Next Series Cars

"Anyway, just throwing some thoughts out. Out of curiosity, considering the possibility that Alstom will get the contract for the 7000s, would anyone happen to know how the 6000s have been performing so far? Are they still having troubles slowing their acceptance into the system or other notable teething problems?"


6000 already have 200 Field service improvements needed. They are 1 year behind sechedule and three times the fleet of them have been down. However they are much better than the 5000s which are still not correct.

At least there is some good news hearing they are doing better than the 5000 series cars.

Who knows...maybe we will still see BBD, Kawasaki or Siemens bid on the next series as well. Just hope its not the manufacturer Rotem. Philly gets to be the guinea pigs using the Korean manufacturer for the first time ever in the US with the new Silverliner V.

Some scoupe about the 7K cars.
Plans are done. Now they will go about getting funding for them.


Some design features...... The bodies will now be stainless steel instead of aluminum. Had some problems with corrision when they were shipped from Barcelona Spain. No longer will be built there. Depending on the thickness they will now be heavier. Front platform doors will be back about 3 feet on both the a and b car. Aside from that will be very similiar to the 6K.

"Mike Morris"
Some scoupe about the 7K cars.
Plans are done. Now they will go about getting funding for them.

Glad to here this.

Some design features...... The bodies will now be stainless steel instead of aluminum. Had some problems with corrision when they were shipped from Barcelona Spain. No longer will be built there.

Back when WMATA was in its planning stage a couple of aircraft manufactures began diversifying their manufacturing capabilities into the transit equipment industry. Rohr was one of those companies. Rohr (manufacturer of the 1k cars) worked closely with WMATA in drawing up the specification for the aluminum body cars they sold to WMATA. The theory behind the design was to make the car body structure an interracial part of carrying live load in the car instead of building a box on a flatcar. The thinking was the weight of the center cell beam and the frame thereon used in conventional passenger rail car design could be reduced by distributing that weight throughout skin of the car body, as an example an aircraft fuselage. As I recall all of the cars that came after the 1k car became progressively heavier as more of weight of live load was transferred from the body shell skins to the center cell beam and frame.

Depending on the thickness they will now be heavier.

Fact is stainless steel is pound for pound structurally stronger then aluminum in vast majority of non aviation applications.

If the engineers that drew up the structurally designed specifications for these new cars ran the numbers correctly and did their homework right, the basic car shells will likely be lighter then the total fleet average and be more crash worthy to boot.

Front platform doors will be back about 3 feet on both the a and b car.

I will assume the passenger door relocation was done to improve the crash worthiness of the cab ends as required by the NTSB.

A set of the 1k cars spent some time at the American Association of Railroads Transportation Technology Center in Pueblo, Colorado. I wonder if as set of these cars might spend some time out there as well.

Aside from that will be very similiar to the 6K.

Brushed stainless steel can be made to look almost like brushed aluminum. Most will not know the difference. Generally speaking aluminum is brighter then stainless steel.

Interesting...stainless will definitely be an improvement over brushed aluminum. Any word on other bidders likely for this series other than CAF, Breda and Alstom?

I know all the current series of cars are have aluminum car bodys, but they all look like they were not constructed of the same material. I've noticed that the CAFs and the new Alstoms have shiny brushed aluminum finishes, while the Rohrs and Bredas (including the rehabs) have a whitish, dull finish. I definitely prefer the look of the CAFs and Altoms, but why do the other cars look different?

Also, I think the switch to stainless steel is a step backwards for Metro. I dont understand how cars constructed with stainless steel can be lighter than aluminum cars.

"realtype"
I know all the current series of cars are have aluminum car bodys, but they all look like they were not constructed of the same material. I've noticed that the CAFs and the new Alstoms have shiny brushed aluminum finishes, while the Rohrs and Bredas (including the rehabs) have a whitish, dull finish. I definitely prefer the look of the CAFs and Altoms, but why do the other cars look different?

The 1, 2, 3 and 4k car range in age from 25 to 35 years, the 5 and 6k cars are less then 10 years old. Believe it or not aluminum oxidizes (rusts) much like steel does. The 'whitish dull finish' as you call it is what happens to aluminum when exposed to the elements after a long period of time. I knew this was going to happen because my one of the products of my father business when I was as a kid back in the early 1960s was the manufacturing of aluminum boat hardware. The surface of that hardware oxidizes after several years of exposure to the environment.

Also, I think the switch to stainless steel is a step backwards for Metro. I dont understand how cars constructed with stainless steel can be lighter than aluminum cars.

You obviously don't know how thick the aluminum skin is on the metrorail cars or the difference between the strength properties of sheet stainless steel compared to extruded aluminum. The larger mass (more weight) need to meet the structural requirement with aluminum is far greater then the mass need (less weigh) to meet the same requirement using steel. The typical thickness of the stainless steel used on the skins of passenger rail road cars is roughly the same thickness used in automobile body panels 1/32" (0.79375mm), the typical thickness of the aluminum extrusion on metrorail cars is around 1/8" (3.175mm). Mind you the these cars will likely have internal structural components made of stainless steel that will be thicker then the exterior skin, but no where near an 1/8" (3.175mm). The aluminum extrusion on the metrorail cars have ribs running longitudinal on the back side of the exterior skin that are similar in thickness to the exterior skin.

Metro would not be the only agency to switch from brushed aluminum to stainless. MARTA down in Atlanta originally built its cars with aluminum back around 1979 for the first 2 series by Franco-Belge (Alstom) but then by 1987 switched to stainless when Hitachi did the 2nd generation and then Breda continued that in 2000 with those cars.

There really is no huge difference in the look at all, except they dont end up getting that coating of rust on the bodies. It could actually save on car washing expenses and time to chemically treat the bodies to remove rust. Plus if they can hold up better over the long haul, its a good thing.