I believe I read the other day BNSF taking delivery of new 6 axle gevo’s with only 4 traction motors. A1A I believe they called it. The middle axle being a dummy. What is the purpose of this? Must not be going to use them on coal,grain trains?
Having only four traction motors reduces maintanance costs. And it is still a 4400 HP, AC traction locomotive. One level ground, there is no difference between a 4 and 6 axle locomotive’s traction effort, except when accelerating.
Why not build an actual 4-axle locomotive without idler axles, you ask? Simple; it’s called price. Designing a new locomotive from the ground up is expensive, and both the railroad and locomotive builder would rather build an existing design with just minor modifications to make it a 4-axle locomotive. Proven technology and almost all shared componants.
Plus is this design flops think SD90MAC failure. All the BNSF has to do to make them GEVOAC44-6 the new designation is add 2 inverters and 2 traction motors and replace the Idler wheels and reprogram the computers. However scanner chatter on the transcon says the CREWS LOVE THEM.
You might want to refer to the other threads already here on this, such as:
“Re: BNSF’s New ES44C4 Class is A1A-A1A = 4 Motors on 6 Axles ! Forward to the Past ?”
at: http://cs.trains.com/trccs/forums/t/150880.aspx
In the first post are links to 2 other threads on this in the Trains.com “Locomotive Forum” as well.
Also, an Internet search will likely turn up a lot elsewhere . . . [:-^]
Hope this is helpful and informative.
- PDN.
If you type “ES44C-4” into the SEARCH COMMUNITY box to the right of this page you will find a couple of recent discussion threads on the TRAINS forums with lots of good info, pics, ect…