Warren Buffett is making a big move into the aerospace market, betting on the boom in the airline business. The billionaire investor's Berkshire Hathaway (BRK.A) is buying aircraft equipment maker Precision Castparts (PCP) for $37.2 billion, marking the conglomerate's biggest deal yet. Berkshire, which is already the company's largest stockholder with a 3% stake, will pay $235 a share in cash for all of Precision Castparts' shares. The offer represents a 21% premium over Precision Castparts’ closing price from Friday. Including debt, the takeover deal is valued at $37.2 billion. As part of the agreement, Precision Castparts will become a unit of Berkshire, while keeping its name and headquarters in Portland, Ore. The two companies expect the deal to close in the first quarter of 2016, pending both shareholder and regulatory approval. TheStreet's Kurumi Fukushima reports in New York.