| People
Over Planes, Inc.
of Contra Costa County, California |
|
| An information group providing the community with information on the operation of Buchanan Field airport from the perspective of the community. | |
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The FAA's Circular 36-3G Rates Aircraft Noise of All Commercial Planes in Service as of 1996 (an updated version is expected soon) |
| The Circular may be officially found at this web address:http://aee.hq.faa.gov/aee-100/aee-110/AC36-3GT/index.html.
But we have a better version here: POP's Version
of 36-3G.
It is divided up into several sections: Introductory Background on Advisory Circular 36-3G -- This specifies the measurement conditions and limitations of the circular, and is well worth reading. Appendix 1 (Takeoff) -- This takes you to a page where the take-off noise numbers for over 10,000 plane-engine combinations can be down loaded in four different file formats. The HTML format is over 500K bytes, and we suggest that you use our condensed version of the file, which is around 76K Bytes and has useful information about how the numbers apply to Buchanan Field. A link to our version is provided at the bottom of this page. Many airports base their curfews and noise restrictions on this appendix. The appendix has a table of 10,000+ rows and 7 columns. Each row contains a plane-engine combination, and the 7 columns provide the following information for each plane-engine combination: MANUFACTURER AIRPLANE ENGINE WEIGHT EST_DBA FLAPS NOTES The plane-engine combinations are listed in descending
order of noise figure (EST_DBA). The type of engine used on a plane
has a large impact on the estimated noise (EST_DBA). Weight has a
secondary impact. The WEIGHT is Take-Off Gross Weight (TOGW) specified
in units of 1,000 llbs. The published Circular incorrectly identified
the WEIGHT in the take-off appendix as being "MLW" which is the Maximum
Landing Weight (which is suitable for the approach numbers). Appendix
2 (described below) and our version of Appendix 1 (Takeoff) use the correct
acronym. The FLAPS column specifies the setting of the wing flaps
that was assumed for the measurement, and NOTES identifies other measurement
conditions, as well as the presence of any common hushkits on the engines.
Hushkits are proffered by the aviation industry as being mufflers for the
engines. Their effectiveness has been a subject of debate.
Appendix 1 (Approach) -- This takes you to a page where the approach noise numbers for over 10,000 plane-engine combinations can be downloaded in four different file formats. The HTML format is over 500K bytes. We have not made a paired down version of this file (It takes over 40 hrs to do so). These numbers are of less use because there is a much wider range in the approach noise of a plane that there is in the takeoff noise, and the numbers provided in this appendix are worse case estimates. Very few airports, if any at all, base their curfews or noise restrictions on this appendix. The plane-engine combinations are listed in descending order of noise figure. Appendix 2 -- This takes you to a page where the both the take-off and approach noise numbers for over 10,000 planes can be down loaded in HTML format. The planes are listed in alphabetical order. The HTML file is 670K bytes. We have not created a paired down version of it. Reference Notes -- This is an important as it lists any significant measurement conditions, and the presence of any engine hushkits. We have replicated these notes in our version (see below). |
| POP's Version of the FAA's Circular 36-3G - Take Off Noise Numbers (Read Below Before Clicking) |
| The FAA's HTML version is over 500K bytes, and it contains several
duplicate entries, and many entries with various plane-engine combinations
which give little variation in the noise figure for the plane. The
FAA's file also uses redundant HTML formatting commands that take space
and time to process. Our version has removed the duplicate entries, and
as much of the redundant HTML formatting as possible. In addition,
we have reduced the number of plane-engine combinations for those planes
which weigh more than 150,000 llbs. These planes cannot use Buchanan
because the airport's runways are only strong enough for 90,000 llbs planes.
These planes include the Boeing 727, 747, 757, 767, 777, the DC-10 and
DC-8, and the Airbus 300 and 310. For these planes, we have retained
in our version the combination which has the highest noise number, the
combination which has the low noise number, and one or two combinations
which have noise numbers between the high and low numbers. Also,
for the plane models that have versions in more than one stage category
(I, II, or III), like the Boeing 747 and DC-8 and DC-10, we have kept the
high, low, and middle noise numbers for the various models that are in
two or more of the three stage categories.
Unlike the FAA's HTML file, our HTML file takes about 15 - 20 seconds to download and format. After your Browser says that it has downloaded 88% to 99% of the file, you will see that your computer appears to freeze-up. However, your computer has not frozen up; instead its busy formatting about 500 rows of table information. Just hang in there for a few more seconds. Unlike the FAA's version, we have color coded the rows and selected cells of the table to make it easier for you to understand, and to point out information that is pertinent to Buchanan Field. |
| The rows corresponding to the planes being proposed for use by the start-up airlines are color coded with this orange color. We have only selected those versions of the planes which comply with the County's airport noise ordinance, which is maximum limit of 78 dBA during the day, and 75 dBA during the night (planes operated by the government, police, fire department, or life-rescue companies are exempted from the County's Airport Noise ordinance.) |
| The row corresponding to Mr. West's Lear-23 Jet is color coded with this dark gray color. Mr. West's jet has regularly violated the County's noise ordinance. He has been asked to obtain a hush kit for it. |
| The life-rescue planes, which include those planes which transport organs for transplants, fly Lear-23's and other Lear planes, the latter of which are identified in our table by this lighter gray color. |
| BUCHANAN DAYTIME NOISE LIMIT (7AM-10PM) -- 78dBA -- is shown by this color-coded row. |
| BUCHANAN NIGHTTIME NOISE LIMIT (10PM-7AM) -- 75dBA -- is shown by this color-coded row. |
| There are many air-carrier planes that can meet the County's noise ordinance, but cannot use Buchanan because they are too heavy. These planes are color coded by this light orange color. As an example, all versions of the Boeing 757 meet our noise ordinance, and are rated as being more quiet than the planes proposed by the start-up airlines, but all the 757's weigh more than 250,000 llbs, more than 2.5 times the weight of the BAe-146. There are also other version of the BAe-146 that the start-ups can use. These planes are also color coded by this light orange color. In this regard, the AVRO 146- RJ planes are the improved second generation of the BAe-146's, and are about 4 dBA more quiet. AVRO International Aerospace is (was?) a subsidiary of British Aerospace (BAe). |
| If the Weight of such planes is over Buchanan's limit of 90,000 llbs, their weight number is coded with this red color. |
| If the Weight of such planes is under Buchanan's limit of 90,000 llbs, their weight number is coded with this green color. |
| Hush kits which are indicated directly on the rows (rather than with numbers in the NOTES column) are indicated in our table by bold italics type. We have only don this for planes under 78 dBA. |
| The rows corresponding to common corporate jet aircraft which use Buchanan are highlighted with this yellow color. |
| The rows corresponding to the new quiet Regional Jets (RJ's). These are 30-70 person jets that started appearing on the market in the mid 1990's. Since this Circular was released in 1996, it only lists the RJ's from Bomberdier (e.g., the Canidair). Embraer has recently rolled out its versions of the RJ's, which are not listed in the Circular. Given the new RJ planes cost substantially more than the BAe-146 and the DC-9 (12-25 million versus 3-10 million) and carry half as many passengers, there is a question of whether they will be economically viable given the proximity of Buchanan to nearby lost-cost airports (Oakland, Sacramento). |
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Click Here for POP's Version of the FAA's Circular 36-3G (It will pop-up in a separate window.) Once you pull up this webpage, you will be allowed to click some text to bring up the above legend of color-coded information in yet another webpage. |
| Back to Air Carrier Page |