Southern Pacific Class AC-11

Southern Pacific class AC-11
SP 4274
Technical specifications
Serial number(s)	64677-64706
Manufacturer(s)	Baldwin Locomotive Works
Build date	November 1942 - April 1943
Total produced	29
Classification	AC-11
Wheel arrangement	4-8-8-2
Rail gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Boiler pressure	250 psi (1.7 MPa)
Bore stroke	24 in × 32 in (610 mm × 813 mm) (bore × stroke)
Fuel type	Fuel oil
Performance figures
Tractive effort	124,300 lbf (553 kN)
Service information
Running numbers	4245-4274
Disposition details
Preserved	None were preserved
Disposition	All scrapped

Southern Pacific Railroad's AC-11 Class (meaning Articulated Consolidation) of cab forward steam locomotives was the seventh class of 4-8-8-2 locomotives ordered by Southern Pacific (SP) from Baldwin Locomotive Works; SP was so pleased with the AC-10 class built a year earlier that the railroad began placing orders for AC-11s while the AC-10s were still being built and delivered. They were built between November 1942 and April 1943, closely resembling the AC-10s.

The first AC-11, number 4245, entered service on November 24, 1942, and the last, 4274, on May 9, 1943. SP used these locomotives for between 12 and 15 years, with the last retirements from this class occurring on September 24, 1958. Shortly after their retirement, the AC-11s were scrapped, with the last, number 4274, on April, 1959.

None of the members of this class were preserved.

Incidents

In January 1952, No. 4245 was used in an unsuccessful attempt to rescue the snowbound City of San Francisco passenger train, which was trapped in 12-foot drifts by a heavy blizzard at Yuba Pass, 17 miles west of Donner Pass and 5 miles east of Emigrant Gap in the Sierras. Attempting to reach the stuck train with snow fighting equipment, the engine along with the steam-driven rotary snowplow that it was pushing were hit by an avalanche, derailing and becoming trapped as well. Later, they were hit by a second, larger avalanche, which overturned the plow and its tender, killing No. 4245's engineer, Rolland "Rolly" Raymond, who at that point had been outside standing next to it, becoming one of only two casualties in the incident. The second SP worker to die, Jay Gold, succumbed to a stress-induced heart attack from the physical exertion of the rescue effort.

Stock list

Image	Loco No.	Build date(s)	Builder	Status	Notes
	4245	November 1942	Baldwin Locomotive Works	Scrapped	Involved in an avalanche incident, repaired and returned to service, and was scrapped after it was retired.
	4246		Baldwin Locomotive Works	Scrapped
	4247		Baldwin Locomotive Works	Scrapped
	4248		Baldwin Locomotive Works	Scrapped
	4249		Baldwin Locomotive Works	Scrapped
	4250	-	Baldwin Locomotive Works	Scrapped
	4251		Baldwin Locomotive Works	Scrapped
	4252		Baldwin Locomotive Works	Scrapped
	4253		Baldwin Locomotive Works	Scrapped
	4254		Baldwin Locomotive Works	Scrapped
	4255		Baldwin Locomotive Works	Scrapped
	4256		Baldwin Locomotive Works	Scrapped
	4257		Baldwin Locomotive Works	Scrapped
	4258		Baldwin Locomotive Works	Scrapped
	4259		Baldwin Locomotive Works	Scrapped
	4260		Baldwin Locomotive Works	Scrapped
	4261		Baldwin Locomotive Works	Scrapped
	4262		Baldwin Locomotive Works	Scrapped
	4263		Baldwin Locomotive Works	Scrapped
	4264		Baldwin Locomotive Works	Scrapped
	4265		Baldwin Locomotive Works	Scrapped
	4266		Baldwin Locomotive Works	Scrapped
	4271	1943	Baldwin Locomotive Works	Scrapped
	4272	1943	Baldwin Locomotive Works	Scrapped
	4273	1943	Baldwin Locomotive Works	Scrapped
	4274	April 1943	Baldwin Locomotive Works	Scrapped	Selected for an excursion train run over Donner Pass, retired from active service and scrapped.

Gallery

A model of what No. 4245 looked like

4245 trapped in the snow after derailing at Yuba Pass. January 1952

Cab forward steam locomotives of the Southern Pacific Railroad
2-6-6-2	MM-2
4-6-6-2	AM-2
2-8-8-2	MC-1 • MC-2 • AC-1 • MC-4 • AC-2 • MC-6 • AC-3
4-8-8-2	AC-4 • AC-5 • AC-6 • AC-7 • AC-8 • AC-10 • AC-11 • AC-12
Preserved	SP 4294 (AC-12)