Meeting Notes : Navigation Committee
Committee notes reflect the views and opinions of the committee members and not necessarily those of the Noise Compatibility Study Group, Coordinating Council, Regional Airport Authority of Louisville and Jefferson County, or the Consultant Team.
Attendees: Dannie Bennett, Terry Borne, Dorn Crawford, Mary Rose Evans, Ben Finn, Mariano Floro, John Lanning, John Sistarenik, Bob Welch, Mike Zanone
The meeting began shortly after 7:00 PM. The committee resumed its study of flight track development, and approach and departure management, using enlarged maps, aeronautical reference materials, and the advice of attending pilots and air traffic controllers. Distributed items included
• Notes of the Mar 9 meeting, for approval
• Enlarged noise contour maps and plotting tools
• High- and low-altitude aeronautical charts including the SDF area
• Approach plates and standard approach and departure manuals
• A3 handout maps of current and projected noise contours and land uses
Notes of the Notes of the committee’s last meeting were approved. The chair reviewed the major conclusions the committee has reached in this inquiry to date:
North of the airport:
• Off the east runway, arriving and departing on runway heading appears to be the best available initial/final track, since any veer to the west would converge with the west runway heading, and any veer to the east would increase noise in adjoining neighborhoods. Exposure in this quadrant must thus be determined by the degree of runway preference applied.
• Off the west runway, by contrast, a corridor of industrial land use offers potential for an effective noise abatement flight track 10 to 15 degrees west of runway heading. Present procedures apply an 18-degree veer to all departures, but arrivals follow runway heading using available instrumentation. Carefully leveraged through application of necessary navigational aids and control measures, this corridor shows considerable promise for accommodating both arriving and departing traffic without adverse effects.
South of the airport:
• Ongoing acquisition and relocation programs should reduce incompatible land use to an extent that carefully managed routing can relieve remaining problems:
• Elevated areas can escape disproportionate exposure, once we have reasonable estimates of the added impact of elevation in the SDF case, by having designated maneuver procedures that avoid them.
• Navigational aids can improve definition and fidelity of flight tracks south, as well as north, of the airfield. Practical steps that improve avoidance of the Fort Knox restricted area would be particularly valuable.
• Adjoining areas east and west of the airport should be studied for secondary exposure arising from radar ‘downwind’ practices that could be altered with only modest operational impact.
With this overview, the committee returned to available maps, charts and instruments to refine its view of specific navigation-oriented approaches to the issues noted.
The vice chair, Mariano Floro, led further consideration of several of the preceding points using a discussion paper he distributed to the committee, which is attached to these notes. The paper develops rationale for extending radar patterns that guide traffic passing east or west of the airport. It also helps define and detail the various capabilities on-field navigation aids would add to routing and control of approaches and departures. While covered at some length in previous meetings, this material underscores the importance of pursuing this measure as a high priority.
The challenge facing the committee at this point is trying to find the best way to articulate approach and departure routes that would take best advantage of the control measures under discussion. Bob Welch suggested the following description, for example, of a standard approach to runway 17R:
"Whenever the weather is 1000’ ceiling and 3 miles visibility, arrivals will be cleared for an LDA (with glideslope and DME) approach. The approach will be a 10-degree offset from runway heading, with an initial approach fix at 8 DME from the end of the runway."
And for a standard departure,
"After takeoff, turn left to intercept the 17R localizer, and track outbound to the 6 or 7 DME fix prior to any turns on course."
These formulations suggest that navigation reference points that either already exist or could be defined relative to on-site instruments may be more useful than continuing to describe routes based on compass headings and reckoned distances. The committee continues to seek refinement of both concepts and articulation of these measures, and expects to benefit from consultant advice when the analysis reaches that stage.
There was some further discussion of limiting exceptions to contraflow operations, in which aircraft arrive from or depart to the north at night for reasons other than weather. The committee still awaits data showing the origins and nature of these operations, in order to consider potential steps.
The chair proposed that the next meeting be called when additional input can be acquired on optimum definition of flight routes, or data on contraflow exceptions, or both. This was agreed
The meeting adjourned at 9:30 PM.
Navigation Committee Case Study Group
April 6, 2000
The departure and arrival flight track data presented by the Leigh Fisher Associates of the FAR Part 150 Noise Compatibility Study encompasses a variety of traffic. This flight track data shows much information that is both confusing and overwhelming. Under further review, track data from the north identifies a heavy volume of arrivals and departures. However, the traffic presented does not disseminate the difference between VFR and IFR traffic into the Louisville lAP. One can only assume by the logically sequence of tracks where the radar pattern downwinds are and the arrival and departure fixes start. The Navigation committee has identified the air traffic noise from the north as the main priority.
ARRIVALS
The flight tracks to the north show a heavier volume of traffic than the south, we can assume this is true. The ground tracks to the south seem more disciplined than to the north. The group wonders why the tracks down south are more aligned with the runway than the north. This is a puzzling question. If one looks closer to the schematics, the flights outside of the air cargo tracks show a great disparity. The commuter, air carrier, general aviation and military comprise the other component of flights outside the air cargo. The group understands that the operators fly what they are instructed to how and where to fly, and the group understands ATC does not allow free reign over the base turn to final. However, why is there inconsistency with the north and south arrival tracks?
RECOMMENDATIONS
One viable solution we could propose is to increase the radar pattern size to the west, extend this track out to the river, and turn to final past the river. Even though aircraft are vectored from the radar downwind at 4000' to 6000' the increased distance could be compromised as long as the turn to final is extended further out past the Ohio River. In addition, if this procedure is adopted by ATC, all aircraft should fly the same ground track regardless of their aircraft type. This would alleviate the deviations on the base and final leg into Louisville lAP. The noise patterns will still stay the same but in a consistent and tight manner. The main thrust is ensuring a standard is uniformed and within compliance with all operators.
The arrival issue into Louisville addresses several proposals. First priority is in the use of runway 17R only if an alternate approach procedure is adopted. We propose the additions of a Localizer Directional Aid (LDA) and a TACAN/VOR/DME. With these navigational aids on the field, aircraft can fly accurate departures and arrivals into Louisville. The Localizer Directional Aid would be used for runway 17R. This LDA would be offset to give an approach 15 to 20 degrees west one mile off the approach end of runway 17R. (See chart) The group recommends the LDA because it gives both azimuth and glideslope to ensure proper ground track and descent into runway 17R. The reason for the offset of 15 to 20 degrees is the air traffic would be flying over the industrial and rail areas. One recommendation is that the final approach fix be placed passed the river. The group feels that this would avoid a series of neighborhoods that are on final to runway 17R. This procedure is only for high volume and normal weather operations, but if the weather becomes a factor, the use of 17R precision approach will take priority.
The need for an Omni-directional navaid on the field is necessary for departures and arrivals. This takes priority and can ensure a precise ground track is followed on departures. In addition, the availability of a navaid on the field gives many options to making various approaches, standard instrument departures, and arrivals. For instance, if taking off to the north on runway 35L using the same ground track as the offset approach to a specified altitude or distance from the field, operators are able to follow without difficulty. After this distance or altitude, the aircraft would be cleared on course. This ground track would give some relief to those neighborhoods that are in the Old Louisville proximity because during times of takeoffs, high power settings will give off the highest noise decibels. A standard instrument departure such as mention is not difficult to construct nor out of the standard but presents much flexibility. With distance measuring equipment on the airfield, ATC and operators have the flexibility to ensure operators can maintain distances, arcs, and ground tracks.
SUMMARY
Most of the ideas presented are related to the north end of the airfield because of the high volume of traffic, the neighborhoods susceptibility to noise, and the high population to the north. Traffic priority with these proposals could be to either runway depending on the upgrade of procedures and equipment. If new equipment were added on the field, such as the LDA, priority would go to runway 17R/35L. In the mean time, runway 17L would be preferred until such equipment is in place. If runway 17L is utilized strict ATC procedures should be implemented to ensure standard compliance that certain ground tracks are followed. This would alleviate the deviations patterned in the arrival tracks and can give relief to those affected.