I built this WWI Airco DH2 to fly in the Dawn Patrol Games (CCRCC) profile combat competition. Hope to fly it tomorrow. I couldn't use the stock muffler because I didn't leave enough room between the engine and the bottom wing. I wanted to fly it today but there was too much wind. These planes are great fun to fly and to build.



Jeff

Way cool, were having to much fun!!!!

I gotta admit, that's the best looking WWI model I've ever seen. Got plans?

Dave: I picked up the other "Kit". Hmmm... what to build...

Thanks Matt.

No Plans. I used the same basic plan form as the other Rick Foch plans and built it one decision at a time. I wouldn't mind putting together plans for it but I don't have CAD software. Here are a few things I would do differently:

1. I stretched the nose 1 1/2" because the engine is behind the CG and I knew I would have to add weight. I ended up adding 11 oz bringing it up to 4 lb 3 oz. Pretty heavy considering most of the other build out to about 3 lbs 6 oz. I would streach the nose another inch. I don't think it would look too "wrong" and it would probably let me loose one or two ounces.

2. THe stock muffler didn't fit. It hit the bottom wing. I would turn the engine the other way to take advantage of the greater clearance from the engine to the upper wing. I could just flip it over but I recessed the mounting rails and it would look strange. It would also make the carb needle difficult to get to.

3. I though of using pull pull on the tail surfaces to reduce weight but, because of the need to rout the wires around the propeller, it was getting complicated. I might retrofit this. It would probably save me another two ounces of lead in the nose.

THe major difference between this and Rick's other planes of course is the pusher configuration and the fuselage framework that supports it. Here is a description of how I handled it:

In order to minimize the effect of the aft mounted engine on the CG, I recessed the trailing edge of the wings about 2" which is probably an inch more than scale. I added a rear spar to support the tail booms and installed the booms as follows:

1. I cut pieces of webbing for the wing bay that houses the booms out of 1/8" ply and made it about 1 1/2" long, plenty of room to slide them sideways for fitting.

2. Upper wing: In the front webbing, I drilled a hole to accept the carbon fiber boom near the top of the webbing and in the rear webbing I drilled a hole in the center. (The upper booms slant down a few degrees toward the tail. The lower ones slant upward significantly) Lower wing: Drill the front web at the bottom and the rear at the top so the boom pretty much touches the bottom spar in front and the top spar in the rear.

3. I dry fit the booms over the plan (I drew the key elements over one of Rick's Spad VII plans) and mitered the booms to fit together at the tail. It required some filing of the holes and filing a grove in the trailing edge of the wings for each boom. Finally, you need to add balsa around the booms where they pass through the covering so you can iron it down.

4. Set the booms aside until the model is covered and put together. When covering, leave an opening in the bottom wing to access the attachment points for the booms. In the top wing, I did it through the servo hatches.

5. use 30 minute epoxy to glue in the booms in the bottom wing. You need time to work. Glue and clamp the tail end of the booms together at the same time. Slip fit the top booms into place to make sure of alignment while gluing the bottom ones into place. When the glue sets, glue in the top ones. I used micro balloons to give the epoxy more substance. It is crucial to get the upper and lower booms perfectly aligned as they determine the alignment of the rudder and elevator.

This is probably not all that useful without plans.

I will try to at least make some drawings and detailed instructions so that anyone that picks up a set of Rick's plans will be able to use them to build the DH-2. It is not an easy build but it sure was fun. I still have not flown it. THe wind died down yesterday evening but I didn't finish redoing the fule tank until too late to fly.

Just for kicks, here is a postumous picture of my Spad VII that died a cruel death in front of a large crowd at the PGRC warbird rally. Still don't know for sure why it went down. It was way out of trim and it took a couple of minutes to dial it in. After another minute of flying ovals it kicked hard to the left and dove in without responding to controls. I can rebuild it but only the fulelage survived mostly intact. The wings are no more.

Well, I finally rebuilt the SPAD. Made it better than it was. It is about two ounces lighter (Took out all the extra wing bracing that I thought it needed. It also has perfectly straight wings with about 1 degree negative incedence in the upper wing (the original wings had so much twist that even after applying heat and weight every night for a week you could still see it from a distance. It was a bear to fly. Should be much improved now. Waiting for flying weather.

Since the Dawn Patrol Games also use bombers, I am building one of those too (Caproni Ca.42). Here it is so far. Need two more wings, tail feathers and a center pod wor the pusher engine. I am planning to use 3 Saito 30s. I heard the other day that the Dawn Patrol Games are scheduled for early April. I'll be ready!