A 'bank engine' (
United Kingdom/
Australia) or 'helper engine' (
North America) is a railway locomotive that is temporarily attached to a
train that requires more power or
traction to climb a
grade (or ''bank''). They are most commonly found in mountain divisions (called "helper districts" in the U.S.).
Usage
Bankers or helpers were historically attached at the rear of the train, in which case they also protect against
wagons or
coaches breaking away from the train and running back downhill. Placing them at the rear also made it possible for the helper/banker to easily uncouple once the train had crested the grade. Once uncoupled, the engine would return to a siding or stub so as to clear the mainline and get ready for the next train.
Since it was not possible to remotely control a steam locomotive, each helper/banker had to have a full crew on board. Careful coordination was required between crews to assure that all locomotives were operated in a consistent manner. Standard whistle signals were employed to tell the helper crew when to apply power,
drift or
brake. A misunderstanding of signals by a pusher locomotive crew could result in a fearsome wreck if the lead locomotive applied brakes while the helper was still applying power. The usual result was that the train would experience a violent run-in, resulting in the derailment of a large number of cars.
In modern practice, helpers/bankers are often placed in the middle of the train and controlled by coded radio signals from the locomotive at the head end of the train, allowing one engineer (driver) to simultaneously control the helper(s) and main consist. This arrangement has the distinct advantage of applying the helper power to only part of the train, thus limiting the maximum drawbar pull applied to the first car of the train to a safe level.
In the UK, an engine that is attached to the front of a train to assist with the ascent of an incline is called a ''pilot locomotive''. In the United States a "double header" or "Three header", etc. would refer to the number of engines placed at the front of the train.
Helper, Utah was named after these engines, as it was where helper engines were kept to assist on the climb to
Soldier Summit.
Where
steam traction was utilised, it was common practice to use bank engines on significant gradients. However, since the introduction of
advanced braking systems and
diesel or
electric locomotives, bankers or helpers are now only required on a few very steep lines.
Examples
The following are locations where bankers are, or were, frequently required:
Australia
★
Ardglen
★
Cowan bank
★
Tumulla
Europe
★
Gotthard line - Frequent electric banking services for freight trains,
SBB-CFF-FFS and others
★
Lötschberg line - Frequent electric banking services until the opening of the
Lötschberg Base Tunnel in June 2007; future unknown yet;
BLS,
SBB-CFF-FFS and others
★
Monte Ceneri Pass line - Frequent electric banking services,
SBB-CFF-FFS and others
New Zealand
★ Reefton saddle on the
Stillwater - Westport Line
★
Wellington and Manawatu Railway Company between
Wellington and
Paekakariki
★
Otira Tunnel, between
Arthur's Pass and
Otira on the
Midland Line, after the removal of
electrification
United Kingdom
★
Ilfracombe branch line (1-in-36) – Steam until
1964
★
Lickey Incline
★
Peak Forest,
Derbyshire –
Steam then
diesel until late
1980s
★ The
Buxton Line in
Derbyshire
★
Whiteball Bank,
Somerset
★ Worsbrough Bank,
South Yorkshire – Steam until
1953 then Electric until
1981
United States and Canada
★
Cajon Pass – BNSF Railway Company, ex-Atchison, Topeka, and Santa Fe
★
Cuesta Grade – Union Pacific, ex-Southern Pacific
★
Donner Pass – Union Pacific, ex-Southern Pacific
★
Galitzin Summit – Norfolk Southern, ex-Pennsylvania Railroad, ex-Penn Central, ex-Conrail
★
Kicking Horse Pass – Canadian Pacific Railway Company
★
Marias Pass – BNSF Railway Company, ex-Great Northern, ex-Burlington Northern
★
Moffat Tunnel Line – Union Pacific, ex-Denver and Rio Grande Western
★
Mullen Pass – Montana Railink, ex-Northern Pacific, ex-Burlington Northern
★
Raton Pass – BNSF Railway Company, ex-Atchison, Topeka, and Santa Fe
★
Saluda Grade – Norfolk Southern, ex-Southern. The steepest grade in North America at 5.03%. Currently out of service. The trailing end of a three car passenger train would be completely above the locomotive.
★
Sand Patch Grade – CSX Transportation, exx-Baltimore & Ohio, ex-Chessie System
★
Soldier Summit – Union Pacific, ex-Denver and Rio Grande Western
★
Tehachapi Loop – Union Pacific, ex-Southern Pacific
★
Tennessee Pass – Union Pacific, ex-Denver and Rio Grande Western
See also
★
Assisting engine
★
Double-heading
★
Station pilot
External links
★
Ghost Depot's entry for Soldier Summit. This page has a photo of a 4-header train with rear helper on the western approach to Soldier Summit