Allison Engine Company
| Company type | Subsidiary (formerly) |
|---|---|
| Industry | Aerospace, aircraft engines |
| Founded | September 1904 |
| Founder | James A. Allison, Percy C. "Fred" Avery, Carl G. Fisher |
| Fate | Acquired by Rolls-Royce plc in 1995; became Rolls-Royce North America |
| Headquarters | Indianapolis, Indiana , United States |
Key people | James A. Allison (founder), Norman H. Gillman (chief engineer) |
| Products | Aircraft engines, bearings, drive shafts, gear chains |
| Parent | General Motors (until 1995), Rolls-Royce plc (from 1995) |
The Allison Engine Company was a prominent American manufacturer specializing in aircraft engine production. Shortly after the passing of its founder, James A. Allison, in 1929, ownership transferred to the Fisher brothers, who subsequently sold the company to General Motors. GM retained control of Allison for the majority of its existence until 1995, when it was acquired by Rolls-Royce plc and became part of its US operations under the name Rolls-Royce North America.
History
An antecedent to the Allison Engine Company, known as the Concentrated Acetylene Company, was established in September 1904 by James Allison, Percy C. "Fred" Avery, and Carl G. Fisher. Avery held the patent for acetylene-based headlights, which were later manufactured by the Prest-O-Lite Company. Following an explosion at their Indianapolis facility, the business relocated near the racing circuit in Speedway, Indiana, where both Allison and Fisher managed race car teams. Allison constructed a workshop at Speedway to service his vehicles, which became known as Allison Plant #1. Eventually, Fisher and Allison sold their Prest-O-Lite interests to Union Carbide for $9 million.
Allison Speedway Team Company
The origins of Allison were rooted in engine and automobile "hot rodding" services tailored to the Indianapolis Motor Speedway. Initially called the Indianapolis Speedway Team Company, it underwent multiple name changes—including Allison Speedway Team Company, Allison Experimental Company, and Allison Engineering Company—before being absorbed as a division within General Motors.
A core product of the company was a patented steel-backed bronze bearing designed for high-performance engines. This bearing achieved widespread use in engines produced by Pratt & Whitney, Wright, Rolls-Royce, among others, positioning Allison as a key player in bearing manufacturing. The company also pioneered an ultraviolet detection technique for identifying defective bearings, which garnered commendation from the U.S. Army.
Moreover, Allison supplied drive shafts, extensions, and gear chains tailored for high-output engines upon request. The company's principal focus evolved into upgrading older Liberty engines into enhanced versions suitable for aircraft and marine uses.
To better support its racing ventures, Allison relocated on January 1, 1917, into a facility situated at what would later become the Indianapolis Motor Speedway. During this period, engineer Norman H. Gillman was recruited from a rival team to serve as chief engineer.
Allison's move to Florida
Following World War I, Allison relocated to Florida to pursue real estate ventures, leaving Gillman responsible for company operations. To maintain the firm’s standing, Allison assigned Gillman to develop a V-12 marine engine inspired by insights gained from the Liberty engine.
In 1927, ownership of Allison's company transferred to Captain Eddie Rickenbacker for $700,000. After James Allison's death in 1929, the Fisher brothers acquired the business and subsequently sold it to General Motors, which retained ownership throughout most of its history. In 1995, Rolls-Royce plc purchased the Allison Engine Company and incorporated it as its US subsidiary under the name Rolls-Royce Corporation.
Hyper engine
During the late 1920s, the United States Army sponsored the development of high-performance engines through its hyper engine initiative, aiming for production by Continental Motors. Independently, Allison's manager Norman Gilman designed a high-output cylinder, which led to the creation of the X-4520—a 24-cylinder, air-cooled engine arranged in an “X” configuration, built in 1925. Although presented to the Army in 1928, the project was ultimately rejected.
General Motors
Following James Allison's passing in 1929, the Fisher brothers took control of the company and pursued development of a six-cylinder "family aircraft" engine based on Gilman’s cylinder design. However, before significant advancement occurred, Fisher sold Allison to General Motors. Due to financial difficulties during the Great Depression, GM discontinued development efforts. Gilman persisted with a conceptual V-12 engine project; while initially dismissed by the Army, it attracted some interest from the United States Navy for use in airships. This support ceased after the 1935 USS Macon crash, which ended the need for such an engine.
V-1710
The initial V-1710 engine, serial number 1, was acquired by the U.S. Navy under the designation GV-1710-2. The USAAC obtained the second engine, named XV-1710-1, followed by additional units for Navy airships and a batch of eleven Air Corps engines funded in fiscal year 1934. Production quickly scaled up, eventually surpassing 70,000 units.
As Army interest grew, Allison was tasked with developing the "C" model. With limited financial support from the Army, Allison largely funded this development internally. The V-1710-C made its maiden flight on December 14, 1936, and by April 1937 had successfully completed the Army’s 150-hour Type Test at 1,000 horsepower—the first engine to achieve this milestone. After other projects were discontinued, the V-1710 became the key powerplant for USAAC fighters such as the P-38 Lightning, P-39 Airacobra, and P-40 Warhawk.
The Army preferred exhaust-driven turbochargers over mechanically driven superchargers to maximize energy efficiency from exhaust gases. As a result, limited effort was invested in equipping the V-1710 with complex two-stage superchargers. This design choice impacted performance in aircraft like the P-39 and P-40 that lacked space for turbochargers and thus experienced diminished capabilities at high altitudes. This shortcoming eventually led to replacing the V-1710 with the Rolls-Royce Merlin engine in the P-51 Mustang.
Post-war
Following World War II, as demand for the V-1710 declined, Allison redirected its manufacturing capacity toward producing jet engines under license from General Electric, beginning with GE’s I-40 model rebranded as the Allison J33. By 1955, production had exceeded 7,000 J33 engines.
Allison also manufactured GE’s axial flow engine design as the Allison J35, which powered aircraft including the F-84 Thunderjet and F-89 Scorpion. Production concluded in 1955 after more than 14,000 units were delivered.
For U.S. Navy applications, Allison developed turboprop engines such as the Allison T38 and its paired variant, the Allison T40. The T40 program was canceled due to mechanical complexity issues. Subsequently, Allison created the successful Allison T56, an enlarged version of the T38 that powered aircraft like the C-130 Hercules. Engines based on the T56 also converted Convair propeller airliners into turboprops—most notably producing the widely operated Convair 580, used by regional carriers including Allegheny Airlines, original Frontier Airlines, as well as major airlines like American Airlines, Eastern Airlines, United Airlines, and Pan-Am.
Expanding on the T56 platform, Allison developed a series of engines culminating in models such as the T406/Allison AE1107 turboshaft for the V-22 Osprey, the Allison AE2100 turboprop powering newer C-130 variants, and the Allison/Rolls-Royce AE 3007 turbofan utilized in regional jets like Embraer’s ERJ series widely adopted in commercial aviation.
One of Allison’s most enduring product lines is the Allison Model 250 turboshaft/turboprop family introduced in the early 1960s amid helicopters transitioning from piston to turbine powerplants. These engines powered helicopters including Bell’s JetRanger and LongRanger models as well as early versions of the Sikorsky S-76.
Experimental Developments
During the mid-1970s, the Allison Division of General Motors in Detroit incorporated ceramic parts into the Allison GT 404-4 turboshaft engine designed for truck applications. Allison, in collaboration with GM, further advanced ceramic turbine engine technology through the early 1990s, successfully creating reliable automotive engines that could operate on a variety of fuels such as gasoline, diesel, kerosene, alcohol, vegetable oil, and coal powder.
In the 1980s, Allison joined forces with Pratt & Whitney to showcase the 578-DX propfan engine. This model differed from its competitor, the General Electric GE-36 UDF, by including a reduction gearbox connecting the low-pressure turbine to the propfan blades. Despite this innovation, concerns about noise levels and a substantial decline in aviation fuel prices prompted NASA to terminate the program.
By 1995, Allison had tested a prototype lift fan intended for the Joint Strike Fighter Program. Two years later, in 1997, a full prototype was demonstrated by Allison Advanced Development Company—an entity owned by Rolls-Royce but operated under American control—with LiftFan nozzle evaluations conducted at NASA’s Lewis Research Center.
Use in Automobiles
In 1965, drag racer Jim Lytle created Quad Al, a vehicle powered by four surplus World War II V-12 Allison aero engines arranged in a four-wheel-drive configuration, delivering roughly 12,000 horsepower. Although the engines were operational, the car never ran due to prohibitively expensive custom gearboxes and clutches required to manage the immense torque generated. The vehicle remains stored in Indiana without its engines.
Rolls-Royce Acquisition
General Motors decided to divest Allison in 1992 to concentrate on regaining market share in the automobile sector. Rolls-Royce made an acquisition attempt in 1993; however, GM chose a management buyout valued at $370 million instead.
In 1995, U.S. regulatory authorities approved Rolls-Royce’s acquisition of Allison for $525 million with certain limitations concerning the Joint Strike Fighter Program. These restrictions were relaxed by 2000. Subsequently, in 2001, the U.S. government selected the F-35 aircraft incorporating Rolls-Royce’s LiftFan alongside Pratt & Whitney’s F135 engines. Additionally, Allison collaborated with General Electric and Rolls-Royce on the F136 Fighter Engine Team.
Product Line
| Model name | Configuration | Power |
|---|---|---|
| Allison V-1710 | V12 | 1,100 hp |
| Allison V-3420 | W24 | 2,100 hp |
| Allison J33 | Turbojet | 3,900 lbf |
| Allison J35 | Turbojet | 5,600 lbf |
| Allison J71 | Turbojet | 10,000 lbf |
| Allison J102 | Turbojet | |
| Allison TF41 | Turbofan | 14,250 lbf |
| General Electric/Allison/Rolls-Royce F136 | Turbofan | 28,000 lbf |
| Allison AE 3007 | Turbofan | 7,580 to 9,500 lbf |
| Allison 250/T63 | Turboshaft | 317 hp |
| Allison AE 2100 | Turboprop | 4,637 hp |
| Allison T38 | Turboprop | 2,550 hp |
| Allison T40 | Turboprop | 5,100 hp |
| Allison T56 | Turboprop | 5,912 hp |
Bibliography
External links
| Model name | Configuration | Power |
|---|---|---|
| Allison T61 | Turboprop | 6,500 hp |
| Allison T71 | ||
| Allison T78 | Turboprop | 4,000 hp |
| Allison T80 | ||
| Allison T406 | Turboshaft | 6,150 hp |
| Allison T701 | Turboshaft | 8,079 hp |
| Pratt & Whitney/Allison 578-DX
| align=center | Propfan | align=center | 22,000 lbf |