waikong - I think they're the same concept as the aeronautical flying wires used by the Pup and many other British aircraft. Think this is a bigger implementation, as the Pup still used double wires coming from the upper wing struts.
I eyed that set (RB Model makes them, no?) when I was prepping for the Pup, but cut-to-length on something like that gives me the willies!
As for EZ Line, I've got some. Didn't know it sat flat, but then I haven't taken it out of the little bag it came in, either.
Heavens Eagle - I think there may be a double turnbuckle (or some kind of wider, flatter thing) going on, but I can't find a single angle of an actual WWI N.28 showing those upper strut-to-fuse wires as doubles.
This one's like the one above, only at greater resolution.
![](http://www.airminded.net/n28/LLK27.jpg)
Here's the prototype (if you look closely you can make out the Eiffel Tower above the cowl).
![](http://www.airminded.net/n28/N28_4434_9oc.jpg)
A Swiss example. Looks like the forward wire is actually a bit slack in this one.
![](http://www.airminded.net/n28/N28_N6212c.jpg)
This one would make a great diorama:
![](http://www.airminded.net/n28/N28_taxi.jpg)
Post-war courier service, but same idea:
![](http://www.airminded.net/n28/N28_CGT.jpg)
Far bottom left. There's clearly only the one eyebolt and what looks like one turnbuckle.
![](http://www.airminded.net/n28/Cockpit3.jpg)
This is apparently from the national museum of the USAF, and confuses the heck out of me. I need to do more research into this particular aircraft and whether it's a replica or not.
![](http://svsm.org/albums/Nieuport28usaf/DSC09044.jpg)
![](http://www.buscinfo.com/EZ-PhotoAlbum/Album09_WWIAcft/nieuport_28.jpg)
![](http://farm4.static.flickr.com/3164/2874498424_01b23d8c24_b.jpg)
On the Bench: 1/32 Trumpeter P-47 | 1/32 Hasegawa Bf 109G | 1/144 Eduard MiG-21MF x2
On Deck: 1/350 HMS Dreadnought
Blog/Completed Builds: doogsmodels.com