COP Stock

As a bit of an international comparison, here are two pictures of the cab from an old C4 stock car from Stockholm. They were built in the early to mid sixties, and are all now scrapped,by the way.






As you can see, we also used to have the old coffe-grinder handle, which had to be depressed at all times. If you let go of the handle, without having applied a full service brake, you went into emergency. And while the handles were supposed to have a sort of latching mechanism, requring less pressure to keep them in position once they had been depressed fully, that one did not exactly work as planned. These cabs were responsible for a lot if repetitive strain injuries and other workplace injuries, and the stock was relegated to running as middle cars in trains, with other stock leading, for quite some time before they were scrapped. The handles had three very distinct nothces for power, and a fourth coasting position.

The grey handle on the right in the picture is the (removable) brake handle, which you had to carry along with you. Cast iron, about 1kilo. Good for imposing a bit of order on unruly passengers In the picture, it is in the "cab activate" position. The full release/running position would be more or less parallell with the front windscreen.

These units, like the CO/CP stock Q8 describes, never had a speedo, so you had to rely on your judgement. Indeed, while trains were fitted with speedos from the early seventies onwards, they were always considered a non-safety critical device, and were formally not required to work. This changed with the changeover to ATP signalling on the green line, since the ATP display is incorporated in the speedo.

Now, we have always run on a cab signalling system, with the old-style display being mounted on the cab wall above the controller handle in the second picture. This display, as well as a very loud bell and buzzer, told you the maximum permitted speed for a particular section of track.

On newer stock, the train automatically applies a full service brake if you don't bring your speed within these limits within a few seconds. On the old stock, C2-C5, things were a bit different.

If you oversped into a section with a lower permitted speed, you got a warning bell. You then had about two-three seconds (depending on the condition of a time/magnet relay) to apply full service brake, zero the controller and kick an "cab signal acknowledge" pedal located underneath the driver's desk, in a maze of air piping and electrical cabling. And even then, if the (notoriously rubbishy) brakes didn't reduce the speed sufficiently within a few seconds, you would still end up with an emergency.

Of course, to make things even more fun, the tachogenerators providing the speed sensor input for the cab signalling system and their calibration varied from car to car. What one car decided was 45 km/h could be sensed as 52 km/h in another. And the time relays were also quite eccentric. And, since these cars were on their way out when I started driving them, the driver's brake valves weren't exactly well calibrated, either. It was very easy when applying full service brake in a hurry to "go over the notch" and end up with the handle in emergency and all the air dumped with a mighty bang that left your ears ringing.

In other words, driving C4:s gave you very strong incentives to learn exactly were all the code change points along the lines were, and certainly improved your kick with the right leg. And gave you a permanently bruised knee, too. But oh my, how zippy the C4s were when you got a good train and didn't have to stop for the forseeable future.


/Igelkotten, sometime speed demon.

Thank you Q8 and Igelkotten that was very interesting reading, I never thought COP's would be as bad as that, especially the part about an emergency brake application which only left the last car the station. Those C4's in Stockholm don't sound too clever either. The cab certainly looks grim. If you were born in a later age (1982 in my case) and never saw these trains in service you get an impression from books and talking to people that 'the old days were the best' and the trains matched. As Q8 says, this was not always the case and as AlanL says, I can imagine things are easier today.

Thanks for the excellent replies, they've been really helpful

I have no idea if there are any DVDs of the Stockholm tube available. I know that there are fragments about the tube interspersed with other things in some historical videos and so on, but as far as I know, there is no video or DVD solely about the Stockholm tube. Maybe Tom knows about one?

For a lot of pictures from Stockholm, including driver's eye views and photos from the depots, take a look at Tom's Fotopic site:

www.tunnelbana.fotopic.com


/Igelkotten