White Paper: About Launch Hazard Zones
Camden County's spaceport subject matter consultant has used MARS Spaceport at Wallops Island, Virginia to explain why nearby residences are not evacuated for launches and therefore, why Camden residents should not be concerned. This document demonstrates why the Wallops example is not accurate and also why it is not relevant to Camden County and to help you understand how the FAA determines the required Launch Hazard Zones that will apply to Spaceport Camden.
Camden's expert has claimed that homes within the Launch Hazard Zone (called the Accident Potential Zones at Wallops Spaceport) are not evacuated during rocket launches.
In fact, NASA states that there are no residences in the mandatory evacuation zones that are established at Wallops Spaceport. Only the free-standing garage of a single private residence is located in the mandatory evacuation Launch Hazard Area for Wallops’ MARS Spaceport's launchpad for smaller sub-orbital rockets. That home is outside the mandatory evacuation zones for the larger rockets Camden is proposing. A review of property tax records indicates the only buildings in the mandatory evacuation zones are agricultural sheds, a dilapidated, unoccupied home, and structures on property owned by the spaceport, not private parties.
Here are the facts: Wallops MARS spaceport is located on the oceanfront and includes 3 Launch Hazard Zones that are concentric to the two existing and one proposed launch pads. The immediate Blast Hazard Zone (called a “Clear Zone”) around the rocket is typically about 2,000 feet or so in diameter, depending on the rocket being launched. Extending 10,000 feet (1.89 miles) from the launch pad is Accident Potential Zone 1 (“APZ-1”) which is subject to mandatory evacuation on launch days. There are no residences within APZ-1 and no launch spectators are allowed within this zone. APZ-2 extends for another 10,000 feet (total of 20,000 feet or 3.78 miles) from the launch pad, but is only partially evacuated depending on the weather conditions and mission-specific safety calculations. There are private properties and about 100 residences in APZ-2, but typically these owners are told to not gather large crowds, and "to stay indoors", "away from windows" to avoid broken glass and "possible toxic fumes".
An inventory of all property was conducted in 2014 and 2015 to determine the extent of risk exposure. NASA Field-Verified all structures within the Hazard Zones. Contrary to Camden County's statements, as these extracts from extensive tables in the 2015 Accomack, Va. Joint Land Use Study, NASA verified that there are no residential properties within the mandatory 10,000 foot evacuation zone at Wallops Island MARS Spaceport. In fact, due to their smaller size and eastward trajectories, all of the Orbital ATK Antares rockets ever launched from MARS have had smaller mission- specific 8,500 or 9,000 foot evacuation zones.
WALLOPS IS OCEANFRONT - SPACEPORT CAMDEN IS NOT
Wallops spaceport is located directly on the ocean and launches directly over the ocean. Even their launch launch noise is directed by a concrete trench towards the ocean. Obviously, there are no residences in the ocean. A rocket cannot fly over homes unless it is headed the wrong way.
Confusingly, Camden County mixes the proverbial apples with the oranges. The “Clear Zone” near the launch pad and APZ-1 Zones cover the part of the Launch Hazard Area that are always cleared of non-mission personnel. Additional areas may be cleared behind the launch pad if weather conditions require but that has never been required at Wallops MARS Spaceport.
Spaceport Camden will have the similar restricted zones which will lie entirely on spaceport property. What Camden's consultants fail to address is the Launch Hazard Area that lies under the flight corridor of the rocket and within the blast debris hazard zones that are established for each mission along the flight corridor.
CUMBERLAND WILL BE UNDER HAZARD ZONES
Spaceport Camden, unlike any other US rocket spaceport, is located more than 6.8 miles from the nearest oceanfront. Residences, private property and Cumberland Island National Seashore ARE directly under the flight path of any possible trajectory from Spaceport Camden. These properties will be subject to the rocket explosion that Camden's Mr. Nelson assures us will statistically happen from our spaceport once every 8 years or so.
The Cumberland Island Wilderness Area is indicated by red Boundary Lines. The Wilderness Area is legally protected by the most restrictive Conservation Covenants in the USA. The combined red and yellow shaded areas represent the likely Launch Danger Zone assigned to Spaceport Camden launches.
Virtually 100% of the Wilderness Area would be contained within the Launch Danger Zone for any launch trajectory from Spaceport Camden. The shaded area represents the minimum hazard zone assigned for the direct-over-ocean launches from Kennedy/Canaveral for medium-lift rockets from 2013 to 2016 and should be representative of the minimum hazard zone that will be assigned to Spaceport Camden launches.
Wilderness Areas are so highly restricted that Congressman Jack Kingston had to sponsor a new Federal law to allow a 25' right-of-way along the existing unpaved Main Road permitting commercial tourist vans to travel through the Wilderness Area to National Seashore historic sites on the North End. The Wilderness Act forbids mechanical intrusions into Wilderness; for instance, it is illegal to ride a bicycle on any trail in the Wilderness Area. There is existing precedent. Rocket launches have never been allowed over Assateague Island National Seashore from Wallops Flight Center in Virginia. Assateague has lower conservation protection requirements than does Cumberland’s Wilderness.
The Proposed Trajectory is also the southern-most trajectory possible from Spaceport Camden due to restrictions preventing launches over populated land and proximity to Kings Bay Naval Submarine Base. All launches from Spaceport Camden will include private property and residences on Little Cumberland and Cumberland Islands in the Launch Danger Zone. Rocket launches impacting third party private property have never been allowed by the FAA against the owner's wishes.
The yellow shaded area north of the Wilderness is part of the Launch Danger Zone encompassing National Seashore and private property and residences on Little Cumberland Island. Both the red and yellow zones, including the Intercoastal Waterway and extending at least 3 miles offshore will require evacuation to comply with mandated FAA safety rules that are in place at all other spaceports. (The example illustrated is produced by overlaying Spaceport Camden with a typical launch hazard zone from actual Kennedy Canaveral launches.)
HOW LAUNCH CORRIDORS ARE CALCULATED
Kennedy, Canaveral, Vandenberg, Wallops, Boca Chica and Kodiak spaceports (and eventually at Spaceport Camden) apply the safety calculations that are summarized in drawing (Figure B-1) found in the FAA Part 420, Appendix B Manual explaining how the Rocket Flight Corridor is calculated:
For each second of flight(“i”) a calculation is made that considers the explosive risk and potential for drifting off trajectory of the rocket. A circle of “D” diameter is drawn that represents the possible spread of debris from an exploding rocket. A circle is drawn at the Distances “X” for each second the rocket is planned to move down the range. Several hundred circles are required for the minutes that the rocket is moving beyond the range.
As the rocket gains altitude and proceeds downrange, the circles get larger because the possible debris field increases. Then, as fuel is used up, the circles become smaller until the spent rocket stage crashes into the ocean hundreds of miles down range. A complete analysis includes the splashdown zone for the second stage that is frequently in the Indian Ocean. And if the 1st stage is being returned to the spaceport for recovery, a similar hazard analysis is conducted and its exclusion zone added to the total hazard zone picture.
Of course, the calculations are far more complicated than we’ve explained here because the payload, intended orbit, weather conditions at the moment of launch, and a myriad of other factors are also factored in because “launching rockets is still an incredibly dangerous business,” said Dr. David Baker, a former NASA engineer, after the 2014 Antares explosion at Wallops MARS Spaceport.
ABOUT CONFIDENCE IN RISK PROJECTIONS
All of the calculations must consider the reliability of the rocket being launched. Attempting to use historic averages for all rockets that have ever launched is misleading when considering the risk from a specific launch. Mark Twain is famously quoted saying, “There are lies, damned lies, and statistics.” There was even a book entitled, “How to Lie with Statistics” by Darrell Huff. Our purpose here is to show you how Camden’s own statistics must be properly interpreted to be factually correct in the way the FAA will use similar numbers.
The following is quoted from “Hazard Analysis of Commercial Space Transportation”, FAA: “Tests to establish reliability of complex components or systems are usually expensive, making a minimum of tests desirable. On the other hand, true probabilities are based ideally on results from very large samples. When only a few items are tested, the results may not be truly representative. Tossing a normal coin two or three times may result in heads each time. This may lead to the erroneous assumption that the result will always be heads. The next three tosses may all be heads again, all tails or combinations of heads or tails. With more and more tests the average probability of a head (or tail) will be found to approach 0.5. The problem then arises as to how much confidence can be placed on past results to predict future performance. The term confidence level is used for this purpose. Tables have been prepared to indicate the relationships between test results, reliability and confidence. One such table is shown below in abbreviated form (Table 8-4). Since there are residual uncertainties associated with the quantification of risk, confidence limits must be placed both on failure probabilities (usually 60%-90% brackets) to reflect this uncertainty.””
Camden’s expert has said that there has been only a 0.99% chance of an explosive, inflight accident in the history of rocket launches. He implies that rockets are 99.1% reliable. That is not how the FAA looks at launch risk. Using the same ‘facts’ and FAA methodology, there would have to have been over 460 launches WITHOUT A FAILURE to have 99% confidence that an explosive accident will not occur over Camden 99% of the time. Since the Camden sample had only 300 or so selected launches, and the explosive accidents have been interspersed throughout that number, it is statistically impossible to have a confidence level higher than 94% (95% times 99%) that such an accident will not occur over Camden County. But the probability would only be as high as 94% if there had not been a rocket explosion in 299 straight launches. Actually, there have been fewer than 35 US launches since the last in-flight explosion of SpaceX CRS-8 on June 28, 2015, so the maximum confidence that an explosion will not occur on the next launch is 84% using FAA methods. And based on recent history our confidence can only be 50% when we count the September 1, 2016 launch pad explosion of the SpaceX Amos-3 mission.
(Each of the above numbers will change based on the total number of launches and explosion events conducted after 11/08/2016.)
Meaningful confidence calculations can only be made based on the specific safety history of the specific model
and configuration of rocket being launched. Even if Camden's argument were accurate in its rocket explosion count,
it's methodology and conclusions about the risk to Camden County are not.
The FLIGHT CORRIDOR NEAR A SPACEPORT
A different representation of the Rocket Flight Corridor and Launch Hazard Zones is explained in illustration Figure 9-4 taken from the Vandenberg spaceport Range Safety Handbook.
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The Trajectory is shown as an orange line.
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The Debris Pattern Envelopes (reference B-1 above) are shown as circles. They are not in a straight line because they are calculated taking prevailing winds into account.
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The Impact Limit Line is yellow. It represents the endge of the area where any explosion debris can be allowed to fall due to the danger to humans and private property.
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The red line is the Destruct Line. If an errant rocket goes off course, it must be destroyed if it crosses this line to prevent damage beyond the Impact Limit Line.
In the example shown, if a rocket is at Present Position and fails intact (for instance, the motors stop) the Intact Vehicle will impact in the small rectangular box shown. If the rocket were to explode at Present Position, then the Debris Pattern Circles would apply at that moment.
In every case, the hazard zones expand dramatically as the rocket moves down range and gains altitude. This is shown by the widening Impact Limit Lines. The evacuation zones are based on mission-specific calculations and cannot be lumped into a single representation such as that regularly shown by Camden officials and agents.
REAL SPACEPORT HAZARD ZONES
What actually happens is that in cooperation with the Coast Guard and range management, practical and repeatable exclusion areas are determined for each spaceport and these are entered into the Federal Register under 33 CFR. None of the existing spaceport ranges has a range safety zone that looks like what Camden shows.
CANAVERAL COMBINED HAZARD ZONES
Here is a typical closure map for Kennedy/Canaveral (SpaceX Falcon 9 Mission Amos-6. This was the mission that exploded on the launch pad on September 1, 2016):
In addition to the launch pad hazard zones, three downrange zones were required for this launch.
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The red outline shows the Coast Guard controlled zone to the 3 mile limit offshore. The equivalent for Camden would be 3 miles into the Atlantic off Cumberland’s and Jekyll’s beaches. The red zone extends from Port Canaveral to Playalinda Beach, a distance of about 20 miles as the crow flies.
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The black outlined area represents 33 CFR 165.701 which is the launch hazard zone assigned for this mission. This zone is about 6 miles wide at the launch pad, extending about 42 miles down range where the zone expands to about 10 miles wide. At both Wallops and Kennedy, launches have been recently scrubbed in the final minutes because single boats entered the 33 CFR exclusion zones.
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The Green Zone is a mission specific hazard zone required for the returning 1st stage for landing at Cape Canaveral.
Click a button on the left for additional examples of Kennedy/Canaveral Launch Hazard Zones.
WALLOPS COMBINED HAZARD ZONES
Wallops MARS spaceport has multiple hazard exclusion zones that surround the launch pad and down range hazard areas.
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the launch pad “Clear Zone”, mandatory evacuation
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APZ-1, 10,000 Arc, , mandatory evacuation
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APZ-2, 20,000' Arc, selective restrictions
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33 CFR 334.130 (“33CFR”), mandatory evacuation. According to the U.S. Army Corps of Engineers, 33CFR334.130 is “necessary to protect the public from hazards associated with rocket-launching operations.” 33CFR334.130 extends 34 miles offshore, is 52 miles wide and covers almost 1,170 square miles of restricted land and ocean.
CAMDEN, WHAT EXACTLY HAVE YOU BEEN SHOWING US?
Camden has been working on its spaceport since at least 2012. Hundreds of thousands of dollars have been spent on consultants. More than $3 million in total has been spent with millions more due. So what is it that Camden County has been showing us about the hazard zones? It certainly is not an accurate interpretation of the rules required by the FAA, Air Force or the Code of Federal Rules. In fact, we don't even know what rocket will launch so everything they show is speculative.
Camden County continues to show a downrange hazard area that is rectangular and remains the same width from near the launch pad, over Cumberland Island and far downrange. The hazard zone does not appear to be the result of actual calculations representative of the FAA’s methodology for determining rocket flight corridors and hazard zones.
Two of the various diagrams provided by Camden County showing the proposed launch trajectory.
WHY THE FLIGHT CORRIDOR MATTERS
Every existing rocket spaceport in the US launches its rockets directly over the ocean. Spaceport Camden cannot.
As Camden County's Mr. Nelson has convincingly explained, an explosive accident after launch is statistically likely in almost 1% of launches. [On September 22, 2016, in the Tribune-Georgian, Mr. Nelson, Camden County's spaceport subject matter expert stated, "It is clear that the current United States active vertical orbital launcher fleet is very robust, with a launch success rate of approximately 99 percent"] Since Camden will be licensed for 12 launches per year, that means that sometime during each 8.3 years, an explosion would occur after a launch from Spaceport Camden. It could be the first launch, the 10th launch, or the hundredth launch. All of the safety precautions are in place BECAUSE accidents are expected.
Mr. Nelson also assumes that rockets launched from Camden will come from the existing, mature rocket fleet. Camden officials have claimed no "partner" for their public/private partnership. There are indisputably sufficient launch pads at numerous launch sites for the rockets Mr. Nelson used in his highly qualified risk analysis. It is far more likely that Camden will only be in demand by wanna-be rocket companies that at this point do not have a single successful launch between them. Their safety record must still be proven.
Irrespective of which rocket ultimately fires from Camden, by launching over private property, residences, the Cumberland National Seashore and Wilderness Area significant risks are increased when a rocket fails during launch. Whereas the launch pad area will be cleared of anything that could burn, Cumberland and Little Cumberland are covered with a rare and valuable climax Maritime Forest, the largest such forest on the Atlantic Coast. A rocket explosion over Cumberland’s forests could be catastrophic since such a fire could not be successfully fought. There is no fire station of fire hydrants on Little Cumberland Island. Cumberland and Little Cumberland together have more than 100 private properties, 45 private homes, numerous historical structures, a National Wilderness Area and tourism, none of which are not found down range at any other spaceport.
Two explosive accidents show that the most feared accident has happened before in the United States: A SpaceX rocket launched from Kennedy Space Center on June 28, 2015 ended in an explosion just two minutes down range; and a ULA Titan IV missile exploded a minute after launch from Vandenberg AFB. Had that launch taken place from Spaceport Camden, the exploding rocket would have landed entirely on Cumberland Island. Both accidents resulted in expensive but relatively harmless incidents because those spaceports launch directly over the ocean. The same accidents over Camden County would be catastrophic.
There is a significant economic problem that Spaceport Camden will face. All commercial rocket launches are required by the FAA to have sufficient insurance to cover the possible loss should an explosion occur. This amounts to millions of dollars of coverage for a single launch, even over the ocean. At all other spaceports, the risks found at Spaceport Camden simply don't exist because they launch directly over the ocean. The insurance companies and range operating rules currently stop launches if a single boat is down range. Because of the increased risks to Cumberland, Little Cumberland and Jekyll Islands, insurance costs will be much higher at Spaceport Camden and will be an economic barrier when launch companies have a choice of spaceports.