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The question is simple: what happens?

Is the aircraft going to stay stationary, or will the engine power overcome the brakes? I'm assuming everything is fully functional.

I know the FCOM says not to exceed 75% N1 with the parking brake engaged, but if we did, what would happen?

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marked as duplicate by Pondlife, jwenting, Community Jun 19 '18 at 13:33

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • $\begingroup$ Different question, with different answers. $\endgroup$ – Daniele Procida Jul 4 '18 at 7:21
  • $\begingroup$ @DanieleProcida but OP themselves said that the duplicate answers their question. $\endgroup$ – Federico Jul 4 '18 at 8:39
  • $\begingroup$ @Federico Where does it say that? $\endgroup$ – Daniele Procida Jul 4 '18 at 13:49
  • $\begingroup$ @DanieleProcida the fact that the "community" account has closed the post. It only happens if the OP agrees on closing the question as duplicate. $\endgroup$ – Federico Jul 4 '18 at 14:00
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The question is simple: What happens?

There is a strong chance this happens:

enter image description here Credit: spiegel.de

On 15 November 2007, an Airbus A340-600 due to be delivered to Etihad Airways crashed during ground engine test at Airbus' facilities in Toulouse Blagnac International Airport. The brand new US$250 million aircraft, damaged beyond repair. was written off

Source

And there is a stronger chance that nothing bad will happen, but when you exceed the limits clearly stated by the manufacturer of the equipment without any good reason then your insurance cover flies away faster than the exhaust air so if Airbus tells you to not exceed 75% N1 then it is safe to assume that it is not safe to go 76% N1 on both engines with Parking brakes set.

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    $\begingroup$ Wow. Talk about a bad day at the office. $\endgroup$ – a CVn Jun 19 '18 at 11:06
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The A320neo has maximum combined thrust of about 60,000 pounds; a minimum operating weight of 97,000 pounds; and maximum takeoff weight of 174,000 pounds. Typical modern tire rubber on dry pavement has a static friction coefficient of 0.9-1.1 0.9*97000=87,300 pounds of thrust needed to make the tires slide. The engines would get very hot for sure. The airflow may pick up debris and damage the engine.
Hot exhaust may deflect off the ground and heat the tail?

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    $\begingroup$ I'm confused. What would the amount of force required for the tires to slide (assuming the aircraft is completely unloaded with no fuel) have to do with how hot the engines would get? Airliner engines are designed to get hot. Very, very hot. Like, "Magma looks cool by comparison" hot. $\endgroup$ – reirab Jun 19 '18 at 19:09
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    $\begingroup$ Up until the talk of engines getting hot I thought this was a good answer. You may want to edit that out. $\endgroup$ – Notts90 Jun 21 '18 at 11:57
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    $\begingroup$ The engines are not designed to operate at full load for more than a few minutes, typically only for emergency maneuvers like an engine going out just after rotation, normal takeoffs are only 80-90% throttle. The engines are also not designed to operate at full load while static, they need to move forward for cooling and to prevent compressor stall. Compressor blades have an AoA just like wings. Turbines have temperature limits, maximum material temperature is the number one limitation on turbine design (power and economy performance) sitting at full power on the ground will melt the parts. $\endgroup$ – Max Power Jul 4 '18 at 2:10

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