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Did the engines on the Habsheim A320 respond badly when the pilot asked for full power?

Short answer

No. Five seconds after TO/GA power was applied, engine No. 1 was at 83% N1 and No. 2 at 84%, and 0.6 seconds later both were at 91%. With the CFM56-5 it takes four seconds to go from 29% (flight idle) to 67% N1 and one more to reach 83%. Go-around power was applied late.

Published: October 31, 2026 · Updated: October 31, 2026 · Edited by Above Ten Thousand · Editorial policy

Did the engines on the Habsheim A320 respond badly when the pilot asked for full power?
Lufthansa Airbus A320-211 D AIQT 01Julian Herzog (Website) (CC BY), vía commons

How long a CFM56-5 takes to accelerate

With the CFM56-5 engines it takes four seconds to progress from 29% N1 — flight idle — to 67%. From that point it takes one more second to go from 67% to 83% N1. That is the progression described for these engines: four seconds from flight idle to 67% and one more to reach 83%.

The power request in the cockpit

The co-pilot called for TO/GA power and a go-around trajectory. The crew applied full power and Asseline tried to climb, but the elevators did not respond to the pilot's inputs because the A320's computer system had activated its alpha protection mode.

What the engines actually did

Five seconds after TO/GA power was applied, engine No. 1 reached 83% N1 and engine No. 2 reached 84%. Spectral analysis of the engine sound indicated that 0.6 seconds later both had reached 91%. Among the factors noted in the sequence are the engine speed at flight idle and the late application of go-around power. Less than five seconds later, the engines began ingesting leaves and branches as the aircraft brushed the treetops.

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