Docket Operations M-30 

U.S. Department of Transportation 

1200 New Jersey Ave. SE 

Room W12-140 

West Building Ground Floor 

Washington, DC 20590-0001 

Subject: DOCKET# FAA-2014-0418 

To Whom It May Concern: 

October 20, 2014 \_ ., . :-;. 

Space Exploration Technologies Corp. (SpaceX) respectfully submits our comments in 

response to the Federal Aviation Administration's (FAA) Notice ofProposed 

Rulernaking (NPRM), Changing the Collective Risk Limits for Launches and Reentries 

and ClarifYing the Risk Limit Used to Establish Hazard Areas for Ships and Aircraft, 

published in the Federal Register on July 21, 2014. 

1. Launch Risk Limits of an EL V 

Spac,eX. support~ the proposed rulemaking that will aggregate the launch hazards and amend 14 

CFR § 417.107(b)(1). Since the overarching concern is with public safety, the FAA proposes tb 

amend the regulation to focus on the collective risk and an aggregate.Ec. As the FAA discusses 

in the NPRM, the proposed change will eliminate the; inconsistencies· that result from the current 

regulation, while m1:1,intaining an appropriate focus on overall public safety. 

SpaceX also appre~ia.tes . the opportunity to express it~ support for making the FAA's Ec 

requirements consistent.with other U.S. Government standards. The FANs proposed Ec value of 

Ec :S 1 x 10-4 is consistent with the Ec currently used in U.S. Government Orbital Debris 

Mitigation Standard Practices, Range Commanders Council Document 321 10 (Common Risk 

Criteria for National Test Ranges), Air Force Instruction 91-217 (2010 Space Safety and Mishap 

Prevention Program), and NASA Technical Standard NASA-STD 8719.14 (Process for Limiting 

Orbital Debris). Thus, the proposed rulemaking to reguire Ec:S 1. x w'-4 will provide consistency . • • ' i' • . ,. • 

2. Risk Limits of Reentry License 

SpaceX supports the change. that the FAA;s proposed rulemaking will make to 14 CFR § 435.35 

by eliminating the "combined" Ec. requirement for launch and reentry and separating the Ec 

calculations into two di.screte events: launch and reentry. SpaceX believes· it is more logical to . . . 

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routinely separate launch from reentry risk since the two events are distinct. This replicates the 

approach taken by the U.S. Air Force, which, as discussed in the NPRM, imposes a requirement 

of Ec ::; 100 x 10-6 on launch and a separate requirement @f Ec ::;, 100 x 10-9 on r~entry per Air 

Force Instruction 91-+J 7 (2010 Space _Safety and Mishap ,PreveJ;ltion Progr~m); This logically 

consistent methodology also would eliminate some of the potential infelicities that may result 

from combining launch and r~entry risk Jlnder the F AA:s current approach. Accordingly, SpaceX 

'supports tha~ the FAA propose,d rulemaking to-treat l~~nch <J.nd reentry risk se,.parat~ly; it is both a 

more logical approach to the·"subject and· consistent' with the approach tak.en by the U.S. Air 

Force. · . . . ' . 

SpaceX also supports the FAA's proposed changes to 14 CFR § 43(35(b)(l)(i) to adopt an Ec 

value of Ec::; 1 x 10-4

, which is consistent with the Ec used in U.S. Government Orbital Debris 

Mitigation Standard Practices, Range Commanders Council Document 321 10 (Common Risk 

Criteria for National Test Ranges), Air Force Instruction 91-217 (2010 Space Safety and Mishap 

Prevention Program), and NASA Technical Standard NASA-STD 8719.14 (Process for Limiting 

Orbital Debris). As with the risk limit for launch, the FAA's proposed rulemaking to require Ec :S 

1 x 10-4 for reentry will provide consistency. 

Conclusion • 

For the reasons set forth above, SpaceX strongly supports the FAA proposed rulemakitig 

to separate its expected number of casualties (Ec) limits for launches and reentries and its 

changes to the Ec limit for each. SpaceX believes the proposed rulemaking is in the 

public interest and will not jeopardize ptibli~ h,e~lth and safety, the safety or property, or 

any nat~ona~security or foreigfl 'po,licy'interest ofth~ United Stat~s. · •. , . 

Thank you for taking the time to' consid~ring our views on this issue .. Please contact me 

at 202-649-2704 (tim.hughes@spacex.com), or Caryn Schenewerk · (202~649-2707; 

caryn@.spacex.com) with any questions or concerns .. 

Sincerely, n:: c.__,........-· ~--- -~::;f- ~- yc...-- --~ 71// /"' .. e:: ~~~ /.d. 

/ ... ~-~·c' 

Timothy R. ug es 

SVP & General Counsel