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Jovi’s DC-3 Build Project: Chapter 3, Building the Wing

By Jovi Murek

Hello again, well I’m back at it and building up the DC-3 Wing for this chapter. In this step, we will build up the center section of the wing. This aircraft was designed for nitro engines and, as you know, I am going to convert to electric.

Building the center section required a few modifications needed to be done first. W3 rips required cut out for the retracts, Firewalls got completed with the blind nuts installed. Other changes were needed, but just not now. So, I laid out the Center Spar and glued on the Ply Center Spar together once it cured. Next was to test fit the four plywood ribs and fit it to the building plans. From here I fitted the remaining ribs and fitted the wing mount block and the blocks for the retracts. Next was to fit the TE, (Trailing Edge). In the next few photos, you can see how it was all done.


Now that it all fit correctly and was flat on the building board, I was ready to glue, however, now that I see how it fits, I took it all apart and was ready to modify the main spar to except the retracts. Close to the outer ends of the main spar, I had to remove a section of the spar on both sides. This allowed the mechanics of the retracts to fit. The Top and Bottom spruce spar would be the strength to hold the cut-out section of the main spar. Alone with two strips of 1/16 plywood attached to the spar over the area of the modification to the spar.

DC-3 Fact:
The DC-3 was not only larger than the DC-2, but also much easier and safer to fly. An automatic pilot was installed as standard equipment. The overall design of the DC-3 was so successful that its basic specifications were never changed. Once the first DC-3’s entered service, the speed at which the entire industry converted over was limited only by the rate at which Douglas could produce them.

It was time to put it all back together and test fit all the pieces to make up the center section of the wing. Once I looked it over, and everything was just perfect, I started to glue the parts together with CA glue. Let it sit for a while, (just to make sure) I then added the TE and added some rails to the wing. I also added the dowel pins in place, motor mounts for the retracts. Ok, center section was coming together, as shown:

Building the outer panels.

As I laid out the parts and modified the spar, I pined everything down to the building board. The parts
are designed so the wash-out is automatically built in. A lot of pins were used to make sure that the structure was straight and flat on the building surface. As you can see the outer panels were easy to assemble. Shown in the following pictures.

Now it was time to take the right panel off the plans and do a quick fit to see how the right outer panel fits with the center section of the wing. Looking good so far!!

As quickly as the right panel went together, so did the left panel go together.  Now it was time to combine all three sections into one and then I have my wing.

I had to be extremely careful with the wing at this point. Trailing edge on the ribs for the flaps could have gotten broken off. Now it was time to work mounting the engine Nacelles as shown.

Now we have both done.

She is starting to look like a DC-3 wing.
DC-3 Fact:
Among many things that made the DC-3 so successful were its ability to survive potentially catastrophic circumstances, its load carrying ability, and its longevity. The DC-3 was the first aircraft that could generate revenue for its operators just by hauling passengers! The DC-3 was the right plane that came along at the right time.
Mounting the Retracts

At the time this kit was designed, they were no electrical retracts, only air. Today we do have electrical retracts and this will make the installation much easier than air. At the same time, I started to make up the skins for the bottom of the wing.  Yes it was time to start sheeting the wing.  As you can see in the pictures below, I made all the skin for the wing.


Did the outer panels first, laid them out to see how well the skin would fit. Ok let’s put those off to the side and let’s get the underneath of the wing. Here is a picture of the bottom getting skinned and the retracts are mounted in position.

Now let’s get the outer panels skins in place. Here I started with aft section of the wing got it placed into position and let it cure.
Then I did the other side aft section and let it cure. The next day I did the
forward section of the wing and before I knew it, the bottom of the wing was covered. There were a few things I had to do inside the wing before I was able to start sheeting the top of the wing, like gussets were put into place, hinge blocks and putting servo wire in the wing.
DC-3 Fact:
The 2,000 th C-47 Skytrain rolled out of the Long Beach, California plant on October 2, 1943. Determined to make this occasion a spectacular on, Joe Messick, the Public Relations Manager for Douglas, decided it would be good publicity and boost employee morale if he were to autograph the fuselage for everyone to see. By the end of the day, hundreds of production workers had done the same. Though the chalk signatures and messages were rubbed off before the Army Air Force would accept the plane, many
names, addresses, and messages left by “Rosie Riveters” remained in the wheel wells and other hidden compartments. This led to several pen-pal romances started by the mechanics who discovered the messages much later.
Here it was also time to install the servers for the flaps and ailerons.  I did not have to put in a throttle servo. Next it was time to build up the flaps. Flaps were built in three sections, center and right and left outer flaps. Now was time to start skinning the top of the wing. I did a double check to make sure all tasks were completed inside the wing, once it’s sheeted, there is nothing I can do. So, all look good, nothing was missing.  Now it was time to sheet the top of the wing. Outer panels were first, with the aft section of the wing. The next day it was for forward section of the wing. I had to leave the middle section undone, I was waiting on my 12-gage wire to install. (Supply issue) In this photo you can also see the build-up of the flaps. Put it all together for a look at the new DC-3, yep, she is coming together.
In my next article I will be building up the nacelles and mounting the motors in place.