Hatz Classic #90
I started construction of a Hatz Classic in November 2005, For many years I was active in model aircraft. After owning and flying my Aeronca Chief for a few years my interests started to shift more towards the full scale aircraft. I had thought for some time about building one, but never could decide where to start or what to build. Well in October of 2005 I attended a Fly-In at Cooper's field in Mohwk, TN. I parked next to Steve Garrison in his blue Hatz CB-1. After going home and researching a little on the web, I settled on the Hatz Classic as my first project. I ordered the plans and started construction in November of 2005.

I hope to build something similar to what you see here........This is a modified version of the Hatz Classic using the ROTEC 9 cyl radial engine
This 3 view was done by Hans Gautschi and shows some of the modifications that I also want to use.
Below is a good piture of the engine that I plan to use, click on the engine for a link to the ROTEC website.



Hatz Information and Links:


Hans and Sam Aeroplane Works Project
Click the link above for Hans and Sam's Hatz Project, Great Information!



American Hatz Association Forum
This is a great forum to discuss the Hatz


Click below to E-mail Me



Construction Begins!! 12-2005
I starteded with the ribs, I wanted something small to start with that I could work on in the basement at night. I started buy building a rib jig to form the ribs in


All of the pices were placed in the jig, then glued with T-88 epoxy and allowed to dry overnight. I used wax paper under the glue joints to kepp the ribs from sticking to the jig.


After the first side of the rib was dried, I removed it from the jig and placed it into a second jig to glue the second side of the gussetts. This allowed me to start one rib each night and finish the rib I had done the night before. After all the glue was in place I placed a board over the whole assembly and weighted it down to dry.

The ribs went very smoothly. Here are all of the ribs completed (Less trimming and sanding)

Next, I decided to build the center section of the top wing, this section hold the fuel tank and is directly over the cockpit. The center section is made mainly of 1/4" plywood with spruce spars on the front and rear.

At this point I had to start fabricating some steel fittings for the wing mounts.



I started fabricating these by hand, but later found a local company who would cut the raw shapes on a water jet from CAD drawings. That saved a TON of time and made a very nice looking fitting.

Here is the completed center section bolted to a top wing panel.


Next came the construction of the wings. By this point I had taken the time to "Kit" most of the parts for the wings, meaning that I had pre-made about everything that I could think of. The leading adge and trainling edges were all made from scratch on my table saw and the spars were cut and ready to go with the outer doublers glued in place and all of the holes drilled.
First I placed all of the ribs onto the spars, then once they were all in place I glued the root doublers in place. The next step was adding the aileron spar and all the fittings and compression tubes. The two top wings are shown here, they are complete with the exception of the top leading edge sheeting, I have decided to leave it off until I trial fit everything in case some changes need to be made.



Here are the wingtips, these caused me some headache, but Iam happy with the results. They are a lamination of 1/8" ply.


I have the first bottom wing about complete, all I have left to do is weld up the linkage for the ailerons, and I just havn't taken the time to do it yet!
I might have some parts watter jetted again to make them look a little better, but I havn't made up my mind yet.



My steel tubing has arrived for the Fuse, so I have to get these wings out of the way!!!



Here are the wings pretty much finished, I still need to finish the top of the leading edge and all of the priming and painting of the fittings.
Next the wings get sealed and stored for later.
Still need to build all of the ailerons also.....



I started laying out the fuselage and tack welding the structure, it should look like an airplane before too long!!



This is the rig to cut the joints in the tubing, this thing works GREAT!! makes very nice joints!



This is the first side tacked up and ready to pull out of the jig..



Here are both sides out of the jig, ready to start putting them together!!



I jigged the sides up to get everything nice and square, threaded rod for cross bracing worked great for this
It let me adjust the side with ease



This is the bottom of the fuse under the pilots seat.......



Pulling the fuse sides together at the rear for the tailpost, there are two tapers at the rear of the fuse.

The tailpost is in!!! Time to start some finish welding......


The fuse is turned over now in the upright position to finish welding out



Here is a cluster joint, there is a lot of welding involved in each cluster, about an hour each.



This is the swing joint for the elevator



Tail supports and tailwheel mounts are done, all the little detail parts are starting to go in now!!!



This view is looking back from the front of the fuse. Those are the Torque Tube mounts and the seatbelt mounts



These are the Cabanes, they hold the center section



I couldn't help but put the center section in place to take a look!! I still have the rear mounts to fabricate.



This is the rear seat frame



This is the Front and Rear seat with the fuse upside down



Front Landing gear fitting, I added the front gussett instead of filling between the fittings like on the plans, I think this will
make a stronger joint



Just a few more parts to go and she will be ready to roll outside to try the wings on for the first time!!!




Here is the center section with the cabanes finished



4-2-2010
I have started putting on some wood templates to try to determine the final shape of the fuse, these are just temporary right now