RL10
![]() | This article needs to be updated. The reason given is: Info on improvement projects is dated..(June 2020) |
![]() An RL10A-4 engine in London's Science Museum | |
Country of origin | United States of America |
---|---|
First flight | 1962 (RL10A-1) |
Manufacturer | Aerojet Rocketdyne |
Application | Upper stage engine |
Associated LV | Atlas Saturn I Titan IIIE Titan IV Delta III Delta IV DC-X Space Shuttle (canceled) Space Launch System (future) OmegA (canceled) Vulcan (future) |
Status | In production |
Liquid-fuel engine | |
Propellant | Liquid oxygen / liquid hydrogen |
Mixture ratio | 5.88:1 |
Cycle | Expander cycle |
Configuration | |
Nozzle ratio | 84:1 or 280:1 |
Performance | |
Thrust, vacuum | 110.1 kN (24,800 lbf) |
Specific impulse, vacuum | 465.5 seconds (4.565 km/s) |
Burn time | 700 seconds |
Dimensions | |
Length | 4.15 m (13.6 ft) w/ nozzle extended |
Diameter | 2.15 m (7 ft 1 in) |
Dry mass | 301 kg (664 lb) |
Used in | |
Centaur, DCSS, S-IV | |
References | |
References | [1] |
Notes | Performance values and dimensions are for RL10B-2. |
The RL10 is a liquid-fuel cryogenic rocket engine built in the United States by Aerojet Rocketdyne that burns cryogenic liquid hydrogen and liquid oxygen propellants. Modern versions produce up to 110 kN (24,729 lbf) of thrust per engine in vacuum. Three RL10 versions are in production for the Centaur upper stage of the Atlas V and the DCSS of the Delta IV. Three more versions are in development for the Exploration Upper Stage of the Space Launch System and the Centaur V of the Vulcan rocket.[2]
The expander cycle that the engine uses drives the turbopump with waste heat absorbed by the engine combustion chamber, throat, and nozzle. This, combined with the hydrogen fuel, leads to very high specific impulses (Isp) in the range of 373 to 470 s (3.66–4.61 km/s) in a vacuum. Mass ranges from 131 to 317 kg (289–699 lb) depending on the version of the engine.[3][4]
History
The RL10 was the first liquid hydrogen rocket engine to be built in the United States, with development of the engine by Marshall Space Flight Center and Pratt & Whitney beginning in the 1950s. The RL10 was originally developed as a throttleable engine for the USAF Lunex lunar lander, finally putting this capability to use twenty years later in the DC-X VTOL vehicle.[5]
The RL10 was first tested on the ground in 1959, at Pratt & Whitney's Florida Research and Development Center in West Palm Beach, Florida.[6][7] The first successful flight took place on November 27, 1963.[8][9] For that launch, two RL10A-3 engines powered the Centaur upper stage of an Atlas launch vehicle. The launch was used to conduct a heavily instrumented performance and structural integrity test of the vehicle.[10]
Multiple versions of the engine have been flown. The S-IV of the Saturn I used a cluster of six RL10A-3's, and the Titan program included RL10-based Centaur upper stages as well.[citation needed]
Four modified RL10A-5 engines were used in the McDonnell Douglas DC-X.[11]
A flaw in the brazing of an RL10B-2 combustion chamber was identified as the cause of failure for the 4 May 1999 Delta III launch carrying the Orion-3 communications satellite.[12]
The DIRECT version 3.0 proposal to replace Ares I and Ares V with a family of rockets sharing a common core stage recommended the RL10 for the second stage of the J-246 and J-247 launch vehicles.[13] Up to seven RL10 engines would have been used in the proposed Jupiter Upper Stage, serving an equivalent role to the Space Launch System Exploration Upper Stage.
Common Extensible Cryogenic Engine
![](http://upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Common_Extensible_Cryogenic_Engine.jpg/220px-Common_Extensible_Cryogenic_Engine.jpg)
In the early 2000s, NASA contracted with Pratt & Whitney Rocketdyne to develop the Common Extensible Cryogenic Engine (CECE) demonstrator. CECE was intended to lead to RL10 engines capable of deep throttling.[14] In 2007, its operability (with some "chugging") was demonstrated at 11:1 throttle ratios.[15] In 2009, NASA reported successfully throttling from 104 percent thrust to eight percent thrust, a record for an expander cycle engine of this type. Chugging was eliminated by injector and propellant feed system modifications that control the pressure, temperature and flow of propellants.[16] In 2010, the throttling range was expanded further to a 17.6:1 ratio, throttling from 104% to 5.9% power.[17]
Early 2010s possible successor
In 2012 NASA joined with the US Air Force (USAF) to study next-generation upper stage propulsion, formalizing the agencies' joint interests in a new upper stage engine to replace the Aerojet Rocketdyne RL10.
"We know the list price on an RL10. If you look at cost over time, a very large portion of the unit cost of the EELVs is attributable to the propulsion systems, and the RL10 is a very old engine, and there's a lot of craftwork associated with its manufacture. ... That's what this study will figure out, is it worthwhile to build an RL10 replacement?"
— Dale Thomas, Associated Director Technical, Marshall Space Flight Center[18]
From the study, NASA hoped to find a less expensive RL10-class engine for the upper stage of the Space Launch System (SLS).[18][19]
USAF hoped to replace the Rocketdyne RL10 engines used on the upper stages of the Lockheed Martin Atlas V and the Boeing Delta IV Evolved Expendable Launch Vehicles (EELV) that were the primary methods of putting US government satellites into space.[18] A related requirements study was conducted at the same time under the Affordable Upper Stage Engine Program (AUSEP).[19]
Improvements
The RL10 has evolved over the years. The RL10B-2 that was used on the DCSS had improved performance, an extendable nozzle, electro-mechanical gimbaling for reduced weight and increased reliability, and a specific impulse of 464 seconds (4.55 km/s).[citation needed]
As of 2016, Aerojet Rocketdyne was working toward incorporating additive manufacturing into the RL10 construction process. The company conducted full-scale, hot-fire tests on an engine with a printed main injector in March 2016,[20] and on an engine with a printed thrust chamber assembly in April 2017.[21]
Current applications for the RL10
- Atlas V Centaur (rocket stage): The single engine centaur (SEC) version uses the RL10C-1,[2] while the dual engine centaur (DEC) version retains the smaller RL10A-4-2.[22] An Atlas V mission (SBIRS-5) marked the first use of the RL10C-1-1 version. The mission was successful but observed unexpected vibration, and further use of the RL10C-1-1 model is on hold until the problem is better understood.[23]
- Delta Cryogenic Second Stage: The current DCSS has an RL10C-2-1 with an extensible nozzle.[2][24][25]
- Interim Cryogenic Propulsion Stage : The Interim Cryogenic Propulsion Stage or ICPS is used for the SLS and is similar to the DCSS, except that the engine is an RL10B-2 and it is adapted to fit on top of the 8.4 meter diameter core stage with four RS-25 Space Shuttle Main Engines.
Engines in development
- Exploration Upper Stage (EUS): EUS will initially use four RL10C-3 engines. When RL10C-X becomes available, the C-3 engines will be swapped out for C-X.[26]
- OmegA Upper Stage: In April 2018, Northrop Grumman Innovation Systems announced that two RL10C-5-1 engines would be used on OmegA in the upper stage.[27] Blue Origin's BE-3U and Airbus Safran's Vinci were also considered before Aerojet Rocketdyne's engine was selected. OmegA development was halted after it failed to win a National Security Space Launch contract.[28]
- Centaur V: On May 11, 2018, United Launch Alliance (ULA) announced that the RL10 upper stage engine had been selected for ULA's next-generation Vulcan Centaur rocket following a competitive procurement process.[29] Centaur V will normally use the RL10C-1-1,[2] but on Vulcan Centaur Heavy the RL10C-X will be used.[30]
Advanced Cryogenic Evolved Stage
As of 2009[update], an enhanced version of the RL10 was proposed to power the Advanced Cryogenic Evolved Stage (ACES), a long-duration, low-boiloff extension of existing ULA Centaur and Delta Cryogenic Second Stage (DCSS) technology for the Vulcan launch vehicle.[31] Long-duration ACES technology is intended to support geosynchronous, cislunar, and interplanetary missions. Another possible applications is as in-space propellant depots in LEO or at L2 that could be used as way-stations for other rockets to stop and refuel on the way to beyond-LEO or interplanetary missions. Cleanup of space debris was also proposed.[32]
Table of versions
Version | Status | First flight | Dry mass | Thrust | Isp (ve), vac. | Length | Diameter | T:W | O:F | Expansion ratio | Chamber pressure | Burn time | Associated stage | Notes |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
RL10A-1 | Retired | 1962 | 131 kg (289 lb) | 67 kN (15,000 lbf) | 425 s (4.17 km/s) | 1.73 m (5 ft 8 in) | 1.53 m (5 ft 0 in) | 52:1 | 5:1 | 40:1 | 430 s | Centaur A | Prototype [22][33][34] | |
RL10A-3C | Retired | 1963 | 131 kg (289 lb) | 65.6 kN (14,700 lbf) | 444 s (4.35 km/s) | 2.49 m (8 ft 2 in) | 1.53 m (5 ft 0 in) | 51:1 | 5:1 | 57:1 | 32.75 bar (3,275 kPa) | 470 s | Centaur B/C/D/E | [35] |
RL10A-3S | Retired | 1964 | 134 kg (296 lb) | 67 kN (15,000 lbf) | 427 s | 51:1 | 5:1 | 40:1 | Saturn I S-IV Stage | [8] | ||||
RL10A-4 | Retired | 1992 | 168 kg (370 lb) | 92.5 kN (20,800 lbf) | 449 s (4.40 km/s) | 2.29 m (7 ft 6 in) | 1.17 m (3 ft 10 in) | 56:1 | 5.5:1 | 84:1 | 392 s | Centaur IIA | [36] | |
RL10A-5 | Retired | 1993 | 143 kg (315 lb) | 64.7 kN (14,500 lbf) | 373 s (3.66 km/s) | 1.07 m (3 ft 6 in) | 1.02 m (3 ft 4 in) | 46:1 | 6:1 | 4:1 | 127 s | DC-X | [37] | |
RL10B-2 | Active | 1998 | 277 kg (611 lb) | 110.1 kN (24,800 lbf) | 465.5 s (4.565 km/s) | 4.15 m (13.6 ft) | 2.15 m (7 ft 1 in) | 40:1 | 5.88:1 | 280:1 | 44.12 bar (4,412 kPa) | 5-m: 1,125 s 4-m: 700 s |
Delta Cryogenic Second Stage, Interim Cyrogenic Propulsion Stage |
[1][38] |
RL10A-4-1 | Retired | 2000 | 167 kg (368 lb) | 99.1 kN (22,300 lbf) | 451 s (4.42 km/s) | 1.53 m (5 ft 0 in) | 61:1 | 84:1 | 740 s | Centaur IIIA | [39] | |||
RL10A-4-2 | Retired | 2002 | 168 kg (370 lb) | 99.1 kN (22,300 lbf) | 451 s (4.42 km/s) | 1.17 m (3 ft 10 in) | 61:1 | 84:1 | 740 s | Centaur IIIB Centaur SEC Centaur DEC |
[40][41] | |||
RL10B-X | Cancelled | 317 kg (699 lb) | 93.4 kN (21,000 lbf) | 470 s (4.6 km/s) | 1.53 m (5 ft 0 in) | 30:1 | 250:1 | 408 s | Centaur B-X | [42] | ||||
CECE | Demonstrator project | 160 kg (350 lb) | 67 kN (15,000 lbf), throttle to 5–10% | >445 s (4.36 km/s) | 1.53 m (5 ft 0 in) | 43:1 | [43][44] | |||||||
RL10C-1 | Active | 2014 | 190 kg (420 lb) | 101.8 kN (22,890 lbf) | 449.7 s (4.410 km/s) | 2.12 m (6 ft 11 in) | 1.45 m (4 ft 9 in) | 57:1 | 5.88:1 | 130:1 | Centaur SEC Centaur DEC |
[45][46][47][41] | ||
RL10C-1-1 | Active | 2021 | 188 kg (415 lb) | 106 kN (23,825 lbF) | 453.8 s | 2.46 m (8 ft 0.7 in) | 1.57 m (4 ft 9 in) | 57:1 | 5.5:1 | Centaur V | [2] | |||
RL10C-2-1 | Active | 301 kg (664 lb) | 109.9 kN (24,750 lbF) | 465.5 s | 4.15 m (13 ft 8 in) | 2.15 m (7 ft 1 in) | 37:1 | 5.88:1 | 280:1 | Delta Cryogenic Second Stage | [48] | |||
RL10C-3 | In development | 2026 | 230 kg (508 lb) | 108 kN (24,340 lbF) | 460.1 s | 3.15 m (10 ft 4.3 in) | 1.85 m (6 ft 1 in) | 48:1 | 5.7:1 | Exploration Upper Stage | [2] | |||
RL10C-5-1 | Cancelled (2020) | — | 188 kg (415 lb) | 106 kN (23,825 lbF) | 453.8 s | 2.46 m (8 ft 0.7 in) | 1.57 m (4 ft 9 in) | 57:1 | 5.5:1 | OmegA | [2][28] | |||
RL10C-X | In development | 106 kN (24,000 lbF) | 461 s | Vulcan Centaur | 3D Printed [49] |
Partial specifications
![](http://upload.wikimedia.org/wikipedia/commons/thumb/9/95/RL-10_rocket_engine.jpg/300px-RL-10_rocket_engine.jpg)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/2/22/Rl-10engine.jpg/220px-Rl-10engine.jpg)
All versions
- Contractor: Pratt & Whitney
- Propellants: liquid oxygen, liquid hydrogen[50]
- Design: expander cycle[51]
RL10A
- Thrust (altitude): 15,000 lbf (66.7 kN)[33]
- Specific impulse: 433 seconds (4.25 km/s)
- Engine weight, dry: 298 lb (135 kg)
- Height: 68 in (1.73 m)
- Diameter: 39 in (0.99 m)
- Nozzle expansion ratio: 40 to 1
- Propellant flow: 35 lb/s (16 kg/s)
- Vehicle application: Saturn I, S-IV 2nd stage, 6 engines
- Vehicle application: Centaur upper stage, 2 engines
RL10B-2
![](http://upload.wikimedia.org/wikipedia/commons/thumb/5/50/Second_stage_of_a_Delta_IV_Medium_rocket.jpg/220px-Second_stage_of_a_Delta_IV_Medium_rocket.jpg)
- Thrust (altitude): 24,750 lbf (110.1 kN)[50]
- Specific impulse: 465.5 seconds (4.565 km/s)[50]
- Engine weight, dry: 664 lb (301.2 kg)[50]
- Height: 163.5 in (4.14 m)[50]
- Diameter: 84.5 in (2.21 m)[50]
- Expansion ratio: 280 to 1
- Mixture ratio: 5.88 to 1 oxygen:hydrogen mass ratio[50]
- Propellant flow: fuel, 7.72 lb/s (3.5 kg/s); oxidizer 45.42 lb/s (20.6 kg/s)[50]
- Vehicle application: Delta III, Delta IV second stage (1 engine)
Engines on display
- An RL10A-1 is on display at the New England Air Museum, Windsor Locks, Connecticut[52]
- An RL10 is on display at the Museum of Science and Industry, Chicago, Illinois[53]
- An RL10 is on display at the U.S. Space & Rocket Center, Huntsville, Alabama[53]
- An RL10 is on display at Southern University, Baton Rouge, Louisiana[54]
- Two RL10 engines are on display at US Space Walk of Fame, Titusville, Florida[55]
- An RL10 is on display at the Cox Science Center and Aquarium, West Palm Beach, Florida.
- An RL10 is on display in the Aerospace Engineering Department, Davis Hall at Auburn University.[citation needed]
- An RL10A-4 is on display at the Science Museum in London, UK.
- An RL10 is on display at the Museum of Life and Science in Durham, NC
- An RL10 is on display at the San Diego Air & Space Museum in San Diego, CA.
See also
- Spacecraft propulsion
- RL60
- MARC-60
- RD-0146
- XCOR/ULA aluminum alloy nozzle engine, under development in 2011
References
- ^ a b Wade, Mark (November 17, 2011). "RL-10B-2". Encyclopedia Astronautica. Archived from the original on February 4, 2012. Retrieved February 27, 2012.
- ^ a b c d e f g "Aerojet Rocketdyne RL10 Propulsion System" (PDF). Aerojet Rocketdyne. March 2019.
- ^ "RL-10C". www.astronautix.com. Archived from the original on December 28, 2016. Retrieved April 6, 2020.
- ^ "RL-10A-1". www.astronautix.com. Archived from the original on December 28, 2016. Retrieved April 6, 2020.
- ^ Wade, Mark. "Encyclopedia Astronautica—Lunex Project page". Encyclopedia Astronautica. Archived from the original on August 31, 2006.
- ^ Connors, p 319
- ^ "Centaur". Gunter's Space Pages.
- ^ a b Sutton, George (2005). History of liquid propellant rocket engines. American Institute of Aeronautics and Astronautics. ISBN 1-56347-649-5.
- ^ "Renowned Rocket Engine Celebrates 40 Years of Flight". Pratt & Whitney. November 24, 2003. Archived from the original on June 14, 2011.
- ^ "Atlas Centaur 2". National Space Science Data Center. NASA.
- ^ Wade, Mark. "DCX". Encyclopedia Astronautica. Archived from the original on December 28, 2012. Retrieved January 4, 2013.
- ^ "Delta 269 (Delta III) Investigation Report" (PDF). Boeing. August 16, 2000. MDC 99H0047A. Archived from the original (PDF) on June 16, 2001.
- ^ "Jupiter Launch Vehicle – Technical Performance Summaries". Archived from the original on June 8, 2009. Retrieved July 18, 2009.
- ^ "Common Extensible Cryogenic Engine (CECE)". United Technologies Corporation. Archived from the original on March 4, 2012.
- ^ "Throttling Back to the Moon". NASA. July 16, 2007. Archived from the original on April 2, 2010.
- ^ "NASA Tests Engine Technology for Landing Astronauts on the Moon". NASA. January 14, 2009.
- ^ Giuliano, Victor (July 25, 2010). "CECE: Expanding the Envelope of Deep Throttling Technology in Liquid Oxygen/Liquid Hydrogen Rocket Engines for NASA Exploration Missions" (PDF). NASA Technical Reports Server.
- ^ a b c Roseberg, Zach (April 12, 2012). "NASA, US Air Force to study joint rocket engine". Flight Global. Retrieved June 1, 2012.
- ^ a b Newton, Kimberly (April 12, 2012). "NASA Partners With U.S. Air Force to Study Common Rocket Propulsion Challenges". NASA.
- ^ "Aerojet Rocketdyne Successfully Tests Complex 3-D Printed Injector in World's Most Reliable Upper Stage Rocket Engine" (Press release). Aerojet Rocketdyne. March 7, 2016. Retrieved April 20, 2017.
- ^ "Aerojet Rocketdyne Achieves 3-D Printing Milestone with Successful Testing of Full-Scale RL10 Copper Thrust Chamber Assembly" (Press release). Aerojet Rocketdyne. April 3, 2017. Retrieved April 11, 2017.
- ^ a b Wade, Mark (November 17, 2011). "RL-10A-1". Encyclopedia Astronautica. Archived from the original on November 15, 2011. Retrieved February 27, 2012.
- ^ "ULA delays further use of enhanced upper-stage engine pending studies".
- ^ "ULA Vulcan Launch Vehicle (as announced/built) - General Discussion Thread 3". forum.nasaspaceflight.com. Retrieved June 6, 2020.
- ^ "Delta IV Data Sheet". www.spacelaunchreport.com. Retrieved June 6, 2020.
- ^ Sloss, Philip (March 4, 2021). "NASA, Boeing looking to begin SLS Exploration Upper Stage manufacturing in 2021". NASASpaceflight. Retrieved October 15, 2021.
- ^ "RL-10 Selected for OmegA Rocket". Aerojet Rocketdyne. April 16, 2018. Retrieved May 14, 2018.
- ^ a b "Northrop Grumman to terminate OmegA rocket program". SpaceNews. September 9, 2020. Retrieved November 23, 2020.
- ^ "United Launch Alliance Selects Aerojet Rocketdyne's RL10 Engine". ULA. May 11, 2018. Retrieved May 13, 2018.
- ^ "Vulcan Cutaway Poster" (PDF). United Launch Alliance. Retrieved October 15, 2021.
- ^ Kutter, Bernard F.; Zegler, Frank; Barr, Jon; Bulk, Tim; Pitchford, Brian (2009). "Robust Lunar Exploration Using an Efficient Lunar Lander Derived from Existing Upper Stages" (PDF). AIAA.
- ^ Zegler, Frank; Bernard Kutter (September 2, 2010). "Evolving to a Depot-Based Space Transportation Architecture" (PDF). AIAA SPACE 2010 Conference & Exposition. AIAA. Archived from the original (PDF) on October 20, 2011. Retrieved January 25, 2011.
ACES design conceptualization has been underway at ULA for many years. It leverages design features of both the Centaur and Delta Cryogenic Second Stage (DCSS) upper stages and intends to supplement and perhaps replace these stages in the future. ...
- ^ a b Bilstein, Roger E. (1996). "Unconventional Cryogenics: RL-10 and J-2". Stages to Saturn; A Technological History of the Apollo/Saturn Launch Vehicles. Washington, D.C.: NASA History Office. Retrieved December 2, 2011.
- ^ "Atlas Centaur". Gunter's Space Page. Retrieved February 29, 2012.
- ^ Wade, Mark (November 17, 2011). "RL-10A-3". Encyclopedia Astronautica. Archived from the original on December 6, 2011. Retrieved February 27, 2012.
- ^ Wade, Mark (November 17, 2011). "RL-10A-4". Encyclopedia Astronautica. Archived from the original on November 15, 2011. Retrieved February 27, 2012.
- ^ Wade, Mark (November 17, 2011). "RL-10A-5". Encyclopedia Astronautica. Archived from the original on November 15, 2011. Retrieved February 27, 2012.
- ^ "Delta IV Launch Services User's Guide, June 2013" (PDF). ULA Launch. Retrieved March 15, 2018.
- ^ Wade, Mark (November 17, 2011). "RL-10A-4-1". Encyclopedia Astronautica. Archived from the original on November 17, 2011. Retrieved February 27, 2012.
- ^ Wade, Mark (November 17, 2011). "RL-10A-4-2". Encyclopedia Astronautica. Archived from the original on January 30, 2012. Retrieved February 27, 2012.
- ^ a b "RL10 Engine". Aerojet Rocketdyne.
- ^ Wade, Mark (November 17, 2011). "RL-10B-X". Encyclopedia Astronautica. Archived from the original on November 15, 2011. Retrieved February 27, 2012.
- ^ "Commons Extensible Cryogenic Engine". Pratt & Whitney Rocketdyne. Archived from the original on March 4, 2012. Retrieved February 28, 2012.
- ^ "Common Extensible Cryogenic Engine - Aerojet Rocketdyne". www.rocket.com. Retrieved April 8, 2018.
- ^ "Cryogenic Propulsion Stage" (PDF). NASA. Retrieved October 11, 2014.
- ^ "Atlas-V with RL10C powered Centaur". forum.nasaspaceflight.com. Retrieved April 8, 2018.
- ^ "Evolution of Pratt & Whitney's cryogenic rocket engine RL-10". Archived from the original on March 3, 2016. Retrieved February 20, 2016.
- ^ "RL10 Engine | Aerojet Rocketdyne". www.rocket.com. Retrieved June 19, 2020.
- ^ "Aerojet Rocketdyne Secures Its Largest RL10 Engine Contract From ULA". www.aerojetrocketdyne.com. Retrieved April 16, 2022.
- ^ a b c d e f g h "RL10B-2" (PDF). Pratt & Whitney Rocketdyne. 2009. Archived from the original (PDF) on March 26, 2012. Retrieved January 29, 2012.
- ^ Sutton, A. M.; Peery, S. D.; Minick, A. B. (January 1998). "50K expander cycle engine demonstration". AIP Conference Proceedings. 420: 1062–1065. doi:10.1063/1.54719.
- ^ "Pratt & Whitney RL10A-1 Rocket Engine". New England Air Museum. Retrieved April 26, 2014.
- ^ a b "Photos of Rocket Engines". Historic Spacecraft. Retrieved April 26, 2014.
- ^ Colaguori, Nancy; Kidder, Bryan (November 3, 2006). "Pratt & Whitney Rocketdyne Donates Model of Legendary Rl10 Rocket Engine to Southern University" (Press release). Pratt & Whitney Rocketdyne. PR Newswire. Retrieved April 26, 2014.
- ^ "American Space Museum & Space Walk of Fame". www.facebook.com. Archived from the original on February 26, 2022. Retrieved April 8, 2018.
Bibliography
- Connors, Jack (2010). The Engines of Pratt & Whitney: A Technical History. Reston. Virginia: American Institute of Aeronautics and Astronautics. ISBN 978-1-60086-711-8.
External links
![](http://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png)