No it's not Pepin! The White Formula Hurricane 5.9 was a COMPLETELY new design when first launched. The hull shape is nothing like the Dart 18 - being closer to a Tornado in shape but with more contemporary bows.

If you put a Hurricane 5.9 next to a Hobie 20 only a knowledgeable person would be able to tell them apart.

You must be thinking of the Stampede (also known as the Dart 20) although that did not have centreboards.