![](https://flightsafety.org/wp-content/uploads/2021/06/Teterboro-crash-at-ground-impact.png)
Aircraft operators cannot be sure their pilots comply with standard operating procedures (SOPs) without a safety management system (SMS) and flight data monitoring (FDM), Capt. David Lawrence, senior aviation accident investigator for the U.S. National Transportation Safety Board (NTSB), told a Flight Safety Foundation safety seminar on Wednesday.