Hans U & Samuel D Gautschi Hatz Classic Project: rotecradial

Hans & Sam (Sam is the son of Hans) Write (2005):

Hans & Sam Have a Website: http://www.aeroplaneworks.ch

1. Hatz Classic modified to look like a vintage Waco, by Hans & Sam Gautschi, Switzerland
2. A life long dream came true when back in the Spring of 2004 my son told me about his strong desire to build an airplane with me. I was delighted as I've always wanted to build a real airplane instead of the many years spent building and flying small scale models.

My Son's suggestion changed thoughts on what I thought could and or would ever happen! After raising two children, a married guy should have family things to do in the evening rather than building airplanes. Luckily for me my wife Therese supports us in our joint project.My Son and I have always loved vintage airplanes, especially biplanes, so the choice to build a Hatz was not a difficult one to make. But that really came later as our first considerations centered around a replica Gipsy Moth (mostly for the looks and the ability to fold the wings). The limiting factor in selecting a Gipsy Moth was the lack of a reliable and serviceable in-line engine which made the project unfeasible; so it was that we settled on the Hatz biplane, which despite not offering folding wings, became our choice based on 3 reasons:

• Another home builder in Switzerland already was building a Hatz Classic and, being an aircraft engineer by profession he did all the stress calculations (requirement in this Switzerland!)
• The availability of the Rotec R-2800 radial engine and subsequently the R-3600. The Rotec Radial is a natural fit for the Hatz (or is it vice versa?)
• The Hatz CB-1 is a well proven design and the Classic is an extension of the CB-1 with some beefing up to accommodate a 160HP flat engine. The Classic in design is more pleasant aesthetically and matches the desirable look of the late 1930's Waco biplane in design. The basic Hatz Classic design provides a perfect base which can accommodate small cosmetic and design changes.

Initial discussions about the suitability of the Rotec 7-cylinder radial started a lively discussion about the feasibility of this engine as rated at 110 HP power the concern was it would be under powered for the craft; but the advent of the 9-cylinder R-3600 it solved this concern and we moved forward with our plans and in 2005 and we placed an order for a R-3600 for our "Classic" at Osh05. Our forward planning and goals were to use the Hatz Classic plans as a base, but undertake the following modifications to achieve a vintage "Waco"- like look: 1. New elliptical tail-plane and modified fin design with ground adjustable incidence device. The fin is separated from the fuselage (can be removed). The area between stabilizer and fin is closed with an aluminum panel. 2. High pressure "Bendix" wheels and undercarriage streamlined with a wooden superstructure, fabric covered. 3. New lofting of fuselage with small "cosmetic" modifications to the ground and side view. This included a new all wood turtle deck with large baggage compartment (post sack) accessible by a side hatch. Rising the front of cockpit decking for a racy, vintage look and better blend for the radial engine. Omitting all but two stringers on the fuselage sides. 4. The collector ring will be enclosed within the front fuselage paneling like on a Waco QCF or a Stearman. Carburetor and cockpit heat will be taken from this surrounding. 5. Changing the plans for the wing at the tip, center section and lower wing to fuselage so as to follow closely the Waco QCF design. This includes a new wing tip bow design following the skeletal slope of the airfoil. 6. Fabrication and installation of a special built speed ring for the R-3600 In the final analysis, we are trying to build a vintage looking 1930's biplane by using modern materials and methods to achieve our goal. Our thanks go to American Mehlin Smith, who's custom vintage Hatz which greatly influenced our thinking on the project (see picture at left showing a red/cream Warner powered Hatz)Our efforts, as a father and son team, are towards living our dream, and achieving our dream! In the process we're having a great time!Stay tuned! - Hans & Sam Gautschi (H.C. #78, Switzerland)

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From: Samuel Gautschi
Sent: Wednesday, 25 June 2014 4:26 AM
To: Paul Chernikeeff
Subject: RE: First flight of Rotec R3600 powered "Vintage Hatz"

First flight photos of Rotec R3600 powered "Vintage Hatz"

Best regards Samuel

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April 8, 2014 - Hans and Sam write:

From: Hans Ulrich Gautschi
Sent: Tuesday, 8 April 2014 1:56 PM
To: Paul@RotecAerosport.com
Cc: 'Samuel Gautschi'
Subject: "Vintage Hatz" taxing photos and video

Dear Paul and family,

We would like to let you know, that we have our Hatz finished and are awaiting sign off for first flight (which takes it’s time in this country!).

The aeroplane is on the airfield and your engine runs flawlessly although a bit oily in the beginning (so far everything sealed, no oil exciting except exhaust). We are very happy with it’s behaviour and sound….

Thank you so much for creating such an engine without it this project would have never been possible!!!

Please find enclosed some pictures and a link to a new taxiing video on youtube:

< http://www.youtube.com/watch?v=9tK95CrNOsw

Kindest regards - Hans & Sam, Switzerland

Rotec R3600 Powered Hatz Classic undergoes ground testing with flight approval imminent

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Jun 23, 2013 Plane nears 100% Completion with the start of ground testing;

These are the First Rotec (R3600) Engine Runs on this Hatz

Click on thumbnail to see this sensational Hatz come to life ...

7th March 2013 Hans writes: We hope to have authorisation to make the first flight this late summer!!! .

We will be able to take 'completion' pictures of of the Hatz/Waco when its ready to fly in the early summer (at the moment we are waiting on flying wires).

We are currently in the final stages of painting and finishing on a colour scheme, In fact we have completed the paintwork on the 4 wing panels and the center section and the aeroplane all of which are ready for final assembly and engine testing. < Parts being painted - next stage the fuselage!

P.S. I would like to point out that my son Sam (31 years old) has done all of the sheet metal work as he is a master sheet metal craftsman. I on the other hand will take most of the credit for the on the design changes made to introduce a vintage WACO bipe influence.

< Photo oppposite Left to right : Hatz/Wako, Rotec Radial R3600 mounted with speed ring and prop, Hans then Sam. We have progressed beyond this stage to covering and painting (see above).

Hans & Sam, 4th of November 2010: Rotec R3600 mounted and a speed ring added. Work on the wimgs under way

From Hans & Sam, 23rd of April 2008: ... Great progress in a quality build ...

Dear Rotec First of all I want to express my sincere thanks for all your consise and qick support you are giving us on the matters relating to mounting the engines and the accessories that are available. This project would not have been realised without a Rotec Radial being available. and as the aircaft under construction is reasonably large it requires a radial larger than your R2800 - when your R3600 was released by you we had an engine to fit perfectly to the plan to build a Hatz Classic. Thank you Rotec! We have made good progress in the build as the photos indicate. As we progressed we decided to make mods to the Hatz Classic deign and you may notice a WACO influence in the supplied photos. . Building a biplane of this vintage design has been a life long dream of mine; however, I had to wait until Rotec came up with the 150HP Radial R3600 engine before contemplating a build. At the time you released the R3600, to my delight, my son Sam approached me with the idea to build 'the' aeroplane with me. Thank you aagain Rotec for not only providing an engine for my dream but to also have my son, Sam, join me in the endevour. I hope you and your readers will enjoy the photos as we progress (right >)

From Hans & Sam, 27th of March 2008: ... next a mounting frame for a Rotec R3600 and consideration for accessories such as oil tank, fuel tank, Rotec electric fuel pump, TBI, instrumentation (gauges) ... etc

Great progress towards Rotec Engine mount...

From Hans & Sam, 23rd of November 2007: Fuse is nearing completion and thoughts are turning to mounting an engine

Hatz Classic Tail fethers...

Fron Hans & Sam, 1st of March 2005: This fuselage is eagerly awaiting your beautiful 9 cyl. radial engine! How

Boys will be boys ...

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