Breguet AG-4, September, 1914, Scratch-Build In 1/72 (W.I.P.)

This machine was pretty much a one-off, only two ever being constructed. M. Breguet flew his prototype AG-4 to the Entrenched Camp of Paris to join a motely collection of aeroplanes available there at the end of August, 1914. On the 2nd of September, he made a reconnaissance flight with Lt. Watteau as observer, during which the first signs of the German general von Kluck's turning the extreme right of the German forces to pass to the east of Paris were detected. This was the germ from which the subsequent riposte of the First Battle of the Marne would come, which makes this one of the most significant aerial missions of history, and gives the AG.4, wretched a flying machine as it was, an important place in aviation history.



I will be doing this machine as it appeared (or as I think it appeared, anyway) during its historic flight, with the tail surfaces shown in the photograph above (they were later altered), but without the service markings (the machine was still M. Breguet's property when that flight was made).

Here are the wings...



Here, the full suit of ribs have been sanded in.



Here, the scallops of the trailing edges have been put in.



Here the rib tapes are on the upper wing (only every third rib was taped), and the whole sprayed with primer.



Here is the lower wing, split into separate panels joined by bare spar (the front from paper-clip wire), with tapes on, and sprayed with primer.


The AG-4 used the 160hp Gnome twin-row rotary. I am using the twin-row Oberursel from an ICM Pfalz E-IV kit. This fits the cowling in the kit very well, but that is awfully thick, so I extended the length of the cylinders by adding caps of 1mm sheet, and trimmed off the lifter riods moulded to the front of each cylinder. The crankcase front of the kit piece is flat, so I gave it a bit of a dome from 2.5mm tube. To the cylinder heads, I added lifters from .5mm x .25mm strip, and put in lifter rods from .25mm round rod. Here is the result, greatly magnified, after a coat of primer.



The forward part of the AG-4 fuselage was armored, its rearward portion was of standard construction. I have made the fuselage in two sections....



Since the Pfalz cowl matched the drawing dimensions, I have used it as a sort of gauge for the front plate here.



Here the bottom is assembled to the upper frame.



Here is the rear portion's lower part, together with the forward piece.



I put a 'cap' on the front of the rear piece, to provide a rear to the cockpit area and give something to grip at that point when working the assembly later, and to ease some oddities of their juncture.





Once these were were glued together, I rounded the cap to a proper shape, and laid in the turtle-back, from a piece of 3mm sheet (a thin wedge of scrap left from making the wings of a Hawker Demon late last year), and bit of 1.5mm sheet. The 3mm piece was sanded to a slat first, then the 1.5mm piece was put on, and sanded down to final slant. Then the proper contour was put in.

I expect the next step will be doing the interior.