July 2019 Kaman HOK-1 update by Restoration Crew Chief Rick Centore.
The major structural task in this restoration is the forward cabin roof panel which had been damaged in the 1979 tornado. In 1980 the original magnesium panel was removed. Luckily, in the following 39 years, it remained with the aircraft and became the template for an aluminum replacement. The cabin interior restoration has been put on hold until the hundreds of rivets that attach the roof panel have been installed.
The pilot and co-pilot rudder pedal assemblies have been removed and restored. The co-pilot’s have been reinstalled. The landing gear has been restored except for final painting. When you’re working on obsolete aircraft many components haven’t been produced in decades. We were very lucky to find what was described to us as the last tire tube of the type in the country. A set of main landing gear strut stops were machined to maintain the proper fuselage height.
The engine crew has made great strides in the restoration of the Pratt & Whitney R-1340. The engine mount has also been restored. When the engine has been completed it will be mated to the engine mount to form a complete power plant assembly. The engine bay is being restored as well. In many cases, helicopter engines are hidden behind sheet metal components. But not so with the HOK. There are no doors or cowlings around the engine, making it completely visible.
Other areas being worked on are the fuel cell compartment, the transmission, and the upper pylons. The co-pilot’s front hatch has been restored with the exception of exterior paint and polishing of the windows.
A bracket with large casters has been installed on the top of the fuselage. This will allow us to set the aircraft on its back. This is necessary to allow us to restore the bottom of the fuselage which would be very difficult otherwise, due to the minimal ground clearance.
We will post another update in the fall. We hope to have a great deal more accomplished during the summer months.