PipeHawk, which sells ground probing radar equipment, was one of Monday's biggest fallers after its Chairman admitted to being 'somewhat disappointed' by the group's half-year bottom line. For the six months ended December 31st, the group posted a pre-tax loss of £244,000, compared to a profit of £83,000 in the same period the previous year. This was due to an increase in both staffing costs and administrative expenses, which offset a year-on-year increase in revenue from £1.98m to £2.61m. During the period, the group continued its development of the e-Safe and e-Spade Lite product range, for which the orders for the first units have been received. The group is committed to fulfilling these initial orders during the first half of 2014.The group's Adien business remained profitable, albeit at a lower level to last year and continued to concentrate on working with major infrastructure providers. QM Systems entered the second half of the year with a healthy order book, including contracts secured with five new clients. Meanwhile, SUMO, in which the group holds a 28.4% stake, continued to consolidate its recent acquisitions in the geophysical survey market and traded at a small profit. Chairman Gordon Watt said: "Overall, whilst I am somewhat disappointed by our bottom line result for the six months, I am very happy that we have now made the strategic investment in our facilities, order book and marketing effort which we believe have laid the foundations for significant growth in the future. "I was not called upon to provide further working capital support to the company, which is a further testament to the growing strength of the group."Shares had fallen 13.81% to 4.53p by 13:30 Monday. NR