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Two In The Cockpit Rule, After Germanwings 4U9525 Tragedy This Is Where It Stands and Why It Matters


We’re in shock over the confirmation yesterday that the crash of Germanwings 4U9525 was the deliberate action of co-pilot Andreas Lubitz. While the New York Times had reported it had received leaked information from a confidential source who said this was the case, no one wanted it to be true.

But among the many questions this confirmation by French prosecutors raised yesterday, one was why he was alone in the cockpit in the first place, where he was able to block the entrance of the captain. This question centers on what is often referred to as the Rule of Two, the policy that two-persons must be in the cockpit at all times. Under standard operating conditions, those two individuals are the pilot and co-pilot. When either needs to leave the cabin for a short break, a member of the cabin crew replaces the pilot for the time. This practice prevents anyone from occupying the cabin alone at any time, but it is not a universal standard.

This raises questions of why it is a practice for some airlines but not a requirement for all airlines. It raises questions of whether this policy would have been effective in the case of Germanwings 4U9525, or any different situation in which the pilot remaining in the cabin might encounter a problem.

Why isn’t it a universal rule to have to persons in the cockpit at all times?

The aviation industry is governed by rules, recommendations, standard practices and established policies and procedures. While all of those sound comforting and have their benefits, they are not the same and they each have different repercussions to aviation safety.

When anything is determined to be a clear risk, one which either by common sense, the dynamics of aeronautics or learned by experience, including previous aircraft incidents, regulators make rules. A rule must be adhered to. Airlines, to keep their operating license, must comply. But there is not one universal regulatory body in aviation. There are independent regulators in different parts of the world, and each region is sovereign. They collaborate, share ideas and insights, but each decides what works best for its region. Therefore, it is possible for a rule in one part of the world to be only a recommendation in another, or the standard practice or regular procedure of a particular airline, but not mandatory.

With recommendations, even from an airline’s own regulatory authority, airlines get to choose. If they feel it works for them, they do it. If they don’t, they don’t.

In the United States, the Rule of Two is a requirement, not a recommendation.

As the FAA’s Les Dorr explains to Flight Chic:

“U.S. airlines have to develop procedures that the FAA approves. Those procedures include a requirement that, when one of the pilots exits the cockpit for any reason, another qualified crew member must lock the door and remain on the flight deck until the pilot returns to his or her station. A qualified crew member could be a flight attendant or a relief pilot serving as part of the crew.”

However, the FAA has jurisdiction over the U.S. Airspace. Its European counterpart, EASA, has its own policy.

CAT.OP.MPA.210 Crew members at stations

(a) Flight crew members

(1) During take-off and landing each flight crew member required to be on duty in the flight crew compartment shall be at the assigned station.

(2) During all other phases of flight each flight crew member required to be on duty in the flight crew compartment shall remain at the assigned station, unless absence is necessary for the performance of duties in connection with the operation or for physiological needs, provided at least one suitably qualified pilot remains at the controls of the aircraft at all times.

(3) During all phases of flight each flight crew member required to be on duty in the flight crew compartment shall remain alert. If a lack of alertness is encountered, appropriate countermeasures shall be used. If unexpected fatigue is experienced, a controlled rest procedure, organised by the commander, may be used if workload permits. Controlled rest taken in this way shall not be considered to be part of a rest period for purposes of calculating flight time limitations nor used to justify any extension of the duty period.

(b) Cabin crew members
During critical phases of flight, each cabin crew member shall be seated at the assigned station and shall not perform any activities other than those required for the safe operation of the aircraft.

These were the policies with which Germanwings complied, as explained by Lufthansa’s CEO Carsten Spohr at the press conference yesterday. 

Established policies do not prevent an airline from establishing their own internal procedures which require something more. For example, Ryanair confirmed yesterday that, though it is a European carrier, under the jurisdiction of EASA, it has long had a Rule of Two in place. So do Finnair and CSA. Though it is not a requirement, these airlines chose to implement this rule because their own internal safety teams determined it was warranted. An airline choosing to do more than the policies require, to ensure safety, is acceptable to the authorities.

The UK’s CAA, though part of Europe and collaborating with EASA has its own set of rules as a sovereign regulator. 

Richard Taylor of the UK CAA told Flight Chic:

“Following the details that have emerged regarding the tragic Germanwings incident, we are co-ordinating with colleagues at the European Aviation Safety Agency (EASA) and have contacted all UK operators to ask them to review their procedures.

“All UK airline pilots undergo extensive and regular medical assessments to determine their fitness to hold a licence. As part of this, aeromedical examiners are required to assess a commercial pilot’s mental health at each medical examination which, for an airline pilot flying with at least one other pilot, is undertaken annually.
These detailed medical assessments are in line with international aviation standards.

“We will continue to monitor the situation as the investigation develops and our thoughts remain with the friends and relatives of all those affected by this tragic incident.”

It becomes as simple as must-dos versus should-dos.

Airlines only have to comply to the must-dos of safety, but they can chose freely to adopt the should-dos of safety. In many cases, for various reasons, airlines limit themselves to the must-dos. This is why Sphor said yesterday that he did not feel there was a need to consider a review of the established procedures. It was not a must-do, and so neither Germanwings nor Lufthansa were in violating regulations by not following this practice. If it became mandatory, he suggested, Lufthansa and Germanwings would naturally comply.

Like the UK, Germany has its own independent sovereign regulatory body, which can impose additional requirements on its operators. The Associated Press has reported that a group of German airlines will meet with the LBA (Luftfahrt-Bundesamt) to consult. Flight Chic has reached out to the LBA for confirmation and there is a meeting scheduled in Berlin today “to discuss the need of a change of the actual practice,” an LBA Spokesperson confirms. This already demonstrates a change in tone from Spohr’s stance during yesterday’s press conference. The AP reports that Lufthansa is among the German airlines joining the German Aviation Association in this new review.

Yesterday, Norwegian Airlines, and easyJet both said they would adopt this rule. Air Canada, WestJet and Transat in Canada said they would implement this rule too.

Why wouldn’t all airlines want to adopt this rule immediately?

Many more might. They may even be compelled to do so, depending on the decisions regulators make in coming days. However, it’s important to consider that airlines may have other concerns over this rule. For example, an airline might feel that a second in the cockpit who is not a pilot, just doesn’t belong there. There might be concerns over distractions, or other issues which an airline’s safety team would know. What is more, aircraft are now highly automated and since this rule only affects the phase of flight which is generally less likely to be a hazard, cruising altitude, the autopilot serves just as well as a second of the crew as a human being. Besides, these are always short breaks. Thousands of flights take place every day–and have for years–without an incident like that of Andreas Lubitz deliberately crashing the A320 flying 4U9525. There is a logic to all of this too.

But even airlines which have thus far not adopted such a policy, are open to a reconsider based on the guidance of authorities in this regard. SAS, for example, is one of many European airlines which, like Lufthansa and Germanwings, does not have such a procedure in place.

An SAS spokesperson tells Flight Chic: “To start with, it’s an awful accident and terrible tragedy. If this accident result in changed rules and procedures from the authorities we will of course follow them. For the time being though and with the information we currently possess we will not change our routines but we continuously follow the development in the investigation to value if we should adjust our procedures.”

Would A Rule of Two help prevent an incident like Germanwings 4U9525?

I was asked yesterday on Twitter whether the Rule of Two would have made a difference, or whether it would help in general. Certainly, there were many expressing their skepticism over whether this practice is at all beneficial. The point made by some is that a hostile party in the cabin could overwhelm the second anyway and nothing would be accomplished.

In my opinion, this is flawed logic. We know that, when a person is in the cockpit alone, they can take over command of the aircraft and lock everyone else out. If they are alone, their chances of success are very high, nearly absolute. There is always a chance that a second could be overpowered, as critics of the policy suggest, but it is not an absolute. It is equally likely that the second person could overpower the hostile cabin occupant and regain control. They might also be able to prevent a lock out and get assistance from outside to regain command.

None of these scenarios can play out if the hostile party is alone. Therefore, there is at least a better chance of security in the cockpit with the Rule of Two in place.

I feel comfortable that this same logic drove the FAA to require this rule in the U.S. and also led some airlines who were not required by their regulators to adopt the Rule of Two to do so anyway.

It must also be said that incidents of this kind are not common.

No aircraft accident is common and a deliberate crashing of an aircraft is even more rare. As some rightly pointed out–despite Sphor characterizing the incident yesterday as unique–it is, sadly, not.

It has happened before, and warrants careful consideration by the industry to do everything possible to prevent it from happening again. 

Also in the skies:

Air Canada Reveals New Uniforms Fully Tested by Staff Over One Year Period

3 thoughts on “Two In The Cockpit Rule, After Germanwings 4U9525 Tragedy This Is Where It Stands and Why It Matters”

  1. Pingback: IATA Responds to Germanwings 4U9525 Tragedy | Flight Chic

  2. The FAA does not have a 2 person rule in place but has basically the same rule as in Europe. No second person is required for a physiological break only for a pilot rest period. Some airlines have a 2 person rule but it is not part of any written regulations that I can find.

    This has been widely falsely reported.

    The pertinent part of the FCR is

    §121.543 Flight crewmembers at controls.

    (a) Except as provided in paragraph (b) of this section, each required flight crewmember on flight deck duty must remain at the assigned duty station with seat belt fastened while the aircraft is taking off or landing, and while it is en route.

    (b) A required flight crewmember may leave the assigned duty station—

    (1) If the crewmember’s absence is necessary for the performance of duties in connection with the operation of the aircraft;

    (2) If the crewmember’s absence is in connection with physiological needs; or

    (3) If the crewmember is taking a rest period, and relief is provided—

    1. You are correct to point out that it is not a regulation under the FCRs. However, as Less Dorr from the FAA explains (quoted in this article):

      “U.S. airlines have to develop procedures that the FAA approves. Those procedures include a requirement that, when one of the pilots exits the cockpit for any reason, another qualified crew member must lock the door and remain on the flight deck until the pilot returns to his or her station. A qualified crew member could be a flight attendant or a relief pilot serving as part of the crew.”

      It is expected that airlines should incorporate the rule as part of their operating procedures which they submit to the FAA for approval.

      You are right to point out the difference–the semantics on this one is a bit tricky. We use “Rules and Regulations” interchangeably to refer to specific FAR requirements, but indeed FARs refer to regulations. Regulations are aviation laws, on the books, to which airlines have to comply word-for-word. Operational procedures can be construed as “rules” of operation, but are not regulations.

      The point in this article is that, at the time this story was published, the US was the only jurisdiction to require the so-called “rule of two” practice from operators–not by writing it into the FARs, but implicitly, by requiring that airlines include this policy in their procedures when they are submitted for approval.

      It not uncommon or unusual for the FAA to issue recommended practices–even to issue advisories–requiring any number of procedures beyond the scope of the FARs. This expedites the process of ensuring a safety practice, without the delay involved in more formal review and revision of the FARs. It also avoids the problematic implications of converting a practice into a regulation.

      A regulatory recommendation is not a regulation, but carries more weight than the regulatory authorities’ previous stance that airlines were free to decide for themselves. It’s subtle. In some cases, the FAA may opt to leave recommendations or requirements as such, without issuing a FAR revision for an extended period. EASA has now taken a similar tack, by issuing the two-crew minimum as a recommendation. Airlines are still free to choose for themselves, since this is merely a recommendation but, by formally recommending it, EASA has now put more of an emphasis on the practice. This approach ensures that no airline would be in violation of a regulation while it revises its procedures and carries out any necessary training.

      In my career, I’ve seen recommendations become standard practice without making it to the books as a FAR regulation. Regulations carry the weight of proof of purpose, this makes it necessary to define and set into formal language a set of explicit standards. A regulator may not wish to be tasked with writing such explicit standards. This is not because regulators are avoiding work, but because they do not want good practices, which can vary in their application, to become too set and too burdensome for operators to match point-by-point.

      There are often many good ways of accomplishing the same thing, and each airline will know best how to meet the spirit of the recommendation within their organisation.

      This is the case for the so-called rule of two in the cockpit, the term I used because it was the common term in the public forum. Using that term made it easier for readers to know what I’m talking about. No regularly scheduled audits to ensure compliance are required, nor will any airline be grounded for failure to implement–something which would result from a failure to meet a regulation. However, procedures manuals will be reviewed and, to be approved, should include some wording that addresses this need. The FAA already took this approach, as Dorr explains, and now EASA accomplishes a similar thing when it states in its 27 March document:

      “[O]perators are recommended to implement procedures requiring at least two persons authorised in accordance with CAT.GEN.MPA.135 to be in the flight crew compartment at all times, or other equivalent mitigating measures to address risks identified by the operator’s revised assessment.”

      Each airline will decide how to comply. Airlines will no doubt seek guidance from their regulatory representative on implementation, but each will be free to decide the best method for implementation which applies to their operations.

      Thanks for contributing. It is important to be clear on these things.

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