How much noise do we make?

mshac · #1 09-02-20, 05:27 PM

Interesting that the 337 and the Cherokee Six had almost identical sound levels, whereas the 182 was about 14 decibels quieter. The 337 was the only piston twin in the study. It would have been more informative to see it compared against its direct competition. You can't say "we have some of the noisiest aircraft" when there were no other light twins tested. And when a Piper single can match us in loudness...LOL! Of course the jets they tested were on a whole different chart because they were so much louder than the pistons!

patrolpilot · #2 09-05-20, 12:41 PM

Interesting study. From the FAA's Noise Levels for U.S. Certificated and Foreign Aircraft, U.S. Certificated Propeller Driven Small Airplanes (14 CFR Part 36, Appendix F).

The Cessna 337H with the TSIO-360-C (the only model tested) is 78.6 dBA.

Did the airport you mention have posted noise restrictions?

patrolpilot · #3 09-05-20, 05:20 PM

One airport that I'm familiar with is SMO, which has a 95dBA limit 2,200 feet beyond the departure end of the runway for fixed-wing propeller aircraft (https://www.smgov.net/uploadedFiles/...Guide_2013.pdf). Straight up, our airplanes are below that limit.

Anyone know of other airports with posted limits.

kbecker · #4 09-05-20, 08:25 PM

I know KLGB (Long Beach CA), has noise limits with multiple community noise sensors.

Here is a link to the website which show times, location of monitors, runways, approach and take off limits, and a drawing of the airport and monitor locations.

http://www.longbeach.gov/lgb/resources/noise-abatement/

Kevin

patrolpilot · #5 09-06-20, 07:22 AM

Quote:

Originally Posted by kbecker

I know KLGB (Long Beach CA), has noise limits with multiple community noise sensors.

Here is a link to the website which show times, location of monitors, runways, approach and take off limits, and a drawing of the airport and monitor locations.

http://www.longbeach.gov/lgb/resources/noise-abatement/

Kevin

The Skymaster is well inside the noise requirements; it can operate at any time of the day at LGB.

patrolpilot · #6 09-06-20, 09:44 AM

Okay, a bit bored so I dug up everything that I could find that is current. Read the rules, how noise is determined, etc. The noise is not what is generated at takeoff, but rather max continuous power. The last link is to a spreadsheet on my server, it is an "ods" (OpenOffice), but excel will open it. The file has the GA aircraft separated in three different groups and is the latest published. I found a file that updates the list further with some additional airplanes, Cirrus, for one (which is loud). I will update the file mentioned at the bottom later as it does not effect the C337.

Honestly, I doubt there is a place that you cannot fly the Skymaster unless it has a "Noise Curfew" which restricts all aircraft. It seems that the minimum noise level that airports can restrict to is 90 dBA which is basically "freeway" noise.

The reason that the 337 entries are doubled is because the difference between front and rear propellers. Aircraft noise is still the same, sum of the two engines and airframe, but it requires two line entries.

Current Advisory Circular, 36-1H, change 1, 5/25/12, Noise Levels for U.S. Certificated and Foreign Aircraft

The Rules

General Aviation Noise

GAdams · #7 09-06-20, 10:00 PM

The airport was Beverly MA KBVY. In the A/FD there is a VOLUNTARY noise restriction of 75db between 0400-1200Z. I was simply trying to comply with the request and fly as quiet as I can given the admittedly OLD DATA. No matter what time of day I fly.

mshac · #8 09-05-20, 09:00 PM

Quote:

Originally Posted by patrolpilot

Interesting study. From the FAA's Noise Levels for U.S. Certificated and Foreign Aircraft, U.S. Certificated Propeller Driven Small Airplanes (14 CFR Part 36, Appendix F).

The Cessna 337H with the TSIO-360-C (the only model tested) is 78.6 dBA.

Did the airport you mention have posted noise restrictions?

According to that study, a P337H is quieter than a P210R - Read 'em and weep.