sentences:  The combined development of the Schiehallion and Loyal fields was sanctioned in April 1996 and the oil production started on 29 July 1998.The design and construction of the "Schiehallion" FPSO vessel was contracted to the "Atlantic Frontier Alliance", an "ad hoc" contracting consortium consisting of Harland and Wolff, SBM Offshore, and Brown and Root.The vessel was designed as a simple barge form, with a length similar to a Suezmax tanker.