This incident describes rejected take-off due to the "boost" being inoperable. The reason for the RTO is obvious: engine power lower than expected.

But what is this ominous "boost" technology?


2 Answers 2


The boost function has nothing to do with the ATPCS. All ATR variants have ATPCS. It allows for take-off with reduced power, which increases engine life.

The PW127M has a "Boost" function that allows for a higher turbine temperature (ITT) at take-off when the power is temperature limited. Boost is selected ON before take-off when required. Typically, it allows for 500 kg extra payload. However, this comes at a cost: Every time boost is used, engine life is reduced.

The PW127N was specifically developed for Avianca in Colombia. They operate out of Bogota, which has an elevation of 8,700 ft. The PW127N engine has a "Super Boost" function that allows for an even higher ITT at take-off. This increases the payload by another 500 kg or so.

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    $\begingroup$ Welcome to aviation.SE! If you can add some references for this answer, that would be great. $\endgroup$
    – Pondlife
    Jan 15, 2021 at 5:39
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    $\begingroup$ Looks to be an interesting document here: scribd.com/document/426439514/Boost-Option, but scribd only makes the first page available for free. $\endgroup$
    – BowlOfRed
    Jan 15, 2021 at 17:23

The boost function "cool down" the engine when needed, and adds 4.5% power below 4000 ft, 4% power above 4000 ft and 4% power when at MCT (maximum continuous thrust)

The mentioned atpcs is a system that provides the aircraft with an increment of 10% of the total power at take take off in case of engine flame out, the power rating in normal take off has a maximum of 90% torque, if it's not limited by temp, that's 2475 shp, with the rto (reserved take off power) it's 2750 shp, that means when you take off and a flame out occurs the atps automatically add 10% power to the remaining engine and the affected engine autofeathers it self (when arming on ground)


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