Nigel,
There are plans available on the Traplet website for a Gloster Javelin - 90 inch wingspan and various ducted fan designs that could be converted to turbine power: Phil Noel Mirage range of plans, Pavel Bosak range of plans and an F18 Hornet.
Thorjet also have plan packs for various model jets.

http://www.traplethouse.com/
http://www.thorjet.co.uk/index.php
http://www.philipnoel.co.uk/Philip%2...igns/index.htm

duthie.