Persistance pays off.

[Deskpilot]

Some time in the past I mentioned the Citroen GSA boxer engine and wondered if it would be suitable for an aircraft. I found that there was indeed, one example where it had been used but couldn't find any info on the plane,, namely the AS-37, designed by a Frenchman named Andre Starck. Well, yesterday I struck gold. I went to a French aviation site and found, not only pictures of the plane, but also a new and intriguing design configuration that is not used today, at least not in this way. It employs what is known as the Knoller-Belz Effect. That is, a constant, wide open slot, between 2, staggered wings that are boxed at the ends. This produces a very wide c.g. travel range which gives STOL and almost stall proof performance. The nearest I can equate today would be the Flying Flea(not Boxed) or maybe the Sunny Boxwing. Both these designs have the close coupled wing set-up.

 

Rather than go into my own interpretation, I'll leave it to you to peruse the following link. For what it's worth, the Citroen engine was a little under powered for such a large aircraft at 65hp so Starck eventually opted for a 100hp Porche engine. This doesn't rule out the use of the Citroen, although it will need a PSU to reduce the 8000rpm the engine is capable off.

 

4cyl; Citroën GS 1.2; 65hp@5700rpm; 1973-1983; Wt = 220#.

 

Geared to 0.5 and adapted to drive two pusher propellers; this was one of the engines developed for the Citroën GS automobiles; other GS engines of the same configuration had 61.9 cu. in. / 1015 cc, 68.9 / 1129, 79.3 / 1299, and 121.4 / 1990 displacements. Starck, too, found that his aircraft was underpowered with this engine and turned to a converted Porsche engine of 100hp.

 

J78-79toJ82-83; SA7/75, 8/76.

 

Applications: (France) Starck A.S. 37A [F-WYBQ], A.S. 37B [F-WXDU].

 

http://www.citroenet.org.uk/passenger-cars/michelin/gs/flat-4/engine.html

 

http://www.rexresearch.com/starck/starck.htm

 

The 1st images are of the later, modified plane. Scroll down for the original AS-37.

 

 

[Deskpilot]

What...no comments. Surely the configuration deserves some discussion if nothing else.

 

 

[shags_j]

Hey it looks really interesting. I need to read up on it more though (I think I my do an RC airplane with this config and see how it goes).

 

Should probably leave the schwastika off yours though ;)

 

 

[fly_tornado]

What...no comments. Surely the configuration deserves some discussion if nothing else.

It is old and french, good if its a bottle of wine but not an engine. Where do you find parts for a 40 y/o engine?