Passenger Trains > Blended braking P42DC

Hey everybody,

I have a question about braking Amtrak Trains.
I´ve always wondered about the braking procedure of an Amtrak Train (hauled by a P42DC) while stopping at a station. Does the engineer always use blended braking (combination of air braking and dynamic braking)? And if so, which brake does the engineer activate first? The air brake or the dynamic brake? I´ve seen Coast Starlight Trains coming into the station really fast. I think this is only possible with blended braking, isn´t it?

Thank you!

ontherail55

 

An engineer will use whatever braking method is available to him based on the type of the train, what we call mixed or non mixed. Also depends on what type of stop or slowing down is needed, topography and other conditions.

The blended is activated by using the automatic brake valve and not bailing off. Usually when I have a consist with 2 or more p42s, I will take a minimum regular set 1st (bail off loco brakes), and then not bail off my further reductions and activate the blended braking, what we call stretch blending. The P42s don't like doing regular blending together as they tend to fight each other and can make train handling rough.

The difference between a mixed and non mixed consist is that a non mixed consist does not have more than one non revenue car, like a bag, deadhead or PV car. Both of those types of consists allow for dynamic braking, blended braking and braking with no power applied. However, only a mixed consist allows for braking with power applied in addition to all that.

Posted from Android

KV1guy Wrote:
-------------------------------------------------------
> An engineer will use whatever braking method is
> available to him based on the type of the train,
> what we call mixed or non mixed. Also depends on
> what type of stop or slowing down is needed,
> topography and other conditions.
>
> The blended is activated by using the automatic
> brake valve and not bailing off. Usually when I
> have a consist with 2 or more p42s, I will take a
> minimum regular set 1st (bail off loco brakes),
> and then not bail off my further reductions and
> activate the blended braking, what we call stretch
> blending. The P42s don't like doing regular
> blending together as they tend to fight each other
> and can make train handling rough.
>
> The difference between a mixed and non mixed
> consist is that a non mixed consist does not have
> more than one non revenue car, like a bag,
> deadhead or PV car. Both of those types of
> consists allow for dynamic braking, blended
> braking and braking with no power applied.
> However, only a mixed consist allows for braking
> with power applied in addition to all that.
>
> Posted from Android

Always enjoy the professional and detailed insight from a current hogger. Thanks!

exactly.  thanks kv1guy for that explanation............

66

KV1guy Wrote:
-------------------------------------------------------
> An engineer will use whatever braking method is
> available to him based on the type of the train,
> what we call mixed or non mixed. Also depends on
> what type of stop or slowing down is needed,
> topography and other conditions.
>
> The blended is activated by using the automatic
> brake valve and not bailing off. Usually when I
> have a consist with 2 or more p42s, I will take a
> minimum regular set 1st (bail off loco brakes),
> and then not bail off my further reductions and
> activate the blended braking, what we call stretch
> blending. The P42s don't like doing regular
> blending together as they tend to fight each other
> and can make train handling rough.
>
> The difference between a mixed and non mixed
> consist is that a non mixed consist does not have
> more than one non revenue car, like a bag,
> deadhead or PV car. Both of those types of
> consists allow for dynamic braking, blended
> braking and braking with no power applied.
> However, only a mixed consist allows for braking
> with power applied in addition to all that.
>
> Posted from Android

Hi KV1guy,

that's very interesting and gives me a detailed insight. I am a hobby railroader, not professionally. But that's great information to do it correctly in Train Simulator. Yeah, it's not the same as the real thing. But good for me.

I am from Germany, but Amtrak is my life.

May I ask, which routes you cover?

Thanks
Ontherail55

As a freight guy....I would probably not be so good at pax service...but I could probably get by NOT activating any blended feature....unless I am in Dynamic already and decide to add some air....but if I am stretching...I am not going to touch the dynamic...I don't want to bunch it up....but IF I am bunched and have enough momentum to reach my stopping point...I'll stay that way...stop it at the last bit with a touch of air...and since I have to use air to anyway to condition the brakes...

Must be nice. We're not allowed to stretch brake where I'm at. Which would very much help with ride quality for passengers. 

jeremykhn Wrote:
-------------------------------------------------------
> Must be nice. We're not allowed to stretch brake
> where I'm at. Which would very much help with ride
> quality for passengers. 

We are supposed to avoid it if we have dynamics...but failing that we can stretch but cannot use more than 4 notch in power...and should reduce power as train slows against the brakes. There are some trains which are heavy but short on which they will overlook stretch braking if they are sure you are good doing it.