Percival Gull - Designed By.............?

[avion ancien]

This may be a bit of an old chestnut and, if so, I crave forgiveness. But if it is, it does not seem to be an old chestnut that has yet been debated on this forum!

In the 1974 edition of 'British Civil Aircraft' A.J.Jackson says, in the first paragraph of the entry for the Percival Gull, that:

"Contrary to erroneous statements made in the first edition of this book, the Gull was designed solely by Edgar W. Percival, chief designer of Percival Aircraft Ltd., and not by, or with the assistance of others".

I'm sure that you'll agree that this is quite an apologetic statement, not typical of Jackson, and suggestive of one that has been written in response to a fairly robust solicitor's letter. But I don't possess the first edition of Jackson's work, so I don't know what he said there on the subject of credit for the design of the Gull. However I suspect that he may have given some design credit to Basil Henderson, R.W.Bound, C.H.Lowe-Wylde and possibly others.

Henderson was responsible for the design of the Hendy 302. If you take a look at a photo of that and then one of the prototype Gull, it is hard to avoid seeing similarities. The Hendy 302 was built for E.W.Percival. Arthur Ord-Hume says that:

"he [Percival] sketched out a layout around which ..... Henderson designed the Hendy 302".

Henderson was also a trailblazer when it came to monoplane wing design and his patented wing construction method was certainly used by Percival in the Gull. But, I wonder, how much more of the design of the Hendy 302 was employed in the prototype Gull?

Ord-Hume also talks of the first Gull being "sketched out by Percival" (shades of the Hendy 302?) at the time when Rowland Henry Bound joined the Percival Aircraft Co. Ltd. as head of design and he also says that:

"Bound was the person who put Percival's ideas into practice and fitted structures to sketches, stressed ideas into reliable reality".

So to what extent was the Gull Bound's work?

Percival having no manufacturing facility at the time when the Gull was designed, the prototype Gull was built by the company formed by C.H.Lowe-Wylde, namely British Aircraft Co. Ltd. (that's the BAC of Drone, rather than 1-11, fame) at Maidstone. Or was it? Jackson says that it was built:

"by E.W.Percival and his team in a small workshop at Maidstone, Kent, used previously by C.H. Lowe-Wylde".

So maybe there was input from Lowe-Wylde to the design of the Gull?

The upshot of this is that, at least at the outset, Percival may have been more of an 'ideas' man rather than an aeronautical designer capable of, singlehandedly, doing all the work required to enable the first Gull to fly and be the progenitor of one of the most famous lines of British light planes. However if that is so then, at least in latter years, it seems that he was unwilling to give credit to any others who may have contributed to the design of the Gull. If so, that's sad. Also if that's so, it's sad that Jackson had to be so obsequious in 1974. That Ord-Hume was less so, when he published 'British Light Aeroplanes' in 2000, might have had something to do with the fact that Percival had died in 1984.

So who did design the Gull? I'd be interested to hear the views of others, more knowledgeable and better read than me, concerning the inception, design and construction of this iconic light aeroplane.

[chumpy]

The 1987 book Percival & Hunting Aircraft by John Silvester, would tend to support the Ord-Hume view of things.

The author stating that the prototype Gull was built by the Lowe-Wylde concern at Maidstone. Another telling paragraph as to the origin of the species / Hendy 302 etc, mentions the repair of the prototype Gull following an accident in Scotland in 1932.

'The machine was returned to Brooklands for repair where, as constructional drawings were not available, the wings from the Hendy 302 (G-AAVT) were stripped down and used as a pattern to enable the wings of the Gull to be rebuilt in time for the Kings Cup'.

Edgar Percival not known for his modesty on all accounts, not that I wish to diminish his achievements in anyway.

Chumpy

[alertken]

AJJ Vol.2, 1960, P.182: Percival P.1 Gull Four: "After the Hendy 302 had made its successful impact on the aviation fraternity in 1930, Basil B. Henderson left Edgar W. Percival and was replaced by R.H.Bound who designed the 3 seat Percival Gull, successor to the 302...The Henderson patent cantilever mainplane was retained...prototype was built at Yate by G.Parnall & Co...first production batch of 24 Gulls was built at Yate in 1933 under sub-contract to the Percival A/C Co. Ltd, newly formed by E.W.Percival and L/C E.W.B.Leake."

[avion ancien]

It would be fascinating to know what exchange of words there was (assuming that words were exchanged ) between Percival and Jackson, in the period 1960 to 1974, which caused the latter to adopt a revisionist historian's position in the second edition of 'British Civil Aircraft'. Does anyone know by whom and where his papers are held?

[JDK]

Originally Posted by avion ancien

...to adopt a revisionist historian's position...'

Not the concept of 'revisionist historian' that I think most would recognise, just the very normal retreat from a potentially long, inconclusive and costly legal case. Happy to be corrected, but IIRC Percival worked hard to ensure his version of events was that published as far as was possible anywhere the story was told.

Quite a lot of history is suppressed that way while certain egos are alive, although many don't realise that.

I have some vague recollection of reading a reasonably detailed account of the saga. It was either in an issue of the modern Aeroplane magazine, or the National Museum of Australia's website. But beyond that, I really don't recall.

HTH!

[ozplane]

Didn't something similar happen with Alex Henshaw, Percival and the Mew Gull? The debate ended up with the pair refusing to talk to each other I believe.

[avion ancien]

Originally Posted by JDK

Not the concept of 'revisionist historian' that I think most would recognise, just the very normal retreat from a potentially long, inconclusive and costly legal case.

That's fair criticism. Perhaps the label I attached was a touch too strong. However the assumption is that it was a robust solicitor's letter, or suchlike, that caused Jackson to revise his stated views between 1960 and 1974. It would be interesting to know the actual facts behind this.

[G-ORDY]

OK guys - you've dragged me away from "SS3" for a while ...

I knew AJJ very well when I was publishing "Vintage Aircraft" magazine between 1976-1986 and as I was interested in Percival and his aircraft I made a point of asking about this one.

It was the threat of legal action which brought about the wording in the 2nd Edition - pure and simple.

One had to be very careful when publishing anything about Percival during his lifetime - I remember him ringing me at home one day after I'd published the photo of the prototype Gull under construction at Maidstone - a negative which I found in the photo archive of Motor Sport magazine and which Bill Boddy gave me permission to publish.

The story of the crash in Scotland is correct - that information came from Ron Paine who was working at Brooklands and who helped rebuild the wings - for which there were NO DRAWINGS! They stripped the fabric off the Hendy 302 and copied the structure! Read into that what you will.

The following is a copy of the first part of a feature article which I wrote for Issue # 30 of Vintage Aircraft and which was - I believe - the first time that all the facts had been brought together in one publication:

EDGAR PERCIVAL’S ideas on the design and construction of the ideal private owner’s aeroplane had evolved during the early and mid 192Os, a period of his life that had been spent conducting performance trials on a variety of types following his appointment to test pilot duties by the Air Ministry. The opportunity to put these ideas into practice came in 1929 with the design of the Hendy 302, a collaborative effort between Percival and Basil B. Henderson of the Hendy Aircraft Co. The latter company was little more than a design agency, although it did actually build the little Hendy 281 Hobo, G-AAIG, at its Shoreham premises most of the construction work on Hendy projects was subcontracted to manufacturers with spare capacity — a state which many concerns found themselves to be in at the end of the 1920s.

Precisely how deep was Percival’s involvement in the 302 is difficult to ascertain, the design brief was prepared by Percival and he claimed subsequently that “... I personally prepared approximately one third of the drawings for this machine.” What is clear is that the patent Hendy spar construction was incorporated into the wing and that the wing planform and airfoil section were both designed by Basil Henderson. Construction of the single example built was entrusted to George Parnall & Co. Ltd of Yate, near Bristol, and G-AAVT obtained its Certificate of Airworthiness on 27 June 1930.

The 302 was a sensationally clean design for its day being a low-wing cantilever monoplane powered by a single 105 hp Cirrus Hermes I and seating two persons in tandem. Percival’s idea was to display the type’s advanced performance in the 1930 King’s Cup Air Race which started and finished at Hanworth on 5 July that year. The field was the biggest ever, 101 entrants of which 88 eventually started, but he failed to beat the handicappers and the race was won by Miss Winifred Brown in an Avro Avian at a speed of 102.75 mph, the 302 putting up an average speed of 121.5 mph.

After the 302 had been flying for a few months Henderson and Percival appear to have gone their separate ways, Percival to design the Saro-Percival Mailplane, G-ABLI, which was built by Saunders-Roe Ltd at Cowes in 1931, and Henderson to prepare designs for N.A. de Bruyne (the Snark) and Bert Hinkler (the wing of the Ibis amphibian). Don L. Brown, who was involved with the Miles brothers at Shoreham at this time, stated in 1948 that Henderson did, in fact, prepare a design for a three-seat version of the 302, known as the 311, and that it was this aircraft which eventually appeared as the Percival Gull in 1932.

The precise origins of the Gull led to some acrimonious letters published in The Aeroplane during 1932. Percival was at pains to point out that Henderson was in no way connected with the Percival Aircraft Company Ltd recently formed with himself and Lt.Cdr E.W.B. Leake as directors plus R.H. Bound as chief draughtsman — and that the Gull, with the exception of the patent Hendy spar had been ‘... completely designed, drawn and stressed in these offices without any outside assistance.’ Henderson’s reply to this was to suggest that perhaps Percival had ‘. . . forgotten that the Hendy Aircraft Co. designed and supplied him with the complete drawings of not only the spar structure but of the entire wing structure...? The first Gull which was built (and thus presumably is the “Type Aircraft”) was granted a C of A as an aircraft subsequent to the Hendy 302, and consequently did not have to go to Martlesham Heath as would be necessary for a new type.’ Percival’s closing comments stated that between 80 and 90% of the drawings supplied by Henderson had been redrawn and modified in the Percival D.O. No mention is made of the part played by R.H. Bound, although some authorities have suggested that he designed the Gull. Percival himself stated categorically that it was entirely his own design and one which he had prepared solely and not with the assistance of others. Bound had previously worked with Hinkler on the Ibis from 1929 to 1931, he left the Percival Aircraft Company in 1935 and his place was taken by A.A. Bage.

The prototype Gull, G-ABUR, was built by the British Aircraft Company Ltd at its works at Maidstone, Kent, and is believed to have been test flown by Percival at the small aerodrome at Malling - now absorbed into the present West Malling aerodrome. The correct designation for this aircraft is the Percival Type D.1 Gull Four and in its initial form it was powered by a 130 hp Cirrus Hermes lv. Its first public appearance was in the 1932 King’s Cup Air Race which was held over 8 - 9 July and in which it put up an average speed of 142.73 mph, closely matching the speed of 145 mph which its predecessor the Hendy 302 had achieved in the London - Newcastle Race the previous year. What was never made public at the time was the fact that G-ABUR was almost totally destroyed in a forced landing accident a few weeks before the race. Percival -- anxious that the type should be seen in this most prestigious of races insisted that it was rebuilt and the work was carried out with considerable secrecy by Brooklands Aviation Ltd. What is most interesting is the fact that no drawings were available when it came for the wings to be rebuilt and as a last resort the fabric was removed from the wings of the Hendy 302, which happened to be at Brooklands at the time, and the structure was copied exactly in order to manufacture a new pair of wings for the Gull. This information came from Ron Paine, who worked on the Gull at the time, and who clearly recalls that it was only by a stroke of fortune that they could do the work anyway, this being that Vickers Ltd had just laid off a large number of carpenters following the cancellation of an order for Virginias and these were rapidly contracted to carry out much of the rebuilding of the Gull.

And here are some photos:



The man himself with the Hendy 302 in the 1930 Kings Cup Air Race - look at the hood design and neat little curved rear window and compare with the Gull photos below.



The prototype under construction at Lowe-Wylde's Maidstone workshop in 1932.



Probably an early test flight from Malling - compare canopy etc with the Hendy 302.



Practice flight for the 1932 King's Cup Air Race after the Brooklands rebuild, Percival at the controls - photo from Alex Henshaw.

I hope that clears it up for you - if only we could track down any relatives of Basil Henderson - he went to Parnalls and designed Frazer-Nash gun-turrets.

BTW - Anyone know what the Percival Types A, B and C were and why did his c/n's always start at 20? (It's not a quiz ... a don't know either answer!)

[avion ancien]

God bless you, Mr Riley, every one of you - and may you have a very merry Christmas!

Do you know the where A.J.Jackson's papers are archived? Are they at Brooklands along with his photographic collection?

[chumpy]

Interesting to hear G-ORDY's thoughts re Percival's litigious nature, perhaps this is why there was never a Putnam 'Percival' volume?..surely derserving of one in my opinion.

According to the Silvester book, 'For some reason known only to himself, Percival always chose to start his production numbers at 20' ...I guess we will never know!

[Mark_pilkington]

Percival Gull - designed by.............? "Percival - based on a general layout developed jointly with Henderson and Miles as the Hendy 302, and incorporating the Henderson cantilever wing spar design developed in the same airframe."

Some interesting information from Flight 1930 and Flight 1932, that seems to clearly support the above answer.

http://www.flightglobal.com/pdfarchi...0-%201368.html

DESIGNED by Mr. Basil B. Henderson, the " Hendy 302 " is a low-wing
*-' cantilever monoplane cabin machine intended for the private owner.
The machine incorporates in its wing construction some unusual and
patented features of which Mr. Henderson is the inventor. It is well known
that with cantilever wings it is more difficult to provide torsional stiffness
than adequate strength in bending, and the Henderson system of wing construction,
here carried out in wood but easily adapted to metal construction, is
designed to give great torsional stiffness. Fundamentally, the system consists
in duplicating the internal drag bracing of the wing and placing one set
of bracing on the upper faces of the spars and one on the lower. The bracing
itself consists, in the "302," of crosses or " X " members of wood, attached by
three-ply gussets to the top and bottom faces of the spars. Thus the spars
and duplicate bracing crosses form a sort of box which is very rigid in torsion,
and experience with two machines has shown that the Henderson system of
wing construction is not only strong but also reasonably light.
The " Hendy 302 " is a monoplane of very clean lines. The first machine
was rushed through in time for the King's Cup Race, and although bad
course-keeping prevented the machine from showing what it could do, the
speed over one stage of the course was such as to demonstrate that the " 302 "
is very fast, the maximum being a little over 130 m.p.h. Cruising at 1,900
r.p.m., the machine flies at 112 m.p.h.
Structurally, the " Hendy 302 " is mainly of wood construction, this
being simple, light and cheap when machines are being built in fairly small
quantities. Mr. Henderson and Captain Percival are now arranging for the machine to be built in considerable numbers, and if later it should be found advisable to produce a metal version there is no great difficulty in doing so.
The cabin of the machine is roomy and well lighted by large windows in
the sides and roof, and the view, particularly from the front cockpit is good,
much better than one would expect. The front seat is far enough forward
to enable the pilot to look over the leading edge, and the taper of the wings
is such that towards the tips they obstruct the lateral downward view to a
surprisingly small extent. The cabin top could, if desired, be removed and
the machine used as an open tourer, but the absence of draught and noise
which the cabin top affords makes it unlikely that anyone would, after trying
the machine, wish to do away with the cabin.
The engine of the " 302 " is a " Cirrus-Hermes II," completely cowled in.
The smooth and narrow top of the cowling obstructs the view but little, but
if a purchaser should so desire there should be no difficulty in fitting an
inverted engine, either the inverted " Hermes " or the " Gipsy III." The
petrol tanks are placed in the wing, and fuel is supplied to the engine by
pump.

http://www.flightglobal.com/pdfarchi...0-%200988.html

The " Hobo " was built in 1929. Mr.
Henderson's programme included testing
out the new spar on larger machines, either
in wood or, if possible, in metal, the principle
of the spar design lending itself very well
to all-metal construction. In the meantime,
Capt. E. W. Percival was interested in
machines suitable for private owners, and
was keen on getting a machine to fly in the
King's Cup Air Race. The next step in
Mr. Henderson's programme was a two-seater
development of the little " Hobo," and
the general " scheme " appealed to Capt.
Percival. The upshot was that he decided
to join forces with Henderson and Miles,
they to do the actual design work, calculations,
etc., and Percival to contribute practical
advice out of his long and varied experience
of aircraft at home and in Australia A
contract was entered into with George
Parnall of Bristol for the construction of the
machine, and work was begun at once, as
was very necessary in view of the fact
that there was but four months in which
to design and build the machine and test
it out in readiness for the King's Cup Race.
In the experience of every aircraft designer
it happens now and then that a certain
prototype is absolutely " right " from the
very start, and when that happens the final
result is always very much better than in the
case of a new type which has to have this,
that and the other altered before it is absolutely
"right." The "Hendy" 302, as
the new two-seater was called, proved
one of these instances. When it came to
be tested it did all that was expected of it
in the way of performance—or a little better.
It appeared to have no vices, and its controls
were effective over the whole speed range.
In the King's Cup race, as we have previously
pointed out, compass trouble prevented a
was not " placed." Had the same average
speed been maintained as that made good
from London to Manchester, the " Hendy "
302 would have secured 2nd place. That
was not to be, but those who watched closely
the performance of the various machines
realised that in the " Hendy" 302 one had
a new type with an obviously good performance.
It could not have beaten Miss
Brown, and so on its handicap could not
have won the race. But had it secured
second place this would have been an excellent
advertisement for the machine. There
is no reason to doubt, however, /that when
the " Hendy " 302 is placed on the market
it will find a ready sale, its performance
and general qualities being sufficient to sell it,
even without the advertisement of winning
the race.
The " Hendy " 302 is a two-seater, lowwing
cantilever monoplane, with the occupants
protected by a hinged cabin top.

However there does seem to be some differences in the two designs, the photos and drawing in Flight shows the Hendy to be a slightly smaller aircraft at 22' 10" and with a wingspan of 35' and area of 163 sqft, as compared to the Gull at 24' 8" and a wingspan of 36' and a wing area of 169 sqft, and the Gull appears to have been designed from the outset with folding wings, with no mention of that feature on the Hendy?

The following dimensions are taken from 3-D drawings of both types in the 1930 and 1932 Flight Magazine links below.

Hendy 302 - Percival Gull
Length 22' 10" - 24' 8"
Wing Span 35' - 36'
Wheel Track 6' 8" - 6' 9"
Wing Cord 5' 9" - 5' 10"
Wing Area 163 - 169
Aileron Area 15 - 14
Tailplane Area 15.3 - 16.75
Fin Area 4 - 4.16
Rudder Area 8 - 7.75
Elevator Area 10.2 - 10.4



http://www.flightglobal.com/pdfarchi...0-%200987.html

Interestingly, the complex wing bracing between the spar in the wing outer panels of the Hendy shown in this page of the 1930 Flight certainly bears some resemblance to the Gull wings as shown in the later photos below, at least in the spar bracing, which is evidence of the Henty cantilever spar design, but that seemed openly acknowledged in the 1932 Flight article on the Gull.

http://www.flightglobal.com/pdfarchi...0-%200986.html

Structurally the Percival " Gull " is a very straightforward
piece of work. The fuselage is a " box " composed
of light spruce stringers and struts, the whole covered
with a three-ply skin. The cantilever wing incorporates
the Hendy Patent wing construction, which consists of two
main spars braced in the planes of their upper and lower
flanges by a series of lattice ties. This construction gives
a wing which is particularly strong in torsion.

I assume the information for the Flight article on the Gull was provided by, or vetted by Percival at the time?


http://www.flightglobal.com/pdfarchi...0-%200756.html

It would seem clear that Percival had some relationship with Henderson and the Hendy 302, and an that an apparant intention to put that aircraft into production was superceded by the creation of a company by Percival and his investors to build the Gull. The Gull is clearly an evolution of the design layout of the Hendy 302, and seems to have at least the Hendy wing spar design acknowledged in 1932 in Flight.

The Gull folding wing appears to have resulted in some changes to at least the wing outer design, as compared to the Hendy, as the wing and aileron areas, spans and cords are not the same, or even in scale between each type, ie the Gull has a bigger wing but smaller ailerons, and so while the Gull wing may have used the Henty spar design there must be rib etc changes in the Gull wing outers, I think it might be right to claim it as a different wing, while acknowledging spar design from Henty?





Its unclear from Flight if the 1932 Gull prototype actually had flaps, but the flap boxes that lift to allow the wing to fold are clearly in place on the prototype and flight 3-d drawing, and I suspect may have been designed as flaps from the outset? as its a feature acknowledged elsewhere of the Gull series.



Obviously there seems a clear evolutionary design layout link between the Hendy 302 and the Percival Gull along with clear acknowledgement of the wing centre-section design of the spar/bracing structure, if Percival is acknowledged elsewhere in providing the general layout of the Hendy 302, he may consider the Gull to be his own design from that point of view, regardless of "re-design" of the structure.

Features such as the cockpit canopy and rear window may well have been his own design contributions to the Hendy?, it is difficult to prove such details nearly 80 years later, when the principals are departed and such details not recorded.

However in 1930 and 1932 Flight Magazine appeared able to publish such details without any apparant legal challenge or threats, and I assume the details for Flight regarding the Hendy 302 in 1930, and the Gull in 1932, would have been supplied by and/or agreed to by Percival and Hendy in 1930, and Percival himself in 1932?

I have seen private letters in Australia from Edgar Percival on this issue in the 1980's, but havent seen the correspondance to Aeroplane Monthly quoted by G-ORDY above, ’

Percival’s closing comments stated that between 80 and 90% of the drawings supplied by Henderson had been redrawn and modified in the Percival D.O.

, however with the folding wing and flaps, installation of the two wing fuel tanks etc it is quite believable that any wing drawings provided by Henderson based on the Hendy 302 would be substantially different in the wing outer panel area to the Gull.

Other than Percival perhaps trying to minimise acknowledgement of Henderson's contributions, I dont see anything inconsistant in the original Flight stories of the 1930's and what Percival admits in that comment?


As greater concern however is the reliance on the following testimony without apparant question? to argue the "sameness" of design.

The story of the crash in Scotland is correct - that information came from Ron Paine who was working at Brooklands and who helped rebuild the wings - for which there were NO DRAWINGS! They stripped the fabric off the Hendy 302 and copied the structure! Read into that what you will.

"What was never made public at the time was the fact that G-ABUR was almost totally destroyed in a forced landing accident a few weeks before the race. Percival -- anxious that the type should be seen in this most prestigious of races insisted that it was rebuilt and the work was carried out with considerable secrecy by Brooklands Aviation Ltd. What is most interesting is the fact that no drawings were available when it came for the wings to be rebuilt and as a last resort the fabric was removed from the wings of the Hendy 302, which happened to be at Brooklands at the time, and the structure was copied exactly in order to manufacture a new pair of wings for the Gull. This information came from Ron Paine, who worked on the Gull at the time, and who clearly recalls that it was only by a stroke of fortune that they could do the work anyway"

If the wing (or wing outer panels) of the Gull had been so effectively destroyed as to render their remains unusable for rebuild or even pattern, it is surprising that a new pair could be built with only reference to the Hendy 302, which were "copied exactly" to reproduce folding wings with flaps, and the very complex lifting flap box?, all features not existing at all on the Hendy 302?

If Flight in 1932 is correct and unchallenged, the Hendy and Gull clearly shared the same or very similar braced spar construction of the Henderson design, but clearly the wings are of differing dimensions resulting in different span, area and cord. If those sections survived on the crashed Gull there would seem to be little need to refer to the Hendy to repair it, if those sections and the wing was really totally destroyed, then all the other unique and significantly different features of the Gull wing (folding flap boxes etc) would have been destroyed also, and could not have been reproduced, even if the complete Hendy Wing was bolted to the Gull fuselage temporarily, let alone copied "exactly" using only the Hendy as a pattern.

I am sure the Hendy wing might provide some good guidance to rebuilding the Gull wing, but it couldnt produce an accurate "Gull" wing without other references, the story seems to have some serious "credibility" gaps to explain, before being accepted as the basis for re-writing history and impuning the "design" or "re-design" claims of Percival?


I wonder if a falling out with Henderson or subsequent concerns of a financial claim arising from the later commercial success of the Gull and the original intention to place the 302 into production, launched Percival into a lifetime of threats of legal defences of his sole design role?, I assume however there is no evidence of him disputing the Flight articles of 1930 and 1932?

I suspect he was rightly proud of his various achievements, and willing to use legal threats when those achievements were challenged without good basis?


Regards

Mark Pilkington

[avion ancien]

Thank you, Mark. It's good to have such input from such well informed people. Yours and that of G-ORDY are better described as essays, rather than posts, on the subject and, as such, have materially enhanced my knowledge and understanding of the inception of the Gull.

[G-ORDY]

Some interesting material there Mark.

On the subject of the lack of wing drawings being available for the Brooklands rebuild that quote came directly from Ron Paine who was one of the engineers involved. He was a very well respected engineer and racing pilot (Miles Hawk Speed Six G-ADGP) and had a very good recollection of the events. He told me this in the early 1980s.

As for your question as to whether the prototype Gull had flaps - the answer is "no". Split, trailing-edge flaps were not fitted to Gulls until 1935, they were of the Schrenk kind and worked by twisting a tube fitted to their leading edges.

At the Press Launch of the re-designed 1935 model Gull Percival stated that the Mew Gull, G-ACND, had been the first British aircraft to be fitted with split flaps (for its first appearance in the King's Cup Air Race in 1934) but they had been screwed shut during the event and a retractable air-brake used instead.

I must say I never considered whether the Hendy 302 had folding wings, I suppose I assumed it had them as virtually all light aircraft of the period had folding wings, but I've never seen a photo of the wings folded nor any drawings of folding mechanism.

[Mark_pilkington]

G-ORDY,

I'm not suggesting there were any drawings at Brooklands, or that the Hendy might not have been useful as a reference, but I am doubting the ability to build a new Gull wing only from reference to the Hendy, when the dimensions (span/cord) and areas (wing/aileron) are clearly different and the structure is clearly not identical, as all shown by the information published by Flight in 1930 and 1932.

I didnt think the Gull prototype had flaps fitted, but the "Gull" Flight article of 1932 certainly confirms it had folding wings and the folding "flap boxes" regardless, as clearly shown in its photos and 3-d Drawing.

I think the Hendy Flight article of 1930 also certainly confirms the Hendy did not / could not have folding wings.

The Flight photos show the Hendy wing outer panel from both root and tip ends.

The root end shows a full end rib extending past the rear spar, as compared to the Gull photo from Belgium that shows the Gull end rib ending at the rear spar.

The Henty outboard trailing edge ribs are also full ribs, with no evidence of a seperate and removable box structure (folding or otherwise), and in anycase a significant and fixed diagonal brace is clearly fitted into the trailing edge, seen in both the photo and 3-D drawing, that does not exist at all in the Gull wing.

It is impossible for the Henty wing to fold back in any way similar to the Gull with that solid trailing edge.

In addition to the dimensional and structural differences, there is a clear rigging difference between the Henty with its straight wing, and the Gull with its dihedral wing outer panels as seen in both photos and the Flight 3-D drawings of both aircraft.

The two wings have many similarities, 13 ribs in the wing outer panel from root to tip, 6 Henderson cross braces between the spars, 5 ribs from the root to the aileron, but they are clearly not identical, the different cord and span dimensions may indicate different rib profiles and rib spacing, the folding feature, missing diagonal, and folding trailing edge might suggest thicker rib materials etc to create a stronger structure? It seems clear the Gull wing is a derivitive or evolution from the Henty design, but certainly not identical so as to allow the Hendy's wing to be copied exactly to create a Gull wing.

But without commenting on Rob Paines respectability, his recollection doesnt seem to fit with the historical and technical facts?, and certainly doesnt counter them?

Regards

Mark Pilkington

[avion ancien]

So - is the upshot of this that:

- Percival was not involved in the "design" of the prototype Gull beyond contributing the idea and some rough sketches;
- the design of the prototype Gull drew heavily upon the Hendy 302 which Henderson alone had designed;
- the "designer" (in the generally accepted meaning of that word in aviation) of the prototype Gull was Bound; and
- the contribution of Lowe-Wylde was limited to providing the facilities for the construction of the prototype Gull?

If so, I wonder why Percival felt it so necessary, for the remainder of his life, to deny those other contributions and assert that he alone was responsible for all the design work required to translate an idea into flying reality? Maybe he was just that sort of man. I've met some like that in my life!

And finally, if you'll forgive a somewhat tangential excursion, I wonder what Jackson said, in the 1960 edition of 'British Civil Aircraft', concerning the design of the Saro-Percival Mailplane? In the 1974 edition he says:

".....the Saro-Percival Mailplane, G-ABLI, designed by E.W.Percival and built under his supervision at Cowes in 1931....." .

It does make one wonder!

[Grumpy1]

I've been following this thread with interest. I found an obituary to Basil B. Henderson in Flight dated 25 November 1955. Although containing at least one error it might fill in a few gaps in the story. http://www.flightglobal.com/pdfarchi...0-%201676.html

Also a letter from E. W. Percival on the Correspondence page of the 9 December issue which gives his version of events. http://www.flightglobal.com/pdfarchi...il%20henderson

The letter from W. E. W. Petter is worth reading.

[Mark_pilkington]

Originally Posted by Grumpy1

I've been following this thread with interest. I found an obituary to Basil B. Henderson in Flight dated 25 November 1955. Although containing at least one error it might fill in a few gaps in the story. http://www.flightglobal.com/pdfarchi...0-%201676.html

Also a letter from E. W. Percival on the Correspondence page of the 9 December issue which gives his version of events. http://www.flightglobal.com/pdfarchi...il%20henderson

The letter from W. E. W. Petter is worth reading.

The Percival letter to Flight in 1955.

I REFER to your obituary notice of Basil B. Henderson on
page 795 of Flight for November 25th. First of all, let me
express my deep regret at hearing of his death. Basil was a friend
of mine of long standing and had my great respect as a highly
trained and most capable engineer.
For the sole purpose of the record, however, one or two
corrections are called for. I was not at any time a member of
Henderson's organization, therefore I did not "join forces with
Henderson and Miles."
The experimental aircraft built in the small shed at Shoreham
with the 40 h.p. A.B.C. engine was not the 302. The 302 was the
aircraft I had built for me by George Parnall at Yate to our design.
It was my personal property from the inception. The contract
to build it for me was made by me directly with Parnall, the
financial responsibility being mine entirely. The specification for
this aircraft was mine, as well as an important share of the design
work. This would be confirmed by an agreement made between
Henderson and myself as to joint ownership of certain features of
the design structure. I later sold my share in these rights.
Basil Henderson was employed by me on the design work and
H. A. Miles (who, I believe, for some years had been with A. V.
Roe as a stressman) on the stressing; Henderson by way of an
agreed lump sum and expenses and Miles by a weekly salary.
These two gentlemen constituted the whole of the Henderson
organization.
Henderson's personal contribution to the design was, of course,
an important factor; he had carried out research work on cantilever
wings, which was a great help.
None other than the prototype of this aircraft was built, but
it was a reasonably successful attempt to introduce the low-wing
cantilever form of aircraft.
These details are perhaps unimportant but the matter has been
incorrectly reported on a previous occasion, and this letter is to
set down the facts.
London, W.I. E. W. PERCIVAL

Regards

Mark Pilkington

[alertken]

AA: Saro-Percival Mailplane, G-ABLI: no entry in 1960.

[avion ancien]

Originally Posted by alertken

AA: Saro-Percival Mailplane, G-ABLI: no entry in 1960.

Thank you. What one hasn't said has no need of retraction or revision!

[longshot]

A few years ago John Hopton sent me these b&w photos of Edgar Percival landing a Gull in Australia (1976) (Joe Drage photographer) and a colour photo of Percival (LH) with John's brother (perhaps ca.1980). Unfortunately I've lost touch with John( computer disasters etc.)

[mike bb]

I'm finding this discussion about Percival designs very interesting. So much design drawing seems to have been done informally, making it hard to trace who did what.

I'm wondering about the early Miles designs - how much help did Fred and Blossom get with early projects like the Satyr and the Hawk to make them practicable?

[Mark_pilkington]

.
I have'nt seen all of the archival records of Percival or Henderson to confirm what claims either has made in detail in personal letters etc, but I feel those are only two people who would know the full details of who actually designed "what".

The arguments "against" Percival are largely derived from:

1. The Hendy 302 is recorded as a Henderson design.
2. The Flight 1930 article supports that position.
3. The Henderson cantilever wing design is utilised in the Gull.
4. The overall General Arrangement of the Hendy 302 and Gull are the same.
5. Percival employed proffessional designers, suggesting he did not design himself.
6. Strong similarities exist between the wing design of the Hendy, and the Gull.


However a reading of the Flight 1930 Hendy article and Percival's letter below can have the two views reconsiled to some degree.

The Percival letter to Flight in 1955.
Quote:
I REFER to your obituary notice of Basil B. Henderson on
page 795 of Flight for November 25th. First of all, let me
express my deep regret at hearing of his death. Basil was a friend
of mine of long standing and had my great respect as a highly
trained and most capable engineer.
For the sole purpose of the record, however, one or two
corrections are called for. I was not at any time a member of
Henderson's organization, therefore I did not "join forces with
Henderson and Miles."
The experimental aircraft built in the small shed at Shoreham
with the 40 h.p. A.B.C. engine was not the 302.

The 302 was the
aircraft I had built for me by George Parnall at Yate to our design.


It was my personal property from the inception. The contract
to build it for me was made by me directly with Parnall, the
financial responsibility being mine entirely.

The specification for
this aircraft was mine, as well as an important share of the design
work. This would be confirmed by an agreement made between
Henderson and myself as to joint ownership of certain features of
the design structure. I later sold my share in these rights.

Basil Henderson was employed by me on the design work and
H. A. Miles (who, I believe, for some years had been with A. V.
Roe as a stressman) on the stressing; Henderson by way of an
agreed lump sum and expenses and Miles by a weekly salary.
These two gentlemen constituted the whole of the Henderson
organization.

Henderson's personal contribution to the design was, of course,
an important factor; he had carried out research work on cantilever
wings, which was a great help.


None other than the prototype of this aircraft was built, but
it was a reasonably successful attempt to introduce the low-wing
cantilever form of aircraft.
These details are perhaps unimportant but the matter has been
incorrectly reported on a previous occasion, and this letter is to
set down the facts.
London, W.I. E. W. PERCIVAL

A clear conclusion from Percival's letter is:

The Hendy 302 was ordered and paid for by him, to an overall design proposed by him but drawn by Henderson and Miles, including further development of the cantilever wing design based on Henderson's earlier work on the "Hobbo".

- The Hendy 302's design was jointly owned by Percival and Henderson and detailed in a contract between them.

- Henderson and Miles were contracted by him to work on the design.

- Percival funded the construction and owned the resultant aircraft.

- The Hendy 302 was a sole prototype.

(Flight 1930 entry for Hendy 302.

The next step in Mr. Henderson's programme was a two-seater
development of the little " Hobo," and
the general " scheme " appealed to Capt.
Percival. The upshot was that he decided
to join forces with Henderson and Miles,
they to do the actual design work, calculations,
etc., and Percival to contribute practical
advice out of his long and varied experience
of aircraft at home and in Australia. A
contract was entered into with George
Parnall of Bristol for the construction of the
machine.

The machine incorporates in its wing construction some unusual and
patented features of which Mr. Henderson is the inventor.

Mr. Henderson and Captain Percival are now arranging for the machine to be built in considerable numbers.

The Flight article confirms the use of the patented spars designed by Henderson, confirms Percivals involvement in its development, the engagement of Henderson and Miles to design work and calculations, and a third party, Parnall, to construct it.

Much argument then derives from the interpretation of who is the designer, the person employed to develop calculations and draw up a design, or the person with the overall vision and specification?.

The similarities and differences of the Hendy wing to the Gull wing are clearly seen in the 1930 Flight photos and other Gull photos shown above, the testimony of Robert Paine that the Hendy 302 was used as a reference to rebuild the damaged Gull only confirms there are similarities (as could be expected), it does'nt resolve who actually designed the entire wing structure.

Without testimony of one of those three involved, Percival, Henderson and Miles, we will never really know how much of the Hendy "design" Percival really did contribute?

I am not aware of correspondence and claims made by Henderson to the arrangements, Percival's design involvement in the Hendy 302, or his own "contribution" into the design of the Gull? - Do his papers exist?


If Percival did hold some contractual and design rights in the Hendy 302, he would consider any wing and other design features extended into the Gull series to be his as well, while acknowledging the design rights of Henderson to the earlier cantilever wing spars used in the Hobo.

Percival died in London in 1984, I dont know what happened to his private papers, and what research might be possible and "confirmed by an agreement made between Henderson and myself as to joint ownership of certain features of the design structure."

Of course that is unlikely to prove who said and did what in the design room on any given day, during the development of the Hendy 302, or the later Gull, and the debate will rage on.

However its unfair on inuendo alone to then question or dispute Percival's claim to the design of Saro-Percival mailplane, without any evidence other's are laying claim to the design work when Saro acknowledge his employment/involvement?

Speculation is not a subsitute for research, to justify revision of history.

regards

Mark Pilkington

[avion ancien]

[quote=Mark_pilkington;1505839].

However its unfair on inuendo alone to then question or dispute Percival's claim to the design of Saro-Percival mailplane, without any evidence other's are laying claim to the design work when Saro acknowledge his employment/involvement?

/QUOTE]

I apologise if I have created the wrong impression. I did not question or dispute Percival's design of the Saro-Percival Mailplane. I do not have any evidential basis upon which to do so. However it is my opinion, based upon that which I have read, that Percival's claims to be the sole designer of the Gull are not supportable. Thus, perhaps in jest, I invited comment upon the design credentials of the Saro-Percival Mailplane. Nothing has been forthcoming to contradict that which I have read, on this subject, thus far.

[John Aeroclub]

A facinating thread and very much in my prime interest area. Would any one know if the colours of the 302 have been recorded anywhere?.

John

[avion ancien]

I presume that there is nothing extant concerning the Hendy 311, the reputed design for a three seat version of the Hendy 302, about which Don L. Brown is reported to have spoken post WW2?

[longshot]

Originally Posted by JDK

.

I have some vague recollection of reading a reasonably detailed account of the saga. It was either in an issue of the modern Aeroplane magazine, or the National Museum of Australia's website. But beyond that, I really don't recall.

HTH!

Did Richard Riding write A J Jacksons's obituary in Aeroplane monthly?...it might mention the Percival wrangle

[JDK]

Originally Posted by longshot

A few years ago John Hopton sent me these b&w photos of Edgar Percival landing a Gull in Australia (1976) (Joe Drage photographer) and a colour photo of Percival (LH) with John's brother (perhaps ca.1980). Unfortunately I've lost touch with John( computer disasters etc.)

Lovely stuff, Longshot. Drop me a PM with your details, and I can pass them onto someone who is in touch with John H.

[Mark_pilkington]

Originally Posted by JDK

Lovely stuff, Longshot. Drop me a PM with your details, and I can pass them onto someone who is in touch with John H.

longshot, PM sent with John's email contact details

Regards

Mark Pilkington

[longshot]

Thanks, Mark, got that...

JDK, Thanks, it's a 'longshot' about fhe AJJ obit, but they must have poblished something...

Seasons Greetings, all....Mick

[G-ORDY]

Originally Posted by longshot

Thanks, Mark, got that...

JDK, Thanks, it's a 'longshot' about fhe AJJ obit, but they must have poblished something...

Seasons Greetings, all....Mick

I wrote the obit for AJJ in "Vintage Aircraft" magazine and I didn't mention Percival. For Percival's obit I dedicated an entire issue to him. (VA # 30)