In Aero France, January 1956 issue, I found an article with the title " L'Avion A Ailes Propulsives Et A Gouvernes
Par Controle De La Couche Limite", including a 3-view.
I've attached the text, too, maybe a native French speaker could give a short summary ?
I think, the 3-view shows the DA 8, obviously an 8-seater, but mentioned, too, is the DH G 4,
an experimantal two-seater, which seems to have been build.
The goal is to produce small, low-power transport aircraft: max 750 hp, moderate commercial speed 350 km/h, capable of flying at low speed: 50 km/h, of taking off without assistance from small and bad strips.
Fuel use per kg of thrust is: stopped 0.37 kg/kg/h , at 385km/h 0.7 kg/kg/h.
Here are the reasons which lead René Dorand to use low pressure fluid:
The feeding of propulsive wings by medium-pressure fluid (ratio 1.5 to 1.7) is interesting for planes with a slim profile, for which the cruise speed is around 700 km/h, with a minimum speed of 90 km/h.
The comparison with classical airplanes enables the following observations:
- for the same performance, the rolling length is divided by 4
- in the same flying conditions, horizontal speed is increased by 30%
As an example, the performance of a twin-seater trainer Fouga Magister fitted with medium-pressure propulsive wings would be as follows:
The experimental twin-seater Dorand DH G4 is considered with a Turbomeca Soulor powerplant.
With a feed by low-pressure fluid (preferably mixed fluid, pressure ratio 1.06 to 1.15), the minimum speed is divided by 2, the rolling length divided by 5.