[potato3732842]

You can always come up with some pretext to justify things by ignoring the other side of the equation.

How many lives do the man hours spent commuting, or toiling away to afford higher rents waste?

IDK how the math pencils out, but an attempt ought to be made before drawing conclusions.

[Retric]

None? Nobody puts airports inside city centers and metro areas don’t just have dense urban housing. The common solution in many land strapped cities is for airports to rout aircraft over water often by building airports on reclaimed land.

What generally gets areas in trouble is locations that used to be a good get worse as aircraft get larger and the surroundings get built up. The solution is to send larger airplanes to a new airport, but it’s not free and there’s no clear line when things get unacceptably dangerous.

[nostrademons]

San Jose does. You can, in theory, walk to downtown from the airport; it's about an hour and a half via pedestrian trail:

https://maps.app.goo.gl/zhZdA5tWGAKunM2e8

(This is widely considered a misfeature of San Jose - it limits the height of buildings in downtown San Jose to 10 stories because the downtown is directly under the flight path of arriving flights, it limits runway length and airport expansion, and it means that planes and their noise fly directly over key tourist attractions like the Rose Garden and Convention Center. If we ever had a major plane crash like this one in San Jose it would be a disaster, because the airport is bounded by 101 on the north, 880 on the south, the arriving flight path goes right over downtown, and the departing flight path goes right over Levi's Stadium, Great America, and several office buildings.)

[Retric]

There’s roughly a mile of roads, green spaces, and river between the airport and downtown San Jose which an absolutely identical accident would impact. It’s not very wide, but pilots aren’t going to aim for buildings if they can help it.

So while downtown being in the flight path is a risk there was some method to the madness which caused that alignment.

[jonas21]

San Diego's airport, on the other hand, has the a bustling restaurant district, an interstate with frequent bumper-to-bumper traffic, and a dense residential neighborhood all within a mile off one end of the runway -- and a popular shopping area, an elementary school, and a high school within just over a mile from the other end.

In addition, the terrain rises in both directions (so sharply on one side that planes can't use ILS when landing from that direction).

[DiggyJohnson]

The fact that San Diego operates essentially downtown with a single runway is a marvel, even if it does cause issues. I hope they get the tram extension one day.

[Retric]

Agreed, and clearly there’s a bunch of much safer options. The north island air station base is close and almost comically better.

[Johnny555]

The Las Vegas Airport is very close to the strip, surrounded by residential neighborhoods and hotels about 1/4 - 1/2 mile from the airport, and UNLV university is about 1000 feet in a straight line from one of the runways.

[bdamm]

San Jose Airport's walkability and bikability is actually wonderful and I always take the opportunity to walk or bike there when flying into SJC.

[Arainach]

>None? Nobody puts airports inside city centers and metro areas don’t just have dense urban housing.

https://en.wikipedia.org/wiki/Midway_International_Airport

It's hard to project growth. Things build right up to the limit of the airport for convenient access, then the area grows and the airport needs to grow - and what do you do? Seattle-Tacoma is critically undersized for the traffic it gets and has been struggling with the fact that there's physically nowhere to expand to.

[Retric]

Zoning is one option to direct growth, but you can move airports. Chicago is right next to a Great Lake and there’s relatively shallow areas ready to be reclaimed etc.

Obviously you’re better off making such decisions early rather than building a huge airport only to abandon it. Thus it’s called urban planning not urban triage.

[Arainach]

Move them to where? Cities large enough to merit an airport generally either have development which has expanded around them or physical features not conducive to development (mountains, lakes, etc.).

It's easy to say "just build bigger elsewhere" but unless you go dozens of miles out and add hours to every trip to/from the airport there's no options.

And no, "just fill in every body of water" is not an option. It doesn't work at all in many cases, is hilariously expensive in all cases, and has enormous environmental impact.

[Retric]

I’m specifically suggesting using reclaimed land if they relocated the airport because the cost seems to work out for Chicago, though obviously an in depth analysis is necessary. Still just looking at the depths combined with lakes not having the downsides of open oceans makes it promising. Unfortunately we’re talking about a huge airport so moving anywhere gets incredibly expensive.

The ultimate reason so many cities use land reclamation for airports is open water does not lose property value by being near the airport. Thus a given greater metropolitan area regains not just the physical land of the airport but the increased property value from all that land that’s no longer next to an airport.

[potato3732842]

>Zoning is one option to direct growth

My magic crystal ball named "the past 50yr of history" says it is unlikely to be the success you envision.

[DiggyJohnson]

There’s a real convenience to an airport not being 50 minutes away

[eitally]

Congonhas (the original Sao Paulo airport) is right in the middle of the city.

There was a significant crash there in 2007: https://en.wikipedia.org/wiki/TAM_Airlines_Flight_3054

[matt-p]

In all honesty most countries in europe have at least one airport in a city centre. I mean look at lisbon, RKV, BHD/LCY (even glasgow,LHR to some extent), BMA, NCE.

[alexjplant]

I live in San Diego and can watch planes come and go from my apartment rooftop. I've also walked to and from the airport to stretch my legs before and after flights.

Somewhere I have a GoPro video of me on my motorcycle waiting for a freight train at a crossing in traffic while a 747 flies overhead ("Planes, Trains, and Automobiles"). It's a pretty transportation-dense area.

[vel0city]

> Nobody puts airports inside city centers and metro areas don’t just have dense urban housing

Ever see Dallas Love Field?

https://maps.app.goo.gl/A94EdexYwfpyeMxa7

Lots of airports are pretty much immediately adjacent to their city centers.

[gwbas1c]

> The common solution in many land strapped cities is for airports to rout aircraft over water.

That works in costal areas, but not inland.

There's no large body of water near the Louisville airport.

[Retric]

The Ohio River is a large body of water fairly close if someone was going to relocate Louisville airport.

[WorldMaker]

The Ohio River is a mile wide at Louisville, but that still doesn't wide enough to classify it "large body of water", especially because it is a river that moves relatively quick for its width and then hits falls/rapids just downstream of Louisville.

But also there's a lot of urban and suburban development you'd have to displace to even consider moving the airport near the Ohio River for most miles both up and down stream of Louisville.

[Retric]

Tradeoffs. Physical land under the airport is lost either way, but land near the old airport becomes more useful where the river itself couldn’t have buildings in either situation. Thus moving it near a river or other large body of water is a long term net gain.

As to a crash, ditching into an industrial area isn’t significantly worse for the passengers than ditching into a set of rapids, but the rapids are far better for the general public.

[WorldMaker]

To be fair to this specific airport, the industrial area South of the airport is almost entirely UPS Airlines facilities. The safety hazard posed by the UPS Airlines flight crash was primarily to UPS Airlines warehouses and warehouse workers. They made their own tradeoffs in this case of what they placed close to their own runways (including apparently they had a fuel recycling plant not far from the crash line that made firefighting more complicated). Sure it's still very different from a large body of water, but it's also certainly not like the land was entirely a general usage industrial area either.

Had the crash happened in a different direction there might be other complaints, sure, but even airports with large bodies of water neighboring them only generally neighbor a side or two.

[johann8384]

It's not even a mile wide here. The widest spot I measured just east of the falls was 0.75, at Utica it is 0.34 and at Westport it's 0.39.

[mywittyname]

I don't think effectively damming (alternatively, rerouting) the Ohio River is a solution to relocating an airport in Louisville. That's a wildly ambitious undertaking compared to most other land reclamation projects.

Yeah, the terrain around Louisville poses a challenge for placing an airport, but they could do like Cincinnati does, and have their airport located across the river. Or place it between Frankfurt and Louisville. Or do like Pittsburg and make the terrain flat enough for an international airport.

[gwbas1c]

That's a thimble: When I zoomed out on the map the airport was huge and the river just a few pixels wide. Otherwise I wouldn't have made the comment I made.

[Retric]

Airports are far larger than aircraft, which enter and leave from the end of runways.

Rivers have a nice property where they tend to be the lowest thing around because water flows downhill and are quite long. For approaches from other directions half the time you end up crossing the river at some angle which acts as a buffer zone, thus reducing the total land lost as a buffer zone.

[wongarsu]

Inland it can work if you have a river. London City Airport would be an example

[ilamont]

> Nobody puts airports inside city centers

Taipei Songshan, Boston Logan and the old Hong Kong Kai Tak to name a few.

[Retric]

Boston Logan is surrounded by water to the point only one end of a single runway isn’t aimed directly at water soon crosses water. The city center requires crossing a bridge. Taipei is a little worse but its only runway is going next to a river here and aimed at a park on each side.

Hong Kong Kai Take would be a solid example except it closed in 1998 because of how the city grew. Look at maps from 1950 and it doesn’t look like a bad location for a small airport.

[ilamont]

> The city center requires crossing a bridge.

It actually requires using tunnels or a boat. I used to drive a cab and the I93 + Callahan/Sumner tunnel route was hellish. The Big Dig helped a lot, although sometimes that can get pretty backed up too.

> Look at maps from 1950 and it doesn’t look like a bad location for a small airport.

Generally, airports that are close to major urban centers were developed prior to 1950, including all 3 examples named. Songshan was opened during Taiwan's colonial period as the “Matsuyama Airdrome” serving Japanese military flights (https://www.sups.tp.edu.tw/tsa/en/1-1.htm).

For bigger cities with these old central airports, larger airports were opened later in many cases. I don't think that will ever happen in Boston, although satellite airports in neighboring states like "Manchester-Boston" or TF Greene in Rhode Island try pretty hard.