Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Someone wiser please correct me if I’m wrong, but I believe north flow means better safety and efficiency because you’re not using the river visual (manual flying) landing that direction. It makes sense that ATC would use it as the default absent weather constraints.

Not all flights from the north use a visual approach; when the weather sucks but they have to come in from that way, it's a GPS assisted landing with a slightly different plan.

And like a PP said, the air traffic is coordinated between all 3 airports in the area, so apparently south flow just works better for that coordination.

There are four southbound approach procedures. For those who are interested in details: the procedures are named “River Visual,” “RNP,” “LDA Y,” and “LDA Z.” If you google those terms you can find them on the FAA website. The good procedures are River Visual and RNP, which take planes over the river. River Visual requires the pilot to navigate visually, so it can only be used when visibility is at least 3 miles and cloud ceiling is at least 3500 feet. It can be used at night. RNP is an instrument approach but it requires advanced navigation, the FAA says that only 30% of the planes using DCA are capable of doing that approach.

The bad approach, LDA Y, has pilots fly straight in from outside the beltway on a compass bearing of 147 degrees directly to the airport. When they get to a point on the banks of the Potomac directly opposite GDS (38.903017 N, 77.086772, W) they can either continue straight or jog left to line up their approach. They have to maintain 3,000 feet to that point.

The terrible approach is LDA Z. They fly in on a compass bearing of 145 degrees to a point above Arizona Avenue and Sherier Place. They have to maintain 1700 feet to that point. Then they head to a point above the center of the Potomac by Georgetown (38.903519 N 77.075661 W), they have to maintain 1100 feet to that point. This is the flight path we’ve all come to know and hate. Note that the altitude is above sea level, when they fly more toward Loughborough they could be 900’ off the rooftops.

The LDA approaches have planes fly directly over residential neighborhoods at low altitudes. The FAA doesn't seem to care if planes deviate from the procedure or if they maintain minimum altitudes. The FAA claims that River Visual should be used unless atmospheric conditions allow, although planes often fly one of the LDA procedures when visibility is perfect, particularly late at night.

This is fascinating - thanks for posting.

I'm the PP who lives just south of the airport and from our end noise is much louder when we have takeoffs vs. landings. Is the complaint on the north end about landings? Because from a noise management standpoint I would be thrilled for you guys to "solve" the loud approaches problem by just having the takeoffs all day long whenever weather permits.

I live north of the airport, and when they're flying northbound I get the 5:45 AM United flight to Chicago which sounds like it's going to come through my window.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Someone wiser please correct me if I’m wrong, but I believe north flow means better safety and efficiency because you’re not using the river visual (manual flying) landing that direction. It makes sense that ATC would use it as the default absent weather constraints.

Not all flights from the north use a visual approach; when the weather sucks but they have to come in from that way, it's a GPS assisted landing with a slightly different plan.

And like a PP said, the air traffic is coordinated between all 3 airports in the area, so apparently south flow just works better for that coordination.

There are four southbound approach procedures. For those who are interested in details: the procedures are named “River Visual,” “RNP,” “LDA Y,” and “LDA Z.” If you google those terms you can find them on the FAA website. The good procedures are River Visual and RNP, which take planes over the river. River Visual requires the pilot to navigate visually, so it can only be used when visibility is at least 3 miles and cloud ceiling is at least 3500 feet. It can be used at night. RNP is an instrument approach but it requires advanced navigation, the FAA says that only 30% of the planes using DCA are capable of doing that approach.

The bad approach, LDA Y, has pilots fly straight in from outside the beltway on a compass bearing of 147 degrees directly to the airport. When they get to a point on the banks of the Potomac directly opposite GDS (38.903017 N, 77.086772, W) they can either continue straight or jog left to line up their approach. They have to maintain 3,000 feet to that point.

The terrible approach is LDA Z. They fly in on a compass bearing of 145 degrees to a point above Arizona Avenue and Sherier Place. They have to maintain 1700 feet to that point. Then they head to a point above the center of the Potomac by Georgetown (38.903519 N 77.075661 W), they have to maintain 1100 feet to that point. This is the flight path we’ve all come to know and hate. Note that the altitude is above sea level, when they fly more toward Loughborough they could be 900’ off the rooftops.

The LDA approaches have planes fly directly over residential neighborhoods at low altitudes. The FAA doesn't seem to care if planes deviate from the procedure or if they maintain minimum altitudes. The FAA claims that River Visual should be used unless atmospheric conditions allow, although planes often fly one of the LDA procedures when visibility is perfect, particularly late at night.

This is fascinating - thanks for posting.

I'm the PP who lives just south of the airport and from our end noise is much louder when we have takeoffs vs. landings. Is the complaint on the north end about landings? Because from a noise management standpoint I would be thrilled for you guys to "solve" the loud approaches problem by just having the takeoffs all day long whenever weather permits.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Someone wiser please correct me if I’m wrong, but I believe north flow means better safety and efficiency because you’re not using the river visual (manual flying) landing that direction. It makes sense that ATC would use it as the default absent weather constraints.

Not all flights from the north use a visual approach; when the weather sucks but they have to come in from that way, it's a GPS assisted landing with a slightly different plan.

And like a PP said, the air traffic is coordinated between all 3 airports in the area, so apparently south flow just works better for that coordination.

There are four southbound approach procedures. For those who are interested in details: the procedures are named “River Visual,” “RNP,” “LDA Y,” and “LDA Z.” If you google those terms you can find them on the FAA website. The good procedures are River Visual and RNP, which take planes over the river. River Visual requires the pilot to navigate visually, so it can only be used when visibility is at least 3 miles and cloud ceiling is at least 3500 feet. It can be used at night. RNP is an instrument approach but it requires advanced navigation, the FAA says that only 30% of the planes using DCA are capable of doing that approach.

The bad approach, LDA Y, has pilots fly straight in from outside the beltway on a compass bearing of 147 degrees directly to the airport. When they get to a point on the banks of the Potomac directly opposite GDS (38.903017 N, 77.086772, W) they can either continue straight or jog left to line up their approach. They have to maintain 3,000 feet to that point.

The terrible approach is LDA Z. They fly in on a compass bearing of 145 degrees to a point above Arizona Avenue and Sherier Place. They have to maintain 1700 feet to that point. Then they head to a point above the center of the Potomac by Georgetown (38.903519 N 77.075661 W), they have to maintain 1100 feet to that point. This is the flight path we’ve all come to know and hate. Note that the altitude is above sea level, when they fly more toward Loughborough they could be 900’ off the rooftops.

The LDA approaches have planes fly directly over residential neighborhoods at low altitudes. The FAA doesn't seem to care if planes deviate from the procedure or if they maintain minimum altitudes. The FAA claims that River Visual should be used unless atmospheric conditions allow, although planes often fly one of the LDA procedures when visibility is perfect, particularly late at night.

WHO ARE YOU? Do you work at the airport? The FAA? You're an expert on these issues - thank you for sharing! So incredibly fascinating.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Someone wiser please correct me if I’m wrong, but I believe north flow means better safety and efficiency because you’re not using the river visual (manual flying) landing that direction. It makes sense that ATC would use it as the default absent weather constraints.

Not all flights from the north use a visual approach; when the weather sucks but they have to come in from that way, it's a GPS assisted landing with a slightly different plan.

And like a PP said, the air traffic is coordinated between all 3 airports in the area, so apparently south flow just works better for that coordination.

There are four southbound approach procedures. For those who are interested in details: the procedures are named “River Visual,” “RNP,” “LDA Y,” and “LDA Z.” If you google those terms you can find them on the FAA website. The good procedures are River Visual and RNP, which take planes over the river. River Visual requires the pilot to navigate visually, so it can only be used when visibility is at least 3 miles and cloud ceiling is at least 3500 feet. It can be used at night. RNP is an instrument approach but it requires advanced navigation, the FAA says that only 30% of the planes using DCA are capable of doing that approach.

The bad approach, LDA Y, has pilots fly straight in from outside the beltway on a compass bearing of 147 degrees directly to the airport. When they get to a point on the banks of the Potomac directly opposite GDS (38.903017 N, 77.086772, W) they can either continue straight or jog left to line up their approach. They have to maintain 3,000 feet to that point.

The terrible approach is LDA Z. They fly in on a compass bearing of 145 degrees to a point above Arizona Avenue and Sherier Place. They have to maintain 1700 feet to that point. Then they head to a point above the center of the Potomac by Georgetown (38.903519 N 77.075661 W), they have to maintain 1100 feet to that point. This is the flight path we’ve all come to know and hate. Note that the altitude is above sea level, when they fly more toward Loughborough they could be 900’ off the rooftops.

The LDA approaches have planes fly directly over residential neighborhoods at low altitudes. The FAA doesn't seem to care if planes deviate from the procedure or if they maintain minimum altitudes. The FAA claims that River Visual should be used unless atmospheric conditions allow, although planes often fly one of the LDA procedures when visibility is perfect, particularly late at night.

WHO ARE YOU? Do you work at the airport? The FAA? You're an expert on these issues - thank you for sharing! So incredibly fascinating.