KLM DC-4/C-54 (Papertrade 1:50)

[scon10]

The ventral fin with a rounded top, that's a nice detail.

[Diderick A. den Bakker]

Originally Posted by scon10

The ventral fin with a rounded top, that's a nice detail.

I don't think you could describe this as a fin. It is more of a shock absorber in case of a too enthusiastic starting climb. But more importantly, there is probably a sort of cavity inside which takes a support necessary when the plane is being loaded, to prevent it from tipping downwards as long as the weight inside has not been properly balanced. Plenty of pictures on the web!

[romanmodels]

Nice work Erik

[Isaac]

Originally Posted by Diderick A. den Bakker

I don't think you could describe this as a fin. It is more of a shock absorber in case of a too enthusiastic starting climb. But more importantly, there is probably a sort of cavity inside which takes a support necessary when the plane is being loaded, to prevent it from tipping downwards as long as the weight inside has not been properly balanced. Plenty of pictures on the web!

Correct, it is not a fin. It is only a fairing over the structural segment that support the anti tilt pole / strut



Isaac

[yankeekilo]

Originally Posted by Isaac

Correct, it is not a fin. It is only a fairing over the structural segment that support the anti tilt pole / strut



Isaac

the function of the tail skid is to assists in case the pilot over-rotates the airplane during take off or landing, the tail support is a secondary use to that...

[Isaac]

Yes, it was a duel purpose feature.


Isaac

[scon10]

The ventral fin is a part of the vertical fin. It stretches out over the top of the fuselage and serves to avoid flow separation at low speeds and high angle of attack, such as during landing. If you look at the Fokker F-27, you see it has a large ventral fin, stretching from the underside of the de-icer boot all the way to the trailing edge of the wing. The Douglas DC-4/7C has a realtively small ventral fin, nicely streamlined into the main vertical fin.
Most models make that as a left and a right part, glued at the top, so it has normally a sharp edge on the top. I commented on the nice rounded shape this model has, which is unique.
What Diderick through Yankeekilo are referring to, is the tail bumber at the underside of the fuselage.
I hope this makes sense.

[Isaac]

Originally Posted by scon10

The ventral fin is a part of the vertical fin. It stretches out over the top of the fuselage and serves to avoid flow separation at low speeds and high angle of attack, such as during landing. If you look at the Fokker F-27, you see it has a large ventral fin, stretching from the underside of the de-icer boot all the way to the trailing edge of the wing. The Douglas DC-4/7C has a realtively small ventral fin, nicely streamlined into the main vertical fin.
Most models make that as a left and a right part, glued at the top, so it has normally a sharp edge on the top. I commented on the nice rounded shape this model has, which is unique.
What Diderick through Yankeekilo are referring to, is the tail bumber at the underside of the fuselage.
I hope this makes sense.

Scon10

OK, I see where the confusion is at.

You were commenting on the vertical fin extension forward ( on top of the rear fuselage ). Got it now. It is called a Dorsal fin.



The fin on top of the fuselage is called the dorsal fin. The fin below the fuselage is called the ventral fin. You used the term Ventral and that is where we looked at the bottom and there is no fin there.


Here is a picture of where the fins are located on any aircraft.





Isaac

[scon10]

Sorry, you're right, my confusion.
Still a nice detail

[Erik Zwaan]

During my PPL-course we always used the wording horizontal and vertical stabilizer, rudder and elevator but apparently there are different words to describe the same surfaces.

The design of the model caters for a central tube that runs along the entire fuselage and which aids in structural strength. When dry-fitting the empennage with the aft fuselage sections and the central fuselage/cockpit I noticed a slight difference in the circumference of both mating ends, making it difficult to join neatly. I do not know where this offset came from, either from the model or from inaccuracies during the build, but it required me to be able to properly press the joint from the inside to have a neat joint. That requires space and for this reason I turned the central tube into a kind of telescope tube and did not install the right freight door yet. Also, the former that is somewhere halfway the still open door was going to be put in its place later on.

Quite an elaborate procedure but it worked. The fuselage joint turned out ok and after extending the telescope tube (with glue on the end cover) until it came to rest on the aft fuselage former and sealing of the inner/outer tube with glue after the extension, the door could be glued in place.

Also a few small vent inlet or outlets on the skin and the remaining part of the dorsal fin. As an option, the hinges of the doors can be detailed. And this basically concludes the fuselage construction. As you can see from the pictures it is a big model, by seizing against the items on my desk.

Next will be the wings; with the flaps and ailerons for a bit of a relaxed start . At least, so I hope.

Cheers,
Erik