In recent past articles in Trains, there has been mention of distributive power being a relatively new concept of moving long trains especially with the new technology of controlling mid and rear units. I do remember back in the early and mid ’60 when I would watch Southern Pacific trains going through Reno Nevada crossing Virginia Street on their way to or from Donner Pass seeing three or four F units in front, three in the mid section and two or three in the rear sectoin. Would this be considered using distributive power and what technology was used to control the power of these mid and rear units.
Back then those helpers were manned with 2 men in them. DPU really came of age with Locotrol however the equipment at first required was so large for the reciever a boxcar or converted booster B unit was required to hold it being Vac tube tech. Now the tech is so intergrated that it basically the size of a briefcase in the engines.
Locotrol is DPU for the most part. GE bought the product and almost all class 1 DPU in the US is Locotrol. No longer requires an extra car or long snoots to hold it.
Distributed power technology was in limited use as far back as the 1960’s. The earliest model of the locotrol system was tested by the Southern Railway in 1963 and they did adopt it after that. IIRC, Norfolk and Western may have used a version as well. L&N experimented with unmanned mid-train helper locomotives that were controlled by strain sensors on the units front coupler, Ie not radio controlled but when the instrument on the coupler detected pulling forces it automatically throttled up the engine.
I don’t believe any of the Western railroads used unmanned/remote controlled power back then…
Northern Pacific was also a fairly early tester, using U25Cs equipped as Masters and IIRC a pair of steam locomotive tenders briefly, followed by a pair of F-unit boosters.
UP and MILW also dabbled with Locotrol. UP had a pair of SD45’s equipped and MILW had some SD40-2’s in a separate number series equipped. CP was a fairly large user and was noted for its Robot cars (receivers) rebuilt from retired FB-1’s.
Here is a site with CPR Robot Cars.
http://www.mountainrailway.com/CP%201000%20Page%203.htm
CP started experimenting w robots 1966 1967, at first using a Silk Box Car ( Silkbot ) to house the remote equipment, powered by jumper to locomotive coupled and for operating air.
This was before the CP Rail Multi Mark scheme was implemented.
We were at tests in Montreal in 1967 where the Master Unit radio-controlled the ‘Slave Set’ on an adjacent parallel track for Demo purposes. The three 3 SD40s used had wheels limed in white.
CP 5557 and Robot 1 Vancouver, August 1968.
http://www.fototime.com/photos/st/9D10FFF02B93434DA1F4B4A3AA401FB9/CP-04-812.jpg
Model of first Robot Car, still with it’s Psgr. number.
http://www.readytrain.com/catalog/cpr_robot/cata/index_files/4472.jpg
http://www.readytrain.com/catalog/cpr_thr-baggage/cata/index_files/4476.jpg
http://www.readytrain.com/catalog/cpr_robot/cata/index_files/1002side.jpg
Anyway.
The Silkbot cars were found to be too light for their uses and one ‘popped’ out of it’s train under severe in-train forces.
Various B Units were then used, the CLC OP ones called ‘Fairbots’, a FB from MLW and another from a H-16-44.
The Box Car Robots, built new, were called ‘Boxbots’.
When in use, the line side forces used to wager 25 cents a man to guess th
McMillan says SFe’s first radio control car (rebuilt F7B) came out in August 1967-- doesn’t say when it began York Canyon service. That was the first radio control experiment west of Chicago?
A little more to it than that, in line with the general theme of the post. The B unit in question is the one rebuilt (at some expense!) with an Alco 251 and appropriate main generator, and the breaker operator (coal breaker, not ‘breaker’s yard’ btw) put the rubber-tired chassis on it for ‘portable power’. Sadly this conversion is one of the stated reasons why somebody didn’t buy the ‘rest’ of the unit (it was reportedly for sale for $3000 to anyone who would move it, at one point) and it succumbed to high scrap prices when the rest of the breaker was cleaned up.
I’m surprised that nobody has mentioned that Distributed Power is an inbuilt feature of ECP braking.
The MU signals are sent down the 250v DC bus line that also provides power to the ECP system and digital control signals for the brake valves.
In Queensland on the lines leading to Abbott Point, Aurizon coal trains run with three locomotives,one on each end and one in the middle under Locotrol radio control, while Pacific National trains run with two locomotives leading and one on the rear under ECP braking and control. The ECP braking means there is no need to put a locomotive mid train for braking advantages.
In South Australia The iron ore trains from Wirrida to Whyalla operated with two locomotives leading and one trailing under ECP control. These trains stopped with the downturn in mid 2014, sadly. An interesting feature was that the trailing locomotive was shut down on the empty runs but could be started remotely to return on the loaded train. This was important because the run exceeded the fuel capacity of the locomotives (10 000 litres) and the leading pair had a flat car with two 25 000 litre tanks attached (as well as a sleeping and lounge car for the relief crew). So the lead locomotives could run continuously but the trail locomotive could only operate in the loaded direction. The train reversed in Port Augusta, but no switching of locomotives was required.
On the BHP Billiton line, trains are made up of two SD70ACe units each hauling 110 ore cars of 140 tonnes gross (154 US tons) all with ECP brakes. These are coupled in sets of up to three sets of two units and 110 cars to reduce track occupation.
In Australia ECP is very common, although the distributed power function isn’t used much since distributed power isn’t needed for improved braking, only to reduce drawbar forces.
Peter