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The SBD's fin subassembly prior to Pioneer de-riveting it from the upper fuselage. Note that the main attachment point for the horizontal stabilizer sits at the mating surface of the three-legged, bare steel jig fitting. (photo via Pioneer Aero Ltd.)

In mid-September, Pioneer Aero separated the SBD's upper fuselage from the airframe, mounting the subassembly in a purpose built jig (as described in our most recent restoration report). Part of this effort involved locking down the exact locations of the various attachment points for the tail fin and remaining empenage frames. With these positions now defined precisely, Pioneer was confident that they could then reposition the components accurately following their removal and refurbishing. This report details the process of detaching the fin and its associated empennage components in the leadup to their intended restoration.

Separating the fin:

Separating the fin from the upper fuselage subassembly required drilling out a number of rivets - in a specific order - from both the airframe's interior and exterior. They began by first removing a row of rivets which attach the top of Frame 15 to one of the vertical ribs in the fin, as seen in the image below.

A view of upper rear side of Frame 15 looking towards the front of the aircraft. The white discoloration is indicative of surface corrosion roughly where the Frame joins the fin rib. Pioneer had drilled out the curved row of rivets attaching the two components at the time this image was taken. (photo Via Pioneer Aero Ltd.)
A view of upper rear side of Frame 15 looking towards the front of the aircraft. The white discoloration is indicative of surface corrosion roughly where the Frame joins the fin rib. Pioneer had drilled out the curved row of rivets attaching the two components at the time this image was taken. Note: the sturdy-looking beam at image bottom is the top edge of the carry through spar for the horizontal stabilizer. (photo Via Pioneer Aero Ltd.)

Skin panel Removal

The next step involved de-riveting a small section of skin from either side of the fuselage. This particular panel blends the fin into the fuselage extending from the aft-most fuselage bulkhead at Frame 17 through to Frame 15, where the main spar for the horizontal stabilizer attaches.

. (photo Via Pioneer Aero Ltd.)
A view of the upper fuselage, with aircraft's rear-most bulkhead (Frame 17) exposed at right. The small skin panel which blends the fin into the fuselage and the horizontal stabilizer fairing below it extends from Frame 17 to Frame 15.(photo via Pioneer Aero Ltd.)

Removing the Horizontal Stabilizer Fairings:

Next, Pioneer had to remove the fairings which blend the horizontal stabilizer into the fuselage.

Removing the Fin:

To remove the fin and remaining aft structure, all Pioneer had to do now was to drill out the rivets attaching the fin fairing to the upper fuselage skin.

. (photo Via Pioneer Aero Ltd.)
The SBD's upper fuselage following the removal of the aircraft's fin and its associated structure. Note that the jig fittings which mount to the horizontal stabilizer carry through spar have been reattached. (photo Via Pioneer Aero Ltd.)