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dbdb

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  1. dbdb

    Saskatoon Updates

    Transit manager Jim MacDonald offers some good insight into why Saskatoon will not be in the market for used buses in this 2015 Star Phoenix article and a followup article the next day. For those who don't want to read it, the TL;DR is a new bus costs $1.40/1000km to maintain while an old bus costs $5.00/1000km.
  2. dbdb

    Saskatoon Updates

    Saskatoon's problem was a the culmination of decades of failing to adequately fund transit capital renewal. Transit only had budget to replace a couple vehicles each year, less than the rate at which they were reaching end of life. For a number of years they put that little bit of money into cosmetic refurbishing to get a few more years out of several buses instead of buying new. The fleet just got older requiring more maintenance, a shortage of mechanics made it harder to keep up with maintenance and no money to replace equipment that was beyond repair left no choice but to buy old equipment being sold for scrap from other jurisdictions. The crisis in 2014 where routes had to be cancelled woke up city council leading to new management in Transit and more funding. Some recent federal money allowed an accelerated fleet renewal. There is no reason for Saskatoon Transit to buy anything but new equipment.
  3. dbdb

    Amtrak

    No wonder Amtrak is losing big money on long haul. They have no idea what this will cost, the article didn't suggest what the demand for the route might be. If I were in charge of Amtrak I'd make a deal with Via to essentially sell throughway itineraries anywhere on the Via network from Windsor and run a throughway coach to connect Amtrak in Detroit with Via in Windsor, no new tunnel, no new right of way, no new equipment Customs is handled by the contractor running the bus connection so there's very little cost to add add essentially any destination on the Quebec City - Windsor corridor. Via wins, Amtrak wins, spend the money to fix bottlenecks in the domestic network.
  4. dbdb

    Saskatoon Updates

    Saskatoon has recovered from the fleet crisis of 2014 replacing nearly all of the less reliable pre-2000 vehicles over the past few years. With a larger more reliable fleet there is no need for used buses.
  5. dbdb

    Boeing 737 MAX

    It seems that data was just released. CBC had a report on the weekend citing other incidents where pilots reported problems with MCAS including one calling training "criminally insufficient". The Seattle Times report has a robust detailed analysis of the design, certification process and likely issues.
  6. dbdb

    Boeing 737 MAX

    It seems like the press finally decided over the weekend the max grounding was sufficient to justify a reporter doing some actual factual investigation searching incident reporting databases in Canada and the U.S. There have been several complaints about the training from pilots who encountered surprises in flight.
  7. dbdb

    Boeing 737 MAX

    The MAX mostly is a normal plane. They opted to put bigger engines on the 737 instead of designing a new narrow-body aircraft. The larger engines mean a few changes like positioning the engines a bit different and increasing the height of the landing gear a bit. MCAS was supposed to compensate for those changes. A friend who follows some aviation vlogs said that Boeing didn't originally plan to have MCAS but instead added in response FAA insistence. I haven't been able to find a credible source to corroborate that claim so it may or may not be true.
  8. dbdb

    Boeing 737 MAX

    We're still waiting on CVR and FDR data from the Ethiopian flight. Once investigators have that I'm sure will get a more clear picture if there is a systemic issue to be concerned with.
  9. dbdb

    Canadian Rail Accidents

    If I understand how the brakes work, they are engaged by air pressure from a reservoir on each car which is divided into two parts for service braking and emergency braking. Before the train gets underway, the brake system is pressurized and the reservoirs fill with air. When air pressure along the train is slowly released below a certain pressure service braking is engaged. When all the pressure in the air line is rapidly released the emergency reservoir will apply additional force to the brakes. Over time air leaks from the brake system on each car. As air pressure in the reservoirs drops the force of the brakes drops. On perfectly level ground that might not be a big deal but on a slope gravity opposes the braking force. The steeper the slope and the heavier the car the greater the force due to gravity. As air leaks from the system eventually the braking force reduced to less than what's needed to oppose the force of gravity and the train will begin to roll. As the train picks up speed braking forces are not just opposing the static force of gravity but the kinetic force which takes even more braking force to overcome. Now, if I understand the system correctly the only way to re-engage the air brakes on the cars to stop the train is to re-pressurize the air line to refill the reservoirs to full pressure releasing the brakes then re-engage them by releasing the pressure -- slowly for service brake or rapidly for emergency brakes. There are two things conspiring it takes a long time to recharge the brake system and during that time the train is accelerating so there is an increasing amount of kinetic energy for the brakes to stop. In an extreme scenario the speed increases so the kinetic energy is beyond what the air brake system can stop -- this happened in the Cajon pass derailment featured on an episode of Mayday. What likely happened in the case of the CP derailment, and now I get why the TSB was particular about not calling it a runaway, is the train simply ended up going too fast for sharp curves accelerating while the engineer was desperately trying to get the brake system up to pressure to control the speed of the train. Until the brake system was fully pressurized all that would have been available to slow or stop the train would be the independent and dynamic brakes on the 3 locomotives which would be woefully insufficient. While the distributed locomotives may have helped get pressure to the brake system faster it wasn't fast enough for a train accelerating on a steep slope heading toward a sharp curve just minutes away. The lesson is don't park a heavy train on a steep slope for a long time relying on air brakes. With some statistics predicting the rates at which rail car air brakes lose pressure engineers (the white collar kind) could come up with an equation or model to predict what the maximum safe time a train could stop on a given slow with air brakes. Hopefully this incident will trigger the TSB and Transport Canada to do the research and come up with that so dispatchers and engineers can make better informed decisions in similar circumstances.
  10. dbdb

    Canadian Rail Accidents

    Quick question for smallspy or one of the other railroaders on here. I was discussing the circumstances of the CP derailment with a friend the other day and he mentioned something that I didn't know that I think was confirmed in an article I read today on the CP derailment. I ready that air dryers are used in the winter and it significantly slows air flow to pressurize the brake system. My friend says a relative who is a CN conductor mentioned it can often take an extremely long time, as much as an hour get the system up to enough pressure to release the brakes in the winter. Is that true?
  11. dbdb

    Canadian Rail Accidents

    The TSB representative at the press conference yesterday said they were based out of Calgary but the engineer and conductor were experienced in the territory. It surprised me the TSB has already made statements suggesting they've already ruled out the actions of the accident crew as a cause. They must have some pretty good evidence to the contrary especially when they're so careful to avoid the term "runaway".
  12. dbdb

    Canadian Rail Accidents

    The Transportation Safety Board investigation page for more details: http://tsb.gc.ca/eng/enquetes-investigations/rail/2019/r19c0015/r19c0015.asp Sounds like the air brakes failed after a couple hours sitting on a steep grade. The findings should be interesting.
  13. Dash-cam footage of the start of a train derailing at a grade crossing near Saskatoon: https://www.ctvnews.ca/canada/dashboard-video-captures-moment-52-car-train-derails-near-saskatoon-1.4264158 That's something you don't see everyday.
  14. dbdb

    VIA Rail Canada

    That's situation with a lot of a lot of today's companies lead by people with business degrees who have great expertise in finance and management but no foundational experience or education on the good or services the company offers. Via may be terrible at keeping a schedule but at least they know their business lives and dies by customer experience and in my experience they do a pretty good job. Good customer experience also depends on knowing what you can deliver and setting reasonable expectations. While it's unfortunate they're dropping 1 trip per week, all things considered it's probably the right move for the short term. I expect once CN completes more capital improvements through the prairies over the next couple/few years we'll see improvements to Via service between Toronto and Edmonton. Making an inference from Via's summer schedule reduction on the Canadian my bet is CN will be announcing a substantially bigger siding expansion/double tracking plan for 2019 probably resulting in a summer of chronically delayed Via #1/#2 trains.
  15. dbdb

    Amtrak

    There are a couple of flaws in the Times Union story. First, if the cars separated, I would expect the brakes would begin to engage once air pressure is lost so the student credited with saving the day probably didn't actually do anything that wasn't already happening automatically. Second, the lady who claims the separated car had a very wrong perception of the event, the separated car could not have been accelerating if it was separating from the rest of the train. The article on CBC has a witness account that makes more sense; a pop, a hiss, some burning followed by cold air -- coupler breaks with a pop, cars begin to separate and air line disconnects with a hiss, electrical line is arcs as it's ripped off (burning smell) and cold air once the gangway connection opens.
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