TagPerformance Based Navigation(9)

A document explaining changes to aircraft arrival patterns at SeaTac airport around 2015, including the introduction of Performance Based Navigation (PBN) technology and lowered flight altitudes. The changes concentrated flight paths over Vashon Island in a narrow corridor, causing increased noise pollution for residents who chose to live there for its peaceful environment.

This document is an invoice and monthly status report from Vianair Inc. submitted to the City of Alexandria for consulting services performed in December 2024, totaling $6,125.00. The work included noise analysis, procedure design, steering committee participation, and software services related to an Alexandria flight procedure project. The invoice was recommended for approval by representatives from Prince George's County and Fairfax County, and approved by a City of Alexandria senior environmental specialist.

Vianair Inc. submitted Invoice #1195 for $6,125.00 to the City of Alexandria for consulting services performed in December 2024, covering noise analysis, procedure design, and software services related to an airport flight procedure project. The accompanying monthly status report details 20.5 total hours of work by consultants Jim and Mark, along with Vianair software analysis, spanning tasks such as steering committee meetings, noise analysis, and final design review. The invoice was reviewed and approved by representatives from the City of Alexandria, Prince George's County, and Fairfax County in January 2025.

This document is an invoice from ABCx2, LLC to Arlington County, Virginia, for $19,637.50 in consulting services rendered during July and August 2021 as part of the Arlington Phase II project. The work included community working group (CWG) meetings and presentations, FAA-related briefings, noise abatement procedure drafting, and flight track data analysis performed by a team of consultants billed at $250–$350 per hour. The invoice reflects cumulative project spending of $76,637.50 against a total project budget of $150,000, leaving a remaining balance of $73,362.50.

This presentation by aviation consultant Jim Allerdice explores 'dispersion,' a strategy for reducing repetitive aircraft noise over residential neighborhoods by intentionally varying the lateral flight paths of aircraft. It distinguishes between natural dispersion, which occurs randomly with manually flown routes and air traffic control vectors, and systematic dispersion, which uses satellite-based navigation (RNAV) to spread flights across multiple precise, predictable tracks in a controlled way. Examples of systematic dispersion techniques discussed include radar vectors to RNAV, open Standard Instrument Departures (SIDs), and Equivalent Lateral Spacing Operations (ELSO).