Surplus Sale In the Hangar building outside the Hack Green Bunker, there will be held twice yearly sales of surplus communications & military equipment. The sales are open to the public at 10.00am. The sales will be held on the Sundays of 28th March & 3rd October 2010. Traders and members of the public with surplus equipment to sell, can download a booking form by clicking the link below. Watch this space for future event dates. Booking Form Please click HERE to download the 2010 Booking Form