ZURICH: The Swiss air force has grounded five of its 30 F/A-18 Hornet fighter jets after finding tiny cracks in their landing flaps. It ordered checks of its entire Hornet fleet after an inspection detected the problem in one F/A-18C last month, it said on its website. Air defense operations and training remain ensured, it said, although it was still reviewing the possible medium-term impact on training requirements and what remedial steps would be required. Switzerland plans to replace its fleet of Boeing McDonnell Douglas F/A-18C and D Hornets and outdated Northrop F-5 Tigers, all of which are scheduled to be retired in the 2020s. The government decided in November to spend no more than eight billion Swiss francs ($8.57 billion) to purchase new fighters and missile defenses, toward the lower end of three options previously considered. The government asked the defense department to look at which aircraft to buy, and wants it to begin talks with Airbus, Boeing, Dassault, Lockheed Martin and