Summary
We propose to adopt a new airworthiness directive (AD) for all Airbus Model A300 series airplanes. This proposed AD was prompted by a report of reduction of the de-icing performance of the pitot probe over time that could remain hidden to the flight crew. This proposed AD would require repetitive detailed inspections of the pitot probe heater insulation resistance, and replacement of the pitot probe heater if necessary. We are proposing this AD to address the unsafe condition on these products.