Drawbridge incident

October 2018

Yesterday I sent round a reasonably polite request for information to Dutch contacts about the railway drawbridge, in the hope to finally find out where this three-track railway drawbridge was located. This was after two weeks of trawling through internet files and having seen virtually all of the rail- and road drawbridges in The Netherlands. Some truly inspiring ones did pop up, I confess, especially with regards to the variations within the actuation gear of the bridge movement. But I could not locate this particular bridge which, as we know, I will try and recreate in 1:160 on my N-scale model railway. Yesterday evening I finally found where the bridge once stood. Once, this is The Netherlands, remember, unlike e.g. Britain a nation of fanatical cleaner-uppers of stuff no longer in use and to the average eye unlikely to bring in more tourists. These two drawbridges could be found at Wormerveer. They have fairly recently been scrapped and replaced with higher positioned modern bridges to the best of my present knowledge. The three-track one was located close to the West of Wormerveer station and the two-track one of the same Netherlands Railways standard type near the Papenpad, which loosely translates as the Papists Alleyway.

The really interesting one is this one though. I couldn’t get it any bigger so enlarge it on your screen if necessary.
The location was in the Zaanlijn from Amsterdam via Zaandam to Uitgeest and Alkmaar, in fact the first route Stanley Hall and I travelled in the year 2000 on our quest to find out about Automatic Train Protection in The Netherlands. And also part of the last trip (2005) ever that I made at the controls of a train, from Nijmegen via Arnhem, Utrecht, Amsterdam, Zaandam and Alkmaar to Den Helder and back. Furthermore, going through my slide and negative files I actually found the contact prints that proved I had already noticed this bridge before and took colour pics, sometime in the early 1980’s. Unfortunately, in the course of several moves within NL and the UK I must have lost those negatives. Never mind, a tot of single malt calmed the resulting frayed nerves and there still is enough material to work with. These pics come from the municipal archives of Zaandam, the Gemeente Archief Zaanstad (GAZ).
To start with we can see that the Zaan line had been electrified. Notice the stanchion of the catenary in the right margin and the “fingers” of the wire contacts for those across the bridge sticking out from the left margin above the coach. The electrification went into service in 1931, when main line traffic became operated with sets of 1924 EMU stock. The vehicle involved, however, is an 1890’s vintage steam loco-hauled 3rd-class typical HSM Holland Railway (no clerestories) wooden vehicle on Fox type “English” bogies (trucks). There is, incidentally, precisely such a vehicle in the Railway Museum in Utrecht, they were in service till about 1950. This picture therefore in all likelihood concerns steam-hauled stock of a train for the line to Purmerend, Hoorn, Enkhuizen and Medemblik; the section from Hoorn to Medemblik nowadays operating as a museum steam line. The picture of the green drawbridge at Medemblik I sent previously, with the diesel hauled teak-built tram crossing it, comes from that particular line. It is clear that there is no non-wired gap in the catenary across this Papenpad drawbridge, similar to the three-track version of this bridge near the station on pics two and three. On this picture the 1.5 kV DC “ladders” along which the pantographs slide in happier circumstances can be made out between the bridge deck and the arms of the balance lift equipment. What can be seen clearly is the “Panama-Wheel” actuating gear in its opened position, very typical equipment for these Netherlands Railways standard bridges according to the railway engineering manual from the 1930’s. I haven’t found any other example of this type of bridge away from West Friesland, the area between the Zuyder Zee and the North Sea to the North of Amsterdam, which was HSM Holland Railway territory. Compare that with the same equipment on the attached other two pictures of this type of bridge in the closed position.
The reason these Panama Wheels were used is that they allowed the use of cheap and simple 50 Hz three-phase AC electric motors. Which, however, had no speed-controls as DC motors allowed, for which reason they could not be varied in speed in those days. That would require expensive stuff such as Ward-Leonard equipment, but to spend on installation and maintenance of that crane equipment was nonsense when thinking of how often this bridge would be operated in comparison to, say, a harbour crane. Ans so, to enable a well-controlled operation of the bridge, the Panama-wheel. If you follow the movement of this Panama Wheel then you can imagine that right at the start (0 degrees) and at the end (180 degrees) of the movement it performs slowly, its full speed with the bridge deck only occurs at half-way point (90 degrees) through the half-circle. At the end of its 180 degree turn, because it slowed the movement right down again, it is easy to stop the movement with buffers and an automatic switch. Additionally, the bridge deck can’t go anywhere, an arrangement that can be noticed in the way that in the open position the whole excellently designed assembly fits flat together. For road bridges of this type the stretched Panama Wheel “pre-loads” the bridge deck on to its seats when down, and thus will prevent it from dancing on its stops in case of heavy traffic passing over the gap between road and bridge deck. This was different on the railways: they demanded that the closed bridge deck behaved as a fixed bridge and additionally they took measures to ensure that no vibrations could pass from the bridge deck into the gear above. In the case of these particular types bridges they had steel cables between the balance beams and the bridge deck that would go slack in the down position; these can be vaguely seen in this photo. The big old four-track bridge in Amsterdam that started this all had a slotted connection which, when unloading from hanging tension after seating the bridge deck on its stops, physically disconnected the hangers from the balance beams to the bridge deck. Wonderful stuff, really, instantly understandable for anyone with a little bit of a technical eye.

Now, the interesting bit: what happened here? This bridge was clearly opened for the well-loaded barge, a type of a historical and present day still much used vessel known as a dekschuit in Dutch. You can tow or push them with a tug and, as probably was the case here, have the crew use poles to punt them along in narrow waters: they didn’t often come in motorized versions, certainly not in the scores of fairly shallow rural waterways found in the West of The Netherlands. Between the prescribed regular dredges to ensure they are usable as drains (see the lock door in the foreground) these may be abundantly filled with weed and snag your propeller. Such vessels have no holds normally, all cargo is stowed on deck and they are used for a wide variety of jobs. The picture I sent of the former bow-string bridge and its renewed drawbridge across the Spaarne at Haarlem show a few dekschuiten used by the contractor working on the piers for the new bridge. By the looks of it the skipper on this one, standing aft, was just about midway sailing the gap under the railway when this attack on his tranquil existence occurred. Was he smoking a pipe, as tales intimate was what skippers did? If so, what happened to it?Looking at the underside of the bridge deck we notice that the reinforced bit for the tracks is actually behind the coach, so the coach could not have been rolling on a track that would cross the bridge. Also, the absence of a steam locomotive, poised to take swimming lessons instead of this coach, indicates the fact that this coach was propelled, pushed. All together this points at the fact that the coach was pushed into a siding and rolled fairly violently through the bufferstops on the left side of this picture. Its speed, and probably the mass of the vehicles coupled to it, are indicated by the fact that it jumped the gap and hit the bridge deck at the other side, then, having lost its bogie, started to come down towards the water but -luckily- found the dekschuit and settled on its cargo. This, therefore, undoubtedly is the result of a rather iffy shunting/switching move. The question still to be asked being whether the locomotive was attached and the driver made a cock-up with the brakes. In that case probably using the locomotive brake rather than the train brake; we all did that when we didn’t want to have to pump the brake pipe back to pressure every time a vehicle was removed or added. Or, worse, the loco crew and shunter “kicked” the set (afstoten, fly-shunted it) and the shunter and his steel brake scotch (remschoen) on the track, assuming that was the idea to stop the movement of the set in that case, was insufficient to get it to stop in time. It happened before and probably still happens these days if there is no inspector near. Would really love to read the crew reports on this one but anyway, it wasn’t a glorious moment with regards to railway efficiency. Sincerely hope the skipper was OK, probably besides a smelly trouserful.
Removing the 35 tonne coach probably was a mite more difficult than at first sight imagined, as floating derricks or cranes could in all likelihood not be brought in proper position near the stricken vehicle resting comfortably on the bales. The only viable place to put some effort in lifting probably is the gappy bridge track nearest the coach, where a railway crane could be positioned at half way next to the coach. You can only hope that vehicle gets scotched to prevent it rolling according to all applicable regulations.
The things that may upset your working days on the tracks; eh? This one, stemming from a silly small shunting/switching incident, is fascinating. Wonder what all the accompanying sounds were like. Especially hopping off the track, hitting that bridge and the cursing and swearing of the skipper.

Utrechts Volksblad of Monday Jan 16th, 1939, dating the accident to the previous Saturday:
At about 12 o’clock, whilst shunting an empty passenger train, one of the carriages ended up in the passage of the bridge over the Papenpadsloot, which bridge was opened to allow a wood barge to pass through. The man on the barge was still able to put himself in time in safety, so that no personal accidents occurred. The fall of the passenger carriage on the barge, which has now largely sunk, gave a blow, which was audible far into the circumference. The damage to the passenger carriage and probably also to the bridge, is considerable. The train traffic in the direction of Alkmaar and Enkhuizen is experiencing this accident, which is a few hundred meters north of the station Zaandam, as a major nuisance. The railways have rushed in buses, which will transfer the travellers from the direction of Alkmaar from the station Koog-zaanstad to the station Zaandam, where they can continue their journey to the capital by Train. Only on the interlocking between the stations Zaandam and Koog-zaanstad there can be no trains, but as a result the train traffic on the sidelines to Enkhuizen is Impossible. The railways consider that the passengers, who have to make use of this line, have to transport buses from Purmerend to Zaandam and Vice Versa. Work cars from Amsterdam will come to start the clearance Work. The bridge-keeper, who has opened the railway bridge for the Wood-barge navigation, was not blamed for it. He had the message of the signalman that this could be done safely. Contrary to the rules, the rear car of the long passenger train, which was to be shunted, does not seem to have had a man who could warn the Machinist.

That rider at the far end of the train would have had the air brake to stop the movement by either pulling an emergency brake handle in his carriage or, as is done on many networks, attach a portable brake valve to the brake pipe connection to stop the move from his end. Furthermore, what surprises me is the fact that an opened drawbridge of this type and size is not exactly invisible as such, especially in flat countryside as the Zaan area is. So non-adherence to given rules by staff as well as an apparent lack of bother to observe signals and the state of the road ahead of their train (however difficult that probably was) once more strongly appear to have been the root-cause of an incident. I wonder, incidentally, how come the requisite signals such as the platform starting signal apparently did not obviously enough show stop or cease all shunt-movement aspects to protect the opened bridge: the driver or his fireman should most certainly have observed those before starting the movement.