LAX Part 161 Study

Frequently Asked Questions

What is a FAR Part 161 Study?  

A Federal Aviation Regulations (FAR) Part 161 Study, Notice and Approval of Airport Noise and Access Restrictions, is a comprehensive technical and legal analysis that airports must perform when proposing any noise or operational access restrictions on aircraft at an airport. The Study process must include: (1) public notification; (2) opportunity for public input; (3) scientific study of the noise environment; (4) a benefit-cost analysis of the proposed restriction and (5) a federally determined documentation process. The product of the Study is an application to the Federal Aviation Administration (FAA) requesting waiver of the federal preemption of local airport noise and access restrictions and authorization to enact and implement the proposed restriction.  

The FAR Part 161 Study being conducted at Los Angeles International Airport (LAX) seeks to restrict easterly takeoffs between the hours of midnight and 6:30 a.m. whenever LAX is in Over Ocean-Operations or when it remains in Westerly Operations during these hours (this is the LAX Proposed Restriction).  

Furthermore, Part 161 requires that an airport proprietor study the impacts of a proposed noise or access restriction within a specific area. That area must include all property that lies within the zone that shows average noise levels exceeding 65 decibels CNEL. In determining whether land uses around the airport will benefit from the proposed rule, land uses must be evaluated using compatibility guidelines defined in FAR Part 150, Airport Noise Compatibility Planning.  

Only when the FAA has approved the Part 161 Study, can the airport implement the proposed restriction.  


Who conducted the FAR Part 161 Study at LAX and what was involved?  

Los Angeles World Airports (LAWA) conducted the FAR Part 161 Study at LAX. LAWA contracted with the consulting firm, Harris Miller Miller & Hanson Inc., (HMMH) of Burlington, MA. HMMH is the only consulting firm to have successfully conducted a FAR Part 161 Study that was approved by the FAA, the federal agency responsible for the coordination of all domestic airport operations, and has the sole authority to approve or disapprove of Part 161 studies.

In addition, there were several subcontractors that assisted with certain parts of the study. Subcontractors involved in the LAX FAR Part 161 study included professionals who performed air traffic control analyses, economic benefit-cost analyses, land use planning analysis, and public outreach. The study began in the Summer of 2005 and, following delays associated with the development of the baseline and five-year forecasts of aircraft operations at LAX, was completed in December 2012. The LAX Part 161 Study application was submitted to the FAA for review at the end of January 2013.  


Why was conducting the FAR Part 161 Study important?  

The FAR Part 161 study was important because it will determine if LAX can reduce the number of certain specified flights and their resulting noise levels in communities designated in the study zone near the airport. The LAX Part 161 Study, if approved by the FAA, would allow the City of Los Angeles to restrict easterly departures between the hours of midnight and 6:30 a.m. when LAX operates in Over-Ocean Operations or remains in Westerly Operations during these hours.  The Part 161 Study is the process required by the FAA in order for an airport to implement a proposed restriction, should the findings of the study indicate that the restriction is feasible and fulfills mandated guidelines.

The process of proposing a new restriction has three principal elements:

  • Collecting data and providing analyses to justify the restriction and to explain its environmental and economic impact
  • Notifying the public and allowing time for comment on the proposed restriction
  • Submitting the restriction and its related documentation for FAA review and approval


What is the goal of the FAR Part 161 Study?

The goal of the FAR Part 161 Study at LAX is to restrict eastbound departures between the hours of midnight and 6:30 a.m. daily (except for those days/times when LAX operates in Easterly Operations). The proposed restriction, if approved by the FAA, would reduce aircraft noise affecting communities surrounding LAX during the specified time period, excluding those aircraft exempted from the restriction (for example, military aircraft; medical/mercy or life flights; and government owned/operated aircraft involved in law enforcement, fire fighting and search & rescue operations, or other emergency operations).

The Airport Noise and Capacity Act of 1990 and the Part 161 regulations requires that LAWA collect substantial evidence to prove to the FAA that:

  1. The proposed restriction is reasonable, non-arbitrary, and nondiscriminatory
  2. The proposed restriction would not create an unreasonable burden on interstate or foreign commerce
  3. The proposed restriction would maintain safe and efficient use of navigable airspace
  4. The proposed restriction would not conflict with any existing federal statute or regulation
  5. Los Angeles World Airports has provided adequate opportunity for public comment
  6. The proposed restriction does not create an unreasonable burden on the national aviation system.


How will the study affect noise at LAX?  

There are numerous factors that influence aircraft noise levels over communities, such as the age of the aircraft, engine type and power settings, the aircraft's altitude, direction of flight, and wind & weather conditions.

If the proposed restriction is approved by the FAA, LAWA will submit the proposed ordinance to the LAWA Board of Airport Commissioners and the City Council. After the ordinance is enacted by City Council, LAWA will be able to implement the proposed restriction. This means the noise produced by non-conforming easterly departures between the hours of midnight and 6:30 a.m., when other aircraft are able to take off over the ocean, would be reduced by limiting the number of flights that depart to the east. 

Exemptions to this restriction include: emergency aircraft on fire and rescue missions, military and national security operations, law enforcement and other government owned or operated aircraft, and medical/mercy operations. East departures that occur during Easterly Operations are also exempt from the proposed restriction.

If violations occur, fines would be imposed on the violating airlines.


What are the benefits of the study to the affected communities?  

An FAA-approved study will provide communities with some late night/early morning noise relief by reducing the number of aircraft departing from LAX to the east over communities. This means residents will not be as frequently disturbed by noise from these takeoffs between midnight and 6:30 a.m. The current number of annual disturbances by these flights would be expected to decrease.

What role will community residents play in the study?  

Community residents will have the opportunity to provide comments regarding the impacts of nighttime flights and communicate their opinions regarding the proposed restriction once the FAA opens a public comment docket. More importantly, because this study was conducted largely for the benefit of the community, resident participation is important to the success of the study. Public comments submitted to the FAA will help provide necessary evidence of the impacts of noise on affected residents and communities.

What roles will Los Angeles World Airports (LAWA) and the Federal Aviation Administration (FAA) play in this study?  

LAWA is responsible for conducting the study and implementing the restriction, if approved. The FAA maintains the ultimate authority to approve or deny the proposed restriction.

In order for LAWA to submit the application for the proposed restriction to FAA for review, the FAR Part 161 regulations require that the study must first comply with these three main elements:

  • Collection of data to justify the restriction
  • Public notification and allowance for public comment
  • Submittal of the proposed restriction to the FAA for review and approval.

The final authority to approve or deny the findings rests with the FAA, which has up to 180 days to review the application. If the FAA deems that the findings are relevant and meet the six statutory conditions established in ANCA, the proposed restriction may be approved. If approved, the rule would take effect upon enactment of any airport rules and regulations by the Board of Airport Commissioners and/or an enabling ordinance by the Los Angeles City Council.


What are the penalties for violations?  

If an aircraft violates the Proposed Restriction (if the study is approved by FAA) LAWA staff would prepare a case and present it to the Office of the City Attorney for an enforcement action. The penalties for violations of the LAX proposed restriction are listed in SECTION 7 of the Draft Ordinance, which is contained in the Part 161 Study application. The proposed penalties are a $2,500 fine for the first violation; a $5,000 fine for a second violation within a year of the first violation; and a $10,000 fine for a third (and all subsequent violations) within three years of the first violation.  

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