American Airlines Took A Boeing 737 MAX Out Of Service After Pitch Trim Issue

American Airlines took a Boeing 737 MAX out of service on Monday after it experienced a pitch trim issue enroute from Miami to Santo Domingo in the Dominican Republic.

Flight AA98 with 135 passengers (out of 172 capacity) and six crew members was flying at around 33,000 feet just south of Nassau in the Bahamas “when the crew reported a pitch trim issue, pitch trim failure and decided to return to Miami.” Fifty minutes later it touched down safely. A replacement Boeing 737 MAX operated the flight to Santo Domingo.

The occurrence aircraft, registration N302SA, was delivered to American two weeks before the MAX’s grounding in March 2019. It was taken out of service and is currently scheduled to operate from Miami to St. Croix on Wednesday. The FAA intends to investigate.

An American Airlines spokesperson tells me,

American Airlines flight 987, with service from Miami (MIA) to Santo Domingo, Dominican Republic (SDQ), reported a possible mechanical issue after departing MIA on March 29. The aircraft landed safely at MIA without incident and taxied to the gate on its own power. All customers deplaned normally, and there were no reported injuries to any customers or crew. A replacement aircraft was used to fly our customers to SDQ while our maintenance team evaluated the original aircraft.

At this point we have little detail on exactly what happened, and what the pilots experienced, although it appears that a component of the trim system failed which was not related to the MCAS system.

A ‘pitch trim’ incident raises flags with the Boeing 737 MAX because it immediately brings to mind the issues that grounded the aircraft for nearly two years. In both the fatal Lion Air and Ethiopian Airlines crashes, runaway trim was caused when faulty angle of attack readings caused the aircraft’s MCAS computer system to move the horizontal stabilizer and push the plane’s nose down. Here the pilots would have manually trimmed the aircraft.

The 737 MAX now compares data from both of its angle of attack sensors and if there’s a material difference between the sensors then the MCAS system will be inhibited throughout the flight. The system also only now activates once per incident, eliminating repetitive nose-down pitch. Runaway stab trim is inhibited automatically, no longer requiring use of a non-normal checklist. And pilots have received explicit training on the issues that occurred with the MAX previously.

Ultimately the pilots of the aircraft remained in control and landed safely. The system worked as it should. Extra attention, though, will be likely paid to this incident because it involved elevator trim and the MAX, even though it doesn’t appear to have involved the MCAS system.

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community InsideFlyer.com, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. Gary, if you had to fly for the next 52 weeks straight and all flights were to be operated by the 737 Max would you feel safe doing so?

  2. “It doesn’t appear to have involved the MCAS system”, but that is not going to stop hack want to be reporters mike Gary Leff from inferring that it did in an attempt to line their own pockets, be damned the concequences to anyone else.

  3. Plane has minor fault. Superbly trained pilots return to major maintenance base rather than fly a further distance to a down-range station with no repair capability. Everybody inconvenienced.

    No reason to print this other than drama.

  4. Had the issue been urgent a diversion to Nassau could have occurred. If not for the fact it was a Max this would not be a story.

  5. A highly subsidized industry running on highly subsidized infrastructure (very few private airports anywhere) will be discriminating on citizens based on nontransparent factors?

    This can’t end well, just like it didn’t end well when the mortgage or insurance industry tried to do the same.

  6. @Jake

    You’re right. Too much is subsidized that prevent free market forces from ironing out the kinks. Some say the free market cause these companies to take shortcuts. Not true. Knowing that Boeing and Airbus are heavily subsidized and both operate military divisions (KC46/A400/A330 tanker) allows them to take short cuts. Excessive environmental regulations and things that drive up the cost of oil cause a constant push for fuel economy over safety. The 777X for example uses folding wingtips. Is the risk worth it: probably not. Military jets have ejection seats and both jets and props (Hawkeyes) undergo constant maintenance to the degree commercial aviation does not.

    Logically, the Max should be a very safe aircraft given all the testing. I still don’t like the systems. They are too much like Airbus with using computers. Airbus is very good at using them. Boeing doesn’t have that track record. Too many compromises were made.

  7. Actually, everything worked as it should have and the pilot did what they should have. Mechanical issues happens all the time, but the MAX is under the microscope, but this time everything went as the plane was build and the pilots were trained.

    Many don’t remember the issues that Airbus had with the A320 when it first came to market. NWA pilots nick-named it the SCUD, because you where never quite sure where you would land.

    Lemon. . .I think not.

  8. Wow some very touchy people on here. What’s wrong with reporting the incident? I appreciate knowing about it. Was something factually incorrect?

    You act as if we don’t have enough sensibility to determine for ourselves if this is hype or not. Give it a rest. We don’t need you to tell us.

  9. David: The point is that journalists should have the ethics and constitution to know better than to write a defamatory story in the first place. Stating the facts is enough, the inflammatory BS for the sake of ad revenues and their own ego is wrong and should be discouraged.

    The other side of the matter is despite the fact that you might know better, the vast majority of others do not….including law makers and regulators.

    It’s not a matter of being touchy, it is a matter of demanding better from our media in this country being that a well informed people is essential to democracy and freedom.

  10. Ryan:

    Gary isn’t a journalist or the media. He’s an independent marketing machine for the shiny bits of plastic issued by various financial institutions.

  11. Exactly! You trolls that insist on attacking Gary should just read a different blog. I find most of what Gary writes, interesting and entertaining. I for one like to know about things like this. It helps me make an informed decisions about my travel choices. There is a reason that Gary’s blog is at the top of the list on Milesfeed. He has millions of readers who like what he writes about. You guys, just GO AWAY!

  12. Richard: No. I have already explained this to you. Nobody is forcing you to read the comments, or be simple minded enough to think that most of the content posted here is anything other than editorial trash. Long on BS, very very short on facts.

  13. Great article Gary. Please keep writing about stuff like this. We need to know about things like this, so we can make informed decisions.

  14. Gary Leff is still comfortable flying the Max….
    So reASSuring…
    I frequently ask the opinion of an influencer about open heart surgery….
    PEOPLE, this I where society is today: We have seen it from someone that has HEARD about it.
    My Word…..

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