Caudron?s wing struts are cleaned

Perjantai 30.8.2019 - Member of Tuesday Club


Caudron’s eight wing struts were brought from Päijänne-Tavastia Aviation Museum in Vesivehmaa to the Tuesday Club to be restored. The struts are made of wood and have a lacquered surface. The front struts are slightly heavier than the rear ones. All struts are in surprisingly good condition.


Each strut has a fabric covering at the ends, covering about 10 cm and painted using black lacquer. There are also metal insets at the ends, with hinged metal bayonets for fastening the struts on the wings. The struts are fastened by pushing the metal bayonets through the wings and locking the bars into place using castle nuts on the other side of the wing.


The restoration of the wing struts was started by cleaning the lacquered wooden surfaces and black end parts using mild dishwashing liquid. The work was finalized by wiping the surfaces with cloths dipped in clean water.


The metal insets and fastening bayonets were cleaned of dirt and rust. The hinged bayonets were unfastened to make cleaning easier.


The screw thread at the ends of the bayonets were in poor condition because of rust. The diameter of the bayonet and the thread pitch were measured, the bayonet is 8 mm in diameter and the pitch is 1,5. The thread was opened using a suitable thread cutter from the cutter die.


There is still some work ahead before all 16 strut fastener bayonets have been cleaned. One of the original castle nuts is available, the other 15 will have to be bought.


A historical photo from the Finnish Aviation Museum's photo archive shows what kind of aircraft Caudron C.59 is.

Other photos: Lassi Karivalo.

Translation from Finnish to English: Erja Reinikainen.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, Caudron C.59, CA-50

Caudron?s horizontal stabilizer is taken apart

Tiistai 27.8.2019 - Member of Tuesday Club


Before the summer break the Tuesday Club team managed to dismantle the fabric covering on the horizontal stabilizer of the Caudron C.59. (CA-59), which was used by the Air Force in the late 1920s. Also a few ribs were unfastened, too. The horizontal stabilizer has been badly bent, and it will have to be dismantled into parts to straighten it. The wooden edge of the stabilizer is in the worst condition and repairing it won’t be easy.


When the Club’s autumn season started on August 13th, the work continued by unfastening the ribs of the horizontal stabilizer. There are 11 ribs, three wooden ones and eight plywood ribs with wooden battens around the edges. The edge battens are in good condition, but the plywood parts are badly rotten. The ribs were numbered before they were unfastened.


There was busy activity around the work table when the team started to unfasten the ribs. It was hard work because the ends of the wooden battens on the upper and lower edges of the ribs had been fastened on the wooden leading and trailing edges with a fishtail joint, secured with screws.


The screws at the ends of the battens couldn’t be unfastened with a screwdriver. The screwdriver had to be used as a lever when pulling the screws out with pliers. When all the battens had been dismantled, they were bundled together with the broken plywood ribs, using painter’s tape. They will have to wait for further activities.


The wooden ribs were dismantled after the plywood ones. The team noticed that no glue had been used when building the Caudron’s horizontal stabilizer. All joints are either fishtail joints or the joints have been secured with bolts, screws or nails.


When the ribs had been dismantled, the fasteners for the stabilizer’s bracing wires on the leading and trailing edges had to be removed. The bracing wires and fasteners and their bolts were bundled together for further activities.


A historical photo from the Finnish Aviation Museum's photo archive shows what kind of aircraft Caudron C.59 is.

Other photos: Lassi Karivalo.

Translation from Finnish to English: Erja Reinikainen.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, Caudron C.59, CA-50

Preliminary preparations for repair of the Caudron C.59?s horizontal stabilizer and elevators

Torstai 9.5.2019 - Member of Tuesday Club


The Caudron c.59 (CA-50) airplane’s lower wings, horizontal stabilizer and elevators have been waiting at the Finnish Aviation Museum for the repair work to begin. The restoration of VL Myrsky, continuing for a few more years, and the ongoing repair of helicopter SM-1/Mi-1 rotor blades are still occupying the restoration space, so there is not yet space for the Caudron. However, the preparations for the repair of Caudron’s stabilizer and elevators have been started in another space of the museum.


Before starting the actual repair of Caudron’s wings and tail, a condition assessment was made. Based on the results of the assessment, the principles for the repair work will be decided. The plane will be restored, based on the principles of repairing conservation. This means that the damages will be repaired but everything worth saving will be saved in its original but cleaned appearance.


The condition assessment of the horizontal stabilizer and elevators, still in one piece, took place in late April. The fabric covering of the horizontal stabilizer is in very poor condition. There are several holes and damaged areas in the covering and the fabric has frayed very thin and it breaks like thin paper when it is touched. The fabric covering has almost disappeared on the wooden leading edge of the horizontal stablilizer. It is almost certain that none of the original fabric covering on the horizontal stabilizer can be saved. The covering will have to be dismantled and replaced.

The Tuesday Club team decided to find out how the original covering of the stabilizer has been installed. The original covering principle can be seen clearly through the holes in the rotten fabric. A strip of fabric has been fastened along the ribs of the stabilizer, fastened with another strip of fabric around the ribs. The covering fabric has been sewn onto these strips. Then the covering fabric has been tightened using shrinking dope and painted.


The wooden structure of the horizontal stabilizer has bent crooked during the years, although there are steel wire stiffeners inside. The wooden frame will have to be straightened before the covering work. The wooden frame seems to be undamaged, but the real condition will be discovered when the fabric covering has been dismantled. It is possible that rotten wood will be found under the covering.


The fabric covering on the elevators is in better condition, but fragile. Some of the original covering may be saved, but whether that is possible or not, will be seen later. The covering on the elevators has been fastenede in a similar way as on the horizontal stabilizer and the wooden frame seems intact. There is no wooden batten on the trailing edge of the elevators (and not on the wings, either). The trailing edge looks like a bat’s wing, as in the fabric-covered airplanes built in the 1920’s.

Unfastening the horizontal stabilizer and elevators


The horizontal stabilizer and the elevators are fastened to each other using ten metal hinges. The hinge roots have been embedded in the notches in the stablizer’s trailing edge and the elevators’ leading edge. The hinges have been locked in place using bolts penetrating the stablizer’s trailing edge and the elevators’ leading edge.


The hinge bolts were removed on both sides of the horizontal stabilizer. The nuts on the bolts opened easily although they were rusted, which was quite a surprise as the nuts and bolts have been in place for more than 90 years! When all hinge bolts had been removed, the elevators were pulled away from their hinges. Both elevators could be unfastened easily.


The team decided to unfasten the hinges, still fastened on the trailing edge of the stabilizer, so that they could be cleaned. This would also make the next work phases easier. The bolt of each hinge was unfastened, and the hinges could be pulled out, one by one, from their notches. The hinges were numbered so that it will be easier to install them back into their original places. The last phase was to unfasten the brackets for the upper and lower supporting wires, which are located on the stabilizer’s trailing edge on the third rib.


Caudron C.59’s (CA-50) horizontal stabilizer and elevators are now ready for the actual restoration work to begin.

Photos: Lassi Karivalo

Translation from Finnish to English: Erja Reinikainen.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, Caudron C.59, CA-50

Caudron C.59 parts were transported from Vesivehmaa to Vantaa

Sunnuntai 17.3.2019 - Member of Tuesday Club


The Caudron C.59 (CA-50) will be the next restoration project for the Tuesday Club. The two lower wings, horizontal stabilizer, elevator and wing struts were transported from Päijänne-Tavastia Aviation Museum at Vesivehmaa to the Finnish Aviation Museum in Vantaa. The Caudron has been stored in parts at Vesivehmaa and it is included in the airplane catalogue of the War Museum.


Photo: Hannu Iivarinen

The Caudron has been used by the Finnish Air Force in 1923-1929 as a training plane. The parts of the Caudron were transported by the Finnish Defence Forces and the actual transport task was a part of the draftees’ training. The two fabric-covered wings have been stored in the sea container next to the museum hall. The horizontal stabilizer, elevator and the wing struts have been in the museum hall. The main fuselage of the plane remained in the museum hall and it will be transported later to be restored.


Photos: Hannu Iivarinen

A team of Finnish Aviation Museum staff and Tuesday Club members left Vantaa very early in the morning. Their task was to pack and load the Caudron’s parts into the Defence Forces’ truck. The team had a collection of wing supports, cushions and cargo straps which would be needed in the packing.


Photo: Matias Laitinen

The weather was cold and snowy, so the team was a little bit doubtful whether the doors and locks could be opened because of the arctic conditions. However, at Vesivehmaa snow had been cleared and the doors of the hall and the container were accessible. However, some effort was needed before the lock of the container was open.


Photos: Matias Laitinen

When the Defence Forces’ truck arrived from Tikkakoski, the loading of Caudron’s parts could be started. First the two lower wings were moved from the sea container and then the elevator with horizontal stabilizers, and finally the wing struts. The parts were placed on the wing supports and cushions and secured with cargo straps on the fastening points in the cargo space. The team wanted to make sure that all the parts were secured so that no damage could happen during the transport. When everything was ready the team had a coffee break before setting on the road.


Photos: Jorma Laakso & Matias Laitinen

The truck arrived at the Finnish Aviation Museum soon after noon. The cargo straps were unfastened and the Caudron parts were moved into the Museum, but not yet into the restoration space.


Photo: Matias Laitinen

It will take a while before the Tuesday Club team and the Museum’s staff will start the restoration work of the wings, elevator and vertical stabilizer and the wing struts. Before that the Caudron’s parts brought from Vesivehmaa will go through a thorough condition assessment. Based on the results of the assessments the restoration methods will be chosen.

Traslated from Finnish to English by Erja Reinikainen.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, Caudron C.59, CA-50

Caudron C.59 will be next project for Tuesday Club

Torstai 24.1.2019 - Member of Tuesday Club


It has been agreed with the Finnish Aviation Museum that the following project for the Aviation Museum Association’s Tuesday Club will be the Caudron C.59. At the  moment the airplane is in storage at the Päijänne-Tavastia Aviation Museum in Vesivehmaa. The fabric-covered Caudron C.59 (CA-50) is in poor condition, having been in storage for more than 90 years. Its restoration work is estimated to take a couple of years.


Photo: Wikipedia

One of the main work items is to repair the damages on the covering of Caudron’s wings, rudder and horizontal stabilizers. One wing has only the supporting frame structure which is so bent that the wing will have to be straightened and covered with new material. The fuselage covering is also badly damaged. The cockpit, engine space and landing gear will need thorough repair and maintenance. In the near future it will be decided in which order the parts of the Caudron C.59 are brought to the Tuesday Club for restoration. The Finnish Air Force Museum has an 8-cylinder V-engine Hispano Suiza 8 Ab, which has been used in Caudrons and other planes. This would be a good addition to the plane under restoration.


The Tuesday Club is prepared to start working on the Caudron C.59 when the surfaces of the Junkers 50 A Junior have been cleaned and the plane moved into the II hall of the Finnish Aviation Museum. The rotor blades of the Aviation Museum’s helicopter SM-1 (Mi-1) will also be repaired first. It may be possible to begin the restoration of the Caudron while the rotor blades are still under repair. Some of Caudron’s parts will be transported from Vesivehmaa to the Tuesday Club before the end of February.


The Caudron C.59 was used for the advanced training of pilots and 3 planes were bought in 1923 from France for the Finnish Air Force. Two of the planes were destroyed in a crash. The Caudron C.59 which is at Vesivehmaa has the identification number CA-50. It did its last flight on October 1st 1929 and was put into storage.

The Caudron C.59 resembles the Caudron C.60, used by the Finnish Air Force (it had 64 Caudron C.60’s). Due to the Hispano Suiza 8 Ab V-engine the front fuselage of the Caudron C.59 is slightly narrower than the thick nose of the Caudron C.60 with its rotating Clerget 9 star engine. Most likely the Caudron C.59 CA-50 in Finland is the only remaining individual of this plane type in the world. The Caudron C.60 (CA-84), restored by the Tuesday Club, is on display in the Finnish Aviation Museum.

Photos: Lassi Karivalo except when separately otherwise mentioned

Translation: Erja Reinikainen

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, Caudron C.59, CA-50