Airframe by Michael Crichton published in1996 351 pages.
The book is about a woman, Casey Singleton, who has just been promoted to vice president of Quality Assurance and to being a member of the Incident Review Team at Norton. Norton is a manufacturer of airplanes that sells the plains to carriers who then run airline service for commercial flight. Shortly after she is promoted TransPacific flight 545, which is a Norton manufactured N-22 plane, experiences severe changes in pitch and there is no structural damage to the plane, but the passengers are thrown about the cabin an d56 are injured and three are killed. The pilot changes his story about what happened every time he tells it. Then he and the rest of the flight crew take a plane back to china, where their airline is based, leaving Norton to find out what happened and to take the blame for it. Singleton is put in charge of finding out what went wrong on flight 545, but there is a twist. She must find out within a week because the company is relying on a sale that wont go through if the buyer feels the N-22 is unsafe. The company brings in many special teams to analyze the plane, and they are working around the clock to find the problem. Normally an investigation of this type would take a month, but they have to have conclusive results within the week or their company could go bankrupt. There are also threats of violence to all executives and non-union workers, especially singleton, because the union has heard rumors that as part of the new contract Norton will be sending the work for the wing, the most advanced part of the plane, to China, which would put many union workers out of a job. The union workers ruin expensive equipment, drop heavy machinery that comes very close to killing Casey and her new assistant, Bob Richmond, and cause other delays in the investigation, because they don't want the sale to go through.