How Airlines Are Able To Fly The Boeing 737 MAX During Its Grounding

Airlines are moving their grounded Boeing 737 MAX aircraft around the world, to escape harsh winter conditions, perform maintenance and move them into long term storage. However, many have asked how an airline can conceivably even be allowed to fly a ‘grounded’ plane, let alone one that has a critical flaw preventing airworthiness.

Boeing 737 MAX orders
The Boeing 737 MAX won’t return to service until next year. Photo: Boeing

To answer this question we need to look at the Boeing 737 MAX and why airlines are trying to move them despite the ban.

What is the story so far?

The Boeing 737 MAX aircraft is the fourth generation of the Boeing 737 design, arguably the most successful aircraft production line ever built (arguably as the rival Airbus A320 line is catching up fast). Each new generation of the Boeing 737 has added improvements to the original design, often bigger engines.

For the fourth-generation design, Boeing added such big and powerful engines that it slightly modified the aerodynamics of the aircraft. Specifically, the large engines had to be mounted closer to the rear, which increased the risk of pushing the nose too far up. As this would mean that pilots would need to be retrained (a very expensive cost for airlines and might prevent them from considering this new aircraft), Boeing decided to correct the upward push with a little nudge from an autopilot system, MCAS.

The flaw was that the MCAS took information from a single sensor, and in two cases where the sensor was broken, the system was inputted with false information. This resulted in two aircraft crashing (as the MCAS kept pushing the nose down) and killing over 300 passengers, pilots and crew.

Around the world, the Boeing 737 MAX series was grounded until Boeing was able to fix the flaw with the aircraft and provide training for airline pilots. This process is still underway and it is unlikely that the 737 MAX will see passenger flights until next year.

Boeing 737 MAX grounding 2020
Boeing’s timeline could be in jeopardy if other regulators decided to conduct their own safety checks. Photo: Boeing

Why do airlines want to move the 737 MAX aircraft?

As the northern hemisphere darkens and snow appears on the horizon, airlines are faced with a bit of a puzzle with the 737 MAX aircraft. As the planes were grounded were they stood, many were trapped across the country, or even in other countries (Fiji Airways had one MAX still in Australia when the order came through) far from their airline’s hubs.

Thus we can summarise below several reasons why the Boeing 737 MAX needs to be flown despite being grounded.

  • The aircraft is in an airport that is charging high fees, or trapped with some other financial circumstance. E.g. You can’t afford to store a jet long term at London Heathrow for example.
  • The aircraft is located in a region beset by storms, high humidity or other weather effects. It will become damaged and cost more to repair.
  • The aircraft needs to be moved from storage to a maintenance facility to prepare to be put back into active service, something that American Airlines is currently doing.
Boeing737 MAX
Airlines want to ensure that the weather or humidity does not damage their MAX aircraft during this grounding period. Photo: Boeing

How do they move the aircraft?

With these important reasons, it seems airlines have managed to get permission from aviation authorities to move these aircraft… with some catches.

The first is that a specially trained pilot needs to be onboard. The pilot has been briefed about the MCAS system and trained in a flight simulator on how to correct it. Likely this pilot is accompanied by a Boeing official to ensure that the problem does not occur.

The aircraft is also flown slowly with flaps deployed, as this prevents the MCAS system from activating.

Flight paths are preplanned and authorized by the respective country aviation departments. For Silk Air’s plans to move Boeing 737 MAX aircraft to Alice Springs in Australia, not only do they need permission from Australian authorities but also from Singapore and Indonesia. These flight plans include flying away from urban centers and ensuring that the aircraft is carefully monitored.

Lastly, these aircraft are moved one at a time, with no passengers on board and around existing traffic. What do you think of the plan to move 737 MAXs, should they be allowed? Let us know in the comments.

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To answer your question. Yes. Yes, they should be allowed to move?


How are Ryanair able to fly theirs with passengers? (737-8200?) Thanks

Tom Boon

Ryanair are yet to take delivery of their first MAXs 🙂


There is no guarantee that all government authorities will give approval by the end of the year. Therefore, best to move them to a secure environment (low humidity. near maintenance facilities ,etc) until the final OK.


I think it’s prudent the 737 Max was grounded but why wasn’t the A330 grounded after QF72? Or other Airbus aircraft after the several – obviously – computer assisted crashes? I guess it’s easier to ground a private company built aircraft vs a state sponsored aircraft.


I think you will find airbus corrected there problem straight away not wait for 2 crashes before trying to correct it.


Boeing may be a private company but got tax cuts and other subventions from the US government. So it may as well be a state sponsored aircraft company.

Greg Cairnduff

It was QF 32 not 72 and was an Airbus A380 not a 330

Neil Dziombak

Greg the flight/incident they are talking about is QF72 which was a Qantas A330 flight from Singapore to Perth in 2008 during this flight the plane nosedived out of control twice, injuring many passengers & crew


No he is correct in saying QF72 it was not a mistake. Before the QF32 incident there was QF72 in 2008 which was an A330. It had a similar issue where the computer would put the plane into a dive due to a software design flaw and faulty hardware.

Alexandros RALLIS

Once upon a time we admired a company which at the time produced the best aircraft ever built (707-320) and then we fully entrusted every aircraft subsequently built. HOWEVER, clouds appeared to the horizon when that company by elbowing the competition from the market (see McDouglas) moved its headquarters from Seattle to Chicago, i.e a “closer” place to the decision making personalities etc. Strongly believing that Boeing is an incredible company in depth of time, however I am persuaded that a policy of “STOP LOSS” has to be applied immediately, which reads as follows: The cost of scrapping 737 and… Read more »

patrick baker

love that a boeing official has to be on board for these movements. Poetic justice, yes? IT seems that for the placement of the engines , that some compensation has to be put into place, through sensors,and that the system MCAS, is not trustworthy, but something like it is needed due to the redesign and occasional erratic flight responses. No simple solution has yet occurred, and boeing is still on the public hook for all those deaths.

D Buzniak

Yes. This sounds like a great plan and maybe they need to be all stored at one place a nice dry climate like Arizona where there is storage space in 3-4 different airports. This way when the problem is finally fixed they would not have to travel all over the world to get the aircrafts.

Spencer McLennan

Was it not that the engines had to be mounted further forward to allow for greater ground clearance of the larger fan stage?

Capt. Jeff

You are correct, Spencer.

OD Salinero

The 7..Max should be allowed to fly given the planned conditions and authorized approvals from all concerned as they are doing now. Additionally it would allow those trained pilots to learn and then teach other pilots how to correctly pilot the giant plane in any unforseen circumstances. Given that the plane’s movement is critical to its maintenance and costs reduction to its airlines and owners.

David C

The ferry flights are done with flaps engaged. Much lower efficiency and speed, also lower altitude. This is done because MCAS will supposedly not engage with flaps down. In addition, the cost of in-flight training is vastly more than SIM training. (Which is the accepted industry standard). First and foremost, Boeing needs to have stable flight management software operating without concerns. Then the training can commence.


Where are the Air Canada and Sunwing 737 Max?

Ian Hughes

If the flaps have to be fully deployed to counter MCAS intervention then these transition flights are going to take quite some time to complete travelling at the reduced airspeed

Al miles

737 max ought to be chopped for scrap


As long as the appropriate precautions are taken ( as detailed ), and the authorizations are approved, then yes, they should be allowed to move / relocate their aircraft

Richard Bisby

Would I get on it……not a chance


There’s no way will i fly on a MaX or renamed version (stupid idea) for a least a year till it proves itself..Not a nervous flier at all. But. Hmmm a plane that in my mind cant be flown at all without computer assistance? Where is it all heading?

Adelard Gendron

Yes , airline companies should be allowed to move their 737-Max8 for long term storage following the guidelines put forth