Caravelle's passenger door mechanism is repaired - Part 3

Tiistai 14.5.2024 - Erja Reinikainen ja Martti Saarinen


The reparation procedure of the left-hand side passenger door’s complicated opening and counterbalancing system has been described in the previous blogs and the story continues in

During the previous reparation effort the door could be opened with a manual winch, but the bungee ropes which were tested, were too weak to be used for opening and counterbalancing the door. There were also problems with the new roller chain and the door seemed to be slightly tilted. The technical team thought the problems might be caused by wrong adjustment of the cables or bungee ropes, or due to some part being bent in the process. Stronger bungee ropes were ordered from the US, and when they arrived it was time to try again to make the door work.


The attachment pieces at the door end of the new roller chain had been modified a little and this seemed to help to correct the door position. It now moved down without tilting on one side. Terminals made of copper tube had been prepared for the two new bungee ropes in the lifting mechanism, to fasten the bungee ropes to the sliding carriage and to the door lifting cables. For establishing the correct length of the bungee ropes, temporary fasteners were prepared for the rear end of the ropes to fasten them to the end cable of the bungee track. In the first phase the blue bungee rope in the middle was not changed, it remained as it had been in the previous testing.


The day was spent adjusting the length of the bungee ropes and cables, testing the door movement every now and then, and adjusting some detail once again. Some changes were also made on the bungee rope track. Eventually the door could be opened smoothly and rather lightly but closing it fully from its down position still required a fair bit of force.

At this point terminals from copper tube were made also for the rear end of the two outer bungee ropes and the temporary fasteners were removed. The third bungee rope in the middle was replaced with a sturdier one and terminals were made for its ends. With this arrangement the door could be moved with less force but closing it fully was still difficult. After some additional adjustments the door was functioning as it should, but it was not taken into operation yet. The technical team had been working for full eight hours at this point, so it was time to call it a day. Next time the installation will be completed, and the adjustments will be checked after the bungee ropes have been under tension for a longer period when the door has been shut.


During the day there were naturally also other activities going on: The assembly of the office and visitor centre (which is a prefabricated reusable and movable small building) was continued and the space was prepared for the opening hours on the coming weekend. Tables and sales items were moved from the aircraft into the new building. The broken sealing strip on the passenger door was replaced with a new one.


On the flight deck there was a time-consuming battle to open the emergency exit windows’ locking mechanism which had rusted solid. Among the material brought from Arlanda in 2022 there are two windows for both sides of the flight deck. They are in better condition than the existing ones and they will used to replace the old ones. Eventually the rust on the mechanism began to yield and the locking of the windows can be opened.


The planning of the new padding for the passenger seats was continued. A workable solution is beginning to take shape.

Photos by Erja Reinikainen.

Avainsanat: aviation history, restoration, Caravelle, OH-LEA, Sinilintu, Bluebird