Would you see an E7A by itself or would you always see it with a E7B?
I’m assuming the same would go for a E6A/B.
Depends on the length of the train. Both the New York & Long Branch and the Rock Island ran single E7s on commuter trains.
It was quite common to see E units (A’s) running by themselves on fairly short trains. Single A units were very common on the Boston & Maine and Maine Central. When the Wabash “Bluebird” was streamlined, the consist was 6 or 7 cars and a single E-7. Great Northern’s “Red River” was a 5 car streamliner using a single E-7 as was the “International” http://www.railwayclassics.com/gn07.htm.
IOW, keep the consist down to 5 or 6 cars and a single E unit is perfectly appropriate.
Andre
Many passenger trains only required a single EMD E7 or for that matter any of the E units. Trains that operated with a single E7 that come immediatly to mind were the GN Internationals, Badger and Gopher. The C&EI Whipporwill and Meadowlark A good rule of thumb seems to have been if they were seven car’s or less a single E was sufficient for power except in mountainous territory. Over six or seven cars many railroads operated an A-B set or A-A such as the GN for the 11947 Empire Builder. SP chose A-B-B sets of E7s to power the Shasta Daylights initially and also purchased the same power for the Golden State between Los Angeles and Tucumcari. The E7 was the most popular of all the E units and was owned by more roads than any other E-unit.
not sure about the E6’s or E7’s but the BN ran E8a’s on Chicago area push pull commuter services
E7s and E6s had adequete enough horsepower where they hauled short passenger trains (7 cars or less) with little effort. Additional units on short passenger trains were usually found on railroads that had to tackle grades, like the Pennsylvania. The extra horsepower and braking were helpful.
If you have a chance, check out an LHS that regularly stock books from Don Ball. A number of his books have gorgeous photos of trains in the past. I purchased the book called “American Railroads”. Has many nice color shots of E units hauling passenger trains. Several of them singly.
Hope this helps!
Union Pacific used A-B-B, A-B-B-A, and A-B-B-B sets of E units. It all depends on the length of the train. Some railroads ran in A-A consists too.
from what I understand, not all roads that had E7’s A units even owned B units. The CB&Q would run a pair of A units “elephant style” with both facing forwards. In fact, my Burlington Route Historical Society calender has a photo from December 1969 showing a train headed up with 5 E units elephant style.
The PRR bought E7’s in double A units and soon found out they were inadequate for their trains so when they downrated the ten Alco PA’s they used the PBs with the two E7’s. By the way the first two E7’s arrived at the same time as the T1 steam engines and were assigned to Harrisburg as a base. They were used on the Detroit Arrow. After several months the EMD rep. told the PRR the wheels needed turning and they told him they must have been soft because none of the T1s were anywhere near needing wheel work. Reason - The most mileage on a T1 was 120,000 miles while the E units had burbled over 500,000 miles in the same time. It brought home dramatically the reliability of diesels and the maintenance of steam in ione lesson. Later the PRR would separate some pairs of E7s and use them singally on commuter runs and short trains.
Union Pacific for several years ran their Las Vegas Gamblers Special between Los Angeles and Las Vegas with a single E unit and five cars. Busy weekends and holidays a B unit was thrown in when the trained swelled in size.
Santa Fe ran their early E units and later E8 engines as single engine power on several trains including the San Diegans, the Golden Gates, and the locals throughout Texas.
Southern Pacific also assigned their single unit E7 diesels to the Oakland-Sacramento Senator trains, usually 5-6 cars being pulled on this short 100 mile hop.
DEPENDS on the railroad.and size of train.
For example S.P. at one time used ABA-7’s on their 'Daylight’s and Santa Fe ran E-1 / E-3 AB (no 7’s) or their Surfline (SD/LA) run.s.
Additional (probably marginally useless) information:
Specific example. Katy/Frisco never owned any E7B’s (for, for that matter, any B-unit E’s at all). Katy had a set of E7A’s for the Texas Special and Frisco had 3 sets of E7A’s–1 for the TS and 2 for the Meteor. They ran them back to back, as intended, until late in the game. In fact Katy had no EB units for pax service–only F7B’s and F9B’s, and in the later days the B’s got sandwiched between 2 E’s, 2 FP7’s or an E and an FP7. Once they got the E8’s, single units showed up a lot on the stub trains to FTW and HOU, including the TS E7’s, which had lost their TS lettering but still had the SS fluted sides. Frisco I think also soloed some of the E’s at various times, including on the Meteor. Frisco, of course, converted their 6 E7’s to the racehorse decor like the E8’s, and took the SS off the sides and put it on some modernized HW cars for the TS and Meteor.
The justification for more than one unit goes to both train length and terrain. On a relatively flat run like we have in parts of TX, an E can do just fine with 5-6 LW cars. You’d never get away with that on the PRR, B&O or C&O in the mountains. Example–I was in the Rio Grande Valley (flat as the proverbial pancake) the other day and UP was pulling about 100 auto racks with one 4400 HP unit. Seen the same thing on CSX/L&N on the gulf line and of course on everybody in FL. The justification for pax B unit F’s on ATSF and a couple others(TNO also did this) was that they didn’t buy FP7’s with the water tank capacity, the A unit F’s they had were without steam generators, so there would always be at least an A-B F unit combination. ATSF ran solo E’s and PA’s all over TX on their stubs (like 115/116, 75/76/77/78, etc).
TNO and SSW soloed PA’s all the time as the trains got shorter. When Russell emaciated the premium Sunbeam (TX Daylight) in 1955, the remaining 5 car train got a single PA until it came off. In fact SSW 107/108 to DAL were 4-6 HW HE and an Am
The prewar E6 and even E3 were also 2,000 hp units and they were used singly on many prewar streamlined trains. Initially the Rocky Mountain Rocket of the Rock Island. The SAL Silver Meteor and ACL Champions were both operated behind a single E unit before WW-II. The IC City of Miami was another single E6 unit train initially. These were all coach streamliners when first introduced. Other trains with single E units Henry M. Flagler of the FEC, CB&Q Silver Streak Zephyr, Sam Houston Zephyr. The latter two were stainless steel E5 units of the CB&Q. The Santa Fe operated single unit E1A units initially on the San Diegan, El Capitan , Golden Gates and Tulsan trains.
[;)]Also, don’t forget that in the 1960s as passenger service declined, several railroads found themselves with surpluses of E7s and E8s.
Quite a few of these E-units were used in fast freight service before being traded in on the newer locomotives that EMD and Alco were putting on the market.
They were used in conjunction with other locomotives as E-units were not very powerful freight haulers, however their speed gearing enabled them to be used on hot shot intermodals for a while.
Some years back I saw a short video clip of a long Seaboard fast freight with two E units in the lead running about 70 m.p.h! Looked impressive! [:D][8D][:p]
Thinking about trains pulled by single E units, C&O’s Grand Rapids-Detroit Pere Marquette streamliners also used single E7As.
Southern ran A-A consists, not sure if they had Bs
And now for the newbie question… What exactly does the B unit do??
Basically a “B” unit is just an “A” unit without a crew cab. Diesels are really “diesel-electrics” and are controlled electrically, so you can take say five diesels and couple them together and connected them m.u. cables ("Multiple Unit) and run all five from the lead engine’s cab. Both F unit (four axle) and E unit (six axle) General Motors diesels could be bought as A units (with cab) or B unit (without).
By about 1960 most railroads decided it was better to buy engines with cabs like GP or SD units and then any engine could be used as the lead engine.
For E units, it depended on the railroad and their wants/needs. Some roads liked to use back to back A-A units, that way they didn’t have to turn the engines at the terminal, since the train could be run from either engine. Some roads thought it looked better to run A-B sets as the B units blended cosmetically better with the passenger cars.
Great Northern bought A-A E unit sets in the forties when they streamlined the Empire Builder, I got to ride behind one pulling a 4 or 5 car “Badger” between Mpls/St.Paul and Duluth Superior in the late sixties. [:D]
BTW road could “mix and match”, the Rock Island Rocket in the sixties often had an E8A unit leading an E7B unit.
PC ran E units on their Flexi-Van trains for awhile. Both E7s and E8s were common sights after Amtrak took over most intercity trains. PC still ran E units on commuter trains. Some of these locomotives never received a coat of PC black, and continued to run in battered PRR or NYC colors, but with PC worms instead. Later, most of their E7s (except for the one in Strasburg) were scrapped, and the prime movers used in the RS3M rebuilding program. PC had a few E “B” units, but not many.
The CB&Q post WWII didn’t buy any B units nor any engines for their extensive Chicago commute operation. They were able to retire sbbn steam by scedulling periodic servicing for all thier psgr diesels @ Chicago. A train would arrive w/ 3 or 4 untits they would be assigned to 3 or 4 commuter trains, get serviced in Aurora, and work back to Chicago the next day and be assigened to on out bound main line train.
By the time the E-8s and E-9s were brought out most RRs didn’t want any B units and so there were only about 5 or 6 w/ E-8 or 9 Bs and most of them were rebuillds