Summary
We propose to adopt a new airworthiness directive (AD) for all Gulfstream Aerospace Corporation Model G-IV airplanes. This proposed AD was prompted by a report indicating that the G-IV gust lock system allows more throttle travel than was intended and could allow the throttle to be advanced to reach take-off thrust. This proposed AD would require modification of the gust lock system, and a revision of the maintenance or inspection program to incorporate functional tests. We are proposing this AD to address the unsafe condition on these products.