Verniers/Engines

http://en.wikipedia.org/wiki/Vernier_thruster     http://wiki.kerbalspaceprogram.com/wiki/Category:Reaction_Systems_Ltd.

Rocketdyne's LR-101 was a small, secondary (or "vernier") engine. Two LR-101s were mounted on the Atlas and Thor missiles (and, later, the Delta launch vehicle, by virtue of its first stage being a modified Thor missile). It was produced in several versions and operated under different conditions, but the LR-101 generally produced about 1,000 pounds of thrust. Later, in its Atlas Space Launch Vehicle configuration, its thrust was downrated as adequate role and attitude control could be accomplished at a lower thrust rate and the corresponding lower propellant flowrate meant that more propellant was available to the sustainer engine, in turn producing improved overall launch vehicle performance.

On the Atlas, the two outer booster engines were gimballed; two gimballed engines allowed for yaw, pitch, and roll control. After about two minutes of flight, the boosters were jettisoned, leaving the single center sustainer engine. While this engine was also gimballed, roll control is not possible with only one engine. The primary purpose of the LR-101 vernier engines was to provide roll control after the booster engines had been jettisoned. They also contributed to thrust and, after the sustainer was shut down, powered the Atlas to its final velocity and position.

The LR-101 was a single-start, fixed-thrust engine with an expansion ration of 6:1. In at least some configurations, ignition occurred by means of pyrophoric (hypergolic) fluid which ignites spontaneously in the presence of oxygen. (A former Rocketdyne employee contacted me after I initially put up this page saying that in the July 1956 to July 1957 timeframe, they were ignited "by a sparkler stuck in the throat". The LR-101 was a long-lived engine, so it appears that different versions were ignited via different methods.) Its thrust chamber weighed only about 15 pounds; in its -NA-15 configuration, the mount and bearing assembly added another 27 pounds.

Here is a cut-away diagram of the LR-101 thrust chamber assembly: LR101-NA-1

1000 lb. Thrust


 * RJ-1 (MIL-F-25558B) has been utilized in the LR101-NA-11 **325 sec for LR101-NA-7


 * At altitudes above 100,000 ft, the thrust is approximately 1154 lb and specific impulse is 238 lbf-sec/lbm for the NA-13   Image002.pngImagesvst.jpg  Abstract : Presented is a summary of test results from a program to develop the YLR101-NA-15 vernier engine. The program was completed in three phases: (1) Downrating the tank-fed thrust of the YLR101-NA-13 vernier from 830 pounds to 525 pounds, (2) modifying and repackaging the 525pound-thrust vernier into the YLR101-NA-15 configuration, and (3) developing a modified vernier injector to minimize a thrust chamber erosion problem which P1127-2.gifFigs_7_Engine_gas_flow.jpgred at the 525-pound-thrust level.

Descriptors :    *LIQUID PROPELLANT ROCKET ENGINES, *SURFACE TO SURFACE MISSILES, *VERNIER ROCKET ENGINES, TEMPERATURE, PERFORMANCE(ENGINEERING), ACCELERATION, CONTAINERS, SPECIFIC IMPULSE, CAPTIVE TESTS, FUEL INJECTION, MOVABLE ROCKET ENGINES, SUSTAINER ENGINES, JET MIXING FLOW, THRUST CHAMBERS, GIMBALS, FLUID FLOW, THRUST, FUEL INJECTORS, EROSION, CONFIGURATIONS, COMBUSTION CHAMBERS

n the fictional Star Trek universe, the impulse drive is the method of propulsion that starships and other spacecraft use when they are travelling below the speed of light.[1] Typically powered by deuterium fusion reactors, impulse engines let ships travel interplanetary distances readily. For example, Starfleet Academy cadets use impulse engines when flying from Earth to Saturn and back.[citation needed]

There are three practical challenges surrounding impulse drive design: acceleration, time dilation and energy conservation. In the show, inertial dampers compensate for acceleration. These hypothetical devices would have to be set so that the propellant retained its inertia after leaving the craft otherwise the drive would be ineffective.[2] Time dilation would become noticeable at appreciable fractions of the speed of light. Regarding energy conservation, the television series and books offer two explanations:
 * Star Trek: The Next Generation Technical Manual indicates that the impulse engines are nuclear fusion engines where the plasma from the fusion reactor powers a massive magnetic coil to propel the ship. It is a form of magnetohydrodynamic or magnetoplasmadynamic thruster. This is used in conjunction with the ship's warp drive's alteration of the ship's relativistic mass, to achieve mid-to-high sub-light speeds. Thrusters, on the other hand, are closer to the designs of a high-efficiency reactant propellant (i.e. a sophisticated rocket engine) and are usually used for high-precision maneuvers. Ion propulsion drives are explicitly detailed to be used in Star Trek by Dominion and Iconian Starships and facilities.
 * Since a ship traveling at impulse velocities (slower than, but approaching, the speed of light) is still traveling in the normal space-time continuum, concerns Rcs.gifReacti44.jpg time dilation apply, and it is written in the ST:TNG Technical Manual that high relativistic speeds are avoided unless absolutely necessary; impulse power is therefore customarily limited to a maximum of 1⁄4 lightspeed. (Warp travel, on the other hand, is stated in the Manual to cause no kinds of time dilation effects.)Concept-all-1.jpg
 * Cr.jpgCryeng.jpgHeatex_flow_1024.jpgIndexeng.jpgIndexcry.jpgSpace_engines_by_mattiasa-d64qsaa.jpgIndexrbtc.jpgVstol-2.gifVernier-location.jpg
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm
 *   http://en.memory-alpha.wikia.com/wiki/Category:Propulsion_technology     http://stargate.wikia.com/wiki/Maneuvering_thruster                                                                   http://www.ex-astris-scientia.org/inconsistencies/treknology-power.htm