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Howard-Nebesar Transatlantic Twin Boom Aircraft Project

Stargazer2006

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I know I have been known here as a rather finnicky person when it comes to spelling names, but this is a perfect example of why it matters to spell names properly.

Previously I had tried to find this Mr. "Nesebar" but found nothing.

Until today when I accidentally happened on a Mr. R. J. Nebesar who appeared in somebody else's patent. And BINGO!!! After searching this name I found plenty of patents by him or referring to him.

This is why I urge all you forum members to make an effort when reproducing somebody's name on the forum, especially if these names are not from your own native language, because 1°) very quickly the mistakes spread all over the place, and 2°) they make future searches impossible.

Please can a moderator fix the mistake in the title and separate posts? There is also a mention in another post here: http://www.secretprojects.co.uk/forum/index.php/topic,20422.msg229141.html#msg229141

Thanks A LOT.
 

hesham

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Sorry for this miss spelling Skyblazer,


and we can detect the part on it here,to add in this thread.
 

Aubi

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Wow. It seems that the mysterious R.J. Nebesar is no-one else than dr. Robert Nebesář, radical but unsuccesfull designer of the Avia a.s. pro průmysl letecký. I just found a jstor page about an article written by "Robert J. Nebesar" of "Avia Aircraft Corp". https://www.jstor.org/stable/44467982?seq=1
Robert Nebesář spent some time in the early 30s in the USA, and was definitely influenced by it. For the Avia company, he projected Avia Av-51 and Av-57 three-engined passenger planes, very similar except for the wing placement, and Av-156 single-engined fast postal airplane. Both Av-57 and Av-156 were destroyed in crashes - in the same day. Av-51 high-wing passenger plane was rejected by the presumed customer, Czechoslovak Transport Company airlines, due to high vibrations, but still three machines were built and trough fictional Estonian customer supplied to the Republican Spain. His last know work in the Avia company was the B-158 bomber, interresting and modern airplane that also ended as prototype only. No other project of Nebesář is known to me. Presumably in 1938, after the Munich crisis (an maybe even before that), he emigrated to the Great Britain (he is mentioned as resident of Bristol in 1941) and later to the USA and started working on a transatlantic airplane design... https://patents.google.com/patent/USRE22029
I would check Václav Němeček and his Československá letadla, but this damn cat sleeping on my lap prevents me from reaching my library. Maybe later.

P.S.: Oh the irony: "Carrying from fourteen to sixteen passengers, the Aria(sic!) 57, with three 575 h.p. radials of "Cyclone" type, cruises at 180 m.p.h. Dr. Robert J. Nebesar, the designer of the machine, tells us he is quite satisfied with the results of test flights." That was before it killed everybody on board, obviously.


P.P:S.: Accordding to Němeček, Nebesář spent some time in the Martin, Lockheed and Consolidated companies and had complete trust of the Škoda company, owner of Avia. His first project was Avia 50, sort-of Lockheed Vega copy from 1931 and precursor to the Av-51, five-passenger machine with T-shaped tail surfaces and three Avia R-7 engines. Another Vega-like machine was Av-56 with one Avia Rr-29 radial engine, which after the engine switch to Avia HS 12Ybr led to afore-mentioned Av-156. The last project mentioned is Av-58, obviously a precursor for Av-158, a two-engined fixed-wheel monstrosity with Avia Rk-17 engines mostly similar to the LACAB Doryphore, if it was a low-wing monoplane. In 1937 Nebesář worked on Avia 63, Czech variant of Potez 636 with single tailplane instead of twin. Due to the immaturity of the original machine, licence negotiation fell and work stopped. And as I thought, in 1938/1939 Nebesář emigrated and spent some time with various small US companies, including Howard Aircraft Co. for which he designed "typically Nebesar-like overblown project, ... five-engined trans-atlantic twin-fuselage passenger plane Howard-Nebesar".
Sadly, this is the last mention of Nebesář I could find.
 
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Michal Ovcacik

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Wow. It seems that the mysterious R.J. Nebesar is no-one else than dr. Robert Nebesář, radical but unsuccesfull designer of the Avia a.s. pro průmysl letecký. I just found a jstor page about an article written by "Robert J. Nebesar" of "Avia Aircraft Corp". https://www.jstor.org/stable/44467982?seq=1
Robert Nebesář spent some time in the early 30s in the USA, and was definitely influenced by it. For the Avia company, he projected Avia Av-51 and Av-57 three-engined passenger planes, very similar except for the wing placement, and Av-156 single-engined fast postal airplane. Both Av-57 and Av-156 were destroyed in crashes - in the same day. Av-51 high-wing passenger plane was rejected by the presumed customer, Czechoslovak Transport Company airlines, due to high vibrations, but still three machines were built and trough fictional Estonian customer supplied to the Republican Spain. His last know work in the Avia company was the B-158 bomber, interresting and modern airplane that also ended as prototype only. No other project of Nebesář is known to me. Presumably in 1938, after the Munich crisis (an maybe even before that), he emigrated to the Great Britain (he is mentioned as resident of Bristol in 1941) and later to the USA and started working on a transatlantic airplane design... https://patents.google.com/patent/USRE22029
I would check Václav Němeček and his Československá letadla, but this damn cat sleeping on my lap prevents me from reaching my library. Maybe later.

P.S.: Oh the irony: "Carrying from fourteen to sixteen passengers, the Aria(sic!) 57, with three 575 h.p. radials of "Cyclone" type, cruises at 180 m.p.h. Dr. Robert J. Nebesar, the designer of the machine, tells us he is quite satisfied with the results of test flights." That was before it killed everybody on board, obviously.


P.P:S.: Accordding to Němeček, Nebesář spent some time in the Martin, Lockheed and Consolidated companies and had complete trust of the Škoda company, owner of Avia. His first project was Avia 50, sort-of Lockheed Vega copy from 1931 and precursor to the Av-51, five-passenger machine with T-shaped tail surfaces and three Avia R-7 engines. Another Vega-like machine was Av-56 with one Avia Rr-29 radial engine, which after the engine switch to Avia HS 12Ybr led to afore-mentioned Av-156. The last project mentioned is Av-58, obviously a precursor for Av-158, a two-engined fixed-wheel monstrosity with Avia Rk-17 engines mostly similar to the LACAB Doryphore, if it was a low-wing monoplane. In 1937 Nebesář worked on Avia 63, Czech variant of Potez 636 with single tailplane instead of twin. Due to the immaturity of the original machine, licence negotiation fell and work stopped. And as I thought, in 1938/1939 Nebesář emigrated and spent some time with various small US companies, including Howard Aircraft Co. for which he designed "typically Nebesar-like overblown project, ... five-engined trans-atlantic twin-fuselage passenger plane Howard-Nebesar".
Sadly, this is the last mention of Nebesář I could find.
Hello Aubi,
just incidentally came across your detailed account on this forum...
Mr Nebesar's family emigrated to the US and he went to Bristol, Virginia, not Bristol in the UK.
After a short spell he started working for another company called Universal Moulded Products Corp. at Bristol, Va., and was an author of many patents related to aircraft manufacture.
Regards
Michal Ovcacik
 

hesham

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Welcome aboard Michal Ovcacik,

and I check from this title (Universal Moulded Products Corp.),but I didn't
find a patent for it,can you guide me to direct link,and thanks.
 

Sarastro

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Hi,

I dare to the person of Dr. Nebesáře and his work in Czechoslovakia in the 1930s quote a short passage from the publication JAKAB Czechoslovak Prototypes Part 2 by Mr. Kučera:

„Within a few years, (first half of the thirties) Avia set upon developing modern all-metal aircraft - i.e. with stressed-skin structure, the so-called semi-monocoque structure. In this decision, the managem of Skoda and its subsidiary Avia was influenced by the young Czech technician, Dr. Ing. Robert Nebesář, who had worked in the USA gaining experience at Glenn L. Martin, Lockheed Division of Detroit Aircraft Corp, and Consolidated Aircraft. Shortly after his arrival home in 1930, he became a leader of a second design team at Avia's Aviation Division, focusing on all-metal construction, initially for commercial aircraft.
At this time, the entire Czechoslovak aircraft industry was beginning to consider the all-metal cantilever monoplane. But in all fairness, it was not prepared in terms of design, strength analysis, and technologies. Some home manufacturers tried to gain experience with cantilever metal wing from abroad - e.g. Aero at the German firm Rohrbach. The difficulties of going one's own way was bitterly felt by the Letov factory with their unsuccessful Š-32 and Š-33. The designs of Dr. Ing. Nebesář at Avia also encountered major problems. It is not easy to judge whether the lack of experience in the technical disciplines, including the safe lifetime and reliability of duralumin structures, or the very innovative designs of Nebesář, played the main role in these difficulties. Nevertheless, Avia was the first in Czechoslovakia to use retractable undercarriage, wing flaps, and other novel approaches in design. The initial aircraft of this Avia group had metal wings, but still covered by fabric. Surprisingly, despite serious failures of Nebesář's designs, the Škoda leadership continued to give him both morale and financial support."
 
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