The JPX Dashboard tracks aircraft operations, estimated noise levels, and curfew compliance at East Hampton Airport (KJPX) in East Hampton, New York. It is built and maintained by Marc Frons, as an independent civic data project, to give residents, elected officials, and the public a clear, factual picture of airport activity and its impact on surrounding communities.

The dashboard does not advocate for a particular outcome. It presents data drawn from public and commercial sources, documents differences between published standards, voluntary commitments, and observed operations, and makes that record available for anyone to examine. Everything visible in the dashboard is explained on this page.

The dashboard includes dedicated analysis pages for the three aircraft categories of greatest community concern: Helicopters, Seaplanes, and Jets. Each page provides operator scorecards, curfew-period operation rates, route analysis, and seasonal trends specific to that category.

Three external sources feed the dashboard. Each covers a distinct part of the picture.

Operator Identification

The dashboard identifies aircraft operators through two sources. FlightAware provides operator names for commercial and charter flights — companies like NetJets, Blade, Flexjet, and VistaJet. For the remaining flights — primarily Part 91 private operations where FlightAware does not identify the operator — we cross-reference the aircraft's tail number (N-number) against the FAA Aircraft Registration Database, a public record maintained by the Federal Aviation Administration.

This dual approach resolves the registered owner for the vast majority of flights at KJPX. A small percentage of flights remain unresolved, typically due to temporary registrations, foreign-registered aircraft, or data entry discrepancies.

Data Freshness

Flight data updates multiple times per day via the FlightAware AeroAPI. The Data Through date in the dashboard header reflects the most recent data in the system. GPS ground track data is available for most flights, with the best coverage from mid-2025 forward. The dashboard defaults to the previous calendar month. Operator compliance grades are calculated based on the currently selected time period. For the most meaningful assessment, we recommend selecting longer time periods (90 days or more) — shorter periods may produce volatile grades due to smaller sample sizes.

The FAA Aircraft Registration Database is a public-domain dataset that links each N-number to its registered owner — whether that's an individual, an LLC, a corporation, or a trust. JPXWatch uses this data to identify the registered owner of aircraft where FlightAware does not provide an operator name.

What Is Shown

• Registered owner name — the entity (company, LLC, trust, or individual) listed as the owner in the FAA database
• Registrant type — Corporation, LLC, Individual, Partnership, Government, etc.
• Aircraft make and model — from the FAA aircraft reference data, when available

Privacy

The FAA registry includes the registered owner's mailing address. JPXWatch does not display individual owner addresses. For business entities (corporations, LLCs, trusts), the entity name alone provides sufficient identification. For individual owners, we display the name but suppress the address.

Data Source

Source: FAA Releasable Aircraft Database (registry.faa.gov). Public domain, no restrictions on use. Refreshed monthly.

JPXWatch uses the Town of East Hampton's published curfew as the primary standard for classifying nighttime operations. The Town publishes its curfew on its Flight Planning page and states it in a single line:

Curfew (All Aircraft)

10 p.m. to 7 a.m.

Source: Town of East Hampton — Flight Planning

The Town's published language is quoted verbatim. It contains no carve-outs for aircraft category, no weekend exception, and no separate tighter window for noisy aircraft. JPXWatch flags any operation with a wheels-up or wheels-down time at KJPX within the 10 PM – 7 AM Eastern window as a curfew period operation, regardless of aircraft type.

A published standard, not an enforceable rule

The Town publishes the curfew as a standard, but it is not enforceable as a matter of federal law. Under the Airport Noise and Capacity Act of 1990 (ANCA), a public-use airport proprietor cannot impose noise or access restrictions without following a specific procedural process culminating in FAA approval. East Hampton has not completed that process. Federal court rulings have consistently blocked the Town's attempts to impose binding noise restrictions, beginning with the Second Circuit's November 2016 decision in Friends of East Hampton Airport, Inc. v. Town of East Hampton (No. 15-2334), which enjoined the Town's earlier curfew ordinances on ANCA procedural grounds.

In practical terms this means operators choose whether to observe the curfew. There is no fine, no fee, no loss of airport access. JPXWatch records operations that occur within the published 10 PM – 7 AM window as curfew period operations because the Town has published that window as the standard — not because a legally-binding rule has been broken. The dashboard's purpose is to show the public record of what happens at the airport relative to the standard the Town has chosen to publish.

Methodology update — April 2026

Prior to April 2026, JPXWatch classified operations against a 9 PM – 7 AM window drawn from the East Hampton Community Alliance's voluntary Pilot Pledge, a separately-published commitment by some operators. That window is tighter than the Town's published 10 PM curfew by one hour. In April 2026 we updated the primary standard to match what the Town itself publishes on its Flight Planning page, and re-ran historical data under the new threshold. Curfew counts on the dashboard decreased as a result, because operations landing or taking off between 9:00 PM and 9:59 PM are no longer classified as curfew operations under the published Town standard. In the same update, we corrected a separate issue where some historical curfew flags had been computed from estimated rather than observed flight times; flags derived from forecasts have been cleared and will no longer be written going forward.

Two other standards exist in public discussion of nighttime operations at KJPX and are worth naming:

• Pilot Pledge (9 PM – 7 AM). A voluntary commitment published by the East Hampton Community Alliance, an operator-affiliated organization. Tighter by one hour than the Town's published curfew. Full text below. JPXWatch used this as its primary standard prior to April 2026.
• 11 PM – 7 AM, fixed-wing voluntary (Sound Aircraft Services). The fixed-base operator at KJPX publishes an article describing a separate voluntary effort with fixed-wing operators: “The East Hampton Airport has been working with fixed-winged aircraft owners, pilots, and their passengers to observe the voluntary curfew from 11:00 PM to 7:00 AM.” This standard is one hour later than the Town's published curfew and is limited in scope to fixed-wing aircraft — it does not mention helicopters. This standard is documented here for completeness.
  Source: Sound Aircraft Services — Voluntary Curfew at the East Hampton Airport

We chose the Town's 10 PM – 7 AM window as the primary standard because it is what the municipal government of East Hampton — the airport's legal proprietor — has chosen to publish, and because it applies to all aircraft uniformly without category carve-outs. The Pilot Pledge and the SAS-documented 11 PM fixed-wing standard represent alternative community norms and operator practice, and are documented here as context. The dashboard's primary curfew count and compliance grades are computed against the Town's published window.

The Pilot Pledge (alternative standard, documented for context)

The Pilot Pledge is the voluntary commitment JPXWatch previously used as its primary standard. It is published by the East Hampton Community Alliance, an operator-affiliated organization (not a Town of East Hampton government body), and includes a tighter 9 PM – 7 AM curfew window along with four other commitments. The full text is reproduced below for reference.

Terms used throughout the dashboard, in plain English.

Published Helicopter Routes

East Hampton Airport (KJPX) has three published helicopter arrival and departure routes, established for noise abatement:

• Echo Route (North Shore) — Available for both arrivals and departures. Connects to the North Shore Helicopter Route. This is the airport's designated preferred noise abatement route. Waypoints must be flown precisely per the published procedure.
• November Route (South Shore) — Arrivals only. Connects from the South Shore Helicopter Route via Shinnecock Inlet. Voluntary; intended to spread traffic and reduce congestion on Echo.
• Sierra Route (South Shore) — Departures only. Available only when traffic permits (no fixed-wing traffic south of the airport). Connects to the South Shore Helicopter Route.

Source: East Hampton Town Airport, "Helicopter Arrival and Departure Routes," Rev. 3, 03/04/2025.

How Flights Are Classified

We use two methods to determine which route each helicopter used, depending on available data:

Track-Based Classification (higher confidence)

Approximately 37% of helicopter operations have detailed ADS-B flight track data — a series of GPS position reports showing the aircraft's actual path, altitude, and speed throughout its flight. For these flights, we compare the actual track against the published waypoint coordinates for each route:

• Echo waypoints: E1, E2, E3, E4 (with altitude checkpoints at 2,500 ft for departures, 3,500 ft for arrivals)
• November waypoints: Shinnecock Inlet, PECONIC, N1, N2, N3 (with 3,500 ft altitude checkpoint at N1)
• Sierra waypoint: S1 (departures proceeding south toward the South Shore Route)

A flight is classified to a route if its track passes within 1 nautical mile of the route's waypoints in the correct sequence and direction. Flights with track data that do not match any published route are classified as "Non-Standard."

Origin/Destination Estimation (lower confidence)

The remaining ~63% of helicopter operations do not have detailed track data, but we do know their origin or destination airport and whether they were arriving at or departing from JPX. We estimate the likely route based on this information:

• Arrivals from north or west (Manhattan heliports, Teterboro, White Plains, Farmingdale, etc.) → Estimated Echo (the preferred North Shore Route)
• Arrivals from South Shore origins (Gabreski/Westhampton) → Estimated November
• All departures → Estimated Echo (we cannot verify Sierra's "traffic permitting" condition without tower communications, so we conservatively default to the preferred route)

Estimated flights are never classified as "Non-Standard" because we cannot determine actual route adherence without track data.

Altitude Adherence

For flights with GPS track data, we check altitude at each published checkpoint waypoint. A flight is considered "compliant" at a checkpoint if its altitude is within ±300 feet of the published altitude requirement. Altitude adherence data is only available for track-based classifications, not for estimated flights.

What This Data Shows — and What It Doesn't

The purpose of this analysis is to provide the community with objective, data-driven insight into helicopter route usage patterns at East Hampton Airport to support informed discussion about noise impacts.

Data Sources

• Flight data: FlightAware AeroAPI — aircraft identification, flight tracks, origin/destination, aircraft type
• Route definitions: East Hampton Town Airport, "Helicopter Arrival and Departure Routes," Rev. 3, 03/04/2025
• Aircraft noise levels: FAA/EASA Part 36 type-certification data
• Helicopter type information: FAA aircraft registry, manufacturer published specifications

Seaplane Classification

Seaplanes are identified using a three-layer detection method:

1. Known float plane types — Aircraft with ICAO type designators that are exclusively float planes (DHC-2 Beaver, DHC-3 Otter).
2. Known seaplane operators — Flights operated by companies known to operate float-equipped aircraft at KJPX, including Tailwind Air and Tropic Ocean Airways.
3. Route-based inference — Candidate aircraft types (Cessna 208 Caravan, Daher Kodiak 100) routing via NYC Skyports Seaplane Base, which is exclusively a water-landing facility.

This layered approach is necessary because the ICAO type code for a Cessna Caravan (C208) is the same whether the aircraft is on wheels or amphibious floats. The FAA Aircraft Registry, operator identity, and route origin together resolve the ambiguity.

Key Seaplane Operators at KJPX

• Tropic Ocean Airways (Blade contractor) — Cessna 208 Caravan
• Tailwind Air — Cessna 208 Caravan (amphibious)
• FlyTheWhale — Cessna 208B Grand Caravan (amphibious)
• Acadian Seaplanes (Blade contractor) — Cessna 208 Caravan

Helicopter Corridor Proximity Analysis

The Seaplane Activity page includes an analysis of whether seaplane flight tracks intersect the published helicopter corridors (Echo, November, Sierra). This addresses a concern raised by community members and Town officials: that seaplanes may be using routes designated for helicopters.

The Pilot Pledge commits that “all seaplane operators agree to standardize seaplane arrival and departure routes corresponding to the least noise-sensitive areas.” The corridor proximity analysis provides data to assess adherence to this commitment.

Methodology:

• Helicopter corridor boundaries are defined from coordinates published by the Town of East Hampton.
• Corridors are buffered at 1.0 nautical mile from centerline.
• Each seaplane flight track is checked for intersection with corridor polygons.
• Flights with >25% of track positions inside a helicopter corridor are flagged as having significant overlap.
• Some corridor intersection is expected on standard approaches to Runway 28, as the November corridor crosses the approach path. Brief intersection during approach does not necessarily indicate a seaplane was using the helicopter corridor as its route.

Data Sources

• Flight tracks: FlightAware AeroAPI
• Corridor definitions: East Hampton Town Airport, "Helicopter Arrival and Departure Routes," Rev. 3, 03/04/2025

Jet Classification

Jets are identified by ICAO aircraft type designator and engine classification. All turbojet and turbofan-powered fixed-wing aircraft are classified as jets. Turboprop aircraft are tracked separately.

Unlike seaplanes, jet classification is unambiguous from the aircraft type code — no layered detection is required.

Aircraft Size Classes

Jets at KJPX range from very light jets to ultra-long-range aircraft, with significant variation in noise impact:

• Very Light Jet (VLJ): Eclipse 500, Phenom 100 (~70–75 dB(A))
• Light: Citation CJ3, Phenom 300 (~75–80 dB(A))
• Midsize: Citation XLS, Learjet 60 (~78–83 dB(A))
• Super-Midsize: Citation Longitude, Challenger 350 (~80–85 dB(A))
• Large: Gulfstream G450/G550, Falcon 900 (~83–88 dB(A))
• Ultra-Long-Range: Gulfstream G650/G700, Global 7500 (~85–90 dB(A))

Each 10 dB(A) increase represents approximately a doubling of perceived loudness. A Gulfstream G650 on approach is roughly four times as loud to the ear as a Cessna 172.

Runway Corridor Analysis

Unlike helicopters and seaplanes, which have some flexibility in routing, jets are constrained to the runway centerline on approach and departure. IFR procedures, PAPI guidance, and ATC instructions keep them on a narrow, predictable path. This means jet noise is highly concentrated on a specific geographic band — and residents under that band bear a disproportionate burden.

The Jet Activity page analyzes flight tracks relative to the extended runway centerlines:

• Runway 28 approaches (the dominant arrival direction during prevailing westerly winds)
• Runway 10 departures
• Runway 16/34 operations (secondary crosswind runway)

Altitude compliance is also assessed: the Pilot Pledge asks jet pilots to maintain 1,500 ft until maneuvering for landing. The dashboard checks actual altitude profiles against this commitment.

Operator Categories

Jet operators at KJPX fall into distinct categories:

• Fractional operators (NetJets, Flexjet, WheelsUp, PlaneSense) — sell shares of aircraft, generating high-frequency repeat visits
• Charter operators — on-demand service
• Corporate/Private — individual or company-owned aircraft

This categorization helps distinguish high-volume commercial operations from occasional private flights.

Historical Context: Stage 3 Restrictions

The Town of East Hampton attempted to restrict Stage 3 jets (the oldest and loudest noise certification standard) in 2015–2017. Federal courts struck down these restrictions, ruling they violated grant assurances under the Airport Noise and Capacity Act. The Jet Activity page shows the current mix of Stage 3, Stage 4, and Stage 5 aircraft operating at KJPX.

Data Sources

• Flight data: FlightAware AeroAPI
• Aircraft type classification: ICAO Doc 8643
• Noise certification levels: EASA/FAA Part 36 type-certification data

Why Weather Matters for Airport Noise

Weather — especially wind direction — is the single biggest factor determining which runway is active and where aircraft fly. When the wind shifts, flight paths shift with it, and neighborhoods that were quiet one day can be under the flight path the next. Temperature, visibility, and atmospheric conditions also affect how far and how loudly sound travels on the ground.

The Weather Correlation Analysis page connects real weather observations to flight operations and noise data at East Hampton Airport, helping the community understand why certain days or seasons are louder than others.

What's on the Page

Current Conditions

Live weather data for the JPX area including temperature, wind speed and direction, sky condition, visibility, and flight category (VFR/MVFR/IFR). Updated automatically from NOAA aviation weather observations.

Wind Speed vs. Noise Level

Scatter plot showing the relationship between wind speed and average estimated noise level for each observation period. Higher winds can both change flight paths and affect how sound propagates to the ground.

Temperature vs. Operations

Scatter plot showing how temperature correlates with flight activity. At JPX, warm-weather weekends see significantly higher operations than cool weekdays — a pattern driven by seasonal Hamptons travel demand.

Operations by Weather Condition

Breakdown of total flight operations by sky condition (Clear, Partly Cloudy, Overcast, Rain, Fog, Wind Advisory). Includes the average noise level associated with each condition. Operations tend to decrease in poor weather, but the noise per operation may vary.

Wind Rose — Operations by Direction

Polar chart showing how many operations occurred under each wind direction, color-coded by estimated noise level. This reveals which wind patterns correlate with the highest noise exposure. At JPX, prevailing southwest winds during summer push departures over south shore communities on Runway 28.

Key Insights

Auto-generated plain-English findings based on the data for the selected period. These highlight significant patterns — seasonal trends, weather-driven operational changes, and noise correlations.

“Today at JPX” on the Main Dashboard

The main dashboard includes a “Today at JPX” section showing current conditions and a brief explanation of what they mean for flight activity:

• Current temperature, sky condition, and wind speed/direction
• Which runway is likely active based on wind direction (JPX runways are 10/28, roughly east-west)
• Today's operations count with context (above/below average for the period)

This section updates live and provides a quick answer to the question “what's happening at the airport right now?”

How Wind Direction Affects Runway Usage

East Hampton Airport has one primary runway: Runway 10/28, oriented roughly east-west.

• Winds from the west or southwest → Runway 28 active (aircraft land from the east, depart to the west). Departures typically overfly communities south and west of the airport.
• Winds from the east or northeast → Runway 10 active (aircraft land from the west, depart to the east). Departures overfly communities east of the airport.
• Light and variable winds (below ~5 knots) → Mixed runway usage. ATC may use either runway based on traffic flow, and flights may approach from either direction.

Understanding wind direction explains why noise patterns change day to day even when the total number of operations is similar.

Temperature Inversions

On some days, noise at ground level seems louder than usual even though operations haven't increased. This is often caused by a temperature inversion — a weather condition where a layer of warm air sits above cooler air near the surface. Normally, sound dissipates upward as it travels. During an inversion, sound waves are bent back toward the ground, effectively trapping and amplifying noise at the surface.

Temperature inversions are most common during calm, clear evenings and early mornings. The Weather Correlation Analysis page flags periods when inversion conditions are likely, based on temperature profile data from the NWS radiosonde station at Upton, NY (OKX).

Flight Categories: VFR, MVFR, IFR

The current conditions display includes a flight category badge. These categories are defined by the FAA based on visibility and cloud ceiling height:

• VFRVisual Flight Rules — Ceiling above 3,000 ft and visibility greater than 5 miles. Good flying conditions. The published helicopter routes at JPX (Echo, November, Sierra) are designed for VFR conditions.
• MVFRMarginal VFR — Ceiling 1,000–3,000 ft or visibility 3–5 miles. Pilots can still fly visually but with reduced margins. Some operators may delay or cancel flights.
• IFRInstrument Flight Rules — Ceiling below 1,000 ft or visibility below 3 miles. Pilots must rely on instruments. Helicopter operations are typically reduced or suspended. Published VFR helicopter routes may not be available.
• LIFRLow IFR — Ceiling below 500 ft or visibility below 1 mile. Very poor conditions. Most helicopter operations are suspended.

Lower flight categories generally mean fewer operations but do not eliminate them — instrument-rated pilots and aircraft can still operate in reduced conditions.

Data Sources

• Weather observations: NOAA Aviation Weather Center (aviationweather.gov). Real METAR and TAF reports for the JPX area. No API key required.
• Temperature inversion analysis: NWS radiosonde station OKX (Upton, NY) upper-air soundings.
• Flight data: FlightAware AeroAPI — correlated with weather observations by timestamp.
• Noise estimates: FAA/EASA Part 36 type-certification profiles, applied to each operation based on aircraft type, altitude, and distance.

What It Shows

The Carbon Emissions module estimates the CO₂ produced by flight operations at East Hampton Airport based on aircraft type, fuel burn rates, and flight duration. It provides:

• Total CO₂ for the selected period across all operations
• Per-operation average in kilograms
• Car-year equivalent — total emissions translated into the equivalent number of average passenger cars driven for one year, using EPA's figure of 4.6 metric tonnes CO₂ per car per year
• Top emitters by aircraft type — which aircraft types contribute the most total CO₂, ranked by aggregate emissions rather than individual flight impact
• Category breakdown — share of total emissions from jets, fixed wing, helicopters, and unclassified aircraft

How Emissions Are Calculated

Each operation's CO₂ estimate follows a three-step calculation:

1. Aircraft type → fuel burn rate

Every aircraft type has a known approximate fuel consumption rate based on its engine model and configuration. We use published fuel burn data from the ICAO Aircraft Engine Emissions Databank and manufacturer specifications to assign a fuel burn rate (in kg per hour) to each aircraft type observed at JPX.

2. Fuel burn × flight duration → total fuel consumed

Flight duration is sourced from FlightAware data for each operation. For operations without precise duration data, we use average flight times for typical JPX routes (e.g., approximately 35–45 minutes for NYC-Hamptons helicopter shuttles).

3. Fuel consumed × emission factor → CO₂

We apply standard emission conversion factors:

• Jet A-1 fuel (used by turbine aircraft — jets and turboprops): 3.16 kg CO₂ per kg of fuel burned
• Avgas (used by piston aircraft): 3.10 kg CO₂ per kg of fuel burned

These conversion factors are established by the International Civil Aviation Organization (ICAO) and are consistent with those used by the FAA, EASA, and EnviroSuite's carbon emissions module.

What These Estimates Include — and What They Don't

These estimates represent the direct flight-phase carbon footprint of airport operations. Actual total climate impact is higher when upstream and non-CO₂ effects are included.

Accuracy and Limitations

Carbon emissions estimates are approximate. Actual fuel consumption varies based on specific engine variant within a type family, payload, weather conditions (headwinds increase fuel burn), and pilot technique and ATC routing.

For community-level environmental intelligence, these estimates provide a reliable indicator of the relative scale and trend of aviation carbon emissions at JPX. They are suitable for understanding patterns and comparing periods, but should not be used as precise accounting for regulatory or offset purposes.

Data Sources

• Aircraft type and flight duration: FlightAware AeroAPI
• Fuel burn rates: ICAO Aircraft Engine Emissions Databank; manufacturer published specifications
• Emission conversion factors: ICAO standard factors (3.16 kg CO₂/kg Jet A-1; 3.10 kg CO₂/kg avgas)
• Car-year equivalence: U.S. EPA figure of 4.6 metric tonnes CO₂ per average passenger car per year

Data Source

Flight data is sourced from FlightAware's AeroAPI, which aggregates FAA radar, ADS-B, and airline data. Flight tracks represent actual GPS ground track data, not modeled or synthetic paths. Data is updated daily.

Aircraft Noise Levels

Estimated noise for each flight is derived from EASA/FAA Part 36 type-certification data — the internationally standardized noise measurement that every certified aircraft must undergo. Each aircraft type has published reference noise levels measured during certification flight tests at three standardized points defined by 14 CFR Part 36: a lateral (sideline) point 450 meters from the runway centerline, a flyover point 6,500 meters from the start of takeoff roll, and an approach point 2,000 meters from the runway threshold. JPXWatch's propagation model uses a reference distance of 1,000 feet (304.8 meters) for its attenuation calculations, applying geometric spreading and atmospheric absorption from that baseline. JPXWatch maintains an EASA-derived noise profile mapping for 47 ICAO aircraft type codes, covering the helicopter, jet, and fixed-wing types most commonly observed at KJPX. Aircraft types not present in the mapping receive a category-average estimate based on whether they are classified as helicopter, jet, or fixed-wing.

Part 36 certification data is the foundational noise source used throughout aviation noise regulation. The FAA's Aviation Environmental Design Tool (AEDT) — the agency's required model for all domestic regulatory noise analyses under FAA Order 1050.1F — computes noise contours using Noise-Power-Distance (NPD) curves derived from certification flight test data (AEDT Technical Manual §11.3.4; FAA ASCENT Center of Excellence). ICAO Doc 9911, the international standard for computing noise contours around airports, is explicitly “designed to make full use of” the Aircraft Noise and Performance (ANP) database assembled by manufacturers in collaboration with noise certification authorities. AEDT is Doc 9911-compliant. JPXWatch uses the same published certification values that feed these regulatory tools, applying a simplified propagation model rather than full NPD segmentation.

Altitude: MSL to AGL Correction

FlightAware reports aircraft altitude as MSL (Mean Sea Level) — the standard used by aircraft altimeters and air traffic control. However, noise impact at the ground depends on the aircraft's height above the listener, known as AGL (Above Ground Level).

JPXWatch converts MSL altitude to estimated AGL by subtracting a constant ground elevation appropriate to the KJPX area. The noise footprint calculator uses the airport field elevation of 55 feet MSL; the live noise trail visualization uses 30 feet, an average for the flat coastal plain between Wainscott and Montauk. A future version will integrate per-location terrain data from the USGS National Elevation Dataset to replace these fixed values.

Terrain across Long Island's South Fork is relatively flat, with elevations typically ranging from 20 to 80 feet MSL, with some higher points along the glacial moraine running through Wainscott and East Hampton. The constant-elevation approach is a reasonable approximation for this terrain, though it does not capture per-property differences. A helicopter reported at 500 feet MSL over terrain at 55 feet elevation is calculated as 445 feet above the ground.

Distance Attenuation

Noise decreases with distance from the source. JPXWatch estimates received noise at ground level using slant distance — the true straight-line distance from the listener to the aircraft, calculated as:

Slant distance = √(ground distance² + altitude²)

Where ground distance is the horizontal distance from the listener's location to the nearest point on the aircraft's GPS track, and altitude is the AGL-corrected height at that point.

Sound attenuation is modeled using geometric spreading (inverse-square law: noise decreases by 6 dB(A) per doubling of distance) plus atmospheric absorption (approximately 0.5 dB(A) per 1,000 feet of additional distance). The estimated noise at the receiver is:

Received noise (dB(A)) = Reference noise − 20 × log₁₀(slant distance / reference distance) − (0.5 × slant distance / 1,000)

Severity Levels

85 dB(A) is a project-defined accountability threshold used by JPXWatch. It corresponds to the upper edge of the typical operations band at KJPX (most operations fall in the 75–84 dB(A) range) and flags operations meaningfully above the prevailing acoustic baseline. It is not an FAA regulatory standard, and JPXWatch does not claim parity with formal noise monitoring systems such as Casper Noise Lab or Envirosuite, which use calibrated Type 1 microphones at known ground locations. JPXWatch exists to provide community-level transparency in the absence of installed monitoring infrastructure at KJPX, and supports the installation of professional noise monitoring as the next step toward accurate community noise data.

JPXWatch's approach — correlating aircraft type with noise characteristics using certification data — is consistent with the methodology used by established airport noise transparency platforms worldwide. WebTrak (Envirosuite/Brüel & Kjær), deployed at JFK, LaGuardia, Newark, Reagan National, LAX, and across Australia's Airservices network, integrates flight tracking with aircraft-type-based noise data. Casper Noise serves Amsterdam Schiphol, London Gatwick, and Tampa International. Noise-Map.com estimates aircraft noise globally using ADS-B flight data and aircraft-type-based propagation modeling. None of these systems claim to replace calibrated ground monitoring; all use aircraft type identification — the same certification-linked variable — as a core input for noise characterization.

Relationship to Peer-Reviewed Methodology

Feng, Zhou, Zeng & Ding (2023), “Review on Metrics and Prediction Methods of Civil Aviation Noise” (Int. J. Aeronaut. Space Sci. 24:1199–1213, full text, doi:10.1007/s42405-023-00609-0), classify aviation noise prediction models into three families: best-practice, scientific, and machine-learning. JPXWatch is a simplified best-practice implementation: it treats each aircraft as a noise point source — the defining feature of the family that includes FAA AEDT, the legacy INM, and ECAC Doc 29 — but omits their Noise-Power-Distance curves, lateral attenuation adjustments, and flight-path segmentation.

We pair DNL with a Number-Above-threshold count, surfaced as the High-Noise Events metric. Supplementing energy-averaged metrics with event counts is the approach recommended under EU Directive 2002/49/EC for noise environments dominated by short-duration events — the profile of a seasonal general-aviation airport, where annualized averages understate community impact.

The certification-data approach that JPXWatch simplifies from has been validated at scale in peer-reviewed research. Rindfleisch et al. (2024), in the largest AEDT validation study to date, compared model predictions against ground-level measurements for 200,000 arrival trajectories at San Francisco International Airport over 12 months, finding mean differences of −2.04 dB(A) for sound exposure level and −3.09 dB(A) for maximum sound level (Journal of the Acoustical Society of America 155(3):1928). A multi-model comparison by Meister et al. (2021) tested three noise programs (sonAIR, FLULA2, and AEDT) against several thousand single-flight measurements at Zurich and Geneva airports, finding mean differences smaller than ±0.5 dB(A) in close proximity to airports (Aerospace 8(12):388). At Amsterdam Schiphol, Simons et al. (2022) confirmed that aircraft categorized by noise certification class tracked measured noise trends over six years, with a decreasing trend of 0.6 dB(A)/year reflecting the fleet's transition to quieter-certified types — directly validating that certification categories reflect real-world noise behavior.

Certification noise levels provide reliable relative rankings of aircraft types by noise output. JPXWatch's primary analytical value is comparative: identifying which aircraft types, operators, and time periods produce more or less noise impact at the community level, not certifying the precise decibel level at any listener's property.

The remaining gap to a full best-practice implementation is ground-truth calibration against Type 1 (IEC 61672-1 Class 1) reference microphones, which JPXWatch does not currently operate. Modeled levels should be read as directionally accurate estimates, not certified measurements.

Within-type variation

The event-level noise values on the scorecards are derived from Part 36 type-certification data — a standardized reference measurement taken under specified test conditions for a representative aircraft of each type.

Actual noise produced by a specific aircraft at KJPX may differ from its type-certification reference. Aircraft within the same ICAO type code can span decades of production with different engines, propellers, and airframes. Some older aircraft predate Part 36 certification entirely. Many types are delivered with multiple engine or propeller options that produce different noise profiles, and aftermarket modifications (STCs for engines, propellers, or mufflers) can further change an aircraft's noise signature. Operating technique, aircraft weight, and meteorological conditions also affect real-world noise.

Event level values should therefore be read as a comparative reference — useful for distinguishing a typical helicopter from a typical jet from a typical piston single — not as a prediction of what any specific aircraft produced on any specific flight. There are currently no official ground-based noise monitors at KJPX; all noise values are modeled.

The Noise Impact Score (0–100) is a composite metric that combines three factors to quantify the overall noise burden on the community. Each subscore is computed independently from per-day operation counts and then combined as a weighted average.

Fleet Mix Score (40% weight)

Measures the proportion of high-noise aircraft in the operations mix. Helicopters always count as high-noise. Jets count as high-noise only when their per-flight noise estimate (from Part 36 reference data adjusted for AGL altitude and slant distance) is at or above 85 dB(A).

min(100, (helicopters + loud_jets) / total_operations × 500)

The 500 multiplier is calibrated so that 20% high-noise operations yields a Fleet Mix subscore of 100. At 10% high-noise, the subscore is 50; at 5%, it is 25.

Concentration Score (30% weight)

Measures operations density. Higher daily operation counts produce higher subscores.

min(100, average_operations_per_day × 2)

The 2 multiplier is calibrated so that 50 operations per day yields a Concentration subscore of 100. At 25 operations per day, the subscore is 50.

Time-of-Day Score (30% weight)

Measures the share of operations occurring during the Town of East Hampton's published 10 PM – 7 AM curfew period. Non-curfew flights (including in-flight operations whose actual landing or takeoff time has not yet been observed) are excluded from this count under strict equality on the curfew flag.

min(100, curfew_operations / total_operations × 1000)

The 1000 multiplier is calibrated so that 10% curfew operations yields a Time-of-Day subscore of 100. At 5% curfew, the subscore is 50; at 1%, it is 10.

Composite Noise Impact Score

The three subscores are combined as a weighted average:

round(fleet_mix × 0.40 + concentration × 0.30 + time_of_day × 0.30)

The result is a single 0–100 number reflecting the overall noise burden from operations during the period.

Severity Tiers

• 0–39 — LOW. Minimal aircraft-noise burden. Quiet fixed-wing traffic predominates.
• 40–64 — MODERATE. Noticeable aircraft-noise burden. Elevated helicopter, jet, or curfew-period activity.
• 65–84 — HIGH. Significant aircraft-noise burden. Heavy concentration of louder aircraft and/or curfew operations.
• 85–100 — SEVERE. Upper portion of observed scores. Reflects sustained heavy traffic of louder aircraft, often combined with curfew or shoulder-hour activity.

The tier boundaries are project-defined and may be adjusted as the underlying score distribution changes. Tier assignment is computed from the score; it is not an editorial judgment about the operating period itself.

What Is DNL?

Day-Night Average Sound Level (DNL) is the FAA's primary metric for assessing aircraft noise impact around airports. It represents a 24-hour cumulative energy average of all aircraft noise events, with a 10 dB penalty applied to flights between 10 PM and 7 AM ET to account for the greater disruption of nighttime noise.

The FAA uses DNL in Part 150 noise compatibility studies to determine which areas around an airport experience "significant" noise exposure. The threshold is 65 dB DNL — any residence at or above this level is, by the FAA's own definition, incompatible with residential land use and may qualify for sound insulation programs under 14 CFR Part 150.

How JPXWatch Computes DNL

JPXWatch estimates DNL for each address using flight track data from FlightAware and noise reference levels from EASA/FAA Part 36 aircraft type-certification data. For each flight that passes within the user's selected radius:

1. The aircraft's type-certification noise level is looked up from Part 36 reference data.
2. The slant distance (straight-line distance from home to aircraft at closest approach) is computed from GPS track data and AGL-corrected altitude, as described in the Noise Estimation Methodology above.
3. The noise level is adjusted for distance using the inverse-square law.
4. A Sound Exposure Level (SEL) is estimated using a standard 15-second flyover duration.
5. Flights between 10 PM and 7 AM receive the standard 10 dB nighttime penalty.
6. All events are energy-averaged over the full season (Memorial Day through Labor Day) to produce the DNL value.

What This Model Does Not Capture

Why DNL May Understate Impact at Seasonal Airports

DNL was designed for high-volume commercial airports like JFK, which handle over 1,200 flights per day. At those volumes, noise events are nearly continuous throughout the day, and the 24-hour energy average produces numbers that meaningfully reflect the acoustic environment.

East Hampton Airport (KJPX) operates on a fundamentally different pattern. During summer high season, a typical day sees 10–40 operations — orders of magnitude fewer than a commercial hub. Each individual event may be loud (80–95+ dB(A) at close range for helicopters and jets at low altitude), but the long quiet intervals between events pull the 24-hour average down substantially.

The result: even the most impacted addresses near KJPX will produce estimated DNL values well below the FAA's 65 dB threshold. This does not mean the noise is insignificant. It means DNL is poorly calibrated for seasonal, low-frequency airports where the problem is intense individual events, not continuous background exposure.

This is a recognized limitation in the acoustics community. The FAA itself acknowledges supplementary metrics — including Sound Exposure Level (SEL), Maximum Sound Level (Lmax), and Number Above threshold (NA) — as complements to DNL in its own guidance documents. JPXWatch addresses this gap with the High-Noise Events metric described below.

The Nighttime Penalty

DNL applies a 10 dB penalty to flights between 10 PM and 7 AM — the FAA's standard nighttime window for acoustic exposure modeling. This happens to coincide with the Town of East Hampton's published curfew of 10 PM – 7 AM, but the two standards serve different purposes and are computed independently: DNL is an acoustic weighting used for noise exposure modeling under Part 150, while the curfew is an operational standard for when aircraft should not be flying.

What Are High-Noise Events?

A High-Noise Event is any individual flight where the estimated noise level at your address exceeded 65 dB — the same threshold the FAA uses in Part 150 to define "significant" noise exposure.

Where DNL tells you the season-long average, High-Noise Events tells you how many times aircraft noise was individually disruptive at your specific address. This is the metric that maps to lived experience: nobody experiences an average. You experience a helicopter at 500 feet, a jet on final approach, or a curfew-hour departure.

Why This Metric Matters

At a seasonal airport like KJPX, DNL systematically understates impact because it averages a small number of loud events across long quiet periods. High-Noise Events captures what DNL averages away: the actual count of disruptive moments in your day, your week, and your summer.

A resident who experienced 312 flights above 65 dB during summer 2025 has a concrete, defensible number to bring to a Town Board meeting — one that doesn't require explaining the mathematics of energy-averaged sound levels.

How It's Computed

The count is derived from the same flight data already displayed in the My Home Nearby Flights table. Each flight has an estimated noise level at the user's address (based on aircraft type, slant distance, and Part 36 reference data). The High-Noise Events count is simply the number of those flights where the estimate equals or exceeds 65 dB.

No additional data computation is required beyond what My Home already performs.

Limitations

What Is NoiseRank?

NoiseRank shows where your address falls on the spectrum of aircraft noise exposure relative to the broader East End community during East Hampton Airport's summer season (Memorial Day through Labor Day).

Your NoiseRank percentile compares your address's estimated DNL against a reference grid of evenly spaced points covering the KJPX impact zone — from Hampton Bays to Montauk, and from the South Fork across to the North Fork. A ranking of "Top 5%" means your address experiences more estimated aircraft noise than 95% of locations in the impact zone.

The Reference Grid

Rather than comparing only among self-selected users (which would introduce selection bias — people in noisy areas are more likely to check), NoiseRank compares against a pre-computed grid of points spaced 100 meters apart across the entire impact zone. The grid:

• Covers the geographic area defined by the convex hull of all observed flight tracks, plus a buffer
• Excludes points over open water
• Includes approximately 280,000 grid points (the exact count is displayed on the NoiseRank card)
• Is recomputed at the end of each summer season, and updated weekly during the live season

Each grid point has its own estimated DNL, computed using the same methodology described in the DNL section above. Your address's DNL is compared against this distribution to produce your percentile rank.

The Five-Band Scale

Why Low DNL Can Coexist with High NoiseRank

It is possible — and at KJPX, common — for an address to show a DNL well below 65 dB while also ranking in the top percentiles for NoiseRank. This is not a contradiction. It reflects two facts:

1. DNL is an absolute metric. As explained above, DNL at a seasonal airport will be low in absolute terms because the 24-hour averaging dilutes a small number of loud events across long quiet periods.
2. NoiseRank is a relative metric. It compares your address against all other locations in the impact zone. The vast majority of the East End — interior farmland, areas distant from flight paths, the North Fork — experience near-zero aircraft noise. Even modest flight activity puts an address near the airport in the upper percentiles, because most of the grid gets even less.

The Noise Exposure Heatmap on the Noise Map page makes this visually clear: the East End is overwhelmingly green, with concentrated yellow, orange, and red zones near the airport and under flight paths. An address in the red zone will have a high NoiseRank but may still fall below the FAA's 65 dB DNL threshold.

Both metrics are correct and useful. DNL anchors the data to the FAA's regulatory framework. NoiseRank shows where you stand relative to your community. Together with High-Noise Events, they provide a complete picture: how loud (DNL), how often (High-Noise Events), and how impacted compared to everyone else (NoiseRank).

Data Source

Flight tracks: FlightAware AeroAPI. Noise reference levels: EASA/FAA Part 36 type-certification data. Grid computation runs against locally stored data in the JPXWatch database — it does not make live API calls to FlightAware.

What Is the Noise Exposure Heatmap?

The Noise Exposure layer on the Noise Map page shows estimated cumulative aircraft noise across the KJPX impact zone, visualized as a color overlay on the map. It uses the same reference grid and DNL computation that powers NoiseRank, rendered geographically.

This is different from the Flight Density heatmap, which shows where aircraft fly. The Noise Exposure heatmap shows where noise accumulates on the ground — how sound radiates outward from flight paths and compounds over a season.

Color Scale

The color gradient is anchored to the FAA's DNL thresholds:

The 65 dB boundary between orange and red corresponds to the FAA's own definition of noise levels incompatible with residential land use.

How to Read the Map

• Green areas experience minimal aircraft noise impact during the summer season. This includes most of the East End's interior, the North Fork, and areas distant from KJPX flight paths.
• Yellow and orange areas experience moderate to significant noise exposure — these are communities under or near regular flight paths that may not consider themselves "airport-adjacent."
• Red areas (if present) exceed the FAA's 65 dB DNL threshold. At KJPX's current traffic volumes, this zone is concentrated immediately around the airport.
• The boundary line (dashed) shows the extent of the computed grid. Areas outside this boundary were not analyzed, not because they have zero noise, but because observed flight tracks do not extend there.

Overlay Opacity

The heatmap is displayed as a semi-transparent overlay on the base map. An opacity slider (default: 65%) allows you to adjust the balance between heatmap visibility and base map readability. Street names and place labels are rendered above the overlay to remain legible at all opacity levels.

Time Period

The heatmap currently shows data from the most recent completed summer season (Memorial Day through Labor Day). During the live summer season, it will update weekly to show season-to-date cumulative noise exposure. A "Summer 2025 (Historical)" or "Summer 2026 — Updated weekly" label is always displayed on the map.

Flight Track Color Coding

The Routes view on the Community Noise Map color-codes flight tracks by aircraft category rather than by estimated noise level. This provides immediate visual differentiation of traffic patterns:

This approach replaces the previous noise-level color coding, which produced visually undifferentiated maps because the majority of operations at KJPX fall within the same estimated noise band (75–84 dB(A)). Aircraft-type coloring makes the map immediately informative: helicopter corridors, seaplane routes, and jet approach paths are visually distinct without requiring any interaction.

A compact legend on the map doubles as a toggle control — click any category to show or hide its tracks. This works in conjunction with the aircraft category cards above the map.

Limitations

At a glance

Each operator's scorecard shows a letter grade (A–F) and six supporting fields. All fields are derived from FlightAware flight records and JPXWatch's modeled event-level noise estimates. Field definitions:

• Grade. A letter from A to F summarizing the operator's observable behavior at KJPX. Derived from an underlying numerical score, which is described in detail below but not shown on the card face.
• Flights. The total number of flights by this operator in the reporting window.
• Curfew. The count of flights recorded during the voluntary 10 PM – 7 AM curfew period that do not have an accepted exception.
• Curfew %. The percentage of the operator's flights that are within the curfew period. Displayed only when the operator has at least 5 flights; otherwise, a dash is shown to avoid misleading percentages from small samples.
• Shoulder-hour operations. The count of flights operated during the hour before curfew (9–10 PM) and the hour after curfew (7–8 AM).
• High-noise. The number of flights whose modeled event-level noise meets or exceeds JPXWatch's high-noise threshold of 85 dB(A). This is a project-defined single-event screening level, distinct from the FAA's 65 dB DNL cumulative exposure threshold.
• Event level. The typical modeled A-weighted noise level for an overflight from this operator, based on FAA/EASA Part 36 aircraft certification data and distance-based propagation assumptions. A modeled comparative value, not a ground-monitor reading.

Full methodology follows.

What the grades mean

Each operator is assigned a letter grade from A to F that summarizes observable operating behavior at KJPX within the time window covered by the dashboard's data. The grade is a comparative rating across the operator cohort — it ranks an operator relative to others flying in and out of KJPX, based on public FlightAware data and JPXWatch's modeled event-level noise estimates. It is not a regulatory determination, an FAA rating, or a judgment against any external compliance standard. JPXWatch grades do not purport to determine illegality, unsafe operation, or misconduct at any grade level.

Only the letter grade is shown on the scorecard. A numerical score is computed under the hood to determine which letter band an operator falls into. The numerical score is documented in full in the sections below, for methodology transparency.

Everything on the scorecard is grounded in observable events: a flight recorded by FlightAware, a departure or arrival during voluntary curfew hours, or a modeled noise estimate exceeding JPXWatch's high-noise threshold.

How the grade is computed

The grade is calculated using a deductible-balance model: every operator starts with a score of 100, and points are deducted for each observable deductible event (e.g., curfew period operation, high-noise event, shoulder-hour operation), subject to a limit on how much any single category can reduce the score. The final numerical score determines the letter grade.

The formula uses four inputs, applied from 100:

• Curfew period operations. Each flight operated during the voluntary curfew window (10 PM – 7 AM ET) incurs a 15-point deduction, capped at 60 points. Flights during the curfew period with accepted exceptions are not counted.
• High-noise events. Each flight whose modeled event-level noise met or exceeded JPXWatch's high-noise threshold of 85 dB(A) deducts 10 points, capped at a total deduction of 40 points.
• Shoulder-hour operations. Each flight operated during the hour immediately before the curfew begins (9–10 PM) or the hour immediately after it ends (7–8 AM) incurs a 2-point deduction, capped at 20 points.
• Average event-level noise. If an operator's mean modeled event-level noise across all flights exceeds 80 dB(A), 10 points are deducted. If the mean is between 75 and 80 dB(A), 5 points are deducted. Below 75 dB(A), no deduction applies. These tiers are mutually exclusive — not stacked.

Scores below zero are floored at zero; the theoretical minimum is 0, the maximum is 100.

Grade bands

The numerical score maps to letter grades on these bands:

• A: 90 or higher
• B: 80 to 89
• C: 70 to 79
• D: 60 to 69
• F: below 60

Grade boundaries are inclusive at the lower end — a score of exactly 80 is a B; a score of exactly 90 is an A.

As noted above, only the letter grade is displayed on the scorecard. The numerical score is used internally to assign the band.

What goes into the underlying fields

Curfew period operations. Each flight record carries an is_curfew_period flag derived from its timestamp. A flight counts as a curfew period operation if the flag is true and no accepted correction exempts it. Flights with pending or null exception status do not count.

High-noise events. For each flight, the dashboard computes a modeled event-level noise value from FAA/EASA Part 36 aircraft certification data and distance-based propagation assumptions. Flights with a modeled value at or above 85 dB(A) are counted as high-noise events. This 85 dB(A) threshold is a project-defined single-event screening level; it is distinct from the FAA's 65 dB DNL threshold, which applies to cumulative community noise exposure rather than individual flyovers.

Shoulder-hour operations. This count captures flights operated during the two single-hour buckets immediately adjacent to the curfew window: 9–10 PM (before curfew begins) and 7–8 AM (after curfew ends). It does not include the broader evening or early morning.

Average event-level noise. The mean of the modeled event-level noise values across all of the operator's flights in the reporting window.

Why this model

The formula assigns the heaviest penalty to curfew-period operations because they are the clearest, most binary signal in the data — an aircraft was either operating during the voluntary curfew or it was not. High-noise events are weighted next because they indicate that an individual flyover was loud enough to be disruptive. Shoulder-hour operations carry a lighter penalty because their impact is softer but still worth surfacing. Average noise level contributes last, because it reflects the operator's fleet composition and flight profile in a less event-specific way.

The caps on each category mean that no single dimension dominates the grade. An operator with many curfew-period operations will see their curfew penalty saturate at 60 points; additional curfew-period operations beyond that do not further reduce the grade. The same principle applies to the other categories. This makes the grade responsive to each dimension without letting any one metric overwhelm the others.

What the grade is not

Because these distinctions matter to how the grade should be read, they are stated here explicitly:

• The grade is not an FAA-issued determination or any form of regulatory classification. The FAA does not issue operator noise grades at KJPX or anywhere else.
• The grade is not a safety rating. It measures noise-related operating behavior, not operational safety.
• The grade is not a judgment about an operator's intent, professionalism, or character. It is a summary of observable events in the FlightAware data.
• The grade does not directly account for flight volume. An operator with five flights and an operator with five hundred flights can earn the same grade if their observable behavior — curfew period operations, high-noise events, shoulder-hour operations, average event-level noise — is comparable in aggregate.
• The grade is not a measure of cumulative community noise exposure, such as DNL. Metrics for community exposure — modeled DNL estimates and relative percentile rank — are presented separately on the DNL map and NoiseRank views.

Flight count and curfew rate

Flight count and curfew rate are shown on the scorecard as context, but they enter the grade formula only indirectly:

• Flight count does not feed the grade calculation. It is displayed so readers can see how many flights are being summarized.
• Curfew rate (the percentage of an operator's flights that are curfew period operations) is displayed only when the operator has at least 5 flights in the reporting window. Below that threshold, the percentage column shows a dash instead of a rate, because percentages computed from very small samples can be misleading.

Time period

The grade is computed over the time period selected by the user. Every field on the scorecard — flight count, curfew period operations, high-noise events, average event-level noise, and the grade itself — reflects only flights within the selected window. Selecting a different period recomputes all of them. An operator's grade is therefore not a fixed rating but a summary of their observed behavior during the chosen window, and grades will shift as the window changes.

A grade is only meaningful when paired with the window over which it was computed. A screenshot of a scorecard without its date range attached loses important context.

The dashboard defaults to a 30-day window. Shorter windows and periods with lower overall flight volume will produce more variable grades, because each event contributes proportionally more to each field. Longer windows and high-season periods produce more stable grades because there is more data in each category, and individual events carry less weight.

The dashboard does not retain or publish grades from previous sessions. Each grade shown is a live computation based on the current data, filtered by the selected period.

Data sources

All inputs to the grade come from two sources:

• FlightAware AeroAPI (Standard tier) provides flight records, timestamps, operator identification, aircraft types, and track data.
• FAA and EASA Part 36 aircraft type-certification data provide reference noise values per aircraft type, which are combined with flight geometry to produce modeled event-level noise estimates.

No physical noise monitors currently measure sound at KJPX; all noise values are modeled rather than measured. This limitation is inherent to the current dashboard and is acknowledged throughout the site.

Submitting a correction

If an operator believes the dashboard has misattributed a flight, misidentified an aircraft type, or made any factual error affecting their scorecard, they can submit a correction through the “Submit a correction about this operator” link on their scorecard. Corrections are reviewed and resolved publicly through the site's corrections log.

Intellectual honesty requires stating what this dashboard cannot do alongside what it can.

JPXWatch maintains a public record of material corrections to data and methodology changes that affect reported operations. This ensures users can track how reported figures and analytical approaches have evolved over time.

Material revisions to data and methodology — including the April 2026 Noise Impact Score correction, SEVERE tier adjustment, unified noise source-level data, approach-phase offset correction, ADS-B proximity verification of operations, and inbound-diversion exclusion — are maintained on a dedicated page: Methodology & Data Revisions. The April 11, 2026 curfew methodology realignment is documented in the Curfew Methodology section above.

JPXWatch is designed to provide accurate, sourced information about airport operations. The following guidance is for anyone who may cite this data in formal settings — town board meetings, press inquiries, regulatory submissions.

Questions about methodology or data should be submitted using the feedback form in the dashboard.