Difference between revisions of "J-33 "Wheesley" Turbofan Engine"

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== Usage ==
 
== Usage ==
This engine is the second air breathing engine to unlock in the tech tree. As on all engines, thrust varies with height. Contrary to all rocket engines, air breathing engines' thrust diminishes with increasing height. Furthermore differing from most rocket engines, this has a real impact on usage, as the effect is far more distinct.
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This engine is the second air-breathing engine which can be unlocked in the [[Technology tree|tech tree]], after the [[J-20 "Juno" Basic Jet Engine|J-20 "Juno"]].
  
Its maximum '''stationary''' thrust is rated with 80 kN at sea level. At about 4000 m it generates just 47 kN, at about 11000 m it generates not more than 8 kN, ceasing to work at about 15600 m. Note that  the behaviour between these points (given in the part stats)is somewhat non-linear, especially above 4000 m.
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Unlike many of the other jet engines (and all of the rockets), this engine is capable of reversing its thrust. This makes it very useful for backing aircraft into hangars and for rapid deceleration during landing. The only other engine capable of this feat is the enormous [[J-90 "Goliath" Turbofan Engine|J-90 "Goliath"]].  
  
Thrust output also varies with '''speed''', although far less then on the more advanced engines. Up to mach 0.6 it stays somewhat constant, slightly rising to a maximum of about 170% at mach 1.6 – 1.8, dropping to zero at mach 2.5.
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As with all jet engines, its thrust decreases significantly with altitude. Its maximum '''stationary''' thrust is rated at 80 kN at sea level. At about 4,000 m it generates just 47 kN, and at about 11,000 m it generates no more than 8 kN, ceasing to work entirely at about 15,600 m. Note that the behavior between these points (as shown in the part stats) is somewhat non-linear, especially above 4,000 m.
  
The [[Specific_impulse|I<sub>sp</sub>]] stays constant over the full range of application, which is a big change to KSP pre 1.0 versions. It is rated at 9600 s, making it the nominal most fuel efficient engine. However, as the thrust/height curve of this engine limits its usage to still quite thick air, this value is somewhat put into perspective.
+
Thrust output also varies with '''speed''', although far less then on the more advanced engines. Up to mach 0.6 it stays somewhat constant, slightly rising to a maximum of about 170% at mach 1.6 – 1.8, and then dropping to zero at mach 2.5.
  
All in all, it works best at 8000 – 12000 m height. Flying lower, the high air resistance requires more thrust which lowers the fuel efficiency, while in higher areas the engines thrust output is just too low for reasonable flight.  
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The [[Specific_impulse|I<sub>sp</sub>]] stays constant over the full range of application, which is a big change compared to KSP in pre-1.0 versions. It is rated at 9,600 s, making it the nominal most fuel-efficient engine. However, as the thrust/height curve of this engine limits its usage to comparatively thick air which where drag remains a substantial impediment to high airspeed, this value is somewhat put into perspective.
  
Note that currently, the only planets which these engines will work on are [[Kerbin]] and [[Jool]]'s moon [[Laythe]].
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Overall, it works best between 8,000 – 12,000 m altitude. Flying lower, the high air resistance requires more thrust which lowers the fuel efficiency, while in higher areas the engine's thrust output is simply too low for reasonable performance in flight.
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Note that currently, the only planets which this engine will work on are [[Kerbin]] and [[Jool]]'s moon [[Laythe]].
  
 
== Product description ==
 
== Product description ==

Revision as of 23:43, 16 January 2016

J-33 "Wheesley" Turbofan Engine
Part image
Jet engine by
C7 Aerospace Division
Radial size Small
Cost (total) 1 400.00 Funds
Mass (total) 1.50 t
Drag 0.2
Max. Temp. 2000 K
Impact Tolerance 7 m/s
Research Tech tree aerodynamics.png Aerodynamics
Unlock cost 4 000 Funds
Since version 0.15
Part configuration jetEngineBasic
Jet engine
Maximum thrust 120 kN
Isp (max) 10500 s
Fuel consumption 0.23 Units of fuel/s
Intake air consumption 29.60 Air unit/s
Thrust vectoring × No
Testing Environments
On the surface ✓ Yes
In the ocean ✓ Yes
On the launchpad ✓ Yes
In the atmosphere ✓ Yes
Sub orbital × No
In an orbit × No
On an escape × No
Docked × No
Test by staging ✓ Yes
Manually testable ✓ Yes

The J-33 "Wheesely" Turbofan Engine is an air-breathing engine which uses liquid fuel and intake air.

Usage

This engine is the second air-breathing engine which can be unlocked in the tech tree, after the J-20 "Juno".

Unlike many of the other jet engines (and all of the rockets), this engine is capable of reversing its thrust. This makes it very useful for backing aircraft into hangars and for rapid deceleration during landing. The only other engine capable of this feat is the enormous J-90 "Goliath".

As with all jet engines, its thrust decreases significantly with altitude. Its maximum stationary thrust is rated at 80 kN at sea level. At about 4,000 m it generates just 47 kN, and at about 11,000 m it generates no more than 8 kN, ceasing to work entirely at about 15,600 m. Note that the behavior between these points (as shown in the part stats) is somewhat non-linear, especially above 4,000 m.

Thrust output also varies with speed, although far less then on the more advanced engines. Up to mach 0.6 it stays somewhat constant, slightly rising to a maximum of about 170% at mach 1.6 – 1.8, and then dropping to zero at mach 2.5.

The Isp stays constant over the full range of application, which is a big change compared to KSP in pre-1.0 versions. It is rated at 9,600 s, making it the nominal most fuel-efficient engine. However, as the thrust/height curve of this engine limits its usage to comparatively thick air which where drag remains a substantial impediment to high airspeed, this value is somewhat put into perspective.

Overall, it works best between 8,000 – 12,000 m altitude. Flying lower, the high air resistance requires more thrust which lowers the fuel efficiency, while in higher areas the engine's thrust output is simply too low for reasonable performance in flight.

Note that currently, the only planets which this engine will work on are Kerbin and Jool's moon Laythe.

Product description

A standard air breathing engine. This model utilizes limited range thrust vectoring. This engine works best at low cruising speeds and altitudes.

Created by: C. Jenkins

Triva

The designation “J-33 Wheesley” may be a reference to the real-life JT3D turbofan jet engine, also known as the TF33, made by U.S. aerospace company Pratt & Whitney which was involved with the Space Race.

Changes

Appearance before 1.0.5
1.0.5
  • Remodeled and retextured
1.0.3
  • Isp halved, thrust reduced
1.0
  • complete overhaul of most characteristics
0.15
  • Initial Release