We need to compare noise at takeoff and landing, and also during travel (when aircraft may fly over the top of residential communities and recreational trail users)
It would be helpful to have some objective data (decibel numbers) as well as some subjective comparisons ("what it sounds like"; "how annoying is the sound")
This video purports to show the relative sound envelope generated by different types of aircraft passing overhead at 2000 feet. It is comparing with a specific eVTOL made by Joby, and it's about 3 years old.
which sounds louder on the ground, a cessna skyhawk or a PC12?
ChatGPT 4.o
The sound levels of aircraft on the ground can vary based on a number of factors including engine type, propeller design, and operating conditions. However, generally speaking, a Pilatus PC-12 is louder than a Cessna Skyhawk.
Engine: Piston engine (Lycoming O-320 or O-360)
Noise Level: Typically lower compared to turboprop aircraft. It produces noise levels around 70-80 decibels (dB) during takeoff and landing.
Engine: Turboprop engine (Pratt & Whitney Canada PT6A-67B)
Noise Level: Turboprop engines tend to be louder than piston engines. The PC-12 produces noise levels around 80-90 dB or more during takeoff and landing.
The Pilatus PC-12, being a turboprop aircraft, generally produces more noise on the ground compared to the piston-engine Cessna Skyhawk. Therefore, the PC-12 will sound louder.
4o
how much louder does a sound of 80-90db sound than a sound of 70-80db?
ChatGPT
The perception of loudness in terms of decibels (dB) follows a logarithmic scale rather than a linear one. This means that an increase in decibels represents a significant change in perceived loudness. Here’s a general guide to understanding how much louder one sound is compared to another:
10 dB Increase: A sound that is 10 dB higher is perceived to be about twice as loud. For example, an 80 dB sound is perceived as twice as loud as a 70 dB sound.
20 dB Increase: A sound that is 20 dB higher is perceived to be about four times as loud. For instance, a 90 dB sound is perceived as four times as loud as a 70 dB sound.
70 dB to 80 dB: An 80 dB sound is perceived to be twice as loud as a 70 dB sound.
80 dB to 90 dB: A 90 dB sound is perceived to be twice as loud as an 80 dB sound.
70 dB to 90 dB: A 90 dB sound is perceived to be four times as loud as a 70 dB sound.
In summary, a sound in the range of 80-90 dB is perceived to be significantly louder than a sound in the range of 70-80 dB, potentially up to four times as loud if we compare the extremes (70 dB to 90 dB).
https://www.reddit.com/r/flying/comments/r6kven/why_are_small_planes_so_loud/
https://en.wikipedia.org/wiki/Cessna_172#:~:text=Measured%20by%20its%20longevity%20and,aircraft%20remains%20in%20production%20today.
https://www.icao.int/environmental-protection/pages/Reduction-of-Noise-at-Source.aspx