Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Raytheon Model Hawker 800XP airplanes. This proposal would require replacement of certain existing pitot probes with new probes. This action is necessary to prevent loss or fluctuation of indicated airspeed, which could result in seriously misleading information being provided to the flightcrew. This action is intended to address the identified unsafe condition.