I was in the UK a few years ago and was lucky to get a couple of the last pints (ever) of the Bass/Worthington White Shield IPA from the Bass Museum in Burton Upon Trent. (The museum was closed because the US parent company - Coors - decided to close the museum and the museum brewery was decommissioned).
Drinking this superb ale in the Mecca of British brewing was Nirvana - so I have designed a clone based on the recipe provided by Graham Wheeler and Roger Protz in their book, "Brew Your Own British Real Ale". I have had to adjust the amount of hops called for in the book, because according to BeerSmith the amount recommended would produce an IBU of 87! The book states that the resulting IBU is 40. I also upped the colour by added a bit more crystal malt than the recipe calls for, I may relent on brew day.
White Shield:
Grains
8 lbs 11.6 oz Pale Malt (2 Row)
1 lbs 4.7 oz Caramel/Crystal Malt - 60L
Hops
20g Challenger [7.50 %] - Boil 60.0 min
15 g Northdown [8.50 %] - Boil 60.0 min
10 g Northdown [8.50 %] - Boil 15.0 min
Yeast
1.0 pkg London Ale III (Wyeast Labs #1318)
Beer Profile
Est Original Gravity: 1.054 SG
Est Final Gravity: 1.016SG
Estimated Alcohol by Vol: 5.0 %
Bitterness: 42.4 IBUs
Est Color: 9.8 SRM
Method
BIAB with a recirculating pump to keep the grain active. This is an untried method for me, but I am optimistic it may produce a 70% efficiency. (I may be adding some DME at the boil to get the hydrometer up to 1.050.)