Updating the SBD-5 Model

I continue updating the Dauntless versions that I am building in parallel to the basic SBD-3. In the previous post I updated the one important element of the SBD-5 model: its propeller (SBD-3 used an older version of the Hamilton Standard propeller). In this post I will continue this update.

While I already recreated the SBD-5 NACA cowling (see Figure 46-8 in this post), now it is time to adapt the panels behind it. I started by copying the corresponding cowling from the SBD-3. When it appeared in the place, I discovered a 1” gap between this cowling and the SBD-5 inner cowling panel (Figure 56‑1a):

Figure 56-1 Fitting the rear cowling from the SBD-3 into SBD-5

I immediately verified these cowling panels in the reference photos (Figure 56‑1b). It does not look like my mistake: the side panels perfectly fit the firewall and the upper and lower fuselage contour. It seems that this segment of the engine cowling really was in the SBD-5 and SBD-6 longer by 1”! (It seems quite probable: if the designers shifted the whole engine forward by about 3”, they could also modify this segment).

Following this finding, I modified all the panels of this cowling segment. I also modified the auxiliary “boxes” used by the Boolean modifier, to obtain thinner and higher air ventilation outlets (Figure 56‑2). (This is another difference between the SBD-3 and SBD-5):

Figure 56-2 Modifying the cutouts in the side panels

I shaped the inner surface of these outlets starting from a rectangular plane, as I did in the SBD-1 model (Figure 56‑3):

Figure 56-3 Shaping the air outlets on the fuselage sides

When the side cowling panels were finished, I modified the oil radiator air scoop, located in the bottom panel (Figure 56‑4):

Figure 56-4 Modifying the oil radiator air scoop

The photos reveal that this panel was in the SBD-5 wider than it was in the SBD-3 by about 2”, because it housed a larger (wider) air scoop.  (I suppose that they mounted in the SBD-5 a larger oil radiator, because it had a more powerful engine – 1200 HP instead of 1000 HP in the SBD-1…4).

When I finished the bottom panel, I started shaping the upper panels that cover the pilot’s gun barrels (Figure 56‑5):

Figure 56-5 Problems with the new shape of the upper panel edge

It seems that they have slightly different shape than in the SBD-3. What’s more, the protruding upper edge of the side panel (Figure 56‑5) indicates that the designers remodeled (simplified) this area altering both shapes: of the side panel and of the upper panel.

I compared these elements with all available photos, then remodeled both of them (Figure 56‑6):

Figure 56-6 Updated meshes of the side and upper panels

Note that in this SBD-5 the upper border of the side panel is not a straight line, like in the previous versions. The last mesh face that contains this edge has 5 edges, while all the other faces in this mesh have four edges. This is an intended effect — it seems that such a n-gon creates in this place the desired shape.

There is yet another difference, which you can hardly find on any scale plans: the windscreen frame (Figure 56‑7):

Figure 56-7 Differences in the windscreen frame details

In the older versions (from SBD-1 to SBD-4) it was built from the upper part and two rectangular plates on the sides. It seems that in the SBD-5 they simplified its technology, and created it from two metal stripes. The thinner, forward strip runs around the windshield, while the much wider rear strip forms its trailing edge. The pilot’s canopy hood slid under this rear strip — I suppose it better sealed this canopy edge.

I used a copy of the SBD-3 windscreen frame as the starting point. I modified most of its inner edges, recreating the “two-strip” shape (Figure 56‑8):

Figure 56-8 Modified windscreen frame

Finally the whole front of this SBD-5 was ready (Figure 56‑9a):

Figure 56-9 Current state of the SBD-5 model

In the last minute I discovered that in the SBD-5 they also simplified the upper cowling panel. In the earlier versions it consisted two hinged covers above the gun barrels and a central panel (see this post). In the SBD-5 it was just a single panel (Figure 56‑9b).

In this source *.blend file you can evaluate yourself the model from this post.

In the next post I will recreate the last remaining details for this project stage: the cutouts behind the gunner’s cockpit.