Mid-cap share tip of the week: Senior Senior, the aerospace engineering group, may not be the most recognisable company in the FTSE 250, but over the past year it has been one of the top performers. The company, which manufactures components for the biggest aircraft builders in the world, such as Airbus and Boeing, has seen its shares rocket by 49pc over one year to 288p. According to fund manager James Henderson of the Lowland Investment Company, the stock has benefited from the firm being one of the key players in its field. It also makes parts for military helicopters in the United States, an area in which Mr Henderson said the company had struggled in recent years. But now the US economy has turned a corner he expects this market to pick up in the coming year, which is why he is buying more shares in the company, as opposed to taking profits from its stellar run. "For Senior, US defence business momentum is finally starting to build," he said. Investors are becoming more positive on the US economy. The US is by far the biggest buyer of defence, which leaves European exporters at the beginning of a potentially large share price increase. Mr Henderson said the company had £120m of cash on its balance sheet, some of which he expected to be returned to shareholders in the form of a dividend. At present the dividend yield is low, at 1.67pc. The cheapest ways to invest in shares Regular news and tips for fund investors: bookmark telegraph.co.uk/investing