Western Maryland Scenic Railroad 1309

Specifications
Specifications
Configuration:;
• Whyte	2-6-6-2
Gauge	4 ft 8+1⁄2 in (1,435 mm)
Leading dia.	30 in (762 mm)
Driver dia.	56 in (1,422 mm)
Trailing dia.	44 in (1,118 mm)
Minimum curve	20°
Wheelbase	48.8 ft (14.87 m)
Length	99.7 ft (30.39 m)
Height	15 ft (4.57 m)
Adhesive weight	366,700 lb (166,332 kg)
Loco weight	434,900 lb (197,267 kg)
Tender weight	208,200 lb (94,438 kg)
Total weight	643,100 lb (291,705 kg)
Tender type	12-RC
Fuel type	Soft coal
Fuel capacity	15 short tons (14 t)
Water cap.	12,000 US gal (45,425 L; 9,992 imp gal)
Firebox:
• Grate area	72.2 sq ft (6.71 m2)
Boiler	96 in (2,438 mm)
Boiler pressure	210 psi (1.45 MPa)
Heating surface:
• Firebox	363 sq ft (33.7 m2)
• Tubes and flues	4,436 sq ft (412.1 m2)
• Total surface	4,825 sq ft (448.3 m2)
Superheater:;
• Type	Type A
• Heating area	975 sq ft (90.6 m2)
Cylinders	Four, compound: LP front, HP rear
High-pressure cylinder	22 in × 32 in (559 mm × 813 mm)
Low-pressure cylinder	35 in × 32 in (889 mm × 813 mm)
Valve gear	Walschaerts
Valve type	Piston valves
Valve travel	6+1⁄2 in (165 mm) (HP) ; 6 in (152 mm) (LP)
Valve lap	1 in (25 mm) (HP) ; 1+1⁄8 in (29 mm) (LP)
Valve lead	1⁄8 in (3 mm) (HP) ; 3⁄16 in (5 mm) (LP)
Loco brake	Air
Train brakes	Air

Type and origin
Type and origin
Power type	Steam
Builder	Baldwin Locomotive Works
Order number	48001
Serial number	74278
Model	H-6
Build date	November 1949

Western Maryland Scenic Railroad 1309
Western Maryland Scenic Railroad 1309
	No. 1309 heading to Cumberland, Maryland with the Frostburg Flyer excursion in August 2022
Power type
Type and origin
Power type	Steam
Builder	Baldwin Locomotive Works
Order number	48001
Serial number	74278
Model	H-6
Build date	November 1949
Configuration:;
Specifications
Configuration:;
• Whyte	2-6-6-2
Gauge	4 ft 8+1⁄2 in (1,435 mm)
Leading dia.	30 in (762 mm)
Driver dia.	56 in (1,422 mm)
Trailing dia.	44 in (1,118 mm)
Minimum curve	20°
Wheelbase	48.8 ft (14.87 m)
Length	99.7 ft (30.39 m)
Height	15 ft (4.57 m)
Adhesive weight	366,700 lb (166,332 kg)
Loco weight	434,900 lb (197,267 kg)
Tender weight	208,200 lb (94,438 kg)
Total weight	643,100 lb (291,705 kg)
Tender type	12-RC
Fuel type	Soft coal
Fuel capacity	15 short tons (14 t)
Water cap.	12,000 US gal (45,425 L; 9,992 imp gal)
Firebox:
• Grate area	72.2 sq ft (6.71 m2)
Boiler	96 in (2,438 mm)
Boiler pressure	210 psi (1.45 MPa)
Heating surface:
• Firebox	363 sq ft (33.7 m2)
• Tubes and flues	4,436 sq ft (412.1 m2)
• Total surface	4,825 sq ft (448.3 m2)
Superheater:;
• Type	Type A
• Heating area	975 sq ft (90.6 m2)
Cylinders	Four, compound: LP front, HP rear
High-pressure cylinder	22 in × 32 in (559 mm × 813 mm)
Low-pressure cylinder	35 in × 32 in (889 mm × 813 mm)
Valve gear	Walschaerts
Valve type	Piston valves
Valve travel	6+1⁄2 in (165 mm) (HP) ; 6 in (152 mm) (LP)
Valve lap	1 in (25 mm) (HP) ; 1+1⁄8 in (29 mm) (LP)
Valve lead	1⁄8 in (3 mm) (HP) ; 3⁄16 in (5 mm) (LP)
Loco brake	Air
Train brakes	Air
Tractive effort
Performance figures
Tractive effort	98,300 lbf (437.26 kN) (simple) ; 77,900 lbf (346.52 kN) (compound)
Factor of adh.	3.73 (simple) ; 4.7 (compound)
Operators
Career
Operators	Chesapeake and Ohio Railway; Western Maryland Scenic Railroad;
Class	H-6
Number in class	10
Numbers	C&O 1309; WMSR 1309;
Nicknames	Maryland Thunder; Super Choo;
Retired	1956
Preserved	1972
Restored	December 31, 2020
Current owner	Western Maryland Scenic Railroad
Disposition	Operational
	References:

Western Maryland Scenic Railroad 1309 (officially nicknamed Maryland Thunder) is a preserved compound articulated H-6 class 2-6-6-2 "Mallet" steam locomotive. It was the very last steam locomotive for domestic service built by Baldwin Locomotive Works (BLW) in November 1949 and originally operated by the Chesapeake and Ohio Railway (C&O) where it pulled coal trains until its retirement in 1956.

In 1972, No. 1309 was moved to the B&O Railroad Museum for static display until 2014 when it was purchased by the Western Maryland Scenic Railroad (WMSR), who undertook a multi-year effort to restore it to operating condition. The restoration was completed on December 31, 2020, and the locomotive entered tourist excursion service for the WMSR on December 17, 2021. This was the first time an articulated locomotive operated in the Eastern United States since the retirement of Norfolk and Western 1218 in November 1991.

As of 2026, No. 1309 is currently operational on the WMSR roster. Additionally, it is one of only two surviving H-6's, the other of which is Chesapeake and Ohio 1308, which is on static display at the Collis P. Huntington Railroad Historical Society and then the Age of Steam Roundhouse Museum.