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?
"Boost" is an informal name for the ATR72 "Automatic Takeoff Power Configuration System" (ATPCS) which allows for higher than normal takeoff weights.
Higher weights are allowed because the system automatically:
1) senses an engine failure
2) feathers the bad engine
3) applies up to 10% increased power to the good engine.
Theoretically a super sharp pilot could do it all just as well, but the ATPCS does it automatically for an increased level of safety.
Other aircraft manufactures may call it "Automatic Performance Reserve" (APR)
The boost function "cool down" the engine when needed, and adds 4,5% power below 4000ft, 4% power above 4000ft and 4% power when 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 2500 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 autofether it self.