"Generations" of diesel locomotives?

[emdSW1200]

Howdy, I've got three questions pertaining to the history of diesels in the United States...

What was the first "second generation" diesel locomotive?
What exactly is the distinction between the first and second generations?
Have we entered a third generation, and if so, when did that occur? (Alright, that's two questions in one)

Thanks.

 

[AlcoFanRS27]

I don't know what model exactly you could say "started the 2nd generation" but I do believe that the definition of a "2nd Generation diesel locomotive" are diesel locomotives that replaced the diesel locomotives that replaced steam (1st generation).

To possibly answer the last question...Something tells me we are in the "4th generation". I want to say it started in 2005 when the Tier 2 emission requirements went into effect on new diesel locomotives (GE's ES44AC's or ES44DC's and EMD's SD70ACe or SD70M-2).

I maybe totally off base, if I am someone please correct me.

 

[April]

As far as EMD's I heard it was when they went from 567 to 645-based engines.

April

 

[Zoohogger]

second Generation

I always thought of the GP30 as the beginning of the second generation, even though it has a 567. I do like the idea of the 567 to 645 transistion being the dividing line. The GP 30 seemed "different" at the time, almost like something new. GP20 never seemed new enough to be a second generation.
I'll have to check out a diesel spotters guide and see what it says. SD45's for sure would be second generation.

As far as GE goes, U25B, maybe?


I'm sure there is a someone who knows the differences in the electrical systems. Something akin to when computer chips started being involved in the controling of the electrical, which I suppose would have started the 3rd generation.

All I know is that I would rather listen to a normally aspirated 567.

 

[bcp]

From:
http://history.gmheritagecenter.com/wiki/index.php/The_Electro-Motive_Story

In 1965, the second-generation 40 Series locomotive was introduced.
...
The next generation 50 Series locomotive was introduced in 1979.
...

 

[Bruce Butler]

From "The Electro-Motive Story" - last paragraph (bolding added by me):

In 1962, EMD had produced its 25,000th locomotive, making it the worlds leading manufacturer of Diesel locomotives. In 1965, the second-generation 40 Series locomotive was introduced. The new 645 Series Diesel engines powered it and in 1972 EMD celebrated its 50th anniversary, commemorating Electro-Motive Engineering’s 1922 date of incorporation. The next generation 50 Series locomotive was introduced in 1979. By 1983 EMD had built 50,000 locomotives and 1984 saw the introduction of the 60 Series locomotives with the 710 Series engine. It had the newly developed wheel adhesion control system. Burlington Northern placed the largest ever single order with EMD in 1993 when it ordered 350 SD70MAC units equipped with the new AC traction technology. 1997 marked EMD’s 75 years of excellence and 1998 saw the addition of the 265H engine to join the 710
Series already being built.
===============================================
From my limited experience as an Engineer, I would suggest this:
1st generation: E and F units and geeps and SD's thru GP20
1.5 generation: EMD GP30 & GP35 and all GE "U" series.
2nd generation: all with 645 engine, mostly GP40, SD40, 1966-1972
2.5 generation: the EMD -2 line and early GE "C" series
3rd generation: The EMD 60 series, beginning with the 710 engine, and GE's dash 7 series.
3.5 generation: Early EMD 70 series and GE's dash 8 series
4th generation: EMD SD70ACE, SD70M-2, GE dash 9 and EVO models
-------------------------------------------------------------------------------------
Just my thoughts. Having more operating experience with 3 SD45's and 1 SD40-2, I was surprised at the differences between the earlier electrical systems and the -2 electricals.

One could argue that the GE "U" series were true 2nd generation, but they sure didn't survive long when compared with EMD's 40 series. I will let others speculate on where the SD80 and SD90MAC43 and SD90MAC60 along with the 6000hp GE's belong.

 

[AlcoFanRS27]

From "The Electro-Motive Story" - last paragraph (bolding added by me):

In 1962, EMD had produced its 25,000th locomotive, making it the worlds leading manufacturer of Diesel locomotives. In 1965, the second-generation 40 Series locomotive was introduced. The new 645 Series Diesel engines powered it and in 1972 EMD celebrated its 50th anniversary, commemorating Electro-Motive Engineering’s 1922 date of incorporation. The next generation 50 Series locomotive was introduced in 1979. By 1983 EMD had built 50,000 locomotives and 1984 saw the introduction of the 60 Series locomotives with the 710 Series engine. It had the newly developed wheel adhesion control system. Burlington Northern placed the largest ever single order with EMD in 1993 when it ordered 350 SD70MAC units equipped with the new AC traction technology. 1997 marked EMD’s 75 years of excellence and 1998 saw the addition of the 265H engine to join the 710
Series already being built.
===============================================
From my limited experience as an Engineer, I would suggest this:
1st generation: E and F units and geeps and SD's thru GP20
1.5 generation: EMD GP30 & GP35 and all GE "U" series.
2nd generation: all with 645 engine, mostly GP40, SD40, 1966-1972
2.5 generation: the EMD -2 line and early GE "C" series
3rd generation: The EMD 60 series, beginning with the 710 engine, and GE's dash 7 series.
3.5 generation: Early EMD 70 series and GE's dash 8 series
4th generation: EMD SD70ACE, SD70M-2, GE dash 9 and EVO models
-------------------------------------------------------------------------------------
Just my thoughts. Having more operating experience with 3 SD45's and 1 SD40-2, I was surprised at the differences between the earlier electrical systems and the -2 electricals.

One could argue that the GE "U" series were true 2nd generation, but they sure didn't survive long when compared with EMD's 40 series. I will let others speculate on where the SD80 and SD90MAC43 and SD90MAC60 along with the 6000hp GE's belong.

Makes sense...where would you suppose ALCo products fit in? I would say 1st Generation and maybe 1.5 or early 2nd generation with the Century Series?

 

[Tower 55]

According to EMD and many of its historians, EMD's second generation began with their use of turbochargers. The first second generation EMD locomotive is the SD24. See Brian Solomon's EMD Locomotives for a much more in depth reasoning.

 

[trainboyh16-44]

I'd say that the GP30 has to be second generation...I mean, so many of them rolled out with trucks re-used from the first gen.

 

[Tower 55]

It is, but then again its also a 16-567 that has a turbocharger.

There is an argument as to what differentiates Generation 2 from Generation 3. Is it the 645 prime mover? Is it Dash-2 technology? I lean towards the latter.

 

[Jay Potter]

During the early 1960s, around the time that railroads began acquiring substantial numbers of GP30s and U25Bs, the terms "first generation" and "second generation" began being used in reference to the diesels that had replaced steam and to the diesels that had begun, at the time, to replace the steam replacements. It was relatively easy, for any given railroad, to place a given diesel in one of those two categories; and so the categories were -- and still are -- widely used. As diesel-locomotive technology advanced from there (i.e. microprocessor control systems, higher horsepower, AC-traction, environmental compliance, complete rebuildings, etc.), commentators began referring to "third generation" and even "fourth generation" diesels. My impression is that neither of those categories ever became generally accepted because there were a variety of opinions as to what characteristics should be used to place locomotives within each category. So it appears to me that the meaning of the terms "third generation" and "fourth generation" varies, depending on who happens to be using the terms. I presume that people will continue to suggest that certain locomotive should be included in each of those categories; however it would surprise me if there is ever a general agreement about any diesel "generation" beyond the first and second.

 

[BuddyBurton]

Two Generations of locomotives

ES44C4 BNSF 6688(left) and E5 Burlington 9911A(right) at Train Festival 2011.