In the April 9, 2010, issue of the Federal Register, the FAA issued a notice of proposed rulemaking (NPRM) affecting certification of light turbine aircraft. The new rule would require "real-world" function and reliability testing — previously mandated for larger aircraft, but not required for those weighing less than 6,000 pounds. The NPRM states, in part, "Revising the applicability is necessary because advancements in aviation technology have invalidated the reasons for excluding these [lighter] airplanes." The FAA said the proposal is, in part, a reaction to the certification controversy surrounding the Eclipse 500 and would add up to 300 hours to the flight test program for a new turbine-powered aircraft. Such function and reliability testing, which was voluntary in the case of the Eclipse, will now become mandatory. According to the NPRM, several problem areas in the subsequent service entry of the Eclipse 500 twinjet would have been flagged ahead of time by the enhanced testing, including problems with: brakes, tires, engine surges from carbon build-up on static vanes, pitch and rudder trim and moisture accumulation in the pitot system. The certification process for the Eclipse 500 was controversial nearly from the start, with accusations that the FAA review was incomplete, and that it was hastened due to pressure to meet certification deadlines set by Eclipse. The comment period on the new NPRM runs through July 8.