Westinghouse Air Brake, One Of Railroads Most Important Inventions
Last revised: September 9, 2024
By: Adam Burns
The Westinghouse Automatic Air Brake was one of the most important improvements in railroad safety during the industry's early years.
Developed by George Westinghouse in the 1860s, just after the Civil War, it also offered more efficient operations since brakemen no longer had to engage in the dangerous, tedious task of navigating the catwalks and setting brakes manually.
The automatic system used pressurized air contained within the locomotive and each car to quickly applying braking throughout the train.
As was so often the case during those times railroads were slow to adopt the practice despite its advantages until being forced to do so by the government. Today, air brakes remain the primary method to stop a train throughout North America.
Photos
Rio Grande F9A #5771 is stopped at Winter Park, Colorado with the "Ski Train," circa 1984. Mike Bledsoe photo. American-Rails.com collection.History
When the railroad began to flourish in a young United States the prospects of this fast new mode of transportation were tantalizing.
According to John Stover's book, The Routledge Historical Atlas Of The American Railroads, travel time by stagecoach or horseback from New York City to the Ohio River normally required 2 to 3 weeks to cover the 400+ miles.
With railroads this was reduced to single day by the 1860s. Despite their economic and societal improvements the railroad's its early years were fraught with problems, beginning with safety.
With little government oversight in the early 19th century (many laws and regulatory agencies did not appear until the late 1800s) railroads were free to do as they pleased. The issue of braking was one such area the industry did not bother addressing.
Early Brakes
To stop trains a very rudimentary, inefficient, and dangerous method was employed requiring employees known as brakeman to run atop the cars and set each car's brakes by hand using its brake-wheel.
According Jim Boyd's book, The American Freight Train, the first types of rolling stock to use them were simple gravity cars of the 1830s which employed basic brake shoes that would press against the wheel retarding its movement.
In addition, the first locomotives carried their own rudimentary system, which also sometimes forced a brakeman to climb atop the contraption and apply its brakes.
When stopping a moving train the engineer would signal via the locomotive's whistle and brakemen would climb on each car's roof and manually apply its brake-wheel.
The worker would run from car to car doing until he had set all of the required brakes. It was a very dangerous occupation that resulted in many injuries and deaths.
Rio Grande F7A #5724 at the Burnham Yards and Shops in Denver, Colorado, circa 1970. Robert Eastwood, Jr. photo. American-Rails.com collection.George Westinghouse
As Mr. Boyd notes it was also very time consuming, requiring a few minutes to stop a train going just 15 mph. In some instances engineers could see their approaching trains but could not stop in time to avoid a collision.
According to the book, Railroads In The Days Of Steam (from the editors of American Heritage), a young Union Army veteran named George Westinghouse hoped to fix this problem, improve safety, and save lives.
He was particularly disturbed by the incident mentioned above which had occurred near Schenectady, New York. After some time he received a patent for an automatic air brake on April 13, 1869.
His design utilized a triple valve system which included a piston valve, slide valve, and graduating valve. To increase a train's stopping time Westinghouse equipped each car with its own air reservoir (tank).
Kansas City Southern's only S2, #1114 (a former Kansas City Terminal unit), was photographed here in Kansas City, Missouri, circa 1968. American-Rails.com collection.Once activated from the locomotive cab it operated on a fail-safe system; the line, interconnected throughout the train by sealed pipes running underneath each car would release its air at a controlled rate, thus reducing the pressure which then triggered a valve system on each car to feed air into the brake cylinder.
After the engineer released the brake, the valve portal would close and each car's tank refilled with air.
This increase in air pressure subsequently caused each car's valves to work in reverse, allowing the brake cylinders to release their pressure.
During an emergency situation, such as a rapid loss of pressure via a damaged line or the engineer manually "dumping the air," braking is rapidly applied throughout the train. It was an ingenious system but, not surprisingly, railroads were skeptical.
Missouri Pacific SD40-2's with the Barnum & Bailey "Circus Train" at Taylor, Texas, circa 1982. Mike Bledsoe photo. American-Rails.com collection.As the Cornelius "Commodore" Vanderbilt told Westinghouse, "Do you pretend to tell me that you could stop trains with air?"
He proved the legendary tycoon wrong (who laid the foundation for what eventually became the mighty New York Central System) during a demonstration run from Pittsburgh, Pennsylvania to Steubenville, Ohio.
During the test he placed an air pump and tank on the lead locomotive and then ran pipes to every trailing car. Each had its own cylinder and piston connected to a braking system and once activated by the engineer the compressed air quickly applied braking throughout the train.
This initial design did not employ a fail-safe system so if the line was cut or there was a leak the resulting loss of pressure would cause the brakes to fail.
In 1872 Westinghouse improved upon his initial design, which is mentioned above. Unfortunately, even this demonstration did not fully convince railroads.
Chicago, Burlington & Quincy 4-8-4 #5614 was photographed here near the end of her career in the summer of 1956. The locomotive was built by Burlington's shop forces in 1937. Following her career she was donated to the city of St. Joseph, Missouri in May, 1962. American-Rails.com collection.Railway Safety Appliance Act
The issue largely came down to money as companies did not want to spend the large sums of capital required to upgrade their equipment with the new device.
During the 1880s the first legislation was enacted when Iowa, led by state railroad commissioner Lorenzo Coffin, passed a measure to have all trains operating within its state equipped with both automatic air brakes and Eli Janney's new knuckle coupler.
Finally, Congress passed the Railway Safety Appliance Act in 1893 requiring all railroad equipment utilize the braking system.
Westinghouse went on to establish his Westinghouse Air Brake Company in 1869 and today railroads in the United States continue to use the basic system although many improvements have been made over the years (worldwide other countries have adopted a pneumatic system, such as in Britain and Germany).
Sources
- Boyd, Jim. American Freight Train, The. Osceola: MBI Publishing, 2001.
- McCready, Albert L. and Sagle, Lawrence W. (American Heritage). Railroads In The Days Of Steam. Mahwah: Troll Associates, 1960.
- Stover, John. Routledge Historical Atlas of the American Railroads, The. New York: Routledge, 1999.
Recent Articles
-
Union Pacific 2-10-2 5511 Passes Its First Steam Test
Nov 12, 26 12:12 AM
Union Pacific 2-10-2 5511 passed a steam test at Silvis, Illinois. Railfan and Railroad reports a summer 2027 target. A November 6 Trains report had no immediate operating plan. -
Union Pacific Steam Roster
Nov 12, 26 12:03 AM
Union Pacific steam locomotives built since 1900. Oregon Short Line, Los Angeles and Salt Lake, and Oregon-Washington Railroad and Navigation Company numbers, with the 4-12-2s, Challengers, Big Boys… -
Union Pacific Railroad: Map, History, Logo
Nov 11, 26 11:56 PM
The Union Pacific, from the Pacific Railway Act of July 1, 1862, and Promontory Summit on May 10, 1869, through E. H. Harriman and the mergers that built the modern railroad. Steam and diesel rosters… -
Texas and Pacific Railway: Map, History, Timetables
Nov 10, 26 10:33 PM
The Texas & Pacific Railway, the federally chartered southern transcontinental that stopped at Sierra Blanca and became the Missouri Pacific's Texas and Louisiana main line. Merged October 15, 1976. -
Texas and Pacific Steam Locomotives: Texas Types and Mountains
Nov 10, 26 10:30 PM
Texas & Pacific steam: 70 Lima 2-10-4 Texas types, 600-669, classes I-1 through I-1d, and 10 Mountains, 900-909. No. 610 is at Palestine. -
Texas and Pacific Diesel Roster (All-Time)
Nov 10, 26 10:29 PM
All-time diesel roster of locomotives built for the Texas & Pacific. 246 units: E7s, E8s, 83 F7A and 35 F7B, NW2s, SW7s, SW8s, SW9s, GP7s, GP9s, GP18s, and GP35s. Serials and order numbers. -
Santa Fe-Southern Pacific Railroad: Merger, History, Paint Scheme
Nov 10, 26 10:07 PM
The proposed Santa Fe-Southern Pacific merger, from the 1980 attempt and the 1983 holding company through the ICC denial, the Kodachrome paint, and the sale of the Southern Pacific. -
CSX Santa Train Will Feature Locomotives 250 and 2026
Nov 10, 26 01:51 PM
The CSX Santa Train will feature locomotives 250 and 2026 on November 21, 2026. The 84th running covers 110 miles from Shelbiana, Kentucky, to Kingsport, Tennessee. -
Denton County Asks to Extend Stadler Car Relief
Nov 10, 26 01:05 PM
Denton County Transit Authority has asked the FRA to extend a waiver for its Stadler diesel multiple-unit cars. Comments run to January 11, 2027. -
FreightCar America Reports Third-Quarter Results
Nov 10, 26 01:02 PM
FreightCar America reported third-quarter revenue of $76.5 million and 662 railcar deliveries. Backlog stood at 2,660 cars valued at $284.5 million. -
Amtrak Has Filed a Train Control Amendment
Nov 10, 26 12:53 PM
Amtrak asked the FRA on October 26, 2026, to amend the safety plan for its Interoperable Electronic Train Management System. Comments are due November 30, 2026. -
SunRail Signal Waiver Is Open for Comment
Nov 10, 26 12:25 PM
FRA has asked for comment on a petition to extend signal-testing relief on the Central Florida Rail Corridor. The notice names both the corridor and CSXT. Comments run to January 11, 2027. -
Cars and Units Rose With BNSF Third-Quarter Earnings
Nov 10, 26 12:18 PM
Berkshire Hathaway reports that after-tax BNSF earnings increased 19.3 percent in the third quarter of 2026, with car and unit volumes up 3.9 percent. -
Amtrak Chicago Platforms Are Moving Toward Level Boarding
Nov 10, 26 12:13 PM
Amtrak says construction is underway soon on the first level boarding platforms at Chicago Union Station, a 112 million dollar, 30-month project. -
Maryland Has New Penn Line Times on November 16
Nov 10, 26 12:07 PM
MARC Penn Line schedules change on November 16, 2026, after Amtrak trains return to regular schedules. Weekend southbound trains are unchanged. -
Building Contract for Metrolink Sidings Goes to Granite
Nov 10, 26 12:00 PM
Granite says Metrolink awarded a 51.5 million dollar SCORE contract for sidings near downtown Los Angeles and in Rancho Cucamonga. -
EMD "F2" Locomotives: Specs, Roster, History
Nov 10, 26 12:22 AM
EMD F2, the 1,350-horsepower bridge between the FT and the F3. 104 locomotives, July through November 1946. Spotting features, specifications, and the production roster. -
Southern Pacific Diesel Roster (All-Time)
Nov 10, 26 12:08 AM
Southern Pacific diesel roster with builder serials, order numbers, Texas and New Orleans numbers, and the 1965 renumbering. Alco, Baldwin, Fairbanks-Morse, Electro-Motive, General Electric, Krauss-Ma… -
Southern Pacific Steam Roster: Post 1900
Nov 09, 26 11:56 PM
Southern Pacific steam locomotives built since 1900. Pacific Lines, Texas and Louisiana Lines, cab-forwards, the GS 4-8-4s, and five narrow-gauge Ten-Wheelers. The quantity column counts the rows as p… -
Canal Street Yard Assessment Stays Open Through December 7
Nov 09, 26 01:07 PM
The FRA signed the Canal Street Yard environmental assessment on November 6, 2026. Public inspection runs through December 7, and meeting dates are not confirmed. -
NS Legacy Cab-Signal Comments Are Due November 9
Nov 09, 26 01:05 PM
The FRA must receive comments by November 9, 2026, on a Norfolk Southern plan to drop legacy cab signals on 14 line segments and rely on positive train control. -
Elimination Grant of $27.8 Million Reaches Scott Road in Allen County
Nov 09, 26 12:53 PM
Allen County received $27,878,116, also stated as $27.8 million, to design and build a grade separation where Scott Road crosses Norfolk Southern. -
Vermont Receives $60.3 Million for the Western Corridor
Nov 09, 26 12:45 PM
Vermont will receive $60.3 million to rehabilitate about 60 miles of the Western Corridor. The delegation quote also calls the sum $60 million. -
Burlingame Grade Separation Wins a Federal Grant
Nov 09, 26 10:42 AM
Rep. Kevin Mullin said on November 5, 2026 that the FRA awarded $90.4 million for the Caltrain Broadway grade separation in Burlingame. Early work is expected in May 2027. -
Orange County Rail Line Gets a Coastal Permit
Nov 09, 26 10:18 AM
The California Coastal Commission on November 5, 2026 approved a 10-year permit for the San Clemente rail line, including about 690,000 cubic yards of sand. -
Railroad Quiet Zones Are Reinstated in St. Louis
Nov 09, 26 10:14 AM
St. Louis said on November 6, 2026 that the FRA reinstated the city quiet zones. Horns are to stop after railroad systems are updated. -
Southern Pacific Railroad: Map, History, Logo
Nov 08, 26 01:58 PM
The Southern Pacific, from the December 2, 1865 charter and the Big Four to Sprint, the Rio Grande Industries purchase of 1988, and the Union Pacific merger of February 1, 1997. -
California Awards Flexible Rail Aid to Nine Projects
Nov 08, 26 01:15 PM
CalSTA on November 5, 2026 awarded $66.58 million in flexible State Rail Assistance to nine California projects. Each amount in the summary is a cap, printed as up to. -
CSX Leaves Three Days Out of the Weekly Reports
Nov 08, 26 12:02 PM
CSX told the Surface Transportation Board it cannot recover October 27-29 data for the EP 724 and EP 787 reports covering the week ending October 30, 2026. -
NJ Transit Advances Three Station Housing Projects
Nov 08, 26 11:56 AM
NJ Transit on November 5, 2026 advanced station projects in Jersey City, Bound Brook, and Morristown. The three are projected to add more than 1,000 homes. -
River Fox Train Wraps a Locomotive for America 250
Nov 08, 26 11:06 AM
The River Fox Train in West Sacramento wrapped a locomotive with America 250 markings, the American flag, and the Sacramento skyline. The wrap is expected to stay through 2027. -
California Keeps Metrolink Service in the 2027 Budget
Nov 07, 26 11:35 PM
Metrolink says a California State Transportation Agency grant lets the proposed fiscal year 2027 budget keep service at current levels. The board hearing is November 13, 2026. -
WM's 4-6-6-4 Locomotives (M-2): Specs, Roster, History
Nov 07, 26 04:37 PM
Western Maryland class M-2, twelve Baldwin 4-6-6-4s numbered 1201-1212, built in 1940 and 1941 for Hagerstown-Connellsville fast freight. Roster, specifications, and retirement in 1952-1953. -
Missouri Pacific Diesel Roster (All-Time)
Nov 07, 26 04:26 PM
Missouri Pacific diesel roster with builder serials, order numbers, subsidiary lettering, and renumberings. Alco, Baldwin, Electro-Motive, and General Electric. Texas and Pacific locomotives are on th… -
Missouri Pacific Steam Roster (Built Since 1900)
Nov 07, 26 04:21 PM
Missouri Pacific steam locomotives built since 1900. Drury quantity column 1,439. Sedalia rebuilds counted once, 1,407 frames. Last steam was 0-6-0 9301 in November 1955. -
Missouri Pacific Railroad: Map, Locomotives, Logo, History
Nov 07, 26 04:19 PM
The Missouri Pacific was a large Midwestern that carried a long history of financial difficulty until later years. -
LIRR Service Changes Start on November 9
Nov 07, 26 03:15 PM
New Long Island Rail Road schedules start on every branch on Monday, November 9, 2026. Midday and weekend times change. Rush hour does not. Babylon service returns in stages. -
Draft EA Reviews Norfolk Southern Track in London, Ohio
Nov 07, 26 11:35 AM
The Surface Transportation Board environmental office issued a draft assessment on November 6, 2026, for about 0.96 miles of Norfolk Southern track in London, Ohio. Comments are due November 20. -
Metrolink Lines Will Not Run on Three Routes November 7
Nov 07, 26 10:53 AM
Metrolink will not run the Ventura County, Orange County, or Inland Empire-Orange County lines on November 7 and 8, 2026. The advisory says no substitute transportation will be provided. -
Hartford Line Adds a Weekday Round Trip on November 16
Nov 07, 26 10:48 AM
Connecticut said the Hartford Line adds a weekday New Haven-Hartford round trip on November 16, starts a morning train in Springfield, and extends weekend stops to Windsor and Windsor Locks. -
Board Issues a Policy Statement on Rail Preemption
Nov 07, 26 10:44 AM
The Surface Transportation Board placed a policy statement on public inspection for the November 9 Federal Register. It reviews existing preemption precedent and says it makes no binding determination… -
NJ Transit Restores Lines After the Newark Drawbridge Stop
Nov 07, 26 10:37 AM
NJ Transit said Morris and Essex service between Hackettstown and Dover, and Montclair-Boonton service between Hackettstown and Montclair State University, resumed after the Newark Drawbridge stop. -
EMD "SD35" Locomotives: Data Sheet, Specs, Roster
Nov 06, 26 10:35 PM
EMD SD35, 2,500 horsepower, 16-cylinder 567D3A, built June 1964 through January 1966. 360 locomotives. Specifications and the production roster by owner, serial, and order. -
EMD "SDP35" Locomotives: Data Sheet, Specs, Roster
Nov 06, 26 10:32 PM
EMD SDP35, the steam-generator SD35. 35 locomotives, July 1964 through September 1965. Seaboard Air Line 1100-1119, Atlantic Coast Line 550, Louisville and Nashville 1700-1703, Union Pacific 1400-1409… -
RJ Corman Will Be Replaced on Part of the Luzerne Lines
Nov 06, 26 01:34 PM
A November 6, 2026 notice says Wilkes-Barre Terminal Railway would acquire about 59.65 miles in Luzerne County and replace R.J. Corman as operator on part of the line. The earliest date is November 22… -
NS Names a Student Hub at the University of Georgia
Nov 06, 26 12:03 PM
Norfolk Southern said a 100,000 dollar gift named a student-organization hub in Driftmier Engineering Center. The University of Georgia marked the naming on October 26. The space is for 23 clubs. -
Union Pacific Filed Its Vena Recording Certification
Nov 06, 26 11:56 AM
Union Pacific filed a November 5, 2026 verified statement that the confidential label is off the March 17 Vena recording and that parties of record received a copy at 3:30 p.m. Eastern. -
OmniTRAX Adds Tenants at Its Blue Island Hub
Nov 06, 26 10:26 AM
OmniTRAX has signed new construction-company leases at its 90-acre Blue Island, Illinois, hub and is planning a second phase. -
Veterans and Active-Duty Members Exceed 16 Percent of Norfolk Southern
Nov 06, 26 10:14 AM
Norfolk Southern said on November 5, 2026, that more than 3,000 veterans and active-duty service members are more than 16 percent of its workforce. This year grants are $100,000 and $50,000. -
BNSF: Merger Would Put Half of U.S. Rail Shipments Under One Railroad
Nov 06, 26 10:00 AM
BNSF chief marketing officer Tom G. Williams told customers on November 3, 2026, that a Union Pacific-Norfolk Southern merger would put about half of U.S. rail shipments under one railroad. Nothing is…
%2C%20was%20photographed%20here%20in%20Kansas%20City%2C%20Missouri%2C%20circa%201968.%20%20American-Rails.com%20collection.){kind=link}
