Rock Island / Burlington, Cedar Rapids & N 4-4-2 "Atlantic" Type Locomotives

Class A-24 (Locobase 4121)

Described briefly in Railroad Gazette (13 December 1901) and more fully on 26 April of the same year, these were "Chatauqua" engines, which was a then-common alternative to "Atlantic" RG noted that the sextet was "doing very good work, sometimes hauling passenger trains of 14 cars on a quick schedule, with no difficulty in feeding the boiler sufficiently with one No. 9 injector. They have made a record for being 'smart' and economical."

RG gives total heating surface as 2,806 sq ft and the grate area as 55.70 sq ft. The total engine weight was given as 167,000 lb. The 1903 Rock Island locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection shows different heating surface dimensions from the RG article and they are the ones used in the specifications.

Builder info from B.Rumary, 25 Kingscombe, Gurney Slade, Radstock, BA3 4TH, ENGLAND and Jeremy Lambert as supplied by Allen Stanley in March 2004. Works #3766 in February 1901, 3825 (April 1901), 3911-3914 (July 1901)

Class A-24 (Locobase 5358)

Data from table in June 1906 AERJ. Drury (1993) says that the first pair of this balanced-compound class -- 1048-1049 -- arrived in 1905. The inside HP cylinders drove the first axle, the outside LP cylinders worked on the second set of drivers. The design met the requirements satisfactorily enough to lead to the purchase of 6 more (1042-1047) in 1906.

By the end of the Nineteen teens, however, the Rock Island decided to simplify and superheat the class; the result is shown in Locobasd 8355.

Class A-24 (Locobase 5359)

Data from table in June 1906 AERJ. The table has no square footage allotted for a superheater and the diameter of the flues is relatively small for this period. The 1903 Rock Island locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection credits them with "Alco" superheater and gives the surface area.

Drury (1993) notes that 8 of these were delivered with slide valves, two with piston valves. The specs probably refer to the piston-valved pair.

Like the road's other Atlantics, this class left service only in 1935-1937.

Class A-29 (Locobase 107)

Balanced simple engines with two cylinders inside and two outside, all driving the leading set of drivers. The four-cylinder, line-abreast layout on a rigid wheelbase was rare in the US, but used often in Britain through the first three decades of the twentieth century. These two engines stayed in service until the mid-1930s.

According to later Rock Island locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection, by 1937 these locomotives had larger superheaters with 582 sq ft of surface area.

Class Chatauqua (Locobase 3876)

Railroad Gazette (30 November 1900) describes these powerful Chautauquas as "having the general characteristics of the Atlantic type." Clearly, the latter name was more widely used. They had Player-Belpaire boilers and 10" piston valves.

Angus Sinclair, writing in the January 1901 Locomotive & Railway Engineering, made a reasonable prediction:"We think that this type of engine is destined to become very popular for the service for which this one was built, because it enables the designers to put in a very large firebox, and to make it deep enough so that it can be fired with sufficient

depth of combustible to ensure a high firebox temperature."

Builder info from B.Rumary, 25 Kingscombe, Gurney Slade, Radstock, BA3 4TH, ENGLAND and Jeremy Lambert as supplied by Allen Stanley in March 2004. Works #3642, 3668-3669. Also see RI 11 = 1903 Locomotive Classification and Diagrams supplied by Stanley in May 2005.

The B, CR & N was absorbed by its controlling railroad -- the Chicago, Rock Island and Pacific in 1903, at which point these three Atlantics became 1001, 1003, 1002, respectively. They carried on until the 1930s.

Specifications
Class	A-24	A-24	A-24	A-29	Chatauqua
Locobase ID	4121	5358	5359	107	3876
Railroad	Rock Island (CRI & P)	Rock Island (CRI & P)	Rock Island (CRI & P)	Rock Island (CRI & P)	Burlington, Cedar Rapids & N (CRI & P)
Whyte	4-4-2	4-4-2	4-4-2	4-4-2	4-4-2
Road Numbers	1004-1010	1042-1049	1011-1020	1040-1041	77
Gauge	Std	Std	Std	Std	Std
Builder	Brooks	Burnham, Williams & Co	Alco-Schenectady	Alco-Schenectady	Brooks
Year	1900	1905	1905	1910	1900
Valve Gear	Stephenson			Walschaert	Stephenson
	Locomotive Length and Weight
Driver Wheelbase	7'	6.83'	7'	7'	6.75'
Engine Wheelbase	28.67'	30.25'	27.45'	23.80'	27'
Ratio of driving wheelbase to overall engine wheebase	0.24	0.23	0.26	0.29	0.25
Overall Wheelbase (engine & tender)	53.71'		57.17'	62.67'	52.94'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers	87000 lbs	102000 lbs	107100 lbs	116000 lbs	88000 lbs
Engine Weight	162000 lbs	195000 lbs	191300 lbs	202000 lbs	158600 lbs
Tender Light Weight	110000 lbs	144000 lbs	144000 lbs	149900 lbs	107000 lbs
Total Engine and Tender Weight	272000 lbs	339000 lbs	335300 lbs	351900 lbs	265600 lbs
Tender Water Capacity	5500 gals	7000 gals	7000 gals	7500 gals	5000 gals
Tender Fuel Capacity (oil/coal)	10 tons	12 tons	12 tons	tons	10 tons
Minimum weight per yard of rail on which locomotive could run	73 lb rail	85 lb rail	89 lb rail	97 lb rail	73 lb rail
	Geometry Relating to Tractive Effort
Driver Diameter	78.50"	73"	73"	73"	75"
Boiler Pressure	200 psi	220 psi	185 psi	160 psi	210 psi
Cylinders (dia x stroke)	20.25" x 26"	15" x 26"	21" x 26"	17.5" x 26" (4)	19.5" x 26"
Tractive Effort	23089 lbs	22038 lbs	24699 lbs	29668 lbs	23530 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort)	3.77	4.63	4.34	3.91	3.74
	Heating Ability
Firebox Area	220.70 sq. ft	194 sq. ft	161.80 sq. ft	194.50 sq. ft	155.80 sq. ft
Grate Area	55.70 sq. ft	50.20 sq. ft	44.80 sq. ft	42.80 sq. ft	45.32 sq. ft
Evaporative Heating Surface	2851	3242	2389	2716	2552
Superheating Surface			339	479
Combined Heating Surface	2851	3242	2728	3195	2552
Evaporative Heating Surface/Cylinder Volume	294.17	609.65	229.21	187.62	283.96
	Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation	11140	11044	8288	6848	9517
Same as above plus superheater percentage	11140	11044	9117	7533	9517
Same as above but substitute firebox area for grate area	44140	42680	32926	34232	32718
Power L1	10677	7632	13495	10757	9729
Power MT	541.12	329.91	555.58	408.88	487.47