Carbon fiber Pfalz D.IIIa fuselage?

[berman]

I was just wondering how practical it would be for someone(not me) to mold German streamline fuselages in carbon fiber composite such as the Pfalz D.IIIa, Roland C.II, and Albatros D.Va(painted fuselage versions). The bulkheads would also be molded carbon fiber/epoxy except for natural finish wood bulkheads in the cockpit area. The natural varnished plywood cockpit interior surfaces of the Albatros would be covered with a thin veneer. Wings and tail surfaces, conventional construction.
Another thought. Modern gas engines are higher revving with lower torque so they can not swing the original large WWI props. Scale model airplanes use diesel engines for scale size propellers. Although it would not sound right, could a fullsize replica use a diesel engine?

[RAF56_Ball]

How practical? Financially sounds very expensive. Technically interesting, though.

Deisel engines may be too heavy, and temperatures may badly affect fuel, from what I have seen on other forum threads.

[berman]

Molded carbon fiber fuselages would only be practical if some company offered a complete aircraft kit. First you need to make the male fuselage plug and then make thick fiberglass molds with external steel stiffeners to prevent the molds from distorting. However, construction for the builder would be greatly simplified as the entire fuselage could be made in two bilateral halves.
The big question is could enough kits be sold to offset the tooling expenses?

[womenfly2]

The late Frank Rider had a 7/8 scale Albatross I believe built by a Joe P .. something, sorry cannot remeber his last name, with a fiberglass fuselage shell and steel tube frame. Power was a inline 6 Ford engine I think. Frank was going to kit it.

Should be somewhere on the forum, do a search maybe.

I would build a steel tube fuselage with a plywood shell overlay. Keep it simple.

[hank jarrett]

Frank's Alb is in Virginia Beach VA at the Military Aviation Museum. Really nice looking aircraft. They are getting a nice collection of WW-I planes there now and have even built a new hangar for them.
Museum | Fighter Factory
Hank

[jumpinjan]

Hank is correct. I have traced it back to it's orgin and actually talked to the builder. The fuselage is based on a wooden box structure (very similar to the 7/8 SE5s), then covered with foam blocks & shaped, and then a layer of glass cloth & resin. A solid fiberglass (or carbon fiber) shell will be way too heavy and probably not stiff enough if thinned out. The real way to do this is with a wooden core (cedar or balsa) made up with wooden strips, and then covered with a light weight glass or carbon cloth & resin.
Jan

[berman]

I think that a carbon fiber shell would be equal in weight to the original plywood sheeting used on the original aircraft. Proper vacuum bagging molding would assure the correct ratio of epoxy resin to carbon fiber cloth to obtain maximum strength at minimum weight. Of course, carbon fiber bulkheads would be needed just like the original aircraft required bulkheads for strength and stiffness.
Compare the weight of old wooden tennis rackets to modern carbon fiber versions. A carbon fiber fuselage would weigh the same or maybe less than the original all wood fuselage. The male plug, for the fiberglass molds, could be made from a plywood core with shaped foam blocks.
Other modern technology could also be applied to a kit such as abrasive waterjet cut wooden ribs and other wood components plus laser cut metal fittings.

[sheppo]

If you are prepared to go to the trouble of creating a full size mould, bulkhead supports, longeron replacements et al....then why bother going for a carbon fiber replacement? Why not use wood as per the original and avoid reinventing the wheel....Is this for a scale copy?

[Maxim08]

I agree with Sheppo.
The originals had a frame of bulkheads and longerons covered with pre molded plywood shells. Note that this is plywood in the dehavilland mold (pun, ha ha) made with strips of veneer laid in differing directions. This process shows clearly in the factory Pfalz films.
While Pfalz used female molds, you could go the Mosquito way using male molds from concrete or whatever.
Regards
John

[sheppo]

I would be quite concerned about the attachment points for engine bearers, wings and struts etc. The internal structure you (i assume) are trying to replicate is somewhat different to a conventional modern aircraft. If you are attempting to make the interior look similar at least in the cockpit areas, how would you achieve the appearance of interior ply (or strip layups) , longerons etc while maintaining the necessary fillets required by glass/fibre construction?
Carbon fibre is an alternative to ply that would require significant re-engineering of a very functional construction method, the weight difference as stated by Jan will likely be negligable at best, the cost would very probably be somewhat higher as you would need many of the more expensive timber working tools just to create the molds and frames etc in the first place and then add to this the vacumn systems etc
Using a secondary layer over ply can (structurally speaking) also be pretty redundant depending on the design. The fail/weak points of the original structure still exist, albeit now hidden by an outer coat/surface, and the dissimilar properties of the ply and secondary layer open other possibilities for structural issues.

Me personally, I'd hate the idea of buggering around fitting ply frames etc inside a molded skin only to end up with a featureless smooth exterior. No nail lines, no scarf joints, no bulges or ripples, drips of varnish, bloodstains (mine), etc...really, its all the interesting aspects of a ww1 plane gone...