That’s certainly part of it, but the LLV is also a MUCH cleaner, simpler design. All these modern replacement candidates look like they were styled by the guy who styled the new Civic Type-R. Just WAY too busy, and ugly as a result.

Look, I’m a huge proponent of “function over form,” but I’m also a huge proponent of not making vehicles that are expected to be long-lasting, and commonplace absolutely BUTT-UGLY.

The same thing happened with the Nissan NV-whatever replacement to the yellow cab. An opportunity to make a marked improvement in the…

I mean, the only time it would really be obstructing the driver’s vision is on straights... and even then only well before the corners. Once you even get near a corner, you are looking into the corner, if not past it. So for the vast majority of the time, it won’t be blocking your view anyway.

This isn’t about redundancy. Nothing failed improperly here. This was user error, and a vehicle operating as designed. I’m not sure what you’re wanting to see out of a multi-input valve. At the end of the day, you don’t want brakes to lock up just because you lose electrical power.

You don’t want the brakes to apply in the case of a power failure, though. Think about your personal car. If you lose all electrical power, do the brakes automatically apply? Absolutely not. That would be incredibly dangerous. The last thing you want for a bus is for the parking brake to suddenly apply itself,…

Transit buses don’t even have a “Park” mode for the transmission. They only have Forward, Neutral, and Reverse. So basically he left it in neutral and stepped off the bus. Big fail on the part of the operator.

You’re completely misunderstanding what happened here. That bus is no different than any other bus, and it works exactly in the way you described. In the event of a tank rupture, line rupture, pump failure, or any other failure that results in a loss of air pressure, the brakes would have engaged to bring the vehicle…

To be fair. They could have also jumped in the seat and just slammed on the REGULAR brakes!

Nope. It’s a purely mechanical mechanism. It isn’t an electronic button you press. It’s a giant yellow button that’s really hard to press (disengage the brake) and then pops back out quite aggressively when you pull on it (to engage the brake.)

You’ve lost me.

Transit buses do too. It’s a second knob right next to the parking brake knob that allows you to use a reserve air supply to temporarily disengage the parking brake in order to move the vehicle :)

Correct. Again, though, this incident was due to a loss of electrical power, not air pressure.

We aren’t talking about a loss of air pressure. We are talking about a loss of power (electricity) as in what occurred in this case.

To answer your initial question, though, since I never really got around to it, air brake equipped buses are fail-safe in the same way as trains. They use air pressure to RELEASE the parking brake shoes, so a loss of air pressure from a severed line, or a failed tank or valve or pump or whatnot, will cause the brakes…

No, actually. What if the power cuts out while the bus is moving? Do you want the brakes to suddenly slam on at full force, throwing all the passengers out of their seats, and causing an accident behind you?

Not every single scenario is deserving of this kind of a fail-safe mechanism. If a vehicle loses electrical…

They ARE fail-safe. They aren’t dumb safe. This guy left the seat without engaging the brake. The only failure was on the part of the bus operator. If you are driving your car, and the electrical system cuts out, would you want the brakes to slam on? Nope! Nothing “failed” here. The operator was asked to “power cycle”…

Yeah, the interlock system is basically to prevent the bus from rolling forward as passengers are boarding/alighting if your foot slips off of the brake. It isn’t really an “emergency stop the bus from moving if all hell breaks loose” system. It has a very specific purpose only, which is to prevent you from pissing…

Some transit agencies have the driver’s area separated, but the door wouldn’t have been locked since the operator was outside of the vehicle. Yes, it is a bright yellow button, but on these buses it is sometimes located on the left side of the driver’s area, down beside the seat... so you can’t necessarily even see it…

Would you want your car to slam on the brakes if it lost power? The power loss isn’t the problem. The fact that the driver left the seat without engaging the parking brake is the problem.

Yes, it would have worked. It is indeed pneumatic.
Source: I used to drive these things.