Friday, April 20, 2012


G R Mohan | 5:11 PM | | | | Best Blogger Tips

The Sterile Cockpit Rule is a regulation requiring pilots to refrain from non-essential activities during critical phases of flight, normally below 10,000 feet. The FAA imposed the rule in 1981( and adopted by most regulatory bodies) after reviewing a series of accidents that were caused by flight crews who were distracted from their flying duties by engaging in non-essential conversations and activities during critical parts of the flight. One such notable accident was Eastern Air Lines Flight 212, which crashed just short of the runway at Charlotte/Douglas International Airport in 1974 while conducting an instrument approach in dense fog. The National Transportation Safety Board (NTSB) concluded that a probable cause of the accident was distraction due to idle chatter among the flight crew during the approach phase of the flight.

What are the regulatory guidelines ?

1.       No certificate holder shall require, nor may any flight crewmember perform, any duties during a critical phase of flight except those duties required for the safe operation of the aircraft

2.       No flight crewmember may engage in, nor may any pilot in command permit, any activity during a critical phase of flight which could distract any flight crewmember from the performance of his or her duties or which could interfere in any way with the proper conduct of those duties. 

For the purposes of this section, critical phases of flight includes all ground operations involving taxi, takeoff and landing, and all other flight operations conducted below 10,000 feet, except cruise flight. 

How does a flight attendant interpret the sterile period? Typically the Critical phases of flight to a flight attendant are the take-off run, the take-off flight path, the final approach, the landing, including the landing roll, and any other phases of flight at the discretion of the commander.
 In the absence of cockpit displays she needs to be given guidelines based on discernible signals initiated from the cockpit to distinguish between sterile, no contact and periods of normal communication protocol. Distractions caused by flight attendants visiting the cockpit or calling on the interphone were noted  in a number of accidents as contributory causes. Many airlines have strict enforcement policies of this sterile cockpit rule especially with respect to communication being initiated by cabin crews during sterile and no contact periods.

On July 9th, 1995 an ATR aft passenger door separated after take-off at an altitude of 600 feet (NTSB, 1995b). The flight attendant at the door stated that she did not think of calling the cockpit when she heard the sound of the door leak before it separated, because the aircraft was under sterile cockpit conditions. When queried as to what conditions she would call the cockpit when sterile, she responded that she would in case of fire or a problem passenger. Confusion over and rigid interpretation of the sterile cockpit rule is not unusual as our studies have shown.

A study by FAA observed that many flight attendants do not have a clear understanding of what "sterile cockpit" means. Flight attendants need to be given specific information about what type of information merits contacting flight crewmembers during the sterile period. Hesitancy or reluctance on the part of a flight attendant to contact the flight crewmembers with important safety information because of a misconception of the sterile cockpit rule is potentially even more serious than the unnecessary distraction caused by needless violations of the sterile cockpit.

It would be desirable for airlines to discuss specific case scenarios during periodic refresher training and lay down guidelines on what to say, when to say and how to say.


  1. Nice post. I have to say that if I were flying, I wouldn't want the flight attendant calling me for a door leak noise at such a low altitude. Reality, we are really busy flying and communicating and there is no time to decipher what a flight attendant hears.

    The question is, could they have done anything if she called them? Or, would they have been distracted by her calling them. The call wouldn't make a difference in the outcome of the door separation. But that call could have made a difference and degraded safety by adding confusion and extra talk in a high critical time before the door separated. Does that make sense?

    My rule is... Tell the Flight Attendants if they think something is happening that shouldn't be, prior to take off... speak out. If they are in a critical area of flight and think they are going to die... call. If the packs are still off... call.

  2. Good point you bring out Karlene. Faced with a situation we all prioritize our tasks and its important that flight crew is not distracted with information not critical to safety of aircraft as perceived , of course.
    Distractions could be detrimental in throwing crew off guard.