Summary
We propose to supersede Airworthiness Directive (AD) 2013-03- 23, for all Gulfstream Aerospace LP (Type Certificate previously held by Israel Aircraft Industries, Ltd.) Model Gulfstream G150 airplanes. AD 2013-03-23 currently requires revising the airplane flight manual (AFM) to include procedures to advise the flightcrew of certain runway slope and anti-ice corrections and take-off distance values. Since we issued AD 2013-03-23, a revision to the AFM has been issued, which modifies runway slope and anti-ice corrections to both V1 and take-off distance values. This proposed AD would require revising the Performance section of the AFM, which includes the revised procedures. We are proposing this AD to prevent the use of published, non- conservative data, which could result in the inability to meet the required take-off performance, with a consequent hazard to safe operation during performance-limited take-off operations.