General Electric YJ93: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous edit
Content deleted Content added
VisualWikitext
Monkbot (talk | contribs)
Bots
3,119,769 edits
m Task 18 (cosmetic): eval 5 templates: hyphenate params (3×);
No edit summary
 
(6 intermediate revisions by 4 users not shown)
Line 1: Line 1:
{{Short description|Turbojet engine}}
<!-- This article is a part of [[Wikipedia:WikiProject Aircraft]]. Please see [[Wikipedia:WikiProject Aircraft/page content]] for recommended layout. -->
<!-- This article is a part of [[Wikipedia:WikiProject Aircraft]]. Please see [[Wikipedia:WikiProject Aircraft/page content]] for recommended layout. -->
{|{{Infobox Aircraft Begin
{|{{Infobox Aircraft Begin
Line 25: Line 26:
==Design and development==
==Design and development==


The YJ93 started life as the General Electric X275, an enlarged version of the [[General Electric J79]] turbojet. This evolved to the X279 when [[Mach number|Mach]] 3 cruise became a requirement, and ultimately became the YJ93.<ref>Jenkins, Dennis R. and Tony R. Landis. ''Valkyrie: North American's Mach 3 Superbomber''. North Branch, Minnesota: Specialty Press, 2005. {{ISBN|1-58007-072-8}}.
The YJ93 started life as the General Electric J79-X275, an enlarged version of the [[General Electric J79]] turbojet with "275" meaning Mach 2.75, the engine's target operating speed.<ref name=eightdecades>{{cite book |title=Eight Decades of Progress : A Heritage of Aircraft Turbine Technology |date=1990 |publisher=GE Aircraft Engines |pages=117 |lccn=90082948}}</ref> This design evolved into the X279 when [[Mach number|Mach]] 3 cruise became a requirement, and ultimately became the YJ93.<ref>Jenkins, Dennis R. and Tony R. Landis. ''Valkyrie: North American's Mach 3 Superbomber''. North Branch, Minnesota: Specialty Press, 2005. {{ISBN|1-58007-072-8}}.
</ref>
</ref>


The engine used a special high-temperature [[JP-6]] fuel. The six YJ93 engines in the XB-70 Valkyrie were capable of producing a thrust to weight ratio of 5:1 allowing for a speed of {{convert|2000|mph|km/h|abbr=on}} (approximately Mach 3) at an altitude of {{convert|70000|ft}}.<ref>[http://www.nationalmuseum.af.mil/Visit/MuseumExhibits/FactSheets/Display/tabid/509/Article/195701/general-electric-yj93-g-3-turbojet.aspx National Museum of the USAF] Retrieved: December 21, 2016</ref>
The engine used a special high-temperature [[JP-6]] fuel. The six YJ93 engines in the XB-70 Valkyrie were capable of producing a thrust to weight ratio of 5:1 allowing for a speed of {{convert|2000|mph|km/h|abbr=on}} (approximately Mach 3) at an altitude of {{convert|70000|ft}}.<ref>[http://www.nationalmuseum.af.mil/Visit/MuseumExhibits/FactSheets/Display/tabid/509/Article/195701/general-electric-yj93-g-3-turbojet.aspx National Museum of the USAF] Retrieved: December 21, 2016</ref> The first engine went on test in September 1958 and featured advanced technology achievements such as electrolytically drilling longitudinal air cooling holes in the turbine blades.<ref name=eightdecades/>


The XF-108 interceptor was cancelled outright and the B-70 project was re-oriented to a research project only.<ref>[http://home.att.net/~jbaugher2/b58_9.html NB-58A Testbed for General Electric J93<!-- Bot generated title -->] {{webarchive|url=https://web.archive.org/web/20080724113441/http://home.att.net/~jbaugher2/b58_9.html |date=2008-07-24 }}</ref>
The XF-108 interceptor was cancelled outright, and the B-70 project was re-oriented to a research project only.<ref>[http://home.att.net/~jbaugher2/b58_9.html NB-58A Testbed for General Electric J93<!-- Bot generated title -->] {{webarchive|url=https://web.archive.org/web/20080724113441/http://home.att.net/~jbaugher2/b58_9.html |date=2008-07-24 }}</ref>


==Variants==
==Variants==
;J93-GE-1: {{convert|24800|lbf|kN|abbr=on}} thrust with afterburner.<ref>{{cite web |title=Characteristics Summary: F-108A |url=http://www.alternatewars.com/SAC/F-108_Rapier_CS_-_2_May_1958.pdf |publisher=US Air Force |access-date=15 December 2018 |date=2 May 1958}}</ref>
;J93-GE-1: {{convert|24800|lbf|kN|abbr=on}} thrust with afterburner.<ref>{{cite web |title=Characteristics Summary: F-108A |url=http://www.alternatewars.com/SAC/F-108_Rapier_CS_-_2_May_1958.pdf |publisher=US Air Force |access-date=15 December 2018 |date=2 May 1958}}</ref>
;J93-GE-3: Production variant produced in small numbers for the [[North American XB-70 Valkyrie]] programme.
;J93-GE-3: Production variant produced in small numbers for the [[North American XB-70 Valkyrie]] program.
;J93-GE-3R: Variant with thrust reverser, {{convert|27200|lbf|kN|abbr=on}} thrust with afterburner.<ref>{{cite web |title=Characteristics Summary: F-108A |url=http://www.alternatewars.com/SAC/F-108A_Rapier_CS_-_15_December_1958.pdf |publisher=US Air Force |access-date=15 December 2018|date=15 December 1958}}</ref>
;J93-GE-3R: Variant with thrust reverser, {{convert|27200|lbf|kN|abbr=on}} thrust with afterburner.<ref>{{cite web |title=Characteristics Summary: F-108A |url=http://www.alternatewars.com/SAC/F-108A_Rapier_CS_-_15_December_1958.pdf |publisher=US Air Force |access-date=15 December 2018|date=15 December 1958}}</ref>
;J93-GE-3AR: Variant intended for the [[North American XF-108 Rapier]].
;J93-GE-3AR: Variant intended for the [[North American XF-108 Rapier]].
Line 45: Line 46:
==Specifications (J93-GE-3)==
==Specifications (J93-GE-3)==
{{jetspecs
{{jetspecs
|ref=Aircraft engines of the World 1966/77,<ref name=AEotW66-67>{{cite book |last=Wilkinson |first=Paul H. |title=Aircraft engines of the World 1966/77 |year=1966 |publisher=Sir Isaac Pitman & Sons Ltd. |location=London |edition=21st|page=83}}</ref> Military Turbojet/Turbofan Specifications,<ref name="turbo">{{cite web|title=Military Turbojet/Turbofan Specifications|url=http://www.jet-engine.net/miltfspec.html|website=www.jet-engine.net|access-date=31 December 2017}}</ref> North American XB-70A Valkyrie<ref name="Jenkins_Landis">{{cite book|last1=Jenkins|first1=Dennis R.|last2=Landis|first2=Tony|title=North American XB-70A Valkyrie|date=2002|publisher=Specialty Press Publishers and Wholesalers|location=North Branch [USA]|isbn=1-58007-056-6}}</ref>
|ref=Aircraft engines of the World 1966/77,<ref name=AEotW66-67>{{cite book |last=Wilkinson |first=Paul H. |title=Aircraft engines of the World 1966/77 |year=1966 |publisher=Sir Isaac Pitman & Sons Ltd. |location=London |edition=21st|page=83}}</ref> Military Turbojet/Turbofan Specifications,<ref name="turbo">{{cite web|title=Military Turbojet/Turbofan Specifications|url=http://www.jet-engine.net/miltfspec.html|website=www.jet-engine.net|access-date=31 December 2017|archive-date=2 October 2011|archive-url=https://web.archive.org/web/20111002090707/http://www.jet-engine.net/miltfspec.html|url-status=dead}}</ref> North American XB-70A Valkyrie<ref name="Jenkins_Landis">{{cite book|last1=Jenkins|first1=Dennis R.|last2=Landis|first2=Tony|title=North American XB-70A Valkyrie|date=2002|publisher=Specialty Press Publishers and Wholesalers|location=North Branch [USA]|isbn=1-58007-056-6}}</ref>
|type=[[Turbojet]] with afterburner
|type=[[Turbojet]] with afterburner
|length={{cvt|237|in}}
|length={{cvt|237|in}}

Latest revision as of 17:12, 16 January 2024

YJ93
YJ93-GE-3 engine at National Museum of the United States Air Force
Type Turbojet
National origin United States
Manufacturer General Electric Aircraft Engines
Major applications North American XB-70 Valkyrie
Developed into General Electric GE4
YB-58 at Edwards AFB with GE J93 engine pod

The General Electric YJ93 turbojet engine was designed as the powerplant for both the North American XB-70 Valkyrie bomber and the North American XF-108 Rapier interceptor. The YJ93 was a single-shaft axial-flow turbojet with a variable-stator compressor and a fully variable convergent/divergent exhaust nozzle. The maximum sea-level thrust was 28,800 lbf (128 kN).[1]

Design and development[edit]

The YJ93 started life as the General Electric J79-X275, an enlarged version of the General Electric J79 turbojet with "275" meaning Mach 2.75, the engine's target operating speed.[2] This design evolved into the X279 when Mach 3 cruise became a requirement, and ultimately became the YJ93.[3]

The engine used a special high-temperature JP-6 fuel. The six YJ93 engines in the XB-70 Valkyrie were capable of producing a thrust to weight ratio of 5:1 allowing for a speed of 2,000 mph (3,200 km/h) (approximately Mach 3) at an altitude of 70,000 feet (21,000 m).[4] The first engine went on test in September 1958 and featured advanced technology achievements such as electrolytically drilling longitudinal air cooling holes in the turbine blades.[2]

The XF-108 interceptor was cancelled outright, and the B-70 project was re-oriented to a research project only.[5]

Variants[edit]

J93-GE-1
24,800 lbf (110 kN) thrust with afterburner.[6]
J93-GE-3
Production variant produced in small numbers for the North American XB-70 Valkyrie program.
J93-GE-3R
Variant with thrust reverser, 27,200 lbf (121 kN) thrust with afterburner.[7]
J93-GE-3AR
Variant intended for the North American XF-108 Rapier.

Applications[edit]

Specifications (J93-GE-3)[edit]

Data from Aircraft engines of the World 1966/77,[8] Military Turbojet/Turbofan Specifications,[9] North American XB-70A Valkyrie[1]

General characteristics

  • Type: Turbojet with afterburner
  • Length: 237 in (6,000 mm)
  • Diameter: 52.5 in (1,330 mm)
  • Dry weight: 5,000 lb (2,300 kg)

Components

  • Compressor: 11-stage axial
  • Combustors: Annular with 36 dual fuel nozzles
  • Turbine: Two-stage axial
  • Fuel type: Special high-temperature JP-6 Fuel to MIL-F-25656
  • Oil system: Return oil spray system at 60 psi (410 kPa)

Performance

  • Maximum thrust: 22,000 lbf (98 kN) dry; 30,000 lbf (130 kN) with afterburner
  • Air mass flow: 275 lb/s (125 kg/s)
  • Turbine inlet temperature: 1,149 °C (2,100 °F; 1,422 K)
  • Specific fuel consumption: 0.700 lb/(lbf⋅h) (19.8 g/(kN⋅s)) dry; 1.800 lb/(lbf⋅h) (51.0 g/(kN⋅s)) wet
  • Thrust-to-weight ratio: 6

See also[edit]

Related development

Comparable engines

Related lists

References[edit]

Wikimedia Commons has media related to General Electric YJ93.
  1. ^ a b Jenkins, Dennis R.; Landis, Tony (2002). North American XB-70A Valkyrie. North Branch [USA]: Specialty Press Publishers and Wholesalers. ISBN 1-58007-056-6.
  2. ^ a b Eight Decades of Progress : A Heritage of Aircraft Turbine Technology. GE Aircraft Engines. 1990. p. 117. LCCN 90082948.
  3. ^ Jenkins, Dennis R. and Tony R. Landis. Valkyrie: North American's Mach 3 Superbomber. North Branch, Minnesota: Specialty Press, 2005. ISBN 1-58007-072-8.
  4. ^ National Museum of the USAF Retrieved: December 21, 2016
  5. ^ NB-58A Testbed for General Electric J93 Archived 2008-07-24 at the Wayback Machine
  6. ^ "Characteristics Summary: F-108A" (PDF). US Air Force. 2 May 1958. Retrieved 15 December 2018.
  7. ^ "Characteristics Summary: F-108A" (PDF). US Air Force. 15 December 1958. Retrieved 15 December 2018.
  8. ^ Wilkinson, Paul H. (1966). Aircraft engines of the World 1966/77 (21st ed.). London: Sir Isaac Pitman & Sons Ltd. p. 83.
  9. ^ "Military Turbojet/Turbofan Specifications". www.jet-engine.net. Archived from the original on 2 October 2011. Retrieved 31 December 2017.
Retrieved from "https://en.wikipedia.org/w/index.php?title=General_Electric_YJ93&oldid=1196165089"