Flying wing as cheap and simple option for basic fun flying.

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Norman

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-same little correction="BKB1"...

"BKB1-A" =modyfied (wingtips) into Aerobatic tailless glider=permission for full manouvers at any altitude !

"BEKAS-N"=exclusive property=thanks ellastic wings=possibility in exerting
energy from horisontal gusts =soaring in Athermic weather !!!
How many people has it killed?
 
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Vigilant1

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The BKB1-A is a good example of a “Flying wing as cheap and simple option for basic fun flying.” It was designed as a post WWII trainer as a simple build for flying club students to have a good performing glider for
solo students to build time.
I would think an ideal trainer would have basic handling attributes similar to the later planes a student will fly. Not identical, but close enough so that there's minimal 'unlearning" needed and so that the "primacy' principle works to the student's advantage when needed (novel or unexpected situations, etc). Does early training in a flying wing do a good job of preparing a student for later flying in the 99% of regular aircraft that have tail surfaces?
 
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henryk

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How many people has it killed?

=TU-104 ?

(big mistaces in towing organization=see microvideo=22 seconds... !)

=sunday car towings=5 + ! (h/s=2/200 ,L/D= 100 !!!)
 

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WINGITIS

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-same little correction="BKB1"...

"BKB1-A" =modyfied (wingtips) into Aerobatic tailless glider=permission for full manouvers at any altitude !

"BEKAS-N"=exclusive property=thanks ellastic wings=possibility in exerting
energy from horisontal gusts =soaring in Athermic weather !!!



=more...

Now we know what "YUKYOUDOLLICK" means......
 

henryk

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How many people has it killed?
=after first GROUND "BANG" ==circa 2/3 of time==(overloud= - 4 "g"=- 40 m/s ^2) pilot cry by radio=

=I continue fly !!!!!

=disconection of tow line after wing spar break !!! =WILGA 104 momentally at circa 50 m high !!!
 

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jedi

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I would think an ideal trainer would have basic handling attributes similar to the later planes a student will fly. Not identical, but close enough so that there's minimal 'unlearning" needed and so that the "primacy' principle works to the student's advantage when needed (novel or unexpected situations, etc). Does early training in a flying wing do a good job of preparing a student for later flying in the 99% of regular aircraft that have tail surfaces?

I am not familiar with the accident of post # 2543 so will not comment on it. I also note that it was not a BEKAS but a redesign with entirely new structure.

The fatal crash of the only BECAS built was fairly certain to be caused by a very experienced pilot attempting a forward, negative G, tumble that the aircraft was not designed for and the pilot was sternly warned not to attempt; hardly a fault of the aircraft.

The "Kasperwing" Ultralight is very popular among its owners and is reported to have very good flying qualities. Aircraft flying qualities was high on the list of Kasperic.k's and the designers specifications. Kasperic.k freely recounted how he was given the only remaining example of a three off high peformance and dangerous sailplane for a world competition. The other two aircraft had each killed the two other contest pilots in stall spin accidents. Kasperick also crashed his glider in a stall spin accident but had learned enough from the other two fatalilties that he managed to survive.

The BEKAS was designed to be an excellent training glider and pilot reports on its handling were good. It was known for it's exceptional low speed flight characteristics. It was not known as having the negative flight characteristics of some other flying wings.

Stall spin accidents are among the most common causes of fatal accidents among glider pilots. The BEKAS and Cascade Ultralights have exceptional low speed control and are a giant step forward in stall spin safety.

I do not propose that I know or recall all the details of the BEKAS design, operation and history and welcome other comments and opinions. Additional comments are encouraged.
 

henryk

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(soft spar) was not a good idea.
BKB1-A (AR=10) ,
we have composite wings...

BEKAS1-N (Narrow) , AR=15,

BEKAS1-A ( 1.2 m chord ) crashed in 2013, permission to restore for museum.

BTW=dr Grzybowskis Father was made patent =Unsymmetrical Longeron=
optimal for BEKAS wing !
 

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henryk

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I am not familiar with the accident of po
=I am,very close !

-my English is very primitive=hard to explain all details...

=circa 300 KASPERWINGs flying,
V horisontal 20- 80 km/h,

=NO seriouse ingures !

Witold Kasprzyk /Kasper was survived classic glider stall/spin ,
NO crashes in many BKB1-A and BEKAS-N tests!

PS= Take off from water (20 HP !) 3-4 sec...

PS2=I was withstand circa 500 "g" overload on my old legs =

PS3= Bogdans last motorglider with BKB1-A wings too.
 

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jedi

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I believe I mis-spoke in Post # 2539 where I posted "The BKB1-A is a good example of a “Flying wing as cheap and simple option for basic fun flying.” The aircraft I was attempting to reference was the aircraft built in Toronto by the team referred to as BKB where the K was for Kasperick's contribution and the two Bs were for the other two contributors. I believe it was titled BEKAS when imported into the US. I would need to do more research to get all the Polish names and acronyms correct.

This aircraft is the source of the original "Kasper Wing" which Kasperick imported to Washington State. After modifying the wing tips and tip controls Kasperick did several airshows to demonstrate his characteristic tight loops that were actually a nose up tumble and amazingly short field landings (SL is STOL without the takeoff). This is the aircraft that had the wing structural failure attributed to the attempt by an airline pilot to do a negative tumble against the advise of several other pilots that had experience in the aircraft.

All of the following so called Kasper Wings were modified without input from the original designer. In my opinion attempts to improve the original design, with the possible exception of the modifications Kasperick made to the original example (or prototype), have compromised the original design. See my post #2535 on this list for comments on attempts to improve upon a good design intended for a specific design specification. The original design specification was to create an inexpensive, easy to build, safe training plane.

The first "B" is for the designer. His daughter Stephanie Brod....idcheck (no idea of proper spelling) has done considerable work to defend her dads design contribution which Kasperick has in general gotten credit for. The entire "Kasper Wing" and Kasperick history has a considerable amount of controversy about credit and blame that is questionable as to its validity.
 
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jedi

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Does early training in a flying wing do a good job of preparing a student for later flying in the 99% of regular aircraft that have tail surfaces?

Yes.

If the aircraft keeps the student alive by avoiding stall spin and landing accidents while expanding the operating envelope of the student it has made a significant contribution to the students knowledge/experience base. All the students will have had experience in a larger and heavier two seat training aircraft to experience conventional aircraft.
 

Norman

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I believe I mis-spoke in Post # 2539 where I posted "The BKB1-A is a good example of a “Flying wing as cheap and simple option for basic fun flying.” The aircraft I was attempting to reference was the aircraft built in Toronto by the team referred to as BKB where the K was for Kasperick's contribution and the two Bs were for the other two contributors. I believe it was titled BEKAS when imported into the US. I would need to do more research to get all the Polish names and acronyms correct.

This aircraft is the source of the original "Kasper Wing" which Kasperick imported to Washington State. After modifying the wing tips and tip controls Kasperick did several airshows to demonstrate his characteristic tight loops that were actually a nose up tumble and amazingly short field landings (SL is STOL without the takeoff). This is the aircraft that had the wing structural failure attributed to the attempt by an airline pilot to do a negative tumble against the advise of several other pilots that had experience in the aircraft.

All of the following so called Kasper Wings were modified without input from the original designer. In my opinion attempts to improve the original design, with the possible exception of the modifications Kasperick made to the original example (or prototype), have compromised the original design.

The first "B" is for the designer. His daughter Stephanie Brod....idcheck (no idea of proper spelling) has done considerable work to defend her dads design contribution which Kasperick has in general gotten credit for. The entire "Kasper Wing" and Kasperick history has a considerable amount of controversy about credit and blame that is questionable as to its validity.
BKB-1 stood for: Steffan Brochocki aeronautical engineer, Witold Kasprzyk technical translator, Fred Bodek mechanical engineer. It was the team's first and only design, thus the "1" in the name. The "A" was added by Kasper after he made the changes to the tip plates and elevons that Brochocki recommended when he transferred possession to Kasper. There shared ownership agreement was that each man would have it for a while and then give it to the next. Bodek was working in Barbados when his turn came so he left it with Kasper. The BEKAS was entirely Kasprzyk's design. It looks like he just stretched the wing of the BKB1 but it has a different airfoil, different pod, different tip fins, and different structure. The higher aspect ratio would have changed the stall characteristics and, if he didn't make the new spar substantially heavier, lowered G limit. Apparently several people had noticed that the wing flexed a lot and Kasper claimed that that was because it was intended harvest energy from horizontal gusts (dynamic souring). There is also some talk about an aero-isoclinic wing but that's actually a very hard thing to design for one guy working alone without access to a wind tunnel and a high end structural test lab. High AR swept wings tend to have an unstable (nose up) stall unless they have a lot of washout or some sort of stall delaying device see attached graph.
 

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jedi

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BKB stood for: Steffan Brochocki aeronautical engineer, Witold Kasprzyk technical translator, Fred Bodek mechanical engineer. The BEKAS was entirely Kasprzyk's design. It looks like he just stretched the wing of the BKB but it has a different airfoil, different pod, different tip fins, and different structure. The higher aspect ratio would have changed the stall characteristics and, if he didn't make the new spar substantially heavier, lowered G limit. Apparently several people had noticed that the wing flexed a lot and Kasper claimed that that was because it was intended harvest energy from horizontal gusts (dynamic souring). There is also some talk about an aero-isoclinic wing but that's actually a very hard thing to design for one guy working alone without access to a wind tunnel and a high end structural test lab. High AR swept wings tend to have an unstable (nose up) stall unless they have a lot of washout or some sort of stall delaying device see attached graph.

Norman,

Thanks for the clarification and corrections. The correct identification should have been BKB. Do you know if the BKB design was ever copied without modification. What is your impression of the original BKB design and Kasprzyk's modification to that aircraft?
 

henryk

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Witold Kasprzyk technical translator,
=Witold Anton Kasprzyk (1908-1994, Krakow) was student of Lwow Politechnical Institute...
was the best polish glider pilot, in 1947 wrote paper="New sailplane concept"
(DIANA 2 like!).

After escape to Sweden/Canada/BOING was modyfied BKB1 to Aerobatic ,
Unbelivable device =controlled tumblings,landings with Zero speed, Vertical Musch...
He was discovered VORTEX Flow=tremendous Cl

+ STATIC Stability and Contralibility !

BKB1-A can circle with Vx=10 m/s ,Vy=0.5 m/s (L/D=20 !!!)

Kaspers/Grosrucks KASPERWING can fly stabil at 5 m/s horisontal speed,
and landing vertically with simiral speed !!! Cl=Cx=5

-according "Kasprzyk technical translator"
Hi was operate with 12 (twelv)
 
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