Kids pulling open air powered sliding doors and what protection (if any) there is to stop this

[Bletchleyite]

This area on a 150/1 (the only 150s where the crew door isn't interlocked) is not accessible to the public.

If you've ever tried it (might have as a kid, ahem) you can only crack open classic air operated sliding doors. It's enough to break interlock, but you can't get them open enough to fall out, maybe only a few inches. No more risk than an open hopper window. The reason for them being like this is to allow a trapped limb, jacket or piece of luggage to be pulled out.

Way back when I've been on a 150 in Bolton when it started moving with all doors open, but that was downhill (no power) and in the days when it was just power interlock, now there's brake interlock too.

The one I was on, the kids got the doors about two foot apart. Perhaps it was faulty. Aren't they simply held shut by air pressure?

They are held shut by air pressure but it's quite powerful. Aircraft doors are held closed by air pressure (unless misaligned due to missing bolts, yes, you, Boeing) and opening one is basically impossible.

Could have been faulty or maybe 150 doors differ from PEP doors. With the 507/508, the doors (with the original mechanisms, I can't remember if they do now) close to a "catch" about 3" apart, then slow for the final closure, presumably again to avoid trapping issues. You could (allegedly) only pull them as far as that "catch" before the pressure was too great to go any further. I did think 150s had the same feature (I've never, er, allegedly, tried) but maybe not.

As an adult I'm obviously not stupid enough to do something like this so I can only speak from the alleged (!) perspective of a 12 year old

 

[Halish Railway]

I remember someone from the school I used to go to had the bright idea to try and pull the doors of a Class 321 open when it was on the move which triggered an emergency stop.

 

[Bletchleyite]

I remember someone from the school I used to go to had the bright idea to try and pull the doors of a Class 321 open when it was on the move which triggered an emergency stop.

Yes, it'd certainly trigger the interlock (though way back when that was just door-power, not door-brake - I think the latter was only fitted to 507/508 in the 1990s refurb).

Do not try this at home (or on the railway) of course!

 

[12LDA28C]

Yes, it'd certainly trigger the interlock (though way back when that was just door-power, not door-brake - I think the latter was only fitted to 507/508 in the 1990s refurb).

Do not try this at home (or on the railway) of course!

Really? Since when has interlock not been related to the braking system? Failure to gain interlock would prevent a driver applying power from a stand but loss of interlock on the move above a certain speed (usually around 6mph) should certainly have always triggered an emergency brake application.

 

[Ben Anslow]

Yes, it'd certainly trigger the interlock (though way back when that was just door-power, not door-brake - I think the latter was only fitted to 507/508 in the 1990s refurb).

Do not try this at home (or on the railway) of course!

By all means try at home just not on the railway if you some how have a set of train doors

 

[Efini92]

Really? Since when has interlock not been related to the braking system? Failure to gain interlock would prevent a driver applying power from a stand but loss of interlock on the move above a certain speed (usually around 6mph) should certainly have always triggered an emergency brake application.

142’s didn’t have interlock originally.
155’s were only fitted with interlock about 10 years ago. If they master switch was in forward or reverse, the power couldn’t be applied but the train would roll upto whatever speed the gradients allowed.

 

[Towers]

I’m reliably informed that an IET will roll without interlock also!

It’s also the case on some stock that the door controls can be armed on the move and the passenger buttons illuminated, but unless a door is actually opened it won’t cause any sort of power/brake issue as interlock is not broken.

 

[12LDA28C]

I’m reliably informed that an IET will roll without interlock also!I'd l

It’s also the case on some stock that the door controls can be armed on the move and the passenger buttons illuminated, but unless a door is actually opened it won’t cause any sort of power/brake issue as interlock is not broken.

I'd be very interested to see your evidence for both those claims. Some trains can certainly roll with interlock lost / doors open but once they reach a certain (low) speed the brake should apply.

 

[Russel]

Pulling the doors apart on the newer DLR. Stock causes an emergency stop.

I've seen it done, they only opened by a few inches though.

 

[LowLevel]

I'd be very interested to see your evidence for both those claims. Some trains can certainly roll with interlock lost / doors open but once they reach a certain (low) speed the brake should apply.

If you use the local switch on a 158 you can certainly arm the local door controls on the move without impact on braking or accelerating unless someone actually presses the now illuminated open button. Not the most helpful of features.

 

[Towers]

If you use the local switch on a 158 you can certainly arm the local door controls on the move without impact on braking or accelerating unless someone actually presses the now illuminated open button. Not the most helpful of features.

Indeed, particularly given how easy it is to miss the local rocker switch having being left in the Open position!