Great. Thanks for the feedback, Jean
Would love some guidance here for my noise cert. I found the relevant decibel figures here:
https://www.faa.gov/about/office_org/headquarters_offices/apl/noise_emissions/aircraft_noise_levels/
I have a Mooney M20K
I’m having trouble with
11. Noise standard (stage)
I’m going in circles here trying to figure this out. Some of the links in this thread no longer work do that may be part of it. Can anyone guess how the FAA came up with the numbers they have?
Also
18. Subject Aircraft Noise Levels: The aircraft listed on this form meets the requirements of 14 CFR Part 36 The noise Information on this document has been copied from FAA-approved AFM/RFM/AOM/FCOM, number _____________, Revision ______, dated __________
Given that I got the numbers from the FAA’s appendices and not an AFM, what official-looking details can I fill in here?
Nickmatic wrote:
Given that I got the numbers from the FAA’s appendices and not an AFM, what official-looking details can I fill in here?
Details of your AFM.
JasonC wrote:
Details of your AFM.
Oh haha yes I was overthinking that. Thank you.
Looked a bit closer into it. It’s definitely is a standard issued by ICAO for SEP airplanes. Measurements are taken when flying past at 300m. At least 6 measurements has to be done at MTOW and stabilized cruise at the highest power in the normal operating range. Then a lot of “fudge factors” are applied. MACH number corrections for the propeller vs max propeller speed, weight corrections and take off corrections. It is beneficial to have an airplane with a short take off run and a high vertical speed. It is not beneficial to have a high Vy. All these factors add and subtract decibels from the measurements.
The measurements looks easy enough, but all the fudging afterward looks rather complex with tables? and odd equations. (I don’t have the relevant ICAO document at hand).
Our club has just got its noise certificate for our DA40.It was done at the local OSAC.I asked around here and they reckon you will need to contact your nearest OSAC office to get a noise certificate for a F-P Jodel. I believe the addresses and telephone numbers of OSAC offices can be found on the DGAC website.
italianjon wrote:
The German regulations are quite specific on the dB levels allowable under which chapter the measurement is done.
The Swedish CAA revoked the noise certificate for one of our aircraft last year. The motivation was that ICAO standards don’t provide for noise certificates for that aircraft anymore. (It is a 1979 PA-28-181.) Instead we got a document certifying that the aircraft didn’t have a noise certificate! How would a German airport react to this as regards landing charges?
They even demanded the old noise certificate back, but we made a copy which we can show if need be.
Present the copy and you will be fine. As mentioned earlier, I didn’t have to provide the noise certificate even once in 800h mostly in Germany. However, my plane looks like an UL and is not very loud, so I have the benefit of the doubt.
Airborne_Again wrote:
How would a German airport react to this as regards landing charges?
I don’t know for sure. I would assume you’d pay the more expensive fee.
I’ve started to see further reductions for “enhanced” noise protection recently. Don’t know the details personally yet. But our club aircraft, with the exception of two which meet the regulations, are banned from circuits between certain hours and after sunset. I need to investigate whether I meet the noise levels.
Airborne_Again wrote:
The motivation was that ICAO standards don’t provide for noise certificates for that aircraft anymore. (It is a 1979 PA-28-181.)
That is probably correct. Looked a bit more into this, and there must have been some gradual change in where the noise standards are defined or something. From ICAO to EASA or some other bureau ? Newer planes do not have the same noise certificate, and for older planes it depends on age and when the local type certificate was obtained. It’s very weird the whole thing, and not easy to see the logic, if any ?
LT (Luftfartstilynet) only have this very old regulation. As you can see, if the plane MTOW < 5700 kg AND it received it’s type certificate (In Norway) before 01.01.1975 OR is a amateur built plane, then it must have a noise certificate. But there is also exceptions. If the airplane has been continuously on Norwegian register since before 01.01.1994, no noise certificate is needed, regardless of age.
Maybe there is something similar in Sweden. In any case, the only “new” airplanes (SEP < 5700 kg newer than 1975) needing noise certificate today are amateur built aircraft. They need to be measured after this ancient ICAO standard.
I don’t know what has happened. Maybe the noise has been moved from ICAO to EASA, or it has been moved to some unrelated (for aviation) environmental bureau, local or not.
