This section is to help people unfamiliar with the various kinds of railroad cars and railroad operations understand what they are seeing on the Flagstaff camera. This is a work in progress. Currently there are 13 other pages:
Anatomy of BNSF Train Symbols
Bare Table Trains
Manifest Trains Westbound
Manifest Trains Eastbound
Q Trains Westbound
Q Trains Eastbound
Marine Stack Train Overview
Marine Stack Trains Westbound
Marine Stack Trains Eastbound
Z Trains Westbound
Z Trains Eastbound
Transcon Traffic Density
Autoracks are used to transport automobiles, pickup trucks and other delivery vehicles. In the 1960s these cars were open and you could see the vehicles inside. The sides and roof were added to keep rock throwing kids from damaging the cars while in transit. End doors were added to keep people from hitching a ride. If you are on the shadow side of the tracks and the autorack is loaded, you might be able to see the outline of the vehicles, otherwise it is hard to tell a loaded car from an empty.
Boxcars carry general cargo that does not require refrigeration. Most of the things loaded into a boxcar are on pallets for ease in handling. Forklifts are used to load and unload most of the cargo handled in boxcars. In the picture the boxcar on the left has a regular sliding door. The boxcar on the right has a plug door. The plug door has a tighter fit against the door opening to keep dust and rain out. Plug door boxcars have small vents to relieve pressure changes due to altitude as the cars move over mountains. In the 1940s and 50s, the boxcar was the most common type of freight car. However, in the 1950s grain began moving in covered hoppers. In the 1960s automobiles began moving in auto carriers, now called autoracks. From the 1950s through the 70s, much of the freight moved by boxcars went to the trucking industry. In the 1990s, shipping containers revolutionized general cargo transportation. More on containers later. Federal regulations limit boxcars to 50 years of service. So boxcars are being scraped faster than they are being replaced. The total number of boxcars has dropped drastically from around 750,000 in 1950 to about 120,000 today.
Domestic containers are generally 53ft long, where marine containers are 45ft or less. The domestic containers you will see on BNSF trains moving by the Flagstaff camera primarily are from three big trucking companies. In 2015, JB Hunt had 73,300 containers, Schneider had 17,200 containers, and Swift had 9,150 containers. Smaller fleets belong to UPS 5,000, CSX 4,000, FedEx 1,850, APL Logistics 1,000, CH Robinson 1,000, COFC Logistics 475, and Matson Logistics 300. Don't confuse the Matson 53ft domestic containers with Matson 40ft marine containers or APL 53ft containers with APL 40ft marine containers. You will see domestic containers on both Q and Z trains. Containers from the Hub Group, Pacer, EMP, UMax, CR England, and Tiger Cool generally are on Union Pacific trains.
Centerbeam flat cars are like regular flat cars, but have a frame on the centerline. Centerbeam flats generally handle construction materials like lumber, plywood, and sheet rock. Often the cargo is covered in paper to protect the cargo from rain and snow. The two cars to the right of the centerbeam flat car are bulkhead flat cars. The bulkheads at either end of the car keep cargo such as lumber or pipe from moving against an adjoining car due to rough handling by the engineer of the train or coupling to another car at too high a speed. These two cars are hauling structural steel.
Covered coil cars handle coiled steel and aluminum. When manufactured the steel or aluminum is flattened and then coiled up like a roll of toilet paper. To protect the steel from rusting in transit, the coil cars are equipped with removable covers. You can see the loops on the top of the covers used for lifting.
Covered hoppers handle bulk materials that are a powder like cement, granules like sand or grain, or pellets like chicken feed. The short cars usually with two bays haul heavy bulk materials like cement. The standard 47ft long cars with three bays are the most common and haul grain, corn, and feed. The longer cars have four or five bays and haul plastic pellets and distillers grain (DDG), which is a by product of ethanol production. Notice in the picture the covered hopper on the right has four bays. Inside the car are four different compartments, so the car could possibly be hauling four different products. When I worked at a chicken feed distributor, we got very few orders for broiler feed. So we rarely got an entire car with broiler feed. Instead one of the three compartments would have broiler feed and the other two compartments would have a different type of chicken feed. Also notice in the picture, the car to the left of the covered hopper is a flat car with wheel sets. The train is the HKCKBAR and this is one of the distinguishing features of that train.
Mechanical reefers are basically an insulated boxcar with a refrigeration unit attached. You can see the diesel refrigeration unit on the end of the mechanical reefer next to the locomotive on the left in the picture. A similar looking car is cryotrans which uses liquid carbon dioxide as the coolant. When originally built the cryotrans cars didn't have diesel refrigeration units. Some of the cryotrans cars had diesel refrigeration units added.
Piggyback is the slang term used for trailer on flat car or TOFC. This is a primary indicator that the train might be a Z train. There are three designators for intermodal trains: S (stack) is used on all intermodal trains carrying exclusively marine containers. Z is used on the highest priority intermodal trains moving UPS, FedEx, and truck trailers with time sensitive cargo such as perishables. Customers pay a premium price to get their cargo on a Z train. The average Z train covers about 800 miles in a day. The next designator is Q (quality) for standard or guaranteed service. Q trains cover about 600 miles a day. They can be exclusively domestic containers, or be a mix of domestic and marine containers. Occasionally, but not often, a Q train will also have a few truck trailers in the mix. More details on this later.
Midwest farmers have been exporting corn, wheat, and soybeans to Asia for years. About 20 years ago someone got the bright idea to use the empty marine containers for shipping these product west. There were multiple advantages in doing this. It reduced the expense to the steamship company by getting a revenue backhaul. It benefitted small businesses in Asia that didn't need an entire boat load of grain. It improved America's trade balance. It enabled some steamship lines to retire older less efficient grain ships.
For the marine container (S) trains moving west through Flagstaff you will often see some that up to 95% of some trains are single stacked. This is a good indicator that the train originated at Logistics Park Chicago (LPC) in Joliet, IL or Logistics Park Kansas (LPK) in Gardener, KS. In 2017, the U.S. exported around 94 million tons ($14 billion) of soybeans to China. The average 40ft marine container will have about 25 tons (20ft container 21 tons) of wheat, corn or soybeans. The average 40ft marine container will have about 10 tons of product when loaded with furniture, tennis shoes, or TV sets due to all the packaging. That is why you see mostly double stacked containers moving east and many single stacked containers on some trains moving west.
Tank cars carry all things liquid, from corn syrup to fuel oil. Due to the high cost of cleaning, tank cars generally spend half of their life returning empty. You will see this on the unit ethanol trains that go by the Flagstaff camera. Loads go west and are pulled and pushed by five to seven locomotives. An ethanol train of 96 tank cars plus the two idler cars (used to separate the locomotives from the tank cars) will weigh around 12,500 tons. When returning empty the train will weigh about 3,300 tons and generally only have two units.