WASHINGTON (Reuters) - The Federal Aviation Administration told a U.S. Senate panel would need an additional 10,000 employees that would cost $1.8 billion if it were to assume all responsibilities for aircraft certification.

Some lawmakers have questioned the FAA’s decades-old practice of delegating a significant amount of the work for certifying airplanes to manufacturers, including Boeing Co, which is under scrutiny after two crashes of its 737 MAX plane within five months in Indonesia and Ethiopia.

Acting FAA Administrator Dan Elwell told the Senate Wednesday that it would require a dramatic boost in its staffing and budget to handle those duties.