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In December of 2015 Qatar Airways flew the first commercial flight of an Airbus A350 out of the United States, from JFK in New York City. The first attempt to take off was rejected, as documented at thepointsguy.com and in many articles derived from that one:

As you can see in the video above, about 18 seconds after we began rolling down JFK’s runway 22R, the aircraft self-aborted, bringing us from more than 100 mph to a loud, screeching halt in roughly 15 seconds.

The explanation given there isn't very detailed, and may not even be correct:

(Note that while Qatar representatives communicated that the plane aborted the takeoff on its own, it’s possible that the pilots may have reduced engine power manually, at which point the A350 automatically applied the brakes.)...

...Qatar’s Chief Commercial Officer, the highest ranking executive on the flight, came over to reassure us, explaining that an “indicator” was responsible for the abrupt abort. As I understand it, for some reason the A350 decided that our 11,000-foot runway was too short to support the takeoff, and the plane applied the brakes at full force — all on its own.

After about an hour and forty minutes they successfully took off from a different runway, and the flight was otherwise uneventful.

What actually happened here to cause the takeoff to be rejected? Was it aborted "automatically" as some articles have claimed or did the pilots take some action during the takeoff roll to abort it?

Obviously I'd prefer some documentation or good sources on what happened here, but it seems unlikely that there was ever a public investigation of this incident, so I'm also open to reasoning about what systems and/or procedures in the A350 (both Airbus and Qatar-specific systems and procedures of the time) are likely to cause this sort of thing, and (to help reduce and refute wild speculation), what systems likely did not cause this.

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    $\begingroup$ Seems to me that since the question is not asking for speculation about any accident, much less one currently under investigation, it is on topic. Maybe someone will be able to provide a specific answer, or maybe not, we'll see. Sometimes questions end up being unanswered for months or years and then someone answers. And as noted, it appears that a comment has already provided content that would serve well as a partial answer. $\endgroup$ Commented Apr 16, 2022 at 11:51

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Without a report, there is no factual answer to the title question, so consider this a partial answer.

The A350 does not reject a takeoff without pilot input. An activation criteria for the RTO brakes is the deployment of the spoilers, which in a typical scenario they themselves would be armed and their activation would be signaled by idling the thrust levers.

The auto-brake RTO mode operates when:

  • All the arming conditions are satisfied.
  • The ground spoilers extend.
  • The aircraft ground speed is more than a given threshold 40 kts.

— A350 Technical Training Manual

(I can't prove a negative, but I could not find any system that was developed that would RTO uninitiated by the crew; ➤ there's also the question of the thrust levers which are not driven, i.e. they must be moved by hand, on Airbus since the A320.)

The system that could been involved nowadays, i.e. provide an indication, was developed for the A380 three years after this incident, and is now a basic functionality on the A350.

That system is explained by Airbus:

The Takeoff Monitoring function (TOM) was first developed on A380 in 2018 and is now also available on A350. TOM monitors the acceleration of the aircraft during the takeoff phase and warns the flight crew if a lower-than-expected acceleration is detected.

There's also another related system from 2018:

The second step of the Takeoff Surveillance functions (TOS2) was introduced on A350 aircraft in 2018 and is now available on A320 family and A330 aircraft. TOS2 checks that the aircraft is positioned on the intended runway and that the expected takeoff performance – based on data entered in the FMS by the crew – is compatible with the runway distance available.

Of note, the A350's ROPS from 2014 is for landing and not taking off – did it somehow erroneously activate and give a warning? I don't know.

A TOS2 warning would be:

enter image description here

Was that system being tested in-service back in 2015? I don't know.

Reading the quotation in the question: take note of the journalist's "As I understand it [...]". There is no indication that the CCO actually said what is being circulated.

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  • $\begingroup$ That's brilliant, thanks. It knocks out about half the speculation I've seen on-line about what was going on on here and gives me some systems to investigate further. $\endgroup$
    – cjs
    Commented Apr 16, 2022 at 13:11
  • $\begingroup$ BTW, I neglected into include in my initial post that the TO was aborted after an 18-second roll. TO CONFIG TEST, TOS1 and TOS2 (though not TOM) would all have had the indication up before starting the TO roll, right? $\endgroup$
    – cjs
    Commented Apr 16, 2022 at 13:21
  • $\begingroup$ @cjs: correct, and TOM is for detecting a slow acceleration early on (see fig. 6 in the Airbus article). A similar system on the 787 is also inhibited 6 seconds before V1 (not the time for distractions). $\endgroup$
    – user14897
    Commented Apr 16, 2022 at 13:42

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