Flight Safety Limits Objectives Burden Reducing Clarification

Issuing agencies

Abstract

FAA proposes to amend its commercial space launch and reentry licensing regulations to streamline the licensing process and reduce regulatory burden for license applicants. Specifically, FAA proposes to clarify the requirements for establishing flight safety limits that define when a vehicle operator must initiate flight abort.

Full Text

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<title>Federal Register, Volume 91 Issue 215 (Monday, November 9, 2026)</title>
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[Federal Register Volume 91, Number 215 (Monday, November 9, 2026)]
[Proposed Rules]
[Pages 70821-70824]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-22783]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 450

[Docket No.: FAA-2026- 9937; Notice No. 26-24]
RIN 2120-AM43


Flight Safety Limits Objectives Burden Reducing Clarification

AGENCY: Federal Aviation Administration (FAA), U.S. Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: FAA proposes to amend its commercial space launch and reentry 
licensing regulations to streamline the licensing process and reduce 
regulatory burden for license applicants. Specifically, FAA proposes to 
clarify the requirements for establishing flight safety limits that 
define when a vehicle operator must initiate flight abort.

DATES: Send comments on or before December 9, 2026.

ADDRESSES: Send comments identified by docket number FAA-2026-9937 
using any of the following methods:
    <bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">www.regulations.gov</a> and 
follow the online instructions for sending your comments 
electronically.
    <bullet> Mail: Send comments to Docket Operations; U.S. Department 
of Transportation (DOT), 1200 New Jersey Avenue SE, West Building, 5th 
Floor (W58-213), Washington, DC 20590-0001.
    <bullet> Hand Delivery or Courier: Take comments to Docket 
Operations in Room W58-213 of the West Building, 5th Floor at 1200 New 
Jersey Avenue SE, Washington, DC 20590 between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    <bullet> Fax: Fax comments to Docket Operations at (202) 493-2251.
    Privacy: In accordance with 5 U.S.C. 553(c), DOT solicits comments 
from the public to inform its rulemaking process better. DOT posts 
these comments, without edit, including any personal information the 
commenter provides, to <a href="http://www.regulations.gov">www.regulations.gov</a>, as described in the system 
of records notice (DOT/ALL-14 FDMS), which can be reviewed at 
<a href="http://www.dot.gov/privacy">www.dot.gov/privacy</a>.
    Docket: Background documents or comments received may be read at 
<a href="http://www.regulations.gov">www.regulations.gov</a> at any time. Follow the online instructions for 
accessing the docket or go to the Docket Operations in Room W58-213 of 
the West Building 5th Floor at 1200 New Jersey Avenue SE, Washington, 
DC 20590 between 9 a.m. and 5 p.m., Monday through Friday, except 
Federal holidays.

FOR FURTHER INFORMATION CONTACT: Lisa E. Cacciatore, Office of 
Commercial Space Transportation, Federal Aviation Administration, 1200 
New Jersey Avenue SE, Washington, DC 20590; telephone (202) 880-1489; 
email <a href="/cdn-cgi/l/email-protection#0f43667c6e214a214c6e6c6c666e7b607d6a4f696e6e21686079"><span class="__cf_email__" data-cfemail="6f23061c0e412a412c0e0c0c060e1b001d0a2f090e0e41080019">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION:

I. Overview

    In accordance with Executive Order (E.O.) 14335, ``Enabling 
Competition in the Commercial Space Industry,'' FAA proposes to amend 
its commercial space launch and reentry regulations at 14 CFR part 450 
to further streamline the commercial licensing process. The regulations 
at 14 CFR 450.108(c) require a vehicle operator to determine flight 
safety limits that define when the operator must initiate flight abort. 
To address applicant confusion about the meaning of 14 CFR 
450.108(c)(4), FAA proposes to reword the paragraph to clarify which 
inputs are necessary for establishing flight safety limits to prevent 
high consequence events.

II. Authority for This Rulemaking

    The Commercial Space Launch Act of 1984, as amended and codified at 
51 U.S.C. 50901-50924, authorizes the Secretary of Transportation to 
oversee, license, and regulate commercial launch and reentry 
activities, and the operation of launch and reentry sites within the 
United States or as carried out by U.S. citizens. Section 50905 directs 
the Secretary to exercise this responsibility consistent with public 
health and safety, safety of property, and the national security and 
foreign policy interests of the United States. In addition, section 
50903 requires the Secretary to encourage, facilitate, and promote 
commercial space launches and reentries by the private sector. As 
codified in 49 CFR 1.83(b), the Secretary has delegated authority to 
the FAA Administrator to carry out these functions.

III. Background

    FAA has established commercial space regulations governing 
licensing of launch and reentry in 14 CFR chapter III. On December 10, 
2020, FAA issued a final rule consolidating all substantive launch and 
reentry licensing regulations into a new part 450 (85 FR 79566) that 
went into effect on March 10, 2021.
    On August 13, 2025, the President issued E.O. 14335, ``Enabling 
Competition in the Commercial Space Industry,'' requiring the Secretary 
of Transportation to ``reevaluate, amend, or rescind'' the part 450 
regulations for the purpose of further streamlining the commercial 
licensing process. This proposed rule is being published in furtherance 
of this E.O.
    Section 450.101(c) provides that an operator may use flight abort 
as a hazard control strategy to protect against a high consequence 
event in uncontrolled areas.\1\ Flight abort accomplishes a controlled 
ending to vehicle flight, such as through explosive destruct. Section 
450.108 provides requirements for flight abort, including requirements 
for flight safety limits. Flight safety limits, in this context, define 
the criteria under which a vehicle operator must initiate flight abort.
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    \1\ As defined by 14 CFR 401.7, an ``uncontrolled area'' is ``an 
area of land not controlled by a launch or reentry operator, a 
launch or reentry site operator, an adjacent site operator, or other 
entity by agreement.''
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    One of the requirements for flight abort, located at Sec.  
450.108(c)(4), provides that an operator must determine and use flight 
safety limits defining when the operator must initiate flight abort 
``to prevent conditional expected casualties (CE<INF>C</INF>) greater 
than 1 x 10<SUP>-2</SUP> in uncontrolled areas due to flight abort or 
due to flight outside the limits of a useful mission from any 
reasonably foreseeable off-trajectory failure mode in any significant 
period of flight . . . .'' The purpose of Sec.  450.108(c)(4) is to 
ensure that, when an operator cannot develop flight safety limits that 
prevent hazards from affecting uncontrolled areas, the flight safety 
limits nonetheless protect against

[[Page 70822]]

high consequence events in uncontrolled areas. The paragraph asks 
operators to compute the CE<INF>C</INF> in each significant period of 
flight \2\ where flight abort or flight outside the limits of a useful 
mission \3\ may be an outcome for each reasonably foreseeable off-
trajectory failure mode.\4\ If the maximum CE<INF>C</INF> developed 
through this method is not greater than 1 x 10<SUP>-2</SUP>, an 
operator can demonstrate high consequence event protection. If this 
analysis does not demonstrate compliance with high consequence event 
protection, an operator may modify the limits of a useful mission or 
flight safety limits, and an operator should update the flight safety 
limits analysis accordingly until compliance with Sec.  450.108(c)(4) 
can be demonstrated.
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    \2\ As discussed in the final rule establishing part 450 
``Streamlined Launch and Reentry Requirements'' (85 FR 79566), a 
period of flight is considered significant if it is long enough for 
a mitigation, such as flight abort, to decrease the public risks or 
consequences materially from any reasonably foreseeable failure mode 
(85 FR 79566, 79604).
    \3\ As defined by 14 CFR 401.7, a ``useful mission'' means ``a 
mission that can attain one or more objectives.'' The ``limits of a 
useful mission,'' as defined by that section, means ``the trajectory 
data or other parameters that bound the performance of a useful 
mission, including flight azimuth limits.'' The limits of a useful 
mission are developed as part of the flight safety analysis under 14 
CFR 450.119.
    \4\ As discussed in the final rule establishing part 450 
``Streamlined Launch and Reentry Requirements'' (85 FR 79566), an 
off-trajectory failure is a failure ``for which a vehicle deviates 
from its intended flight path--for example, due to failures of the 
guidance, navigation, or control systems'' (85 FR 79566, 79620). 
Failure modes are categories of hazardous events that share 
significant similarity in cause and system response, prior to 
consideration of mitigations or hazard control strategies. Therefore 
an ``off-trajectory failure mode'' is a failure mode where a vehicle 
deviates from its intended flight path. AC 450.101-1, High 
Consequence Event Protection, provides additional background on 
``failure modes'' and how applicants may identify ``reasonably 
foreseeable'' failure modes.
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    However, the phrasing of paragraph (c)(4) has led some applicants 
to misinterpret the paragraph as requiring two separate CE<INF>C</INF> 
calculations: one for outcomes resulting in flight abort and one for 
outcomes that result in flight outside the limits of a useful mission. 
Meanwhile, other applicants have interpreted the paragraph to mean that 
an applicant may select only one of these two outcomes and ignore the 
other in CE<INF>C</INF> calculations. In AC 450.108-1, Flight Abort 
Rule Development, FAA attempted to clarify the requirement, writing 
that ``[t]he CE<INF>C</INF> results from various end states, such as 
break-up due to aerodynamic loads or FSS activation, from flight abort 
and flight outside the limits of a useful mission should be averaged 
together to compute the mean CE<INF>C</INF> for each significant period 
of flight.'' However, misinterpretations of the rule have persisted and 
led to repeated exchanges with the applicants, requiring additional 
time and effort to develop an acceptable application.

IV. Discussion of the Proposal

    The proposed rule would reword Sec.  450.108(c)(4) to reduce 
confusion among applicants regarding how to comply with the 
requirement. The proposed rule would clarify that the CE<INF>C</INF> 
should be calculated as an average that accounts for both breakup 
states due to flight abort and any outcomes involving flight outside 
the limits of a useful mission--but not breakups within the limits of a 
useful mission--and evaluated against the threshold for each failure 
mode within each significant period of flight. This clarification would 
ensure that both outcomes are combined and accounted for as a single 
CE<INF>C</INF> for each failure mode within each significant period of 
flight.

V. Regulatory Notices and Analyses

A. Regulatory Impact Analysis

    E.O. 12866 (``Regulatory Planning and Review'') and E.O. 13563 
(``Improving Regulation and Regulatory Review'') require agencies to 
regulate in the ``most cost-effective manner,'' to make a ``reasoned 
determination that the benefits of the intended regulation justify its 
costs,'' and to develop regulations that ``impose the least burden on 
society.'' The Office of Management and Budget has determined this 
proposed rule is not a significant regulatory action as defined in 
Section 3(f) of E.O. 12866. FAA is seeking comments on the following 
analysis.
    Currently, 14 CFR 450.108(c) requires a vehicle operator to 
determine flight safety limits that define when the operator must 
initiate flight abort. The proposed rule would reword 14 CFR 
450.108(c)(4) to clarify which inputs are necessary for establishing 
flight safety limits to prevent high consequence events. The current 
wording has caused confusion among vehicle operators, which has 
prompted operators to seek guidance from FAA.
    The analysis first provides an estimate of the cost savings per 
operator. This is a one-time cost savings per operator because they 
would only seek this guidance once. FAA estimates the labor time, per 
operator, to provide this guidance is eight hours for FAA and operators 
each. For FAA, an analyst at a G-Band would complete this work at an 
hourly wage with benefits of $72.80.\5\ This amounts to $582 per 
operator. For an operator, an aerospace engineer would seek this 
guidance from FAA. At an hourly wage rate \6\ with benefits \7\ of 
$96.28, the aerospace engineer cost is $770 per applicant.\8\ Thus, the 
cost savings per operator would be $1,347.
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    \5\ FAA Technical Pay Band, G Band with Washington DC locality; 
effective Jan. 2026, maximum salary of $111,138. The government 
overhead rate is 36.25 percent. This results in the loaded salary of 
$151,426 ($111,138 * 1.3625 = $151,426). The total loaded salary of 
$151,426 is divided by 2,080 hours to get the $72.80 hourly wage. 
2026 FAA Core Compensation Plan Pay Bands, available at: 
<a href="http://www.faa.gov/jobs/working_here/benefits/pay/core_salary_with_conversion.xlsx">www.faa.gov/jobs/working_here/benefits/pay/core_salary_with_conversion.xlsx</a>; Office of Management and Budget, 
Update to Civilian Position Full Fringe Benefit Cost Factor, Federal 
Pay Raise Assumptions, and Inflation Factors Used in OMB Circular 
No. A-76, ``Performance of Commercial Activities'' (Mar. 11, 2008), 
available at: <a href="http://www.whitehouse.gov/wp-content/uploads/legacy_drupal_files/omb/memoranda/2008/m08-13.pdf">www.whitehouse.gov/wp-content/uploads/legacy_drupal_files/omb/memoranda/2008/m08-13.pdf</a>.
    \6\ Bureau of Labor Statistics (BLS), Occupational Employment 
and Wage Statistics--May 2024, Industry: Cross-industry, Private, 
Federal, State, and Local Government, Aerospace Engineers (17-2011), 
available at: <a href="http://data.bls.gov/oes/#/industry/000000">data.bls.gov/oes/#/industry/000000</a>.
    \7\ The total wage includes BLS compensation data. For 2024, BLS 
has wages at 70.5 percent of total compensation, while benefits are 
29.5 percent. See BLS, Employer Costs for Employee Compensation--
December 2024, available at: <a href="http://www.bls.gov/news.release/archives/ecec_03142025.htm">www.bls.gov/news.release/archives/ecec_03142025.htm</a> (Mar. 14, 2025).
    \8\ The hourly salary is $67.88. The total loaded factor is 1.42 
(1/0.705 = 1.42). Therefore, the total overhead wage is $96.28 (1.42 
* $67.88 = $96.28).
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    The cost savings would be minimal because FAA expects there to be 
40 new license applications over the next 5 years. Assuming eight 
applications per year, the total undiscounted cost savings would be 
$53,880. At a seven percent discount rate, the total cost savings would 
be $50,355, and $48,888 at a three percent discount rate.

B. Regulatory Flexibility Act

    Under the Regulatory Flexibility Act (RFA) (5 U.S.C. 601-612), 
agencies must prepare and make available for public comment a 
regulatory flexibility analysis that describes the effect of the 
rulemaking on small entities (i.e., small businesses, small 
organizations, and small government jurisdictions). No regulatory 
flexibility analysis is required, however, if the head of an agency 
certifies that the proposed rule would not have a significant economic 
impact on a substantial number of small entities. FAA has concluded and 
hereby certifies that this proposed rule would not have a significant 
economic impact on a substantial number of small entities; therefore, 
an analysis is not included.

[[Page 70823]]

C. International Trade Impact Assessment

    The Trade Agreements Act of 1979 (Pub. L. 96-39), as amended by the 
Uruguay Round Agreements Act (Pub. L. 103-465), prohibits Federal 
agencies from establishing standards or engaging in related activities 
that create unnecessary obstacles to the foreign commerce of the United 
States. Pursuant to these Acts, the establishment of standards is not 
considered an unnecessary obstacle to the foreign commerce of the 
United States, so long as the standard has a legitimate domestic 
objective, such as the protection of safety, and does not operate in a 
manner that excludes imports that meet this objective. The statute also 
requires consideration of international standards and, where 
appropriate, they be the basis for U.S. standards.
    FAA has assessed the potential effect of this proposed rule and 
determined that it would not create unnecessary obstacles to the 
foreign commerce of the United States.

D. Unfunded Mandates Assessment

    The Unfunded Mandates Reform Act of 1995 (2 U.S.C. 1531-1538) 
governs the issuance of Federal regulations that require unfunded 
mandates. An unfunded mandate is a regulation that requires a State, 
local, or Tribal government or the private sector to incur direct costs 
without the Federal Government having first provided the funds to pay 
those costs. FAA determined the proposed rule would not result in the 
expenditure of $193,000,000 or more ($100,000,000 adjusted for 
inflation using the most current Implicit Price Deflator for the Gross 
Domestic Product) by State, local, or Tribal governments, in the 
aggregate, or the private sector, in any one year.

E. Paperwork Reduction Act

    The Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)) requires 
FAA consider the impact of paperwork and other information collection 
burdens imposed on the public. FAA has determined there would be no new 
requirement for information collection associated with this proposed 
rule.

F. International Compatibility

    In keeping with U.S. obligations under the Convention on 
International Civil Aviation, it is FAA policy to conform to 
International Civil Aviation Organization (ICAO) Standards and 
Recommended Practices to the maximum extent practicable. FAA has 
determined there are no ICAO Standards and Recommended Practices that 
correspond to these proposed regulations.

G. Environmental Analysis

    The Department has analyzed the environmental impacts of this 
notice of proposed rulemaking pursuant to the National Environmental 
Policy Act of 1969 (NEPA) (42 U.S.C. 4321, et seq.). FAA has determined 
this proposed rule is categorically excluded pursuant to FAA Order 
1050.1G. Categorical exclusions are categories of actions FAA has 
determined normally do not significantly affect the quality of the 
human environment and therefore do not require either an environmental 
assessment (EA) or environmental impact statement (EIS). In analyzing 
the applicability of a categorical exclusion, FAA must also consider 
whether extraordinary circumstances are present that would warrant the 
preparation of an EA or EIS. This rulemaking, which would clarify the 
requirements for establishing flight safety limits that define when a 
vehicle operator must initiate flight abort, is categorically excluded 
pursuant to FAA Order 1050.1G, Appendix B, Paragraph B-2.6(f), which 
categorically excludes issuance of regulatory documents. FAA does not 
anticipate any environmental impacts, and there are no extraordinary 
circumstances present in connection with this rulemaking.

VI. E.O. Determinations

A. E.O. 13132, Federalism

    FAA has analyzed this proposed rule under the principles and 
criteria of E.O. 13132, Federalism. FAA has determined this action 
would not have a substantial direct effect on the States, or the 
relationship between the Federal Government and the States, or on the 
distribution of power and responsibilities among the various levels of 
government, and, therefore, would not have federalism implications.

B. E.O. 13175, Consultation and Coordination With Indian Tribal 
Governments

    Consistent with E.O. 13175, Consultation and Coordination with 
Indian Tribal Governments,\9\ and FAA Order 1210.20, American Indian 
and Alaska Native Tribal Consultation Policy and Procedures,\10\ FAA 
ensures Federally Recognized Tribes (Tribes) are given the opportunity 
to provide meaningful and timely input regarding proposed Federal 
actions that have the potential to affect uniquely or significantly 
their respective Tribes. At this point, FAA has not identified any 
unique or significant effects, environmental or otherwise, on Tribes 
resulting from this proposed rule.
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    \9\ 65 FR 67249 (November 6, 2000).
    \10\ FAA Order No. 1210.20 (January 28, 2004), available at 
<a href="http://www.faa.gov/documentLibrary/media/1210.pdf">www.faa.gov/documentLibrary/media/1210.pdf</a>.
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C. E.O. 13211, Regulations That Significantly Affect Energy Supply, 
Distribution, or Use

    FAA analyzed this proposed rule under E.O. 13211, Actions 
Concerning Regulations that Significantly Affect Energy Supply, 
Distribution, or Use (May 18, 2001). FAA has determined it would not be 
a ``significant energy action'' under the E.O. and would not be likely 
to have a significant adverse effect on the supply, distribution, or 
use of energy.

D. E.O. 13609, Promoting International Regulatory Cooperation

    E.O. 13609, Promoting International Regulatory Cooperation, 
promotes international regulatory cooperation to (1) meet shared 
challenges involving health, safety, labor, security, environmental, 
and other issues and to reduce, eliminate, or (2) prevent unnecessary 
differences in regulatory requirements. FAA has analyzed this action 
under the policies and agency responsibilities of E.O.13609 and has 
determined this action would have no effect on international regulatory 
cooperation.

E. E.O. 14192, Unleashing Prosperity Through Deregulation

    This proposed rule, if finalized as proposed, is expected to be an 
E.O. 14192 deregulatory action.

VII. Additional Information

A. Comments Invited

    FAA invites interested persons to participate in this rulemaking by 
submitting written comments, data, or views. FAA also invites comments 
relating to the economic, environmental, or federalism impacts that 
might result from adopting the proposals in this document. The most 
helpful comments reference a specific portion of the proposal, explain 
the reason for any recommended change, and include supporting data. To 
ensure the docket does not contain duplicate comments, commenters 
should submit only one time if comments are filed electronically, or 
commenters should send only one copy of written comments if comments 
are filed in writing.
    FAA will file in the docket all comments it receives, as well as a 
report summarizing each substantive public contact with FAA personnel 
concerning

[[Page 70824]]

this proposed rule. Before acting on this proposal, FAA will consider 
all comments it receives on or before the closing date for comments. 
FAA will consider comments filed after the comment period has closed if 
it is possible to do so without incurring expense or delay. FAA may 
change this proposal in light of the comments it receives.

B. Confidential Business Information

    Confidential Business Information (CBI) is commercial or financial 
information that is both customarily and actually treated as private by 
its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), 
CBI is exempt from public disclosure. If your comments responsive to 
this NPRM contain commercial or financial information that is 
customarily treated as private, that you actually treat as private, and 
is relevant or responsive to this NPRM, it is important you clearly 
designate the submitted comments as CBI. Please mark each page of your 
submission containing CBI as ``PROPIN.'' FAA will treat such marked 
submissions as confidential under the FOIA, and they will not be placed 
in the public docket of this NPRM. Submissions containing CBI should be 
sent to the person in the FOR FURTHER INFORMATION CONTACT section of 
this document. Any commentary FAA receives that is not specifically 
designated as CBI will be placed in the public docket for this 
rulemaking.

C. Electronic Access and Filing

    A copy of this NPRM, all comments received, any final rule, and all 
background material may be viewed online at <a href="http://www.regulations.gov">www.regulations.gov</a> using 
the docket number listed above. Electronic retrieval help and 
guidelines are available on the website. It is available 24 hours each 
day, 365 days each year. An electronic copy of this document may also 
be downloaded from the Office of the Federal Register's website at 
<a href="http://www.federalregister.gov">www.federalregister.gov</a> and the Government Publishing Office's website 
at <a href="http://www.govinfo.gov">www.govinfo.gov</a>. A copy may also be found at FAA's Regulations and 
Policies website at <a href="http://www.faa.gov/regulations_policies">www.faa.gov/regulations_policies</a>.
    Copies may also be obtained by sending a request to the Federal 
Aviation Administration, Office of Rulemaking, ARM-1, 800 Independence 
Avenue SW, Washington, DC 20591, or by calling (202) 267-9677. 
Requesters must identify the docket or notice number of this 
rulemaking.
    All documents FAA considered in developing this proposed rule, 
including economic analyses and technical reports, may be accessed in 
the electronic docket for this rulemaking.

D. Small Business Regulatory Enforcement Fairness Act

    The Small Business Regulatory Enforcement Fairness Act of 1996 
(Pub. L. 104-121, 110 Stat. 857, Mar. 29, 1996) requires FAA to comply 
with small entity requests for information or advice about compliance 
with statutes and regulations within its jurisdiction. A small entity 
with questions regarding this document may contact its local FAA 
official or the person listed under the FOR FURTHER INFORMATION CONTACT 
heading at the beginning of the preamble. To find out more about SBREFA 
on the internet, visit <a href="http://www.faa.gov/regulations_policies/rulemaking/sbre_act/">www.faa.gov/regulations_policies/rulemaking/sbre_act/</a>.

List of Subjects in 14 CFR Part 450

    Aircraft, Aviation safety, Environmental protection, 
Investigations, Reporting and recordkeeping requirements, Space 
transportation and exploration.

The Proposed Amendments

    For the reasons discussed in the preamble, the Federal Aviation 
Administration proposes to amend chapter III of title 14, Code of 
Federal Regulations, as follows:

PART 450--LAUNCH AND REENTRY LICENSE REQUIREMENTS

0
1. The authority citation for part 450 is revised to read as follows:

    Authority:  51 U.S.C. Chapter 509.

0
2. Revise Sec.  450.108(c)(4) to read as follows:


Sec.  450.108  Flight abort.

* * * * *
    (c) * * *
    (4) To prevent conditional expected casualties in uncontrolled 
areas, averaged over outcomes that result in either flight abort or 
flight outside the limits of a useful mission, greater than 1 x 10 
<SUP>-2</SUP> from any reasonably foreseeable off-trajectory failure 
mode in any significant period of flight; and
* * * * *

    Issued under authority provided by 49 U.S.C. 106(f) and 51 
U.S.C. chapter 509 in Washington, DC.
Anh Minh Ngoc Nguyen,
Deputy Associate Administrator, Office of Commercial Space 
Transportation.
[FR Doc. 2026-22783 Filed 11-6-26; 8:45 am]
BILLING CODE 4910-13-P


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