Here’s a great example of the ‘Wookie Howl’ from the highly efficient Pratt & Whitney PW1900G GTF engine on this KLM E2.
The Howling you hear from the engines during Power-Up is caused by ‘sonic resonance’ within the engine's combustor. Pratt & Whitney use the "Talon X" combustor, which amplifies sound at certain frequencies, especially during low engine speeds like pulling-away from a stand still, during taxiing, takeoff and approach/landing.
For more on the E2 Jet’s amazing efficiency read here https://flightplan.forecastinternational.com/2024/07/25/embraer-unveils-e-jets-upgrades-at-farnborough/
The Howling you hear from the engines during Power-Up is caused by ‘sonic resonance’ within the engine's combustor. Pratt & Whitney use the "Talon X" combustor, which amplifies sound at certain frequencies, especially during low engine speeds like pulling-away from a stand still, during taxiing, takeoff and approach/landing.
For more on the E2 Jet’s amazing efficiency read here https://flightplan.forecastinternational.com/2024/07/25/embraer-unveils-e-jets-upgrades-at-farnborough/