Project Background

The FAA is proposing to introduce a new instrument approach procedure (IAP) to Runway 4L at Boston Logan International Airport (BOS). This new procedure, referred to as the RNAV (GPS) RWY 4L procedure, will provide enhanced safety for aircraft approaching Runway 4L as well as the ability for BOS to operate more efficiently under poor weather conditions.

FAA has included a video that provides a brief overview of the proposed new procedure to Runway 4L at BOS. The video provides information on the layout of BOS and the anticipated path of the procedure, including animations of charted waypoints and transitions to Runway 4L. The video discusses the projected annual 359 flights that will use the proposed new procedure. These 359 annual flights represent 104 operations reallocated from other arrival runways and 255 operations that are enabled by additional airport efficiency from the use of the proposed new procedure.

The implementation of a new procedure is considered a Federal action with potential to cause environmental impacts. Therefore, FAA must comply with the National Environmental Policy Act (NEPA) and other relevant laws. As a part of the NEPA process, the FAA has prepared a Draft Environmental Assessment that details the proposed new procedure and potential environmental impacts as a result of the new procedure to BOS.

Información Sobre Proyecto

La Administración Federal de Aviación (FAA) está proponiendo introducir un nuevo instrument approach procedure (IAP) a la Pista 4L en el Aeropuerto Internacional Boston Logan (BOS). Este procedimiento nuevo, a que se refiere como procedimiento RNAV (GPS) RWY 4L, proporcionará aseguramiento mejorado para los aviones acercando a la Pista 4L y también proporcionará que BOS tenga habilidad de operar de manera más eficaz bajo condiciones de tiempo inclemente.

La FAA ha incluido un video que da un repaso breve sobre el propuesto procedimiento nuevo a la Pista 4L en BOS. Este video presenta información sobre el diseño de BOS y el trayecto anticipado del procedimiento, incluyendo animaciones de puntos de ruta trazados y transiciones a la Pista 4L. El video trata de los 359 vuelos anuales que se anticipan usar el propuesto procedimiento nuevo.  Estos 359 vuelos anuales son compuestos de 104 operaciones que serían re-asignados desde las otras pistas de llegada y 255 operaciones que serían posibles como resultado de mejoramientos de eficiencia relacionados con el propuesto procedimiento nuevo.

La implementación de un procedimiento nuevo se considere como una acción federal con la posibilidad de causar impactos al ambiente. Así que la FAA tiene que cumplir con la National Environmental Policy Act (NEPA) y otras leyes relevantes. Como parte del proceso de NEPA, la FAA ha preparado un Draft Environmental Assessment que describe los detalles del propuesto procedimiento nuevo y los impactos ambientales potenciales que podrían resultar del procedimiento nuevo en BOS.


Provided below is a copy of the Draft Environmental Assessment prepared by FAA, separated by individual chapters and technical appendices.

NEPA & Environmental Review

This page provides an overview of NEPA and the review process used to evaluate potential environmental impacts in communities surrounding BOS. The page also provides a description of the Environmental Assessment process, including where FAA is in this process and the associated next steps.

Aircraft Noise Overview

A new arrival procedure has potential to introduce noise impacts in communities along the proposed new flight path to Runway 4L. FAA has provided an overview of aircraft noise on this page, including how it is measured and the metric FAA uses to assess whether noise impacts are considered “significant” under NEPA’s environmental review.

Summary of EA Findings

The environmental assessment process separates the potential environmental impacts into different types of environmental categories. The page gives a summary of the primary findings from this Draft Environmental Assessment separated by impact category in both English and Spanish.


This section includes various FAA and environmental resources to allow you to dig further into the applicable environmental regulations, other FAA environmental reviews, and more information about aviation environmental issues.