, long before it came
to Seattle and well before Witold Kasper put his hand to the controls of
it. Kasper, as you probably know, was well known in the Seattle area
for his amazing stunt flying in the BKB in the 60's. He also claimed
to be its designer and builder, and generated an enormous amount of publicity
to that effect along with his BEKAS
and Kasper Wing based on the BKB.
The BKB was an experimental
design inspired by the Horten sailplane, and was created to serve a specific
need in Canadian gliding in the 50's. It was a high performance,
tailless aircraft with a glide ratio of 29:1, despite having a low aspect
ratio of 10:1. Dave Webb, several time Canadian gliding champion was one
of the test pilots who flew it. On one occasion, he was able to compare
its performance directly to that of his own Skylark 2B. Dave was
flying the BKB at the same time as a friend was flying the Skylark.
The BKB outperformed the other aircraft between thermals with a flatter
glide angle in the 50-75 knots region. (The documentation presented to
TWITT includes a comparison of its performance to that of the Fauvel. Polar
#1 Polar #2 )
It was most famous for
its alleged ability to perform controlled tumbles and recover; not
exactly what it was designed for, but perhaps, if true, a serendipitous
quirk (an aero-isoclinic wing perhaps?) that bears further investigation.
At the end of this presentation, you’ll see a very short film clip of the
BKB in flight and you may judge for yourself whether it is truly performing
the fabled tumbles. (Note: Since this presentation I have located two people
who claim to have seen it tumble, one of them being a pilot who flew the
BKB and performed the tumbles in it.)
At this point, it’s
worth it to recount a brief overview of events in the development and testing
of the sailplane BKB-1:
Dave Webb during an initial test flight.
THE BKB-1 STORY
The
BKB design concept began with Stefan Brochocki’s interest in gliding in
his native country of Poland in pre-war days He had become inspired
by the silhouette of the Horten glider and, over time, he came to realize
aspects of the Horten that could be improved upon. But it was not
until 1953 that he began to put his ideas on paper in the form of a design.
In Canada, in the 1950's,
Stefan belonged to various gliding clubs, in particular the Montreal Soaring
Council, which flew out of Hawkesbury, Ont. near the Quebec -Ontario border,
just on the edge of the Laurentian Mountains. Stefan was disappointed
by the lack of suitable aircraft to fly. Many of the gliders were
old and in need of repair, and there were too few of them to fill the needs
of the local gliding enthusiasts. It seemed that gliding in that
area was not exactly on the cutting edge of the sport. With his ideas
in mind of improving on the inspirational Horten, Stefan set out to design
a new glider which would suit the needs of his club.
Stefan’s new wing was
designed with the following objectives: to fill a gap in Eastern
Ontario soaring by providing a design that strayed from the traditional
design; was inexpensive to build; easy to handle in flight, and; easy to
maintain. For a more aerodynamic explanation of the design objectives,
I would refer you to Stefan’s letter of Nov. 10, 1961, to Dr. J.J. Cornish
at Mississippi State University. This and other documents are included
in the material I will be leaving with TWITT for its library.
His design was met with
enthusiasm at Canadair Ltd. where he was employed, and where he immediately
attracted two volunteers in forming a partnership for the construction
of the new craft - Fred Bodek, who worked in the design department, and
Witold Kasprzyk, an inspector, working as a liaison between design and
manufacturing. For Brochocki and Kasprzyk (later known as Kasper),
it was a renewal of an old acquaintance, the latter having been Stefan’s
gliding instructor in Poland. In 1954 the partnership was formed, each
member with his specific duties. Bodek and Kasprzyk were to finance
the project, Stefan to provide design and drawings and create the type
record, while Bodek was to provide some of the excellent illustrations
and some design of the craft’s technical features. All three were
to be involved in the construction which started in 1955 in Kasprzyk’s
basement.
In 1956, negotiations
with the Canadian Department of Transport began for inspection and
certification of airworthiness. The prototype BKB-1
was completed in October of 1957, and revisions to the type record were
made. With negotiations continuing through that year, the new wing
was ready for testing. It received its temporary Certificate
of Registration (CF-ZDK-X) and flight permit in September of 1959.
(Note: Though considerable testing and modification was done in Canada
it was never considered by my father to be complete and consequently, a
permanent certificate was never issued.)
Kasprzyk had moved to
Seattle in 1958, before the construction was completed and a new location
had to be found to complete the work. The two remaining partners
carried on with the work and the testing. Although short hops piloted
by Stan Rys and Stefan were made with a car tow in the fall of ‘58, the
BKB-1 did not make its official first flight until the fall of 1959, piloted
by Dave Marsden of the National Research Council. Tragically, Stefan
never flew the BKB again due to financial reasons and insurance costs.
A slight injury sustained on one of those first “car hops” made an impact-
he had a young family to support. He could not afford to have something
happen to him.
Further testing was
carried on by Marsden. Modifications and adjustments were made on
an on-going basis, all of which are described in the Fight Test Reports
section of this compilation. (Click here to see
the wing tip rudders.) Bodek also flew the wing and said it was beautiful
to fly. Dave Webb, Canadian gliding champion,
was among the pilots who took it to the air. He completed a number
of test flights, many of them lengthy. He was impressed with its
potential and its amazing capabilities for such a low aspect ratio.
But, he said, it was not a craft for beginners and suggested modifications,
subsequently carried out, to the skid and towing arrangement, which
were needed to improve take-off and landing, and to prevent “porpoising”
on rough terrain. (I believe there were further modifications made
to the skid later.) Years later, he was to commission Stefan to design
an aluminum version to be flown in competition. This design exists
but Dave was not able to continue with his plans, so the design sits, not
quite finalized, in Stefan’s possession. Other pilots flying the
BKB included George Adams, Gordon Hicks, and Hiller Kurlents.
Correspondence continued
between Kasprzyk, now officially Kasper, and Stefan for several years.
In 1960, from Kasper’s letters, Stefan became aware that he was involved
in another construction project and was planning to use the design and
data of the BKB as a basis for development. To protect his and Bodek’s
interests and the integrity of the design, Stefan drew up a document (A-1
in
the collection of documents presented to TWITT) which prohibited Kasper
from doing so. This important document, signed by Kasper, is in Stefan’s
possession. It became evident later, that Kasper completely ignored
this agreement, and repeatedly violated its clauses.
Bodek, too, eventually
moved to Seattle in 1960, to work at Boeing , and later worked in Barbados
in charge of engineering on a windmill project for the Brace Institute
of McGill University. Left on his own to sustain the project, Stefan
found himself overworked. His weekends were spent at the Pendleton
Gliding Club, 90 miles away, his evenings working on drawings and
modifications. The absences were taking a toll on his family.
They had just purchased a new home, requiring landscaping and all the work
that a new home entails. For financial reasons, insurance for him
to continue test flying was out of the question. Without the financial
backing and assistance of his partners, Stefan’s resources of time, money,
and energy were exhausted, and he had to make a decision about the future
of his glider.
Kasper had been badgering
him for years for news of the testing; Stefan was weary of his demands
and decided that he would let the glider move to Seattle for further testing
and the continued tuning that had been suggested in the test flight reports.
In 1964, the Canadian registration was canceled and ownership was transferred
to Kasper. It was a difficult decision, and one that was received
with mixed feelings by his family. It was also a decision Stefan
would come to regret in several ways. On the brighter side, he knew
the BKB would not sit idle and development and testing hopefully would
continue.
In 1960, Stefan was
invited by Bev Shenstone, engineer with BEA London and British flying guru,
to present a paper on the BKB
to the 8th OSTIV Congress in Cologne, Germany. The paper, entitled
A
New Tailless Sailplane was presented by Bev in Stefan’s stead in June
of 1960. It was subsequently published in Swiss Aero Revue.
Bev Shenstone was one of the most enthusiastic promoters of Stefan’s work
and arranged in 1959 for the inclusion of his design in Jayne’s and The
World’s Sailplanes, Vol.2.
It is worth noting that
at the same OSTIV Congress in 1960, Dezsö Györgyfalvy, of the
Aerophysics Dept. of Mississippi State University, presented a paper entitled
Performance
Analysis of the Horten IV Flying Wing. Stefan felt vindicated
by this critique of the Horten, for it cited many of the flaws that he
had set out to overcome when he designed the BKB-1.
During these years,
Stefan Brochocki received requests from all over the globe for information
on the BKB. It had been well received internationally. Stefan’s
reputation as an aircraft designer grew with it. Requests were received
for his advice on other aircraft design projects as well. In 1961,
Professor Barry Neumann of McGill University asked Stefan to present at
a Fluid Motion Seminar in the Dept. of Aeronautical Engineering at McGill.
With pilot and friend, George Adams, he presented Introduction to a
Canadian Sailplane.
Also in 1961,
Professor Neumann became the liaison between Stefan’s group and Dr. J.J.Cornish
to test the craft at Mississippi State University, where work had been
done to test the Horten. After a great deal of information sharing
and correspondence, the effort had to be dropped because of logistics problems,
distance and trailing being some. (Please see the correspondence sections
of the document binder.)
Then in 1963, a disturbing
letter arrived from Fred Bodek in Barbados shortly after Kasper had sent
Al Wilson to Canada to pick up the plane. The letter described an
article in the Boeing News. Despite the international interest surrounding
Brochocki and the BKB, the Boeing news had carried a story of Kasper and
“his” glider, the BKB-1, (technically he did own it). The article,
entitled "Employee’s Glider Can’t Fly- But It Does", has Kasper claiming,
“My design is so stable, it can become boring to fly”. He then proceeds
to explain how he conceived of and developed the design over many years
through some process of observing nature. No credit was given to
his former partners. He didn’t even mention their names. Brochocki
and Bodek were not amused, but then, the Boeing News was just an employees’
paper, and perhaps Kasper had just been carried away in his enthusiasm.
After all, the work of the BKB and its designer and the partnership that
produced it were already well-documented in respected publications, and
Stefan had Kasper’s signature regarding the matter. Stefan’s interest
was now consumed by sailboat design.
During this time Kasper
and test pilot, Al Wilson, continued to fly the aircraft in Seattle.
They made some adjustments to position of controls, reduced the hinge moment
of the rudder to reduce pedal forces, and made the seat position adjustable.
(Click here for picture of tufted wing in flight.)
Kasper was a gifted
pilot who did some incredible (perhaps foolhardy?) aerobatic flying in
the BKB and, if indeed the BKB did exhibit controllable tumbling as he
claimed, then it is to his credit that he was able to discover that.
It is all the more incredible that he was able to license it for aerobatics.
The BKB was not designed for aerobatics. You may recall that Stefan’s
original objective was to design an aircraft that was stable in flight.
Since aircraft as a rule are not known to recover from a tumble and the
ensuing stall, he had striven to avoid the possibility of tumbling in his
design. Aircraft must be built to withstand much stronger forces
to be licensed for aerobatics (at least in Canada this is true), and the
BKB was not designed for this category of flight. It appears that
by making stability the first priority, the BKB became sufficiently stable
to recover from a tumble, (if indeed it did tumble).
Not much was heard about
the BKB in the years following 1965, the last dated correspondence from
Kasper. Soaring Magazine listed the BKB as designed by Stefan
Brochocki and manufactured by the partnership in its May 1964, Directory
of Active Sailplanes in the United States. It appeared that Kasper’s
design claims were either forgotten or generally disbelieved. However
the Directory did mention that both Kasper and his test pilot, Al Wilson
were individually working on their own designs based on the BKB.
Stefan did make a presentation to the MacDonald
College in St-Anne de Bellevue, Quebec on behave of his local EAA chapter
giving some additional background on the BKB design.
Curtis McPhail, a pilot
for Northwest Airlines, was killed in a crash in 1971, while piloting
the BKB at Canaday Airport in Arlington, Washington. The story was
reported in the Seattle Glider Council publication, Towline, and
mentioned a brief history of the glider and the partnership that developed
it. Stefan Brochocki was devastated at the loss of life. He
tried to obtain details of the crash but nothing was received from Kasper.
To this day he has been unable to ascertain the cause of the accident and
subsequent loss of the pilot’s life. He has never come to terms with
it. Accidents can be expected in a risky sport, and somehow one can
deal with them. But being left in the dark about the details is haunting
and leaves no peace of mind in the long run. (TWITT
library has provided one version of details of the crash.)
More stories began to
surface about Kasper’s claims regarding the BKB. In the Post-Intelligencer
( date & location unknown), he claims to be the developer of
the control system and the “elevons”, special adaptations of the
wing designed by Brochocki. He makes further and greater claims in
Soaring
(Nov 1969) despite the magazine’s previously- published crediting of the
design to Brochocki. Lengthy articles were featured in US Sport
Aviation Magazine (July 1973, "Flight Testing the Bekas-N") and Canadian
Sport Aviation Magazine (Spring 1984, "Remarkable L/D Achieved by Short-span
Tailless Sailplane") repeated in great detail Kasper’s claims to the unique
design of the BKB. Stefan wrote to publishers of the latter to set
the record straight and was ignored.
In 1997, Bob Gairns
of the Montreal Soaring Council wrote Stefan to notify him that Soaring
(July 1997) had again published information describing Kasper as the designer
of the BKB. Bob had contacted Soaring and furnished them with
documents (1955 article in Free Flight by Stefan Brochocki) to refute
this. He, too, never received an acknowledgment or thanks.
(Bob Gairns passed away, tragically, last year at the age of 80, when the
glider he was flying crashed.) Kasper did indeed introduce other
designs; his well-publicized Bekas and Kasper Wing. The Bekas
was essentially the BKB. Kasper had attempted to increase its performance
by increasing the wing span. By doing so, he ran into some difficulty
in increasing the already low aspect ratio, causing instability.
The wing became more elastic and lost its aero-isoclinic properties.
As Stefan describes this situation, it became a case of the airplane flying
the pilot. Kasper called it dynamic soaring. (Since this presentation
I was able to locate a set of Kasper’s plans for the Bekas and BKB-1a,
included together on the same paper. I laid one of Stefan’s original
drawings of the BKB-1 wing over the top of Kasper’s drawing of the same
feature: they matched perfectly. Except for some gussets and
modifications to the wing-tip rudders, it was essentially the same drawing
with some details removed and some added. The extra length for the
Bekas wing was not there in the drawing.)
All of these aircraft
were developed from concepts initiated and tested on the BKB-1, violating
design rights of the originator and contradicting Kasper’s signed agreement
with Stefan Brochocki. Over the years numerous articles continued
to appear linking Kasper, and Kasper alone to the BKB-1. Present
endeavors to set the record straight were initiated in 1994 by myself,
and have, until the past year with the help of the Internet, proven difficult.
Many individuals and organizations are now showing an interest in the real
BKB story.
It is clear that despite
the fact that the BKB no longer exists, there is much left to unfold in
its story. The record needs to be set straight. Stefan Brochocki,
his family, and those who have worked with him over the years and lent
their invaluable assistance in many ways don’t agree with Kasper’s claim;
“Only a stupid fellow
tells the truth.” (Seattle Times, Sunday, Oct. 7, 1971).
If only Kasper were
still here to face it!
Dave Webb during an initial test flight.
THE FUTURE
It’s clear that a great deal of public information currently
available concerning the BKB is erroneous, and what I seek to accomplish
is the absolute and sole connection of Stefan Brochocki with the aerodynamic
design of the aircraft, and in conjunction with Bodek in some mechanical
aspects, in print and in the minds of the interested public. It must
also be similarly acknowledged that subsequent designs by Witold Kasper
with aspects resembling those of the BKB were based on that original design
and violated an agreement he had made with Stefan Brochocki. Fred
Bodek’s contribution to the production as a whole must also be recognized.
Patents have been taken
out by Kasper on various details of the BKB design. These patents
are now being investigated with a view to the origins of their subject
matter.
I don’t seek to discredit
Mr. Kasper for any legitimate contributions he may have made towards the
refinement of the BKB design or performance, and I acknowledge the inspired
flying he has done to test and promote this experimental aircraft. The
fact that he failed to credit his partners while heaping praise upon himself
alone is repugnant and incomprehensible. In assigning credit for
the work on the BKB, Brochocki always referred to it as a partnership.
In his address to the McGill Aeronautics Department in 1961 he wrote:
“Speaking of the BKB-1 sailplane I am also speaking on behalf of my partners,
Witold Kasprzyk and Fred Bodek, without whom this project would not have
reached the flying stage.” Let’s restore Brochocki and Bodek to their
deserved place in the story of the BKB.
The whole matter raises
many questions, and it would be rewarding if there were parties interested
enough to follow up. For example, I am unaware if Kasper’s work was ever
submitted for rigorous peer review. What I’ve seen in print generally
appears to focus on Kasper’s claims or those of public relations man, Horst
Petzold. It’s quite possible that there are performance analyses
that my family has not seen. What we have been made aware of has
generally been sent to us by concerned individuals who had happened upon
one of Mr. Kasper’s articles in some gliding magazine. I would welcome
other resources, and I haven’t yet had the time to access TWITT’s library.
The BKB testing to ascertain
its performance in relation to the original objectives of the designer
was never fully completed, and it is regrettable that the rigorous testing
it was to receive at Mississippi State University never came to pass. Consequently,
there may have been design modifications still required but never attempted.
After leaving Canada the BKB was commandeered for aerobatic uses.
It became a stunt flyer, and it appears that its other capabilities, potential,
or use as a tool in design research became of secondary importance to its
role as a vehicle for publicity. This is not to say that the publicity
was without merit, it just overshadowed the original objectives of the
design.
What really happened
to the BKB in America? What had it accomplished? What caused
it’s fatal crash? Was it properly maintained, and how did it become
licenced for aerobatics? Were there other mishaps before the final
one? What happened to it’s remains? It would be extremely satisfying
to Stefan Brochocki and his family to recover even a small piece of his
project. Both Bodek and Brochocki have many questions they would
like answered.
Having the opportunity
to speak to this distinguished and interesting group of TWITT members has
given all of us involved with the BKB the chance of hearing some answers
and of acknowledging the correct facts in the matter of the little Canadian
sailplane. There are many interested parties back home and across
the continent who are anxious to know the outcome, and who realize
your group’s potential to acknowledge the truth and to encourage us in
our endeavor. I thank you all.
Andy Kecskes of TWITT
deserves my most whole-hearted thanks for the hours of time he has spent
corresponding with me over the past 10 months and researching information
and links to assist me. Without his kind help and encouragement, I would
never have had this opportunity. And toJohn
Mitchell, your telephone call made me realize I was on the right track.
Many thanks.
I would also like to
extend my thanks to George Knight who has become a most valuable force
in this project. I could not continue without his technical knowledge,
assistance, and encouragement.
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