Ken, the original Watts props fitted to the Spit and Hurricane were indeed fixed pitch props. Later props were wobbly ones, ie variable pitch
This shows the various props
http://spitfirespares.co.uk/propellors.html
I have "spoken" via email In the past with the chap that produces the pens ( nothing to do with me ) and he told me he only uses props that are fit for nothing else, ie well past the possible display standard.
Sorry for the thread drift.
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