Hurel-Dubois HD34 1950's A/C with high aspect ratio wing

[dcoquelet]

I plan to design & build the HD34 Hurel-Dubois A/C (see link hereafter)
https://en.wikipedia.org/wiki/Hurel-Dubois_HD.31
Oldprops Hurel Dubois HD34

Actually you can see a tentative for the wing which has a high aspect ratio wing with narrow chord and was produced in France in the 1950s
it is suprising to see that new future A/C are going to come back to this high aspect ratio wing.; see boeing future project :
Boeing Feature Story: Envisioning tomorrow's aircraft

I am not so speed as scissorsandplanes in designing as i do it manually W/O specific 3D to 2D tool usind AI software for repaint livery.. i will do it in the IGN (F-AZNH) livery for the "Bicentenaire de la Révolution Française"
So it will be long to come but thanks to the long winter nights, i hope to have finish it before end ot this year.
May be in the future i'll learn to use SketchUp, however i like this pragmatic step by step approach in designing parts manually
cheers - Didier

[scissorsandplanes]

Hi Didier,

To be honest I never heard about this plane before. The design indeed can be interesting.
In what scale are you building the model?
I see you found a good 3-view drawing. That's always a good start. I Also start from there. the rest is part math, part experience, part trial and error.

By the way, I only use Excel and Word for my designs.

Good luck with the design.

S&P

[dcoquelet]

For S&P usually i use 1:100 scale but in fact the scale is not really an issue when using vectored pictures features, but in this particular case the wing span 45m is such that the model will have 45cm wing span, so i plan to use firstly about 1:200 scale..; we will see after for 1:100 scale

For those who may be interested in more information about the Hurel-Dubois Saga and why i wish to design such a plane: this compagny , after the HD plane (HD45) frustating competion against the Caravelle from SNCASE ( Sud-Aviation then Areospatiale and finally Airbus), try a tentative with Fred MILES from Great Britain and the joined party aimed to develop a STOL A/C which ended by the SHORT "Skyvan"
Short SC.7 Skyvan - Wikipedia, the free encyclopedia

Then the compagny became a sub-contractor for mainly Dassault & Aerospatial, Socata..to built Aero-Structures...in the early 80s they launch 2 activities: design and manufacturing of Thrust Reverser and Composite material structures.. So when i enter this compagny in 1982 as a young stress engineer i start to stress validated the design of Falcon 900 thrust reverser & the 4 pivoting door of the A320 Thrust Reverser.. In 2006 the compagny enter the snecma World and is now part of Safran Group under the name of Aircelle

[scon10]

It is an intresting aircraft, the HD-34 and its derivatives. The reason for its design was, that theoretically, you get the maximum lift and the minimum drag the higher the aspect ratio (span over chord) is. The problem however is that it is difficult to get sufficient strength in the wing. So you see in the HD-34 the use of wing struts, needed for strenghth, but at the cost of extra drag. The F-27 reached a fairly high aspect ration in a cantilever wing with the metal bonding process and now the carbon fibre wings of modern jets also reach higher a.r. and therefore better economics.
So this model is going to be a tribute! I look forward to your design.

[dcoquelet]

Thanks Scon10 for your post, I'll try my best for the design.. i'm not in a hurry so it should take time.. As you said it a tribute for me and to promote this type of A/C.. i think if the design is acceptable and good enough i will surely propose it for free download.
Didier

[dcoquelet]

That's it.. due to some bad weather here in Europe i left outside home work & i' am coming back on the design of this Aircraft.. Already i must admit i 've to optimize central fuselage sections & end formers such as they fit better together and to be more representative of the cross section.; i need to draw the fuselage aft part, tail and horizontal plan
Then the Wing/Fuselage connection fairing.
In the attached pictures you can see the beta existing cutted out parts, Wing spar & ribs squeleton.
Coming later to show improved parts.

[PICARDIE]

Hi dcoq,
FYI, there is a HD (may be it is F-AZNH) on display at Creil flight club. As a matter of fact, the word "display" is not really appropriate since this plane seems to be abandoned, waiting the point it is so deteriorated it will be just good for scraping. It was likely left on that place because IGN (Institut Geographique National - for the members outside of France ), was (is still?) based at Creil AFB and was a user of such planes for taking pictures of the ground at high altitude to create maps at the time the RECO satellites did not exist. Considering where you are living, Creil is not too far from your home and a visit to the Creil's HD might be worth if you are looking for details.

[dcoquelet]

Thank's a lot Picadie for the advice.. I am aware of this HD plane at Creil location
Could be may be helpfull..and thanks for the history..
Just to let you know that i am an engineering employee of this old society Hurel-Dubois until 2000 when sold to the Snecma..now called Aircelle in 2005

[Karl]

Its quite a few years ago now (maybe 12-13) but I travelled to an airfield to the south of Paris where a large number of old aircraft were stored including an airworthy HD.

If I remember correctly there was a Sturmovik, a Corsair and a number of other aircraft.

I was there to view and purchase a collection of Gloster Meteor spares.

The hangar had been used by the Germans and was quite large.

Maybe I should search google maps and try to remember where it was.

[dcoquelet]

Karl, was there a grass RWY..? small plateform or big one ? i can see 2 potential airfield
1/ may be you are talking of La Ferté Alais - (LFFQ) - 4° 29' 58"N / 002° 19' 48"E 2km NNW of the Town La Ferté Alais (Dept 91 - Essonne) - where stays the Jean Baptiste Salis association to promote the french aeronautical heritage..?
2/ Or alternatively, may be the HD34 stored in the Aeronautical Museum at Melun-Villaroche airfield (LFPM) 48° 36' 19" N / 002° 40' 15" E near the SNECMA (CFM engine) factory..