Step 3 - Front Seat Thigh Supports
I constructed the seatpans on my workbench then fitted them to the plane. I formed the lip over the instrument panel in a separate step using a 2-BID tape (shown on starboard seatpan) and forcing it to 90 degrees using a jig (shown on port seatpan) . I constructed the rear seatpans the same way. From a cosmetic point of view, I wondered why the front seatpans didnít extend outboard all the way to against the fuselage sides. I asked Nat about this and he said (a) it was the simplest way to make the seatpans without a lot of custom-fitting, (b) the width is more than adequate for normal-sized butts, and (c) he uses the space between the seat and fuselage side for storing things such as a survival knife and odds and ends. And as John Slade told me, he extended his seat foam and upholstery to hide this area. What a neat place for a fire extinguisher, peanuts, and a drink holder J? Nat also told me that his front seat pans are not glassed in. The seatpans are not structural, so he made his to be removable so he can use the area under the front seats for more storage.
Addendum 11-12-07: I decided to incorporate Dennis Passey's front seat modifications. His idea was that his thighs only touch a portion of the forward seat pans. His thighs didn't touch the section that meets up with the instrument panel. So he cut a few inches off the front edge of the seats. He also cut out the lower portion of the instrument panel. Then he angled the seats downward to the floor. I modified my seats and I like the results. The modification provides more room for getting my big size-12 feet through the leg openings. My heel clears the front seat edge without having to turn my foot sideways. The mod also allows me to place my foot more directly onto the floor just ahead of the seat. This helps me get in and out of the plane.
Here are some pictures showing my installation. In the first picture, you can see that I cut 3 inches off the front of the seatpans and added front closeout panels. The next two pictures show the doors I added to the front closeout panels. The doors allow me to retrieve items stored under the seats, as well as keep items from spilling out from under the seats when the plane is parked nose-down. I also installed a compartment bulkhead under each seat pan to keep retrievable items from sliding too far aft in flight. The bulkhead under the pilot's seat provides the structure for holding the inboard end of the retractable step. The last two pictures show the completed installation. According to the plans, the front seat pans are not held down by anything. They just sit on top the seat ribs. I didn't care for this. There have been a few times that the front seat pan has slid forward while I was attempting to get in and out of the plane. So I installed hinges on the back edge of the seatpans just like we're told to do for the rear seat pans. Thus, I can lift the seats and gain access to both storage compartments under the front seats. I can also remove the seatpans by pulling the pins. Notice that I added BID pads under the outboard hinges. The inboard hinges rest on the 4-UNI, 3-BID layup holding the front seatbelt attachment onto the center heat duct. Without the outboard pads, the outboard corners of the seatpans do not touch the fuselage floor. So, I added the BID pads (6 plies) to fill the gap so that the back edges of the seatpans stay level.
I'm extremely pleased with the entire installation. But before you try this at home, please understand it's a personal preference thing. Others prefer to keep the seatpans per plans. Some have even extended the seatpans more forward. I guess it all depends on how you sit in your airplane. I tend to sit with my knees flexed. So the mod works great for me. If you sit with your legs straight out, then the mod may not work for you. One thing's certain, the mod opens up the leg hole. It's alot easier to get your feet and legs through the hole. And...and...I really like my doors.
Step 5 - Rear Heat Duct Cover
I blazed away and slapped this thing together gluing the foam pieces together first, then glassing the outsides. The cover is narrow and it was a challenge to glass the insides. If I did this again, I'd construct this thing just like we did for the front and rear heat ducts -- that is to cut out the foam, glass the insides first, then glue the pieces together and glass the outsides. Maybe the plans tell you to do it that way, I dunno. At this point, you're building inside-the-fuselage cosmetic things that aren't structural. Things seem pretty intuitive and your skills level is higher, so you tend to just "do it" without referencing the plans too much.
Step 6 - Back Seats
I decided to make one rear seat bulkhead to close off the entire back end of the plane instead of making two smaller seatbacks. (See picture above.) This is more cosmetic than functional. It will be screwed into place and not permanently glassed to provide access to the landing gear bolts. If later I find I need access to storage space, I can always convert the rear seat bulkhead to incorporate two hinged and/or removable seatbacks. I made the rear seat pans and installed the support bulkhead per plans. But I waited a few years before permanently installing them into the fuselage. It's December '07 and I'm sort of winging it -- that is, not using the plans. I recall the plans saying something about using a hinge. So I riveted the forward half to the seat and floxed the rear half to the fuselage floor. Pins are used to connect the hinge halves. Note the large holes on the rear hinge half. These provide the teeth for the flox to grab on to. I applied 1 BID over the rear hinge halves. I can pull the pins out and remove the seat pans if I need to.
I didn't see "spar covers" listed anywhere in the plans. But since the forward face of the spar forms part off the rear seat, I decided to document the spar covers here. These simple covers gave me hell. When we construct the flange around the holes in Chapter 14, we aren't told to make them wide enough. Mine didn't have enough of a lip to mount on nutplates. So I grafted on some tabs. Two screws and two nutplates hold the covers in place.
Step 7 - Landing Brake and Battery Cover
I won't be fabricating a landing brake cover since I installed an electric actuator to deploy/retract the landing brake. Sorry, no story or pictures for that here.
The battery cover fits above the spar. It provides the headrests for the back seaters and hides the battery and the electronics that get installed onto the inside of the upper firewall. It fairly simple to construct per plans. But since my turtleback is different than plans, I had to make my own pattern. The first two pictures show how I make patterns. I cut a thin piece of plywood to roughly the size I needed, then clamped it onto the spar. I then taped little pieces of cardboard flush against the turtleback to determine the shape. I transferred the pattern to the foam, then spent a few minutes sanding the contour to ensure a good fit. I glassed both sides with BID. I was going to get fancy again and mount the thing with hinges so I could open and close the cover. Nah, screw the cover!! (ha, ha) I glassed on 4 tabs to receive the cover -- 2 on the inside of the aft turtleback and 2 on the top of the spar. I made these with 4-BID. Once cured, I drilled the holes and attached the nutplates. With that, I am finally finished with everything between the firewall and the front seatback. Glad that came to an end because it's pure hell trying to squeeze and maneuver in those rear seats.