 Problems came to a head in August 2003, when the FAA discovered a defective fastener for the Model 45's horizontal stabilizer could break, sending the airplane into a fatal dive.The FAA grounded all Learjet 45s, across the nation, and they all sat on the ground for a month, while the manufacturer struggled to develop a fix and get it to aircraft in the field.By 2007, Model 45 operators were said to have a "love-hate" relationship with the aircraft – appreciating its exceptional combination of performance, payload and economics, but frustrated by frequent maintenance problems, often grounding the aircraft, and difficulty getting prompt and adequate product support and parts.