Liquid rocket propellants 1078982 225940486 2008-07-16T03:09:29Z Wolfkeeper 41690 Revert to revision 224579984 dated 2008-07-09 14:38:56 by Jonathan Cardy using [[:en:Wikipedia:Tools/Navigation_popups|popups]] The highest [[specific impulse]] chemical [[rocket]]s use '''liquid propellants'''. This type of propellent has a long history going back to the first rockets and is still in use in for example the [[Space Shuttle program|Space Shuttle]] and [[Ariane 5]]. == History == ===Early development=== [[Image:Goddard and Rocket.jpg|thumb|200px|right|[[Robert H. Goddard]] on [[March 16]], [[1926]], holding the launching frame of his most notable invention &mdash; the first liquid-fueled rocket.]] On [[March 16]], [[1926]], [[Robert H. Goddard]] used [[liquid oxygen]] and [[gasoline]] as [[Rocket fuel|propellant]]s for his first successful liquid rocket launch. Both are readily available, cheap, highly energetic, and dense. Oxygen is a moderate [[cryogen]] — air will not liquify against a liquid oxygen tank, so it is possible to store LOX briefly in a rocket without excessive insulation. Gasoline has since been replaced by [[RP-1]], a highly refined grade of [[kerosene]]. This combination is quite practical for rockets that need not be stored, and to this day, it is used in the [[Multistage rocket|first stage]]s of most orbital [[launcher]]s, as well as the long-range offensive [[missiles]] of [[China]] and [[North Korea]]. ===1950s=== During the 1950s there was a great burst of activity by propellant chemists to find high-energy liquid propellants better suited to the military. Military rockets need to sit in silos for many years, able to launch at a moment's notice. Propellants requiring continuous refrigeration, and which cause their rockets to grow ever-thicker blankets of ice, are not practical. As the military is willing to handle and use hazardous materials, a great number of dangerous chemicals were brewed up in large batches, virtually all of which were dead ends. For instance, in the case of [[nitric acid]], the acid itself (HNO<sub>3</sub>) is unstable, and gives off NO<sub>2</sub> fumes (hence the name white fuming nitric acid). Unlike [[nitrous oxide]] (N<sub>2</sub>O), these [[nitrogen dioxide]] fumes are extremely toxic. The addition of large amounts of [[dinitrogen tetroxide]] (N<sub>2</sub>O<sub>4</sub>) makes the mixture red, but keeps it from changing composition, leaving the problem that nitric acid will eat any container it is placed in, releasing gases that can build up pressure in the process. The breakthrough was the addition of a little [[hydrofluoric acid]] (HF), which forms a self-healing metal fluoride on the interior of tank walls and makes ''Inhibited'' Red Fuming Nitric Acid storable. Although the development of military propellants was treated with the greatest secrecy, the trick to inhibiting nitric acid was published shortly after its discovery in 1954 and Russian rockets with the same fuel appeared shortly afterwards, the first being the SS-1B ("[[Scud]]"). Eventually the chemists gave up stabilizing HNO<sub>3</sub> with N<sub>2</sub>O<sub>4</sub>, and just used straight N<sub>2</sub>O<sub>4</sub>, which is a slightly better oxidizer anyway. (In the propellant table below, note that N<sub>2</sub>O<sub>4</sub> is always in equilibrium with NO<sub>2</sub>, and so mixtures are sometimes quoted with the latter.) ===Hydrogen=== Many early rocket theorists believed that [[hydrogen]] would be a marvellous propellant, since it gives the highest [[specific impulse]]. As hydrogen in any state is very bulky, for flightweight vehicles it is typically stored as a deeply cryogenic liquid. This storage technique was mastered in the 1960s as part of the [[Saturn (rocket family)|Saturn]] and [[Centaur (rocket stage)|Centaur]] upper-stage programs. Even as a liquid, hydrogen has low density, requiring large, heavy tanks and pumps, and the extreme cold requires heavy and [[Space Shuttle Columbia disaster|potentially dangerous]] tank insulation. This extra weight reduces the mass fraction of the vehicle and offsets the specific impulse advantage. Most rockets that use hydrogen fuel use it in upper stages only, where a low thrust-to-empty-mass ratio can be tolerated and where a hydrogen stage's low total mass reduces the size of the lower stages. Those rockets that use hydrogen fuel in their lower stages, like the [[Space Shuttle program|Space Shuttle]], [[Delta IV rocket|Delta IV]], and [[Ariane 5]], often use powerful and dense solid rocket motors at liftoff to improve their acceleration off the pad and thus reduce gravity losses early in flight. ===Lithium/fluorine=== The highest specific impulse chemistry ever test-fired in a rocket engine was [[lithium]] and [[fluorine]], with hydrogen added to improve the exhaust thermodynamics (all propellants had to be kept in their own tanks, making this a [[Tripropellant rocket|tripropellant]]). The combination delivered 542 s specific impulse in a vacuum, equivalent to an exhaust velocity of 5320 m/s. The impracticality of this chemistry highlights why exotic propellants are not actually used: to make all three components liquids, the hydrogen must be kept below -252°C (just 21 K) and the lithium must be kept above 180°C (453 K). Lithium and fluorine are both extremely corrosive, lithium ignites on contact with air, fluorine ignites on contact with most fuels, and hydrogen, while not hypergolic, is an explosive hazard. Fluorine and the hydrogen fluoride (HF) in the exhaust are very toxic, which makes working around the launch pad difficult, damages the environment, and makes getting a launch license that much more difficult. The rocket exhaust is also ionized, which would interfere with radio communication with the rocket. Finally, both lithium and fluorine are expensive and rare, enough to actually matter. This combination has therefore never flown. ===Monopropellants=== *[[Hydrogen peroxide]] decomposes to steam and oxygen *[[Hydrazine]] decomposes energetically to nitrogen and hydrogen, making it a fairly good [[monopropellant]] all by itself. *[[Nitrous oxide]] decomposes to nitrogen and oxygen *[[Steam]] when externally heated gives a reasonably modest Isp of up to 190 seconds, depending on material corrosion and thermal limits == Current use == Here are some common liquid fuel combinations in use today: * LOX and kerosene (RP-1). Used for the lower stages of most Russian and Chinese boosters, and the first stage of the U.S. [[Saturn V]] and [[Atlas (rocket family)|Atlas]] boosters. Very similar to Robert Goddard's first rocket. * LOX and liquid hydrogen, used in the Space Shuttle, Ariane 5, Delta IV and the Centaur upper stage. * Nitrogen tetroxide (N<sub>2</sub>O<sub>4</sub>) and hydrazine (N<sub>2</sub>H<sub>4</sub>). Used in military, orbital and deep space rockets, because both liquids are storable for long periods at reasonable temperatures and pressures. ==Propellant table== <table class="toccolours" border="1" cellpadding="2" cellspacing="0" align="right" width="35%" style="float: right; clear: right; margin: 0 0 1em 1em; border-collapse: collapse;"> <tr><th colspan="2">To approximate Isp at other chamber pressures</th></tr> <tr> <th align="center">Absolute Pressure [[Atmosphere (unit)|(atm)]] [[Pound-force per square inch|{psi}]]</th> <th align="center">Multiply by</th> </tr> <tr><td align="center">6,895 k[[Pascal (unit)|Pa]] (68.05) {1000}</td><td align="center">1.00</td></tr> <tr><td align="center">6,205 kPa (61.24) {900}</td><td align="center">0.99</td></tr> <tr><td align="center">5,516 kPa (54.44) {800}</td><td align="center">0.98</td></tr> <tr><td align="center">4,826 kPa (47.63) {700}</td><td align="center">0.97</td></tr> <tr><td align="center">4,137 kPa (40.83) {600}</td><td align="center">0.95</td></tr> <tr><td align="center">3,447 kPa (34.02) {500}</td><td align="center">0.93</td></tr> <tr><td align="center">2,758 kPa (27.22) {400}</td><td align="center">0.91</td></tr> <tr><td align="center">2,068 kPa (20.41) {300}</td><td align="center">0.88</td></tr> </table> JANAF thermochemical data used throughout. Calculations performed by Rocketdyne, results appear in "Modern Engineering for Design of Liquid-Propellant Rocket Engines", Huzel and Huang. Some of the units have been converted to metric, but pressures have not. These are best-possible specific impulse calculations. Assumptions: * [[adiabatic]] combustion * [[isentropic]] expansion * one-dimensional expansion * shifting equilibrium Definitions <table> <tr><td>''r''</td><td>Mixture ratio: mass oxidizer / mass fuel</td></tr> <tr><td>''V<sub>e</sub>''</td><td>Average exhaust velocity, m/s. The same measure as specific impulse in different units, numerically equal to specific impulse in N·s/kg.</td></tr> <tr><td>''C*''</td><td>Characteristic velocity, m/s. Equal to chamber pressure multiplied by throat area, divided by [[mass flow rate]]. Used to check experimental rocket's combustion efficiency.</td></tr> <tr><td>''T<sub>c''</sub></td><td>Chamber temperature, °C</td></tr> <tr><td>''d''</td><td>[[Bulk density]] of fuel and oxidizer, g/cm³</td></tr> </table> ===Bipropellants=== <table class="wikitable" border="1" cellpadding="2" cellspacing="0" width="100%"> <tr> <th colspan="3"></th> <th colspan="5" style="border-right:2px solid grey;">Optimum expansion from<br>68.05 atm to 1 atm</th> <th colspan="5">Optimum expansion from<br>68.05 atm to 0 atm (vacuum) (Area<sub>nozzle</sub> = 40:1)</th> </tr> <tr> <th style="border-bottom:2px solid grey;">Oxidizer</td> <th style="border-bottom:2px solid grey;">Fuel</td> <th style="border-bottom:2px solid grey;">comment</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c''</sub></td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="10">[[LOX]]</td> <td>[[liquid hydrogen|H<sub>2</sub>]]</td> <td>common</td> <td align="right" >3816</td> <td align="right" >4.13</td> <td align="right" >2740</td> <td align="right" >0.29</td> <td align="right" style="border-right:2px solid grey;">2416</td> <td align="right" >4462</td> <td align="right" >4.83</td> <td align="right" >2978</td> <td align="right" >0.32</td> <td align="right" >2386</td> </tr> <tr> <td align="left" >H<sub>2</sub>-[[beryllium|Be]] 49/51</td> <td></td> <td align="right" >4498</td> <td align="right" >0.87</td> <td align="right" >2558</td> <td align="right" >0.23</td> <td align="right" style="border-right:2px solid grey;">2833</td> <td align="right" >5295</td> <td align="right" >0.91</td> <td align="right" >2589</td> <td align="right" >0.24</td> <td align="right" >2850</td> </tr> <tr> <td align="left" >[[methane|CH<sub>4</sub>]]</td> <td></td> <td align="right" >3034</td> <td align="right" >3.21</td> <td align="right" >3260</td> <td align="right" >0.82</td> <td align="right" style="border-right:2px solid grey;">1857</td> <td align="right" >3615</td> <td align="right" >3.45</td> <td align="right" >3290</td> <td align="right" >0.83</td> <td align="right" >1838</td> </tr> <tr> <td align="left" >[[ethane|C<sub>2</sub>H<sub>6</sub>]]</td> <td></td> <td align="right" >3006</td> <td align="right" >2.89</td> <td align="right" >3320</td> <td align="right" >0.90</td> <td align="right" style="border-right:2px solid grey;">1840</td> <td align="right" >3584</td> <td align="right" >3.10</td> <td align="right" >3351</td> <td align="right" >0.91</td> <td align="right" >1825</td> </tr> <tr> <td align="left" >[[ethylene|C<sub>2</sub>H<sub>4</sub>]]</td> <td></td> <td align="right" >3053</td> <td align="right" >2.38</td> <td align="right" >3486</td> <td align="right" >0.88</td> <td align="right" style="border-right:2px solid grey;">1875</td> <td align="right" >3635</td> <td align="right" >2.59</td> <td align="right" >3521</td> <td align="right" >0.89</td> <td align="right" >1855</td> </tr> <tr> <td align="left" >[[RP-1]]</td> <td>common</td> <td align="right" >2941</td> <td align="right" >2.58</td> <td align="right" >3403</td> <td align="right" >1.03</td> <td align="right" style="border-right:2px solid grey;" >1799</td> <td align="right" >3510</td> <td align="right" >2.77</td> <td align="right" >3428</td> <td align="right" >1.03</td> <td align="right" >1783</td> </tr> <tr> <td align="left" >[[hydrazine|N<sub>2</sub>H<sub>4]]</sub></td> <td></td> <td align="right" >3065</td> <td align="right" >0.92</td> <td align="right" >3132</td> <td align="right" >1.07</td> <td align="right" style="border-right:2px solid grey;">1892</td> <td align="right" >3460</td> <td align="right" >0.98</td> <td align="right" >3146</td> <td align="right" >1.07</td> <td align="right" >1878</td> </tr> <tr> <td align="left" >[[pentaborane|B<sub>5</sub>H<sub>9</sub>]]</td> <td></td> <td align="right" >3124</td> <td align="right" >2.12</td> <td align="right" >3834</td> <td align="right" >0.92</td> <td align="right" style="border-right:2px solid grey;">1895</td> <td align="right" >3758</td> <td align="right" >2.16</td> <td align="right" >3863</td> <td align="right" >0.92</td> <td align="right" >1894</td> </tr> <tr> <td align="left" >[[diborane|B<sub>2</sub>H<sub>6</sub>]]</td> <td></td> <td align="right" >3351</td> <td align="right" >1.96</td> <td align="right" >3489</td> <td align="right" >0.74</td> <td align="right" style="border-right:2px solid grey;">2041</td> <td align="right" >4016</td> <td align="right" >2.06</td> <td align="right" >3563</td> <td align="right" >0.75</td> <td align="right" >2039</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >CH<sub>4</sub>/H<sub>2</sub> 92.6/7.4</td> <td style="border-bottom:2px solid grey;" ></td> <td style="border-bottom:2px solid grey;" align="right" >3126</td> <td style="border-bottom:2px solid grey;" align="right" >3.36</td> <td style="border-bottom:2px solid grey;" align="right" >3245</td> <td style="border-bottom:2px solid grey;" align="right" >0.71</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1920</td> <td style="border-bottom:2px solid grey;" align="right" >3719</td> <td style="border-bottom:2px solid grey;" align="right" >3.63</td> <td style="border-bottom:2px solid grey;" align="right" >3287</td> <td style="border-bottom:2px solid grey;" align="right" >0.72</td> <td style="border-bottom:2px solid grey;" align="right" >1897</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[oxygen|GOX]]</td> <td style="border-bottom:2px solid grey;" align="left" >[[hydrogen|GH<sub>2</sub>]]</td> <td style="border-bottom:2px solid grey;" align="left" ></td> <td style="border-bottom:2px solid grey;" align="right" >3997</td> <td style="border-bottom:2px solid grey;" align="right" >3.29</td> <td style="border-bottom:2px solid grey;" align="right" >2576</td> <td style="border-bottom:2px solid grey;" align="left" >-</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">2550</td> <td style="border-bottom:2px solid grey;" align="right" >4485</td> <td style="border-bottom:2px solid grey;" align="right" >3.92</td> <td style="border-bottom:2px solid grey;" align="right" >2862</td> <td style="border-bottom:2px solid grey;" align="left" >-</td> <td style="border-bottom:2px solid grey;" align="right" >2519</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="9" align="left" >[[fluorine|F<sub>2</sub>]]</td> <td align="left" >[[liquid hydrogen|H<sub>2</sub>]]</td> <td></td> <td align="right" >4036</td> <td align="right" >7.94</td> <td align="right" >3689</td> <td align="right" >0.46</td> <td align="right" style="border-right:2px solid grey;">2556</td> <td align="right" >4697</td> <td align="right" >9.74</td> <td align="right" >3985</td> <td align="right" >0.52</td> <td align="right" >2530</td> </tr> <tr> <td align="left" >H<sub>2</sub>-[[lithium|Li]] 65.2/34.0</td> <td></td> <td align="right" >4256</td> <td align="right" >0.96</td> <td align="right" >1830</td> <td align="right" >0.19</td> <td align="right" style="border-right:2px solid grey;">2680</td> <td ></td> <td ></td> <td ></td> <td ></td> <td ></td> </tr> <tr> <td align="left" >H<sub>2</sub>-Li 60.7/39.3</td> <td></td> <td ></td> <td ></td> <td ></td> <td ></td> <td style="border-right:2px solid grey;"></td> <td align="right" >5050</td> <td align="right" >1.08</td> <td align="right" >1974</td> <td align="right" >0.21</td> <td align="right" >2656</td> </tr> <tr> <td align="left" >[[methane|CH<sub>4</sub>]]</td> <td></td> <td align="right" >3414</td> <td align="right" >4.53</td> <td align="right" >3918</td> <td align="right" >1.03</td> <td align="right" style="border-right:2px solid grey;">2068</td> <td align="right" >4075</td> <td align="right" >4.74</td> <td align="right" >3933</td> <td align="right" >1.04</td> <td align="right" >2064</td> </tr> <tr> <td align="left" >[[ethane|C<sub>2</sub>H<sub>6</sub>]]</td> <td></td> <td align="right" >3335</td> <td align="right" >3.68</td> <td align="right" >3914</td> <td align="right" >1.09</td> <td align="right" style="border-right:2px solid grey;">2019</td> <td align="right" >3987</td> <td align="right" >3.78</td> <td align="right" >3923</td> <td align="right" >1.10</td> <td align="right" >2014</td> </tr> <tr> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td></td> <td align="right" >3413</td> <td align="right" >2.39</td> <td align="right" >4074</td> <td align="right" >1.24</td> <td align="right" style="border-right:2px solid grey;">2063</td> <td align="right" >4071</td> <td align="right" >2.47</td> <td align="right" >4091</td> <td align="right" >1.24</td> <td align="right" >1987</td> </tr> <tr> <td align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]</td> <td></td> <td align="right" >3580</td> <td align="right" >2.32</td> <td align="right" >4461</td> <td align="right" >1.31</td> <td align="right" style="border-right:2px solid grey;">2219</td> <td align="right" >4215</td> <td align="right" >2.37</td> <td align="right" >4468</td> <td align="right" >1.31</td> <td align="right" >2122</td> </tr> <tr> <td align="left" >[[ammonia|NH<sub>3</sub>]]</td> <td></td> <td align="right" >3531</td> <td align="right" >3.32</td> <td align="right" >4337</td> <td align="right" >1.12</td> <td align="right" style="border-right:2px solid grey;">2194</td> <td align="right" >4143</td> <td align="right" >3.35</td> <td align="right" >4341</td> <td align="right" >1.12</td> <td align="right" >2193</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[pentaborane|B<sub>5</sub>H<sub>9</sub>]]</td> <td style="border-bottom:2px solid grey;"></td> <td style="border-bottom:2px solid grey;" align="right" >3502</td> <td style="border-bottom:2px solid grey;" align="right" >5.14</td> <td style="border-bottom:2px solid grey;" align="right" >5050</td> <td style="border-bottom:2px solid grey;" align="right" >1.23</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">2147</td> <td style="border-bottom:2px solid grey;" align="right" >4191</td> <td style="border-bottom:2px solid grey;" align="right" >5.58</td> <td style="border-bottom:2px solid grey;" align="right" >5083</td> <td style="border-bottom:2px solid grey;" align="right" >1.25</td> <td style="border-bottom:2px solid grey;" align="right" >2140</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="9" align="left" >[[oxygen difluoride|OF<sub>2</sub>]]</td> <td align="left" >[[liquid hydrogen|H<sub>2</sub>]]</td> <td></td> <td align="right" >4014</td> <td align="right" >5.92</td> <td align="right" >3311</td> <td align="right" >0.39</td> <td align="right" style="border-right:2px solid grey;">2542</td> <td align="right" >4679</td> <td align="right" >7.37</td> <td align="right" >3587</td> <td align="right" >0.44</td> <td align="right" >2499</td> </tr> <tr> <td align="left" >[[methane|CH<sub>4</sub>]]</td> <td></td> <td align="right" >3485</td> <td align="right" >4.94</td> <td align="right" >4157</td> <td align="right" >1.06</td> <td align="right" style="border-right:2px solid grey;">2160</td> <td align="right" >4131</td> <td align="right" >5.58</td> <td align="right" >4207</td> <td align="right" >1.09</td> <td align="right" >2139</td> </tr> <tr> <td align="left" >[[ethane|C<sub>2</sub>H<sub>6</sub>]]</td> <td></td> <td align="right" >3511</td> <td align="right" >3.87</td> <td align="right" >4539</td> <td align="right" >1.13</td> <td align="right" style="border-right:2px solid grey;">2176</td> <td align="right" >4137</td> <td align="right" >3.86</td> <td align="right" >4538</td> <td align="right" >1.13</td> <td align="right" >2176</td> </tr> <tr> <td align="left" >[[RP-1]]</td> <td></td> <td align="right" >3424</td> <td align="right" >3.87</td> <td align="right" >4436</td> <td align="right" >1.28</td> <td align="right" style="border-right:2px solid grey;">2132</td> <td align="right" >4021</td> <td align="right" >3.85</td> <td align="right" >4432</td> <td align="right" >1.28</td> <td align="right" >2130</td> </tr> <tr> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td></td> <td align="right" >3427</td> <td align="right" >2.28</td> <td align="right" >4075</td> <td align="right" >1.24</td> <td align="right" style="border-right:2px solid grey;">2119</td> <td align="right" >4067</td> <td align="right" >2.58</td> <td align="right" >4133</td> <td align="right" >1.26</td> <td align="right" >2106</td> </tr> <tr> <td align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]</td> <td></td> <td align="right" >3381</td> <td align="right" >1.51</td> <td align="right" >3769</td> <td align="right" >1.26</td> <td align="right" style="border-right:2px solid grey;">2087</td> <td align="right" >4008</td> <td align="right" >1.65</td> <td align="right" >3814</td> <td align="right" >1.27</td> <td align="right" >2081</td> </tr> <tr> <td align="left" >MMH/N<sub>2</sub>H<sub>4</sub>/[[water (molecule)|H<sub>2</sub>0]] 50.5/29.8/19.7</td> <td></td> <td align="right" >3286</td> <td align="right" >1.75</td> <td align="right" >3726</td> <td align="right" >1.24</td> <td align="right" style="border-right:2px solid grey;">2025</td> <td align="right" >3908</td> <td align="right" >1.92</td> <td align="right" >3769</td> <td align="right" >1.25</td> <td align="right" >2018</td> </tr> <tr> <td align="left" >[[diborane|B<sub>2</sub>H<sub>6</sub>]]</td> <td></td> <td align="right" >3653</td> <td align="right" >3.95</td> <td align="right" >4479</td> <td align="right" >1.01</td> <td align="right" style="border-right:2px solid grey;">2244</td> <td align="right" >4367</td> <td align="right" >3.98</td> <td align="right" >4486</td> <td align="right" >1.02</td> <td align="right" >2167</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[pentaborane|B<sub>5</sub>H<sub>9</sub>]]</td> <td style="border-bottom:2px solid grey;" ></td> <td style="border-bottom:2px solid grey;" align="right" >3539</td> <td style="border-bottom:2px solid grey;" align="right" >4.16</td> <td style="border-bottom:2px solid grey;" align="right" >4825</td> <td style="border-bottom:2px solid grey;" align="right" >1.20</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">2163</td> <td style="border-bottom:2px solid grey;" align="right" >4239</td> <td style="border-bottom:2px solid grey;" align="right" >4.30</td> <td style="border-bottom:2px solid grey;" align="right" >4844</td> <td style="border-bottom:2px solid grey;" align="right" >1.21</td> <td style="border-bottom:2px solid grey;" align="right" >2161</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="2" align="left" >[[fluorine|F<sub>2</sub>]]/[[oxygen|O<sub>2</sub>]] 30/70</td> <td align="left" >[[liquid hydrogen|H<sub>2</sub>]]</td> <td></td> <td align="right" >3871</td> <td align="right" >4.80</td> <td align="right" >2954</td> <td align="right" >0.32</td> <td align="right" style="border-right:2px solid grey;">2453</td> <td align="right" >4520</td> <td align="right" >5.70</td> <td align="right" >3195</td> <td align="right" >0.36</td> <td align="right" >2417</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[RP-1]]</td> <td style="border-bottom:2px solid grey;" ></td> <td style="border-bottom:2px solid grey;" align="right" >3103</td> <td style="border-bottom:2px solid grey;" align="right" >3.01</td> <td style="border-bottom:2px solid grey;" align="right" >3665</td> <td style="border-bottom:2px solid grey;" align="right" >1.09</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1908</td> <td style="border-bottom:2px solid grey;" align="right" >3697</td> <td style="border-bottom:2px solid grey;" align="right" >3.30</td> <td style="border-bottom:2px solid grey;" align="right" >3692</td> <td style="border-bottom:2px solid grey;" align="right" >1.10</td> <td style="border-bottom:2px solid grey;" align="right" >1889</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >F<sub>2</sub>/O<sub>2</sub> 70/30</td> <td style="border-bottom:2px solid grey;" align="left" >[[RP-1]]</td> <td style="border-bottom:2px solid grey;" ></td> <td style="border-bottom:2px solid grey;" align="right" >3377</td> <td style="border-bottom:2px solid grey;" align="right" >3.84</td> <td style="border-bottom:2px solid grey;" align="right" >4361</td> <td style="border-bottom:2px solid grey;" align="right" >1.20</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">2106</td> <td style="border-bottom:2px solid grey;" align="right" >3955</td> <td style="border-bottom:2px solid grey;" align="right" >3.84</td> <td style="border-bottom:2px solid grey;" align="right" >4361</td> <td style="border-bottom:2px solid grey;" align="right" >1.20</td> <td style="border-bottom:2px solid grey;" align="right" >2104</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >F<sub>2</sub>/O<sub>2</sub> 87.8/12.2</td> <td style="border-bottom:2px solid grey;" align="left" >[[monomethylhydrazine|MMH]]</td> <td style="border-bottom:2px solid grey;" ></td> <td style="border-bottom:2px solid grey;" align="right" >3525</td> <td style="border-bottom:2px solid grey;" align="right" >2.82</td> <td style="border-bottom:2px solid grey;" align="right" >4454</td> <td style="border-bottom:2px solid grey;" align="right" >1.24</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">2191</td> <td style="border-bottom:2px solid grey;" align="right" >4148</td> <td style="border-bottom:2px solid grey;" align="right" >2.83</td> <td style="border-bottom:2px solid grey;" align="right" >4453</td> <td style="border-bottom:2px solid grey;" align="right" >1.23</td> <td style="border-bottom:2px solid grey;" align="right" >2186</td> </tr> <tr> <th style="border-bottom:2px solid grey;">Oxidizer</td> <th style="border-bottom:2px solid grey;">Fuel</td> <th style="border-bottom:2px solid grey;">comment</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c''</sub></td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="6" align="left" >[[tetrafluorohydrazine|N<sub>2</sub>F<sub>4</sub>]]</td> <td align="left" >[[methane|CH<sub>4</sub>]]</td> <td></td> <td align="right" >3127</td> <td align="right" >6.44</td> <td align="right" >3705</td> <td align="right" >1.15</td> <td align="right" style="border-right:2px solid grey;">1917</td> <td align="right" >3692</td> <td align="right" >6.51</td> <td align="right" >3707</td> <td align="right" >1.15</td> <td align="right" >1915</td> </tr> <tr> <td align="left" >[[ethane|C<sub>2</sub>H<sub>4</sub>]]</td> <td></td> <td align="right" >3035</td> <td align="right" >3.67</td> <td align="right" >3741</td> <td align="right" >1.13</td> <td align="right" style="border-right:2px solid grey;">1844</td> <td align="right" >3612</td> <td align="right" >3.71</td> <td align="right" >3743</td> <td align="right" >1.14</td> <td align="right" >1843</td> </tr> <tr> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td></td> <td align="right" >3163</td> <td align="right" >3.35</td> <td align="right" >3819</td> <td align="right" >1.32</td> <td align="right" style="border-right:2px solid grey;">1928</td> <td align="right" >3730</td> <td align="right" >3.39</td> <td align="right" >3823</td> <td align="right" >1.32</td> <td align="right" >1926</td> </tr> <tr> <td align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]</td> <td></td> <td align="right" >3283</td> <td align="right" >3.22</td> <td align="right" >4214</td> <td align="right" >1.38</td> <td align="right" style="border-right:2px solid grey;">2059</td> <td align="right" >3827</td> <td align="right" >3.25</td> <td align="right" >4216</td> <td align="right" >1.38</td> <td align="right" >2058</td> </tr> <tr> <td align="left" >[[ammonia|NH<sub>3</sub>]]</td> <td></td> <td align="right" >3204</td> <td align="right" >4.58</td> <td align="right" >4062</td> <td align="right" >1.22</td> <td align="right" style="border-right:2px solid grey;">2020</td> <td align="right" >3723</td> <td align="right" >4.58</td> <td align="right" >4062</td> <td align="right" >1.22</td> <td align="right" >2021</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[pentaborane|B<sub>5</sub>H<sub>9</sub>]]</td> <td style="border-bottom:2px solid grey;" align="right" ></td> <td style="border-bottom:2px solid grey;" align="right" >3259</td> <td style="border-bottom:2px solid grey;" align="right" >7.76</td> <td style="border-bottom:2px solid grey;" align="right" >4791</td> <td style="border-bottom:2px solid grey;" align="right" >1.34</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1997</td> <td style="border-bottom:2px solid grey;" align="right" >3898</td> <td style="border-bottom:2px solid grey;" align="right" >8.31</td> <td style="border-bottom:2px solid grey;" align="right" >4803</td> <td style="border-bottom:2px solid grey;" align="right" >1.35</td> <td style="border-bottom:2px solid grey;" align="right" >1992</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="4" align="left" >[[chlorine pentafluoride|ClF<sub>5</sub>]]</td> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td></td> <td align="right" >2962</td> <td align="right" >2.82</td> <td align="right" >3577</td> <td align="right" >1.40</td> <td align="right" style="border-right:2px solid grey;">1837</td> <td align="right" >3488</td> <td align="right" >2.83</td> <td align="right" >3579</td> <td align="right" >1.40</td> <td align="right" >1837</td> </tr> <tr> <td align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]</td> <td></td> <td align="right" >3069</td> <td align="right" >2.66</td> <td align="right" >3894</td> <td align="right" >1.47</td> <td align="right" style="border-right:2px solid grey;">1935</td> <td align="right" >3580</td> <td align="right" >2.71</td> <td align="right" >3905</td> <td align="right" >1.47</td> <td align="right" >1934</td> </tr> <tr> <td align="left" >MMH/N<sub>2</sub>H<sub>4</sub> 86/14</td> <td></td> <td align="right" >2971</td> <td align="right" >2.78</td> <td align="right" >3575</td> <td align="right" >1.41</td> <td align="right" style="border-right:2px solid grey;">1844</td> <td align="right" >3498</td> <td align="right" >2.81</td> <td align="right" >3579</td> <td align="right" >1.41</td> <td align="right" >1844</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >MMH/N<sub>2</sub>H<sub>4</sub>/N<sub>2</sub>H<sub>5</sub>NO<sub>3</sub> 55/26/19</td> <td style="border-bottom:2px solid grey;"></td> <td style="border-bottom:2px solid grey;" align="right" >2989</td> <td style="border-bottom:2px solid grey;" align="right" >2.46</td> <td style="border-bottom:2px solid grey;" align="right" >3717</td> <td style="border-bottom:2px solid grey;" align="right" >1.46</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1864</td> <td style="border-bottom:2px solid grey;" align="right" >3500</td> <td style="border-bottom:2px solid grey;" align="right" >2.49</td> <td style="border-bottom:2px solid grey;" align="right" >3722</td> <td style="border-bottom:2px solid grey;" align="right" >1.46</td> <td style="border-bottom:2px solid grey;" align="right" >1863</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="2" align="left" >[[chlorine trifluoride|ClF<sub>3</sub>]]</td> <td align="left" >[[monomethylhydrazine|MMH]]/[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]/N<sub>2</sub>H<sub>5</sub>NO<sub>3</sub> 55/26/19</td> <td>[[hypergolic]]</td> <td align="right" >2789</td> <td align="right" >2.97</td> <td align="right" >3407</td> <td align="right" >1.42</td> <td align="right" style="border-right:2px solid grey;">1739</td> <td align="right" >3274</td> <td align="right" >3.01</td> <td align="right" >3413</td> <td align="right" >1.42</td> <td align="right" >1739</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]</td> <td style="border-bottom:2px solid grey;">[[hypergolic]]</td> <td style="border-bottom:2px solid grey;" align="right" >2885</td> <td style="border-bottom:2px solid grey;" align="right" >2.81</td> <td style="border-bottom:2px solid grey;" align="right" >3650</td> <td style="border-bottom:2px solid grey;" align="right" >1.49</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1824</td> <td style="border-bottom:2px solid grey;" align="right" >3356</td> <td style="border-bottom:2px solid grey;" align="right" >2.89</td> <td style="border-bottom:2px solid grey;" align="right" >3666</td> <td style="border-bottom:2px solid grey;" align="right" >1.50</td> <td style="border-bottom:2px solid grey;" align="right" >1822</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="9" align="left" >[[dinitrogen tetroxide|N<sub>2</sub>O<sub>4</sub>]]</td> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td>[[hypergolic]], common</td> <td align="right" >2827</td> <td align="right" >2.17</td> <td align="right" >3122</td> <td align="right" >1.19</td> <td align="right" style="border-right:2px solid grey;">1745</td> <td align="right" >3347</td> <td align="right" >2.37</td> <td align="right" >3125</td> <td align="right" >1.20</td> <td align="right" >1724</td> </tr> <tr> <td align="left" >[[monomethylhydrazine|MMH]]/[[beryllium|Be]] 76.6/29.4</td> <td></td> <td align="right" >3106</td> <td align="right" >0.99</td> <td align="right" >3193</td> <td align="right" >1.17</td> <td align="right" style="border-right:2px solid grey;">1858</td> <td align="right" >3720</td> <td align="right" >1.10</td> <td align="right" >3451</td> <td align="right" >1.24</td> <td align="right" >1849</td> </tr> <tr> <td align="left" >MMH/[[aluminium|Al]] 63/27</td> <td></td> <td align="right" >2891</td> <td align="right" >0.85</td> <td align="right" >3294</td> <td align="right" >1.27</td> <td align="right" style="border-right:2px solid grey;">1785</td> <td ></td> <td ></td> <td ></td> <td ></td> <td ></td> </tr> <tr> <td align="left" >MMH/Al 58/42</td> <td></td> <td ></td> <td ></td> <td ></td> <td ></td> <td style="border-right:2px solid grey;"></td> <td align="right" >3460</td> <td align="right" >0.87</td> <td align="right" >3450</td> <td align="right" >1.31</td> <td align="right" >1771</td> </tr> <tr> <td align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]</td> <td>[[hypergolic]], common</td> <td align="right" >2862</td> <td align="right" >1.36</td> <td align="right" >2992</td> <td align="right" >1.21</td> <td align="right" style="border-right:2px solid grey;">1781</td> <td align="right" >3369</td> <td align="right" >1.42</td> <td align="right" >2993</td> <td align="right" >1.22</td> <td align="right" >1770</td> </tr> <tr> <td align="left" >N<sub>2</sub>H<sub>4</sub>/[[unsymmetrical dimethylhydrazine|UDMH]] 50/50</td> <td>[[hypergolic]], common</td> <td align="right" >2831</td> <td align="right" >1.98</td> <td align="right" >3095</td> <td align="right" >1.12</td> <td align="right" style="border-right:2px solid grey;">1747</td> <td align="right" >3349</td> <td align="right" >2.15</td> <td align="right" >3096</td> <td align="right" >1.20</td> <td align="right" >1731</td> </tr> <tr> <td align="left" >N<sub>2</sub>H<sub>4</sub>/Be 80/20</td> <td></td> <td align="right" >3209</td> <td align="right" >0.51</td> <td align="right" >3038</td> <td align="right" >1.20</td> <td align="right" style="border-right:2px solid grey;">1918</td> <td ></td> <td ></td> <td ></td> <td ></td> <td ></td> </tr> <tr> <td align="left" >N<sub>2</sub>H<sub>4</sub>/Be 76.6/23.4</td> <td></td> <td ></td> <td ></td> <td ></td> <td ></td> <td style="border-right:2px solid grey;"></td> <td align="right" >3849</td> <td align="right" >0.60</td> <td align="right" >3230</td> <td align="right" >1.22</td> <td align="right" >1913</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[pentaborane|B<sub>5</sub>H<sub>9</sub>]]</td> <td style="border-bottom:2px solid grey;" align="right" ></td> <td style="border-bottom:2px solid grey;" align="right" >2927</td> <td style="border-bottom:2px solid grey;" align="right" >3.18</td> <td style="border-bottom:2px solid grey;" align="right" >3678</td> <td style="border-bottom:2px solid grey;" align="right" >1.11</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1782</td> <td style="border-bottom:2px solid grey;" align="right" >3513</td> <td style="border-bottom:2px solid grey;" align="right" >3.26</td> <td style="border-bottom:2px solid grey;" align="right" >3706</td> <td style="border-bottom:2px solid grey;" align="right" >1.11</td> <td style="border-bottom:2px solid grey;" align="right" >1781</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="2" align="left" >[[nitric oxide|NO]]/[[dinitrogen tetroxide|N<sub>2</sub>O<sub>4</sub>]] 25/75</td> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td></td> <td align="right" >2839</td> <td align="right" >2.28</td> <td align="right" >3153</td> <td align="right" >1.17</td> <td align="right" style="border-right:2px solid grey;">1753</td> <td align="right" >3360</td> <td align="right" >2.50</td> <td align="right" >3158</td> <td align="right" >1.18</td> <td align="right" >1732</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]/[[beryllium|Be]] 76.6/23.4</td> <td style="border-bottom:2px solid grey;"></td> <td style="border-bottom:2px solid grey;" align="right" >2872</td> <td style="border-bottom:2px solid grey;" align="right" >1.43</td> <td style="border-bottom:2px solid grey;" align="right" >3023</td> <td style="border-bottom:2px solid grey;" align="right" >1.19</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1787</td> <td style="border-bottom:2px solid grey;" align="right" >3381</td> <td style="border-bottom:2px solid grey;" align="right" >1.51</td> <td style="border-bottom:2px solid grey;" align="right" >3026</td> <td style="border-bottom:2px solid grey;" align="right" >1.20</td> <td style="border-bottom:2px solid grey;" align="right" >1775</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="3" align="left" >[[inhibited red fuming nitric acid|IRFNA IIIa]]</td> <td align="left" >[[unsymmetrical dimethylhydrazine|UDMH]]/[[diethylenetriamine|DETA]] 60/40</td> <td>[[hypergolic]]</td> <td align="right" >2638</td> <td align="right" >3.26</td> <td align="right" >2848</td> <td align="right" >1.30</td> <td align="right" style="border-right:2px solid grey;">1627</td> <td align="right" >3123</td> <td align="right" >3.41</td> <td align="right" >2839</td> <td align="right" >1.31</td> <td align="right" >1617</td> </tr> <tr> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td>[[hypergolic]]</td> <td align="right" >2690</td> <td align="right" >2.59</td> <td align="right" >2849</td> <td align="right" >1.27</td> <td align="right" style="border-right:2px solid grey;">1665</td> <td align="right" >3178</td> <td align="right" >2.71</td> <td align="right" >2841</td> <td align="right" >1.28</td> <td align="right" >1655</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[unsymmetrical dimethylhydrazine|UDMH]]</td> <td style="border-bottom:2px solid grey;">[[hypergolic]]</td> <td style="border-bottom:2px solid grey;" align="right" >2668</td> <td style="border-bottom:2px solid grey;" align="right" >3.13</td> <td style="border-bottom:2px solid grey;" align="right" >2874</td> <td style="border-bottom:2px solid grey;" align="right" >1.26</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1648</td> <td style="border-bottom:2px solid grey;" align="right" >3157</td> <td style="border-bottom:2px solid grey;" align="right" >3.31</td> <td style="border-bottom:2px solid grey;" align="right" >2864</td> <td style="border-bottom:2px solid grey;" align="right" >1.27</td> <td style="border-bottom:2px solid grey;" align="right" >1634</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="3" align="left" >[[inhibited red fuming nitric acid|IRFNA IV HDA]]</td> <td align="left" >[[unsymmetrical dimethylhydrazine|UDMH]]/[[diethylenetriamine|DETA]] 60/40</td> <td>[[hypergolic]]</td> <td align="right" >2689</td> <td align="right" >3.06</td> <td align="right" >2903</td> <td align="right" >1.32</td> <td align="right" style="border-right:2px solid grey;">1656</td> <td align="right" >3187</td> <td align="right" >3.25</td> <td align="right" >2951</td> <td align="right" >1.33</td> <td align="right" >1641</td> </tr> <tr> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td>[[hypergolic]]</td> <td align="right" >2742</td> <td align="right" >2.43</td> <td align="right" >2953</td> <td align="right" >1.29</td> <td align="right" style="border-right:2px solid grey;">1696</td> <td align="right" >3242</td> <td align="right" >2.58</td> <td align="right" >2947</td> <td align="right" >1.31</td> <td align="right" >1680</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[unsymmetrical dimethylhydrazine|UDMH]]</td> <td style="border-bottom:2px solid grey;">[[hypergolic]]</td> <td style="border-bottom:2px solid grey;" align="right" >2719</td> <td style="border-bottom:2px solid grey;" align="right" >2.95</td> <td style="border-bottom:2px solid grey;" align="right" >2983</td> <td style="border-bottom:2px solid grey;" align="right" >1.28</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1676</td> <td style="border-bottom:2px solid grey;" align="right" >3220</td> <td style="border-bottom:2px solid grey;" align="right" >3.12</td> <td style="border-bottom:2px solid grey;" align="right" >2977</td> <td style="border-bottom:2px solid grey;" align="right" >1.29</td> <td style="border-bottom:2px solid grey;" align="right" >1662</td> </tr> <tr> <td style="border-bottom:2px solid grey;" rowspan="4" align="left" >[[hydrogen peroxide|H<sub>2</sub>O<sub>2</sub>]]</td> <td align="left" >[[monomethylhydrazine|MMH]]</td> <td></td> <td align="right" >2790</td> <td align="right" >3.46</td> <td align="right" >2720</td> <td align="right" >1.24</td> <td align="right" style="border-right:2px solid grey;">1726</td> <td align="right" >3301</td> <td align="right" >3.69</td> <td align="right" >2707</td> <td align="right" >1.24</td> <td align="right" >1714</td> </tr> <tr> <td align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]</td> <td></td> <td align="right" >2810</td> <td align="right" >2.05</td> <td align="right" >2651</td> <td align="right" >1.24</td> <td align="right" style="border-right:2px solid grey;">1751</td> <td align="right" >3308</td> <td align="right" >2.12</td> <td align="right" >2645</td> <td align="right" >1.25</td> <td align="right" >1744</td> </tr> <tr> <td align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]/[[beryllium|Be]] 74.5/25.5</td> <td></td> <td align="right" >3289</td> <td align="right" >0.48</td> <td align="right" >2915</td> <td align="right" >1.21</td> <td align="right" style="border-right:2px solid grey;">1943</td> <td align="right" >3954</td> <td align="right" >0.57</td> <td align="right" >3098</td> <td align="right" >1.24</td> <td align="right" >1940</td> </tr> <tr> <td style="border-bottom:2px solid grey;" align="left" >[[pentaborane|B<sub>5</sub>H<sub>9</sub>]]</td> <td style="border-bottom:2px solid grey;"></td> <td style="border-bottom:2px solid grey;" align="right" >3016</td> <td style="border-bottom:2px solid grey;" align="right" >2.20</td> <td style="border-bottom:2px solid grey;" align="right" >2667</td> <td style="border-bottom:2px solid grey;" align="right" >1.02</td> <td style="border-bottom:2px solid grey; border-right:2px solid grey;" align="right">1828</td> <td style="border-bottom:2px solid grey;" align="right" >3642</td> <td style="border-bottom:2px solid grey;" align="right" >2.09</td> <td style="border-bottom:2px solid grey;" align="right" >2597</td> <td style="border-bottom:2px solid grey;" align="right" >1.01</td> <td style="border-bottom:2px solid grey;" align="right" >1817</td> </tr> <tr> <td rowspan="2" align="left" >[[hydrazine|N<sub>2</sub>H<sub>4</sub>]]</td> <td align="left" >[[diborane|B<sub>2</sub>H<sub>6</sub>]]</td> <td></td> <td align="right" >3342</td> <td align="right" >1.16</td> <td align="right" >2231</td> <td align="right" >0.63</td> <td align="right" style="border-right:2px solid grey;">2080</td> <td align="right" >3953</td> <td align="right" >1.16</td> <td align="right" >2231</td> <td align="right" >0.63</td> <td align="right" >2080</td> </tr> <tr> <td align="left" >[[pentaborane|B<sub>5</sub>H<sub>9</sub>]]</td> <td></td> <td align="right" >3204</td> <td align="right" >1.27</td> <td align="right" >2441</td> <td align="right" >0.80</td> <td align="right" style="border-right:2px solid grey;">1960</td> <td align="right" >3819</td> <td align="right" >1.27</td> <td align="right" >2441</td> <td align="right" >0.80</td> <td align="right" >1960</td> </tr> <tr> <th style="border-bottom:2px solid grey;">Oxidizer</td> <th style="border-bottom:2px solid grey;">Fuel</td> <th style="border-bottom:2px solid grey;">comment</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c''</sub></td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> </tr> </table> Definitions of some of the mixtures: * [[inhibited red fuming nitric acid|IRFNA IIIa]]: 83.4% [[nitric acid|HNO<sub>3</sub>]], 14% [[nitrogen dioxide|NO<sub>2</sub>]], 2% [[water (molecule)|H<sub>2</sub>O]], 0.6% [[hydrogen fluoride|HF]] * IRFNA IV HDA: 54.3% HNO<sub>3</sub>, 44% NO<sub>2</sub>, 1% H<sub>2</sub>O, 0.7% HF * [[RP-1]]: see MIL-P-25576C, basically [[kerosene]] (approximately C<sub>10</sub>H<sub>18</sub>) * [[monomethylhydrazine|MMH]]: CH<sub>3</sub>NHNH<sub>2</sub> <table> <tr><td>''r''</td><td>Mixture ratio: mass oxidizer / mass fuel</td></tr> <tr><td>''V<sub>e</sub>''</td><td>Average exhaust velocity, m/s. The same measure as specific impulse in different units, numerically equal to specific impulse in N·s/kg.</td></tr> <tr><td>''C*''</td><td>Characteristic velocity, m/s. Equal to chamber pressure multiplied by throat area, divided by [[mass flow rate]]. Used to check experimental rocket's combustion efficiency.</td></tr> <tr><td>''T<sub>c''</sub></td><td>Chamber temperature, °C</td></tr> <tr><td>''d''</td><td>[[Bulk density]] of fuel and oxidizer, g/cm³</td></tr> </table> ===Monopropellants=== <table class="wikitable" border="1" cellpadding="2" cellspacing="0" width="100%"> <tr> <th colspan="3"></th> <th colspan="5" style="border-right:2px solid grey;">Optimum expansion from<br>68.05 atm to 1 atm</th> <th colspan="5">Optimum expansion from<br>68.05 atm to 0 atm (vacuum) (Area<sub>nozzle</sub> = 40:1)</th> </tr> <tr> <th style="border-bottom:2px solid grey;">Propellant</td> <th style="border-bottom:2px solid grey;">comment</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c''</sub></td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> </tr> <tr> <td>[[Hydrazine]]</td> <td>common</td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> <td align="right" style="border-right:2px solid grey;"></td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> </tr> <tr> <td>[[Hydrogen peroxide]]</td> <td>common</td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> <td align="right" style="border-right:2px solid grey;"></td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> <td align="right" ></td> </tr> <tr> <th style="border-bottom:2px solid grey;">Propellant</td> <th style="border-bottom:2px solid grey;">comment</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c''</sub></td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> <td style="border-bottom:2px solid grey;text-align:right;">''V<sub>e</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''r''</td> <td style="border-bottom:2px solid grey;text-align:right;">''T<sub>c</sub>''</td> <td style="border-bottom:2px solid grey;text-align:right;">''d''</td> <td style="border-bottom:2px solid grey;text-align:right;">''C*''</td> </tr> </table> ==See also== * [http://rocketworkbench.sourceforge.net/equil.phtml Cpropep-Web] an online computer program to calculate propellant performance in rocket engines [[Category:Spacecraft propulsion]] [[Category:Rocket propellants]]