What is the minimum time requirement for retaining MF1M-10 carbon copies?

The minimum time requirement for retaining MF1M-10 carbon copies is 90 days. This duration is established to ensure that the necessary records are available for review and verification purposes. Retaining these documents for 90 days allows for adequate time to address any discrepancies in weather observations that may arise and to comply with regulatory and safety standards set by aviation authorities. It is essential for maintaining the integrity of weather data that pilots and air traffic controllers rely on for safe flight operations.

The longer retention period serves to promote accountability in weather reporting and provides a buffer for any investigations or audits that may need to reference historical data. The 90-day timeframe specifically aligns with the importance placed on ensuring that critical weather information is accessible for both operational use and regulatory compliance.