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Why do planes fly over my house?
There are several airports in the metropolitan area
besides the DeKalb Peachtree Airport. These include
Hartsfield Atlanta International, Briscoe Field in Gwinnett
County, McCollum Field in Cobb County, Peachtree-Falcon
Field in Peachtree City, and Fulton County-Charlie Brown.
This does not even include the other smaller airports in
Rome, Cartersville, Gainesville, Hampton, Newnan, Clayton
County, Griffen-Spalding County, Covington, Monroe-Walton
County, and Winder-Barrow County. The FAA designs
airspace throughout the Atlanta metropolitan so air t
raffic will occur over all areas. However, overflights
will occur more frequently the closer you are to the
airport and its flight patterns.
Planes seem to be flying
over my house on purpose. Why?
When a plane or helicopter is over your house,
it is on its way to or from somewhere very specific.
Pilots do not have the time in this busy flying
area to single out one house or yard from another and
are usually too high and far away to see details.
Why don’t airplane
owners get rid of those noisier jets?
Aircraft owners like everyone else manage their transportation
budgets very much like automobile owners - they trade in
their vehicles for a newer model when it is economically
advantageous to do so. For the commercial service
airlines, the FAA mandated a phase-out program designed
to provide noise relief without undue economic burden on
aircraft operators. This was done during most of the 1990's,
so it was not done overnight. However, there is currently
no legislation in Congress requiring “hushkits” or
newer, quieter engines on jets that weigh less than 75,000
pounds. The vast majority of the jets using the airport
weigh much less than 75,000 pounds, and the ones that weigh
more must be Stage III noise compliant, just like the
commercial airliners. Stage III aircraft are the quietest
aircraft available using today’s technology.
Why are planes taking off to
the south when there is no wind blowing?
To enhance the performance of the aircraft and the safety
of the operation, the pilot must takeoff and land into the
prevailing wind if possible. Often, due to the wide open
spaces of the airport, the winds at the airport will be
different than in the local neighborhoods. Buildings, fences,
trees, etc., will diminish the wind effect in the neighborhood.
Second, the airport’s precision instrument
approach brings airplanes in for landing to the south.
When this approach is being used, this requires that aircraft
take off to the south to maintain a uni-directional traffic flow.
Why can’t airplanes
taking off to the south climb higher and fly farther south
before turning so they don’t fly over my
neighborhood?
Planes generally follow a traffic pattern that is set into place
by the FAA. Jets cannot fly farther south before turning,
because they would run into the large amount of airspace that
is used and controlled by Hartsfield Atlanta International
Airport. It is important to remember that airspace has a
vertical as well as a horizontal dimension, and Hartsfield
Atlanta imposes many restrictions on the use of airspace by the
outlying airports like PDK.
Who can do something about
low-flying planes & helicopters?
The FAA’s Flight Standards District Office or
“FSDO” investigates low-flying aircraft or aircraft
that are reported to be flying in an unsafe manner.
Call 404/305-7200 to report such activities.
The airport has no jurisdiction over aircraft in flight
or their altitudes.
Has the airport changed its
flight patterns? Is that why I notice increases or decrease
in the number of airplanes over my house?
The Federal Aviation Administration (FAA) through the
Air Traffic Control Tower located on the airport controls
the movement of all aircraft on the ground and in the
airspace over and around the airport. The FAA has NOT
changed or attempted to change without airport knowledge
any flight patterns into or out of the airport, except
in an effort to work with the airport to direct aircraft
over the busiest roads, the Interstates, and the MARTA
and railroad tracks. As was discussed above, the flight
patterns change due to bad weather and/or wind conditions,
and these patterns are generally used only temporarily until
the wind or weather condition subsides.
Why is PDK's nighttime curfew
voluntary?
The Federal government has designated PDK as being essential
to the nation's air transportation system. Therefore, PDK cannot
deny access to the airport to any specific user; this would be
considered a "discriminatory practice". Also, because PDK
is a public-use airport, it cannot limit its hours of operation
to only specific periods of the day or night. Consequently, PDK
has set up a voluntary curfew program, and this particular program
is heavily promoted in as many venues as possible.
The voluntary curfew is listed in as many
pilot reference materials as we can find. In fact, the airport
has published its own noise abatement pamphlet to get this
information out to as many users as possible. Unfortunately,
many of the operators who fly at night are not able to alter
their hours of operation due to the nature of their business.
Such operations include aeromedical operations, bank check and
newspaper deliveries, pubic safety (police), etc. But, PDK
actively identifies and then solicits operators at night to
reschedule their operating hours and has been successful
in many instances.
Why wasn't I informed that I
lived next to an
airport when I moved in?
There is no DeKalb
County requirement that sellers or realtors disclose to a
buyer that they are nearby an airport. The responsibility
ultimately lies with the buyer to research the area and satisfy
his/her concerns.
What is “aircraft noise”?
Aircraft noise is most apparent during jet takeoffs and landings.
Takeoffs generally produce the most noise, and the noise comes
from when the high pressure jet exhaust mixes with the cooler
air outside the engine.
How can jet engine noise be minimized?
While many factors determine how aircraft noise affects us,
the jet engine is the most significant producer of what we would
normally consider “aircraft noise”. Consequently,
the jet engine is the single most point at which noise can be
minimized. This is why the FAA adopted regulations requiring
commercial jets to meet noise standards. Unfortunately,
these regulations only apply to aircraft weighing more than
75,000 pounds.
The large fan-jet engines in modern Stage 3 aircraft muffle
the noise by reducing the speed of the engine’s exhaust.
In landing, these Stage 3 engines emit a hissing or humming
sound when pilots reduce power to slow down to landing speed.
As technology continues to progress, the newer Stage 3 engines
are even better than the older engines. The sound has been
diminished by lowering the speed of the fans and installing
sound-absorbing material within the engine itself.
What are the other factors that contribute
to aircraft noise?
Weather – in bad weather,
engine noise may reflect off thermal layers in the atmosphere,
making jets sound louder than on clear days.
Storms – air traffic controllers
will direct pilots around storms, or pilots may request to
deviate around a storm based on weather radar returns presented
to the pilots in the cockpit. These deviations for regular
flight patterns may take planes over areas not normally affected
by aircraft noise.
Routes/airspace – much of the
airspace around the PDK Airport is affected by the surrounding
airports of Hartsfield International, Fulton County, and Dobbins
Air Reserve Base.
Emergencies – an emergency may
prevent an airplane from landing, requiring the pilot to make
an additional approach to the airport or to use an irregular,
non-standard route to and/or around the airport.
Weight – a more heavily loaded
aircraft may affect the aircraft’s rate of ascent
keeping the noise closer to the ground for a longer period of
time.
Isn’t it true that big aircraft means
BIG NOISE?
It used to be true that the bigger the
aircraft the more noise it produced. However, all aircraft
weighing more than 75,000 pounds must be Stage 3 compliant.
When the FAA enacted rules that stated all aircraft weighing
more than 75,000 must comply with Stage 3 requirements, the
greatest effect was on the commercial service aircraft. However,
if ANY aircraft weighs more than 75,000 pounds, the aircraft
must be Stage 3 compliant whether it is used in commercial
passenger service or whether it is a modern business jet.
Consequently, the bigger, newer aircraft will be the most
quiet in takeoffs and landings. Nowadays, the smaller,
lighter, older aircraft are usually the most noisy.
From the chart below, you can see that the newer aircraft
which include the latest in technology including new
engines are the most quiet.
| Model (Stage) |
Maximum Takeoff Weight |
Takeoff decibels |
| Learjet |
| 23 (2) |
12,500# |
88.0 |
| 25 (2) |
16,000# |
93.5 |
| 28/29 (2) |
15,000# |
87.0 |
| 31 (3) |
16,000# |
81.0 |
| 35/36 (3) |
18,000# |
84.5 |
| 55 (3) |
21,500# |
86.3 |
| 60 (3) |
23,100# |
70.8 |
| Canadair |
| CRJ |
53,000# |
78.7 |
| Gulfstream |
|
|
| II (2) |
65,500# |
92.5 |
| IIB/III (2) |
58,500# |
91.1 |
| IV (3) |
73,200# |
75.8 |
| V (3) |
90,500# |
83.3 |
| Boeing |
| 727/200 |
208,000# |
102.4 |
| 737/400 |
139,000# |
82.4 |
| 747/200 |
820,000# |
102.1 |
| 757/200 |
255,500# |
86.8 |
| 767/200 |
282,000# |
87.7 |
| (from
FAA Advisory Circular (A/C) 36-1-Noise Levels of US & Foreign
Certificated Aircraft Measured in Effective Perceived Noise Levels) |
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