The Federal Aviation Administration has announced new procedures following the aborted landing of a presidential plane carrying first lady Michelle Obama that flew too close to a military cargo jet on Monday.

FAA spokeswoman Laura Brown said that the agency will start requiring a supervisor to monitor movements of flights involving the vice president and first lady, just as the FAA already requires for flights carrying President Obama.

"As of today, we are making the same supervisor oversight requirement for (vice president and first lady) flights in the D.C. area and at their destinations where possible," she said.

The announcement comes as both the FAA and National Transportation Safety Board launch investigations into the incident. It marked the latest embarrassment for the FAA, which is trying to tamp down growing anxiety over flying after suspending nine air traffic controllers and supervisors across the country in recent weeks, including five for sleeping on the job.

Monday's mishap didn't involve a sleeping air traffic controller. Instead, the civilian controller at the regional radar facility in Warrenton, Va., allowed the Obama plane to get too close to an Air Force C-17 plane landing in front of it at Andrews Air Force Bace.

The FAA requires a minimum separation of five miles between planes when the plane in the lead is as large as the 200-ton cargo jet because the turbulence created by the wings can be dangerous to trailing aircraft.

Michelle Obama and Jill Biden, wife of the vice president, were aboard a Boeing 737, one of the fleet of presidential passenger jets, returning from an appearance on ABC's "The View" in New York, when the mishap occurred on final approach to Andrews.

The civilian controller in Warrenton told the military's controller at Andrews that the distance between the planes was 4 miles -- an estimate that turned out to be inaccurate. The distance was just more than 3 miles.

The controllers at Andrews ordered the Obama plane to execute a series of "S-turns" in an effort to increase the distance, but that was ineffective. The military controllers weren't sure there was enough time for the C-17 to get off the runway once it landed before the first lady's plane could land on the same runway. So they instructed the Obama plane to abort its landing.

The FAA said it was investigating the incident as a possible error by controllers at Warrenton and added that the aircraft were never in any danger.

Michelle Obama's office said it would not be commenting on the incident.

After a series of incidents this year involving sleeping air traffic controllers, the FAA official in charge of the U.S. air traffic system resigned last week.

The first disclosed case of a controller falling asleep on duty occurred March 23 at Washington's Reagan National Airport. The most recent was this week, when a controller at a regional radar facility near Cleveland was suspended for watching a movie on a DVD player when he was supposed to be monitoring air traffic.

The Associated Press contributed to this report.