my ESPEE MODELERS ARCHIVE

California's Railroad to the U.S. 1861 - 1996

Southern Pacific
PA1 / PB1 - PA2 / PB2

6005 - 6016, 6018 - 6045

5910 - 5915, 5918 - 5924

39 PA's units delivered

13 PB's units delivered

Don't even bother reading this page! buy this Book - "PA - ALCo's Glamour Girl by Andy Romano" - 28 color photo's of every SP paint scheme plus one I had not heard of before, plans, rosters, in fact the whole enchilada...

The term PA3/PB3 has evidently been erroneous. ALCo apparently never having used PA3/PB3 officially. To that end all references to PA3/PB3 have been changed to read PA2/PB2.

Southern Pacific's PA diesel locos, came in three main flavors, SP/SSW/T&NO, and variations abound within these three groups .

Southern Pacific received their first PA1/PB1's in 1948, delivered in 3 unit sets numbered 6005 ABC to 6007 ABC. These were equipped with retractable front couplers, which didn't last long, and ATS (Automatic Train Stop)

Another 9 were delivered in 1949, 6008 ABC thru 6010 ABC. These came with the 'standard' ALCo pilot and ATS.

After 1949 the letter suffixes were dropped, and the PA's renumbered 6005 thru 6016. The PB's were renumbered 5910 thru 5915.

In 1950 four PA2's (6019 - 6022) and 2 PB2's (5918, 5919) were delivered, Basically the same appearance as the PA1/PB1's, they came with larger (4500 lb/hr) steam generators and ATS.

1952 saw another 5 PA2's (6023 - 6027) and 2 PB2's (5920, 5921), these and subsequent orders of PA's came without pilots, and SP fitted plow pilots built by Sacramento General Shops. These were also the first PA's to have factory fitted nose MU sockets.

6 more PA2's came in 1953 (6028 - 6033) and 3 PB3's (5922 - 5924). These PA's were the first without the curved drip strip over the cab side windows, and no rear porthole, but did have 5 chime horns instead of three chime horns.

The final additions were 12 PA2's delivered late 1953 (6034 - 6045), identical to the previous PA2's, and like all other SP PA's they also had ATS.

The PA2/PB2's had 250 hp more than the 2000 hp PA1/PB1's, but this was only available at higher speeds than SP ran their trains. So as they were in effect, rated the same as the PA1/PB1's, SP called them all PA1/PB1's.

Starting in 1956, all PA/PB's were rebuilt/upgraded. Work may have included:

• losing the curved drip strip/drain gutter,
• plating over of portion of the side grilles,
• losing the last porthole,

builders photo of SP PB #6005b from George Paine

All SP PA/PB's were delivered in Daylight paint, beginning in 1959 they were repainted to the scarlet and grey scheme. Before that though;

Paint Variations:

• Halloween:
  • PA2 6039 received orange and black paint in the bow wave scheme,
  • PA2 6024 also got the orange and black, but the orange was the exact shape the later red wings would be,
  • PB2 5922 received solid black,
• Half Widows
  • 6034 was painted in the Bloody Nose scheme but with black instead of gray
• Bloody Nose
  • 6056 when painted in the scarlet and grey, had Gothic 'Southern Pacific' lettering applied, instead of the more standard Railroad Roman.
  • 6063 when painted in the scarlet and grey, had Gothic 'Southern Pacific' lettering applied, instead of the more standard Railroad Roman.

There is a persistent rumor that one or two PA's were painted in the Black Widow scheme. However no proof has surfaced that this was in fact true.

see also: SSW PA/PB's

see also: TNO PA's

Prototype References:

• Southern Pacific Historic Diesels, Volume 9, Alco PA/PB Passenger Locomotives - by Joe Strapac.
• Diesel Era May/June 2002 Vol.13 No.3 - 15 pages of info photos and rosters
• Diesels of the SP, Vol 1, Alco PA's - (there were no more Volumes)
• SP Dieselization by John Bonds Garmany
• PA ALCo's Glamor Girl by Andy Romano - 28 color photo's (and that is just the SP stuff), plans, rosters
• Southern Pacific Motive Power Review 1967-68 by Joe Strapac
• Southern Pacific Motive Power Review 1978-79 by Joe Strapac
• Southern Pacific Motive Power Review 1983-85 by Joe Strapac

Additional S Scale info courtesy James Baglien.