Ooops posted to soon   Eric Sykes was never in the Goons - it was Spike Milligan   Or. as in the Last Goon Show of All from 1979, "Mr Spike Milligna, the well-known typing error"

He co-wrote many of the scripts with Spike including the last one, but you're right he didn't perform in the Goons. 

I was thinking of him in The Plank...  another brilliant comedian and writer of that group. 😄