Isthmian Canal Commission/Panama 2-6-4 "Adriatic" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class 101 (Locobase 11459)

Data from "Locomotive Building," The Railroad Gazette, Vol XXXIX, No 16 (20 October 1905), p 124, updated and corrected by "Panama Canal Engines", Railway and Locomotive Engineering (December 1905), p 537.

Photographs suggest that this small tank was a Mogul with a permanent bunker and tank. Additional water rode in the side tanks that ran forward from the roomy cab to just over the front driving axle. They were used as passenger locomotives during the construction of the Panama Canal to move the thousands of workers to and from their jobs.

Most or all were disposed of once the canal was opened in 1914. The Genesee & Wyoming operated #105 as 2-6-0 tender engine #15 on the standard gauge. The G & W website -- -- reports that this locomotive may never actually have served in Panama, but was sold to A B Shaw in 1905.

The perils of contemporary sourcing become apparent when comparing this set of specifications from the 20 October 1905 RG with those published in the same journal on 2 May of the same year. At that time they were projected to have 236 tubes and a total evaporative heating surface of 1,598 sq ft, but put less weight on the drivers and on the track as a whole. The December issue of R&LE, but says that the boiler will hold 320 tubes, a considerable overstatement.

Specifications by Steve Llanso of Sweat House Media
Locobase ID11459
RailroadIsthmian Canal Commission/Panama
Number in Class24
Road Numbers101-124
Number Built24
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase13.17'
Engine Wheelbase32.67'
Ratio of driving wheelbase to overall engine wheebase 0.40
Overall Wheelbase (engine & tender)32.67'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers124000 lbs
Engine Weight183500 lbs
Tender Light Weight
Total Engine and Tender Weight183500 lbs
Tender Water Capacity3700 gals
Tender Fuel Capacity (oil/coal)5 tons
Minimum weight of rail (calculated)69 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter54"
Boiler Pressure180 psi
Cylinders (dia x stroke)19" x 26"
Tractive Effort26594 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.66
Heating Ability
Firebox Area125.10 sq. ft
Grate Area26.20 sq. ft
Evaporative Heating Surface1497 sq. ft
Superheating Surface
Combined Heating Surface1497 sq. ft
Evaporative Heating Surface/Cylinder Volume175.45
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation4716
Same as above plus superheater percentage4716
Same as above but substitute firebox area for grate area22518
Power L14030
Power MT214.95

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