Now for a little planning. For the engine I think I'll be using either a Saito 56 or possible the 62 which is the same in all dimensions but a few grams heavier and provides a bit more umph (0.1 hp more). Cost is the same. Both fit under the cowl with a couple millimeters to spare.

With that decision made I can start thinking about how the engine can be mounted and how I need to build the recessed firewall. I could mount the engine upright and still have it fit within the cowl. But then I'd have to install a glow plug extension (and make sure there's access to get at a burned out plug). This would be the cleanest installation from a scale perspective. I could also mount it inverted which would give easy access to the plug, though I might have to "destroy" the area between the UC legs. Finally, I could mount it at an angle (90 left or right, -45 left or right). I need to think about the pros and cons of each of these options.

I also need to think about the reinforcing selected areas of the fuselage. The bamboo frame will be plenty rigid in the rear with the cross rigging but there's no rigging in the front and need that to be rock solid too. I also need to think about the attachment points for the UC and cabane struts. I could go with the standard slotted beam at all four locations. But I'd like to explore the idea of a scale mounting method that doesn't involve the standard bent music wire technique.

Another issue is that I plan to build the wings around a one-piece full length spar as per the original. I may even experiment with a scale size box spar. On the DrI, the bottom wing spar was attached in the slot in the frame (which is larger to accommodate the mounting brackets on the front and rear of the spar) and then the slot is covered over with an aluminum panel. The middle wing is also one piece and essentially laid on top of the fuse top longerons. After being bolted to the longerons, the cabane struts are attached, the top fairing is added and then the guns mounted. Finally, the top wing is bolted to the cabane struts.

I think I should have a look back through Del's GT DrI thread.

Last (for now), I'm probably start working on a "first version" of the rudder and/or stab+elevator tomorrow. I'll be using a combination of 3mm dowel, 3mm aluminum tube, 5 or 4mm square hardwood stock and some 2mm balsa strips. I'm going for the lightest possible version that is still 100% scale in outlines and structure. The plan at the moment for the first version is to use the 3mm aluminum tube to form the outline of the elevator, 4mm dowel for the elevator leading edge and 5mm hardwood for the stab trailing edge, which will give me something to screw/bolt the scale strap hinges onto. The LE on the stab will be 3mm dowel and the internal "spar" will be 4 or 5mm dowel. The ribs will be from balsa and be shaped after construction.

Material facts (weight per 10cm):

5x5mm hardwood (Japanese cypress): 1g
4x4mm hardwood (Japanese cypress): 0.6g

4mm aluminum tube: 1.5g
3mm aluminum tube: 1g

3mm hardwood dowel: 0.33g
3mm bamboo dowel: Just a bit more.



The final photo is a reminder of what a running LeRhone (Oberursel II) looks like.