Noise - Always a Nuisance

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All Other Spaceports Launch Over Water - Not Over People

Here, for the very first time in the US, space launches are being planned where residences and private property are directly physically in front of the launch area. It is a fact that at NO US vertical launch spaceports are residential areas located in front of the launch pads. At all other sites, launches take place directly over the ocean. At no other spaceport is private property or a National Seashore or National Wilderness Area overflown. The nearest occupied private property at US spaceports:

 

  1. Vandenburg Space Launch Center, Ca. - 9.3 miles behind (E)

  2. Kodiak Launch Complex, AK – 4.7 miles behind (N)(4 properties)

  3. MARS Wallops, Va. – 6.4 miles parallel (N)

  4. Kennedy Space Center Pad 39A – 11.4 miles behind, 10.7 miles parallel(S)

  5. SpaceX Boca Chica, Texas – 5.10 miles behind (N)

  6. Spaceport Camden

                    i.      – 4.75 miles directly in front (E), 1st African Baptist Church Historic Site

                   ii.      – 3.80 miles directly in front, Cumberland National Seashore(East of Launch Pad)

                  iii.      – 5.10 miles parallel, Dover Bluff (North of Launch Pad)

                  iv.      – 6.61 miles in front, Jekyll Island (NE of Launch Pad)

                   v.      – 3.63 miles parallel, Cabin Bluff (South of Launch Pad)

Noise Follows the Rocket's Trajectory

If sound is measured strictly from the launch pad, as is done for the Environmental Impact Study, a misleading noise profile is generated. Actually, the rocket engine noise source moves vertically overhead, then arcs past where residents will be directly under the sound cone. For instance, the noise from a Boeing 737 at 6,000 feet is 90dBa. You do not have to be directly underneath the 737 to hear the noise. The SpaceX Falcon 9 rocket being used by Spaceport Camden as an example of what they expect to launch is 28.3 times more powerful than a Boeing 737-800, and correspondingly noisier. Showing launch pad based calculations are misleading since the rocket travels aloft.

There are Many Trajectories - Spaceport Camden Is Showing Only One

This noise nuisance is not accurately portrayed in presentations supporting the spaceport because Spaceport Camden is showing a single, example trajectory that is most favorable to their argument. However, every launch will require its own specific trajectory that is specific to that launch. And all other trajectories will have greater Noise impacts than spaceport supporters have presented. It is unlikely that the FAA would approve a trajectory directly over or close to any residential area. The County is now hedging on the trajectories they propose on their website and now verbally present much more limited azimuths. This is precisely because of the noise and safety issues involved in flying over land rather than directly over water. The economics of limited launch trajectories have not been addressed by spaceport proponents.

Noise is Louder and Travels Farther Over Water

Both scientific and empirical evidence demonstrates that noise travels farther and is perceived louder when it travels over calm water. At every previous spaceport, the impact of sound traveling over water has not been considered because people did not live in front of or underneath the flight trajectories. However, at Spaceport Camden, noise generated by launches and engine tests will be directed over water and marsh to residences at Dover Bluff, Jekyll Island, Cumberland Island, Mush Bluff, Cabin Bluff and Elliotts Bluff.

Will Rocket Noise Be A Problem To You?

The issue is not just the Noise numbers. The main concern for citizens will become the Noise Disruption to their normal lives caused by several minutes of unusual noise and vibrations that will come with rocket engine tests and launches. Noise Disruption will be a perception that depends on what is 'normal' where they live or work. The effect could be dramatic and startling, or it could be annoying (for instance, like when you are in a theatre watching a quiet pastoral scene while the adjacent theatre has a Star Wars action scene.)  
In a quiet wooded neighborhood on Harrietts Bluff Road or Dover Bluff or South Jekyll Island, the average normal sound level is about 39-45db whereas if a person lives in a subdivision aside I-95, the normal is about 79db. Assuming that both locations were the same distance 5 miles from the spaceport, someone in a quiet wooded neighborhood would much more likely to be disturbed. The EPA requirements for a classroom are similar to those of a quiet neighborhood (45db). Of course, Noise Disruption will be much more annoying at night.

An Explosion Is Likely

Explosions are a far more serious Noise Nuisance issue. The 4 mile diameter blast zone at the launch pad is clearly defined where no one can be present, even in a hardened bunker, because of the inherent explosive risk. The calculations used for each launch for the down range Launch Danger Zone (LDZ) take into account the amount of fuel remaining on board at each moment of flight defining the pattern where the debris field might land. That is why the LDZ was typically very wide (22 miles for SpaceX CX40) at the launch pad, narrowing to about 11 miles wide 90 miles at sea. Again, this varies for every launch but these figures are exactly what were required for CX40. The Antares launch accident at Wallops Island in 2014 caused a shock wave that knocked people down at a distance of about 4 miles. There were numerous reports of property damage in an area mostly occupied by chicken houses. This video is very revealing of the actual experience. (See the Video)

HB734 Will Take Away Our Legal Rights

HB734 would permit unlimited rocket engine tests which are not a subject of FAA jurisdiction. In fact, Spaceport Camden could become a rocket engine test site without further FAA approval if actual launch trajectories are too restrictive to be cost effective for spaceport operators. SpaceX tests engines on the average of once per day at its McGregor, Texas test site with nuisance reports coming from 20 miles away.  SpaceX tests engines from early morning to 10pm.

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