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Dec 08, 2003.  Rob Tilton is making the rudders and elevators for the tail.  Here the rudders are hit wired to shape.
The rudders are going to be hinged with a piano type hinge and Rob has shaped the edge to all the hinge to be attached to the outside and still deflect the correct amount.
Dec 8, 2003.  Rob has almost finished the prop.  All it needs is a little more fiberglass on the leading edge and some paint.  Rob makes good props and is building a NC router to use to make more props.

Thanks Rob!!
Feb 6, 2004.  Chris and Lane came over tonight to help me put on the thrust duct.  It is a big duct and you really need a few people to handle it.  We cut a flat section on the bottom and then we were able to get it to fit on the 1 3/8" shaft.  You pretty much have to do the duct and engine mount at the same time to get everything to fit.  Rob did a great job building the duct!.
Feb 8, 2004.  Chris and Lane came over again to help the duct.  Last time we had not put in the engine mount bolts and the thrust duct made the mount tilt backwards which screwed up the alignment big time.  So... I purchased a loooong 1/2" bit from Home Depot and we drilled the engine mount bolt holes and bolted down the engine mount.  The carbon fiber on the bottom of the hull took time to drill through!  Very tough stuff.  I now need to cut the 1/2" rod to the correct length.
Chris setup the alignment "system" for the duct and then we squirted in some two-part foam to keep it from moving.  I will add some plywood sides and back for looks and finish adding foam to fill in all the gaps underneath.
1st picture are the side supports for the bottom of the duct.  I will FG them on and then fill with two part foam to support the duct. 2nd picture shows where they will go..
1st picture is the side supports for the duct.  They are cut at an angle to fit the duct.  2nd picture - I am reinforcing the bottom of the duct on both sides with carbon fiber.  Zach Bell mentioned that he thought their duct sagged a little and was letting the thrust prop scrape the top of the inside.  Maybe the carbon will make the duct less likely to do that.  The duct was also built with "S" fiberglass which is 15-25% stronger than normal "E" fiberglass.  The covering is wax paper to help make the surface smooth and require less sanding.
Here is one side with the wax paper removed.  It is pretty smooth and won't require too much sanding.  The carbon fiber has a layer of tight weave FG over it as it is hard to finish carbon fiber without creating a mess.
Feb 11, 2004.  Adding the top tail supports.  As I am making the tail removable, the 1x4s only stick out 4 7/8".  A splice plate will be used to connect the (w) tail and the trim wing support for the hovercraft tail.
Feb 12, 2004.    I am adding two-part foam to the tail side supports on the duct so I can blend them into the duct.
The two bottom duct supports are done and are really stiff!  I also filled the bottom of the duct with two-part foam.  I still need to trim and FG the area.  The two 1/2" PVC pipes on the inside edges of the engine support boards are for control cable.  The 3/4" PVC pipes are to allow water to drain from in front of the duct.
Feb 13, 2004.  I am laminating the duct supports that go from the engine mount to the top sides of the duct with carbon fiber.  The outer layers are FG so I can finish the supports.
Here are the two supports after being removed from the vacuum system.  I now will cut them apart and sand the edges to get rid of the extra carbon fiber and FG. 2nd picture shows the supports sanded to final shape.  They are pretty stiff now but will get noticeably stiffer over the next few days as they finish curing.
Feb 13-15, 2004. Added the upper side supports for the duct.
Mark and I made the side tail support boards.  They are shaped to fit the side of the duct.
I added carbon fiber and a layer of tight weave fiberglass to the side of the duct where the support boards are attached.  Then the support boards were glued on with epoxy mixed with cut FG fibers and finally fiberglass tape was used on the seams.
The lower duct supports were laminated with carbon fiber and a layer of tight weave FG.
When the boards were cured, I sanded them to the final size.
Here they are mounted to the duct.  I used three layers of 6 oz tape and a final layer of 3 oz tight weave tape for the joints.
    These are pictures of the mounted duct.
1st picture shows the bottom fill foam sanded and coated with an epoxy/glass bubbles mix.  2nd picture is a picture of the duct and prop from the rear.
March 3, 2004.  1st picture is the lower rudder support.  It has bronze bushings to fit the rudder shafts and is made from very heavy duty fiberglass.  2nd picture is one of the trim wing supports.  It is made from 1/4" 6061 aluminum and is twisted so the trim wing shaft is parallel with the deck of the craft.
1st picture is another view of the trim wing support. There are bronze bushings that fit in the holes and are sized for the trim wing shaft. 2nd picture shows one set of the splice plates that will be used to hold the flying tail onto the duct.  the 1 x 4 tail supports will be held between and reinforced by the splice plates.  I did not design this tail modification but the guy that did has sworn me to secrecy (absolutely true).
March 23, 2004.  I attached the front of the thrust duct to the deck with a layer of carbon fiber and a layer of FG.  I used carbon fiber and FG to made the sides of the duct ridged to (hopefully) eliminate sag issues. 
The first picture shows the start of the paint prep work on the duct.  I used a light weight fill to begin to smooth out the duct surface.  This is a big job.  The 2nd picture shows one of the two rear spar supports for WIG mode.
March 28, 2004.  Making sure the trim wing and rudders fit.  The bronze bushings need to be slightly larger as the rudder and trim wing shaft have an anti-corrosion coating and are now slightly bigger.    They were painted by John Stewart at  Space City Aircraft Finishes in Spring, TX. Ph# 281-379-1569. They are painted Materhorn White and are aircraft quality appearance. Somewhat more than what is needed but very nice.  BTW, the rudders and wing were made by Bob Zang of Universal Hovercraft.  All told, the wing & rudders cost more than anything else on the hovercraft but I needed them faster than I had time to make them.
Picture of John Stewart.  You know he has to be a good painter to have beard like that!
April 28, 2004.  I am adding the rear cover for the bottom of the duct.  It just keeps water from getting under the duct (I hope).
Sept 26, 2004.  Here is the variator mount, variator control, prop hub and rudder supports powder coated.  The variator control was a gift from Rob Tilton before he moved up to the cold north.  Stylish red knob - now to connect it to something useful....  The round tubes in between the rudder brackets are the bronze rudder top bushings.
OCT 13, 2004.  Chris Keirs came over and helped me with the rudders.  1st picture is Chris drilling the holes in the elevator to mount the upper rudder mounts.  2nd picture is me screwing on the rudder mounts.
1st picture shows the mounts in place.  2nd picture is me with the mounted rudders.  Finally!  I still have some work to do but it is getting there.
OCT 27, 2004.  Barry Blount came over and we finished mounting the bottom rudder support and added the tie rod that makes all the rudders turn together.  The rudders turn very smoothly with the bronze bushings and the UHMW plastic spacers.
Now I need to add the push-pull cable and control stick.  My drive belts should be in soon and I can then mount the variator.  It is getting closer.