• Even more of a reason for putting more money into passenger rail.

  • General discussion of passenger rail systems not otherwise covered in the specific forums in this category, including high speed rail.
General discussion of passenger rail systems not otherwise covered in the specific forums in this category, including high speed rail.

Moderators: mtuandrew, gprimr1

  by scratchyX1
 
https://www.washingtonpost.com/business ... story.html
Lest you think air travel couldn’t possibly get more miserable, climate change is here to prove you wrong.

Just as extreme heat makes people sluggish and unproductive at best, and threatens human life at worst, it also makes flying airplanes much more difficult. Hot air is less dense than cold air, its molecules zipping around at higher speeds, meaning planes have less lift when the mercury rises. That makes it harder for them to take off and stay aloft.
  by eolesen
 
Nothing but some alarmist rubbish from a climate activist.

Summer temps and payload restrictions are really only an issue at places like Albuquerque, Las Vegas, Tucson and Phoenix.

And that's nothing new. It's been an issue for the 35 years I've been in commercial aviation.
  by Ken W2KB
 
eolesen wrote: Thu Aug 03, 2023 4:33 pm Nothing but some alarmist rubbish from a climate activist.

Summer temps and payload restrictions are really only an issue at places like Albuquerque, Las Vegas, Tucson and Phoenix.

And that's nothing new. It's been an issue for the 35 years I've been in commercial aviation.
Especially claiming a problem to "stay aloft". Longer takeoff roll may on very hot days affect a few very shorter runway airports at higher elevations, but once aloft not an issue, especially at the altitudes at which airliners cruise where the air temperature is far lower than the surface and a few degrees of temperature is essentially irrelevant.
  by bridpath
 
As those of you who fly (and are old) might know/remember, a significant number of commercial airports served by major airlines long ago were often restricted even on good weather days because of runway length. Key West was used by 727s and DC9s at 4,800 feet; Portland, Maine at a one-time 6,800 was problematic for the same on hot, humid days (and that's going back more than 50 years for me). New Bedford, MA at 5,000 feet length could be an issue for Northeast, then Delta, DC9s. Representative examples only, of which many more might be cited.

Density altitude has always been a "thing" for anyone who flies, either professionally or GA, but it was never the single reason for weight restriction at a number of airports.
  by west point
 
bridpath wrote: Fri Aug 04, 2023 2:22 pm Density altitude has always been a "thing" for anyone who flies, either professionally or GA, but it was never the single reason for weight restriction at a number of airports.
There is also a max temp for operating jet engines. Usually 122 F ( 150 C ) Experience has shown that the engines will exceed hot section limits.
  by wigwagfan
 
scratchyX1 wrote:Lest you think air travel couldn’t possibly get more miserable, climate change is here to prove you wrong. Just as extreme heat makes people sluggish and unproductive at best, and threatens human life at worst, it also makes flying airplanes much more difficult.
I guess thermal expansion of rails has magically gone away...our local light rail system has to reduce speeds in high temps, all the way down to 25 MPH; our "commuter rail" "system" fully shuts down over 95 or 100 degrees.

Never heard of our airport shutting down, or reducing aircraft speeds...and of course, the trusty ol' buses that the railfans hate because "oh God, General Motors killed the Streetcar Lines" work at regular speeds without any issues, 55 MPH on the freeway.
  by ChesterValley
 
Eh, I don't think that the MTOW will be that much of an impact. Jet engine operating temperatures and the density of air issue can be mitigated by less payload so its not *critical*. The bigger thing will be the cost of fuel increase from refineries slowing down (which is more influenced by the Saudi's than global warming at this point) but most of all the intensification of storms will be far more disruptive
  by electricron
 
Which is the more imprtant rail to put public funds in? I strongly suggest rail transit. Far more riders will ride local rail transit than commuter or intercity trains.
The point I am making is that the existing slow Amtrak services is not where we should be putting huge amounts of Federal funds. That's the last place Federal funds should go.
If the trains are slow, local transit is the way to go. Only f the trains are very fast should the Feds should funds .
People demand a state-of -the-art intercity train system, not mediticity.
  by wigwagfan
 
scratchyX1 wrote: Tue Aug 08, 2023 8:29 pm How are morraco and other hot climate countries able to run rail with out these issues?
Ask them when the temperatures drop closer to freezing. Yup, same problem in reverse.
  by west point
 
west point wrote: Fri Aug 04, 2023 8:40 pm
bridpath wrote: Fri Aug 04, 2023 2:22 pm Density altitude has always been a "thing" for anyone who flies, either professionally or GA, but it was never the single reason for weight restriction at a number of airports.
There is also a max temp for operating jet engines. Usually 122 F ( 50 C ) Experience has shown that the engines will exceed hot section limits.
  by eolesen
 
scratchyX1 wrote:How are morraco and other hot climate countries able to run rail with out these issues?
They schedule more flights in the early morning and late afternoon/evenings.

It's one of the reasons that Dubai as a long distance connecting Hub operates almost exclusively at night, and departures between noon and 6:00 p.m. are very few compared to 6:00 p.m. to noon.

Sent from my SM-S911U using Tapatalk

  by Arborwayfan
 
electricron wrote: Wed Aug 09, 2023 9:49 am Which is the more imprtant rail to put public funds in? I strongly suggest rail transit. Far more riders will ride local rail transit than commuter or intercity trains.
I kind of agree. An awful lot of total miles driven, fuel used, roads built are for people commuting alone in cars, on routes that stay the same for months or years, over short distances where speed is not as much of an issue, through congested areas where frequent transit can be made faster than driving, to places where parking is hard or expensive. Lots of bang for buck with transit.

Plus, really good transit tends to mean fewer cars per capita: more no-car households, more one-car households. And people without cars are more likely to ride intercity trains, which makes those more likely to get investments. And people are less likely to want to arrive with their car in places that have great transit: more potential intercity train pax again.

I don't actually buy the idea that subsiding more frequent trains on slowish corridor routes is the waste electricron says it is. Not everyone is choosing based on speed. Convenience matters, too. A fourth frequency from Champaign to Chicago, for example, would probably increase passenger traffic substantially just by making train travel more flexible. (Maybe that's a case for very nice buses running every hour rather than four trains a day...)
  by electricron
 
HaleyLawrence wrote: Wed Aug 16, 2023 9:23 pm My personal feeling is that sometimes some high traffic areas don't have their trains set to frequent enough, so maybe something could be set based on the amount of people... Of course I'm just saying..
Check out youtuber City Nerd and his top 10 city pairs for High Speed Rail. Only the NEC city pairs scored higher than 20, Dallas to Houston and Miami to Orlando scored around 10, just about everything else scored less than 2.
He used a gravity model based on both city populations, divided by the distance between them in miles squared, with an adjustment based on time (closer to 2.5 hours heavily favored. His reasoning is, less than that driving gains, more than that airplanes gain market share. Why build a HSR network that can not fill all the trains it needs to run to compete with planes and cars? He explains it all very well.
Agree or disagree with him or not, he is using population as a measure to rank these c9ity pairs. If a train can not make the trip in less than 3 hours, that train should end.