Slowly processing the remaining images, some roster shots from West Colton.
Snoot SD40-2
One for James, a big yellow EMD bruiser.
Ugly is as ugly does, but the pillbox windscreens give the face a no nonsense brutish look.
Another ball/squirrel moment, may have posted this before.
On the left a eastbound manifest heads around the outside of the balloon track, it'll turn right shortly and pass under the westbound manifest coming down off the Palmdale cutoff; from there it'll head out on the old SP sunset route down toward Mexico and along the southern edge of the US toward Tuscon and thence Texas.
The GEVO is coming down from Cajon on the Palmdale cutoff and will run past West Colton and onto Los Angeles.
The SD40-2's are running out of the classification yard and through the departure yard with a long manifest, before setting back into the classification yard to pick the tail end up. The departure yard is not long enough to hold a full train, so half will sit in the departure yard and the rear half in the classification yard. This does block the throat until the train departs, but that won't be long as the head end power will soon arrive and thence depart.
On the right the light engines have been serviced and run down the south side of the departure yard and are ready to back onto a previously assembled train.
West Colton seems to assemble two or three trains at once, each with it's own triple SD40-2 switcher set, light engines arrive and couple up and then all depart. After that it dries up for a few hours, no doubt the next trains are being made up in their respective halves before being joined and the process repeating it's self.
I did not seen any arrivals at this end, only departures west on the Sunset route and north on the Palmdale cutoff, nor did I see any trains made up with FREDs on the end ready for departing toward Los Angeles.
One thing I have noticed looking back through the photos, is how shabby the armour yellow paint becomes, turning first to a muddy mustard colour and then a pale washed out almost white affair. The official colour for the running gear and under frame is now light grey but many older units are brown from years of brake dust which has stained the whole underside of the engines.
A pair of nearly new BNSF ET44C4 engines, less than a year old I believe and still relatively clean.
These are new Tier 4 engines with enlarged split cooling radiators and raised engine cover. One way to improve emissions is to run the engine hotter, however that requires larger radiators. On the Class 66 the only way EMD could meet Tier two was to do just that, however the larger radiators and increased water capacity put them overweight for the UK axle limit. To claw some of this back they simply reduced the size of the fuel tank, thus the easiest way to determine a Tier 1 or Tier 2 class is the size of the fuel tank.
BNSF are also unique in that they run the C4 truck from GE, there are several ways to gain adhesion, one being more weight which CSX and UP both employ on their 'heavy' GE's.
Another is complicate electronics which induce wheel slip at a given rate, it has been found that adhesion rises when wheel slip begins and at 7% slip there is maximum adhesion available, at 8% it drops right off and you get wheel spin. You can tell when an engine is in super slip mode, the wheels hiss and scream with an ear piercing noise and emit smoke, it's different from sand dust and brake dust and easy to spot, but the noise is a certain give away. The electronics measure the actual speed with doppler radar and then increase axle speed to be 7% above actual speed.
One other way is to increase the weight on the wheels but still retain the overall weight. To do this the BNSF six axle engines do not have six traction motors, they only have four, thus are A1A-A1A. To increase traction, BNSF C4 engines employ a linkage on the outside of the truck which effectively lifts the middle axle and thus adds more weight to the remaining four powered axles. It must work, as to date as far as I know, all BNSF engines are now delivered with C4 trucks.
In this pace shot along Goffs road you can see the rams fully extended and lifting the middle axle to give maximum traction up the grade.
I've had a quick look through the Cajon photos and have not seen any with it employed, yet out here on a lesser grade it is clearly applied. In the West Colton roster shots 3752 does not have it deployed yet the trailing 3750 does, the train was beginning to power up and pull and I think the system is automatic and probably linked to super slip as well, thus each truck may be working independently and applying what ever adhesion level it thinks it needs.
MD