Israel has signed a letter of offer and acceptance for the purchase of nine AH-64D Apache Longbow helicopters, Boeing said yesterday. The Boeing-built Apaches and related support and equipment are expected to cost about $500 million, the company said in a statement. Israel signed up for eight AH-64Ds last year ( DefenseAlert , Sept. 26, 2000). Other international Apache Longbow customers include The Netherlands and the United Kingdom. Also, "Defense forces from several international customers . . . are considering...