https://lcas.otaski.org/index.php?title=Main_Page&feed=atom&action=historyMain Page - Revision history2024-03-28T14:24:55ZRevision history for this page on the wikiMediaWiki 1.40.0https://lcas.otaski.org/index.php?title=Main_Page&diff=576&oldid=prevVincent: /* News */ SpaceUp2017-11-06T00:55:28Z<p><span dir="auto"><span class="autocomment">News: </span> SpaceUp</span></p>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">'''''October 2017:''''' A talk was made at SpaceUp about the use of nano-spacecraft as a cheap way to explore the solar system (spoiler: there is no cheap way). See the [[:File:Solar_system_exploration_with_cubesats.pdf|presentation]].</ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2015:''''' CFD is has resumed for a few months. Basic [[Telemetry|RF telemetry]] has been validated using a high-altitude balloon, thanks to the resources of [https://ukhas.co.uk/ ukhas], but for a rocket, a much more important data rate is required. That would either require more directional receiving antennas or a more powerful emitter, which requires an amateur radio license.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2015:''''' CFD is has resumed for a few months. Basic [[Telemetry|RF telemetry]] has been validated using a high-altitude balloon, thanks to the resources of [https://ukhas.co.uk/ ukhas], but for a rocket, a much more important data rate is required. That would either require more directional receiving antennas or a more powerful emitter, which requires an amateur radio license.</div></td></tr>
</table>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=574&oldid=prevVincent: /* News */ 2015 update2015-12-27T16:17:15Z<p><span dir="auto"><span class="autocomment">News: </span> 2015 update</span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 16:17, 27 December 2015</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">'''''December 2015:''''' CFD is has resumed for a few months. Basic [[Telemetry|RF telemetry]] has been validated using a high-altitude balloon, thanks to the resources of [https://ukhas.co.uk/ ukhas], but for a rocket, a much more important data rate is required. That would either require more directional receiving antennas or a more powerful emitter, which requires an amateur radio license.</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Most pages on this wiki are outdated or unfinished and would not be useful for somebody familiar with aerospace. There is one page that can be still useful, about [[Rocket:First_approximations|rocket mass estimation]]. A simple program was developed and some graphs are shown at the bottom, to easily compute and visualise which parameters cause the mass of an air-to-orbit rocket to change.</ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2013:''''' CFD has been stalled for a few months. In parallel, work on [[Telemetry|RF telemetry]] has started. First prototype will be tested in a high-altitude balloon in August 2014, in order to validate the RF module and the ground receiver.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2013:''''' CFD has been stalled for a few months. In parallel, work on [[Telemetry|RF telemetry]] has started. First prototype will be tested in a high-altitude balloon in August 2014, in order to validate the RF module and the ground receiver.</div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''May 21, 2012:''''' Boeing [http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_05_21_2012_p25-458597.xml has also announced] its low cost orbital launch system, based on the WhiteKnightTwo carrier craft and a hypersonic air-breathing first and second stages.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''May 21, 2012:''''' Boeing [http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_05_21_2012_p25-458597.xml has also announced] its low cost orbital launch system, based on the WhiteKnightTwo carrier craft and a hypersonic air-breathing first and second stages.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''May 2012:''''' Study is still heavily under way in order to validate our [[Turbofan:Alternative_Designs|alternate turbofan mode of operation]]. This is the first thing to validate before the project can enter a real engine design phase of the engine, which will in turn allow the plane to be designed<del style="font-weight: bold; text-decoration: none;">.</del></div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''May 2012:''''' Study <ins style="font-weight: bold; text-decoration: none;">of aerodynamics </ins>is still heavily under way in order to validate our [[Turbofan:Alternative_Designs|alternate turbofan mode of operation]]. This is the first thing to validate before the project can enter a real engine design phase of the engine, which will in turn allow the plane to be designed.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">'''''February 2012:''''' Study of basic aerodynamics is under way. More man power is expected in April</del>.</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to escape from Earth?==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to escape from Earth?==</div></td></tr>
</table>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=552&oldid=prevVincent: /* News */ balloon update2014-05-04T00:45:00Z<p><span dir="auto"><span class="autocomment">News: </span> balloon update</span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 00:45, 4 May 2014</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2013:''''' CFD has been stalled for a few months. In parallel, work on [[Telemetry|RF telemetry]] has started. First prototype will be tested in a high-altitude balloon <del style="font-weight: bold; text-decoration: none;">during the beginning of </del>2014, in order to validate the RF module and the ground receiver.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2013:''''' CFD has been stalled for a few months. In parallel, work on [[Telemetry|RF telemetry]] has started. First prototype will be tested in a high-altitude balloon <ins style="font-weight: bold; text-decoration: none;">in August </ins>2014, in order to validate the RF module and the ground receiver.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''March 2013:''''' Since December, learning CFD has been the main activity, and it will probably remain so next months. [[CFD:Introduction|A page]] has been created to give CFD beginners some interesting links. CFD has a steep learning curve, but learning how to use it will have huge benefits for the project in the long term:</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''March 2013:''''' Since December, learning CFD has been the main activity, and it will probably remain so next months. [[CFD:Introduction|A page]] has been created to give CFD beginners some interesting links. CFD has a steep learning curve, but learning how to use it will have huge benefits for the project in the long term:</div></td></tr>
</table>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=542&oldid=prevVincent: /* News */ telemetry2013-12-26T01:10:25Z<p><span dir="auto"><span class="autocomment">News: </span> telemetry</span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 01:10, 26 December 2013</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''March 2013:''''' Since <del style="font-weight: bold; text-decoration: none;">december</del>, learning CFD has been the main activity, and it will probably remain so next months. [[CFD:Introduction|A page]] has been created to give CFD beginners some interesting links. CFD has a steep learning curve, but learning how to use it will have huge benefits for the project in the long term:</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">'''''December 2013:''''' CFD has been stalled for a few months. In parallel, work on [[Telemetry|RF telemetry]] has started. First prototype will be tested in a high-altitude balloon during the beginning of 2014, in order to validate the RF module and the ground receiver.</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''March 2013:''''' Since <ins style="font-weight: bold; text-decoration: none;">December</ins>, learning CFD has been the main activity, and it will probably remain so next months. [[CFD:Introduction|A page]] has been created to give CFD beginners some interesting links. CFD has a steep learning curve, but learning how to use it will have huge benefits for the project in the long term:</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* evaluate the lift and drag associated with supersonic wings/fins on the aircraft-launched rocket will enable us to refine the rocket mass ([[File:Rocket_mass.c]]) model</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* evaluate the lift and drag associated with supersonic wings/fins on the aircraft-launched rocket will enable us to refine the rocket mass ([[File:Rocket_mass.c]]) model</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* hopefully have a theoretical validation of our high-altitude turbofan [[Turbofan:Alternative_Designs|alternative design]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* hopefully have a theoretical validation of our high-altitude turbofan [[Turbofan:Alternative_Designs|alternative design]]</div></td></tr>
</table>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=533&oldid=prevVincent: /* The aircraft */ adding price induction turbofan link2013-10-01T00:05:52Z<p><span dir="auto"><span class="autocomment">The aircraft: </span> adding price induction turbofan link</span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 00:05, 1 October 2013</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l66">Line 66:</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Nevertheless, we would benefit from speed of the aircraft, speed that wouldn't be needed by the rocket to reach. It is a low speed compared to orbital speed though. Supersonic launch speed would be nice, but very hard to achieve. Currently, only subsonic speed is considered in the project.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Nevertheless, we would benefit from speed of the aircraft, speed that wouldn't be needed by the rocket to reach. It is a low speed compared to orbital speed though. Supersonic launch speed would be nice, but very hard to achieve. Currently, only subsonic speed is considered in the project.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The major issue with the aircraft is [[Build a cheap turbofan|how to build a £100 turbofan?]] Small turbofan engines exist, but are made for or by the military, so very expensive, very reliable, and their use is restricted to missiles or UAVs. Small gas turbine engines exist however, even in an axial design, see [http://www.bladonjets.com/technology/gas-turbines/ Bladon Jets].</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The major issue with the aircraft is [[Build a cheap turbofan|how to build a £100 turbofan?]] Small turbofan engines exist, but are made for or by the military, so very expensive, very reliable, and their use is restricted to missiles or UAVs. Small gas turbine engines exist however, even in an axial design, see [http://www.bladonjets.com/technology/gas-turbines/ Bladon Jets] <ins style="font-weight: bold; text-decoration: none;">or [http://www.price-induction.com/en/dgen/caracteristiques/ Price Induction] for a commercial turbofan for very small jets (nice picture of the fan [http://www.price-induction.com/site_media/images/dgen-net/technologies/optimisation_de_masse_grand.jpg here])</ins>.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Links on wing or aircraft design related to speed and altitude: [http://forum.avsim.net/topic/328556-u-2-climb-rate/page__st__50#entry1952184].</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Links on wing or aircraft design related to speed and altitude: [http://forum.avsim.net/topic/328556-u-2-climb-rate/page__st__50#entry1952184].</div></td></tr>
</table>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=504&oldid=prevVincent: /* News */ CFD 2013Q12013-03-22T02:08:28Z<p><span dir="auto"><span class="autocomment">News: </span> CFD 2013Q1</span></p>
<table style="background-color: #fff; color: #202122;" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 02:08, 22 March 2013</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2012 <del style="font-weight: bold; text-decoration: none;">update</del>:''''' A simple rocket trajectory model has been made in order to evaluate the trajectory of an aircraft- or balloon-released-rocket. It appears that the Delta V taken for granted for gravity drag for these rockets, around 800 m/s, is quite erroneous, or not possible with the expected overall thrust-to-weight ratio. Without taking into account the aerodynamic effects like lift and drag, for a ratio of around 1.5, the Delta V for gravity drag is at least 1300 m/s. To reduce it, the ratio should be higher, like 3.0, in that case it may be possible to have only 800 m/s Delta V for gravity, but the mass of the engine would be much higher. See [[Rocket:First_approximations#The_gravity_drag_and_overall_thrust-to-weight_ratio_issue|a solution]] to this issue.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">'''''March 2013:''''' Since december, learning CFD has been the main activity, and it will probably remain so next months. [[CFD:Introduction|A page]] has been created to give CFD beginners some interesting links. CFD has a steep learning curve, but learning how to use it will have huge benefits for the project in the long term:</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">* evaluate the lift and drag associated with supersonic wings/fins on the aircraft-launched rocket will enable us to refine the rocket mass ([[File:Rocket_mass.c]]) model</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">* hopefully have a theoretical validation of our high-altitude turbofan [[Turbofan:Alternative_Designs|alternative design]]</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">* simulate different wing profiles at high-altitude subsonic conditions for the carrier aircraft</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">* evaluate aircraft and engine capability on lift-off and early flight conditions while they are both tailored for high altitude flight</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">* refine the heat transfer approximations ([[File:Heat_transfer_to_rocket_tank.c]]) for cryogenics tank vaporization, used in the rocket mass model for tank dimensioning, with a better climb profile input too.</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2012:''''' A simple rocket trajectory model has been made in order to evaluate the trajectory of an aircraft- or balloon-released-rocket. It appears that the Delta V taken for granted for gravity drag for these rockets, around 800 m/s, is quite erroneous, or not possible with the expected overall thrust-to-weight ratio. Without taking into account the aerodynamic effects like lift and drag, for a ratio of around 1.5, the Delta V for gravity drag is at least 1300 m/s. To reduce it, the ratio should be higher, like 3.0, in that case it may be possible to have only 800 m/s Delta V for gravity, but the mass of the engine would be much higher. See [[Rocket:First_approximations#The_gravity_drag_and_overall_thrust-to-weight_ratio_issue|a solution]] to this issue.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The program evaluating the mass of the rocket has been refined (v3), and the forgotten pipe linking the upper tank to the engine adds approximately 150 kg of wet mass too ([[File:Rocket_mass.c]]).</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The program evaluating the mass of the rocket has been refined (v3), and the forgotten pipe linking the upper tank to the engine adds approximately 150 kg of wet mass too ([[File:Rocket_mass.c]]).</div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Incoming works will study aerodynamic lift and drag of a simple rocket and of a rocket with small supersonic wings to better evaluate the gravity drag for our mass evaluation.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Incoming works will study aerodynamic lift and drag of a simple rocket and of a rocket with small supersonic wings to better evaluate the gravity drag for our mass evaluation.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''November 2012 <del style="font-weight: bold; text-decoration: none;">update</del>:''''' Rocket mass [[Rocket:First_approximations#Our_first_approximation|has been estimated]] to 150 kg. Turbofan engines parameters can now be calculated for a real application: aircraft carrier for air-to-orbit single stage rocket, tailored for pico and [https://en.wikipedia.org/wiki/Miniaturized_satellite#Nanosatellite nanosatellites].</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''November 2012:''''' Rocket mass [[Rocket:First_approximations#Our_first_approximation|has been estimated]] to 150 kg. Turbofan engines parameters can now be calculated for a real application: aircraft carrier for air-to-orbit single stage rocket, tailored for pico and [https://en.wikipedia.org/wiki/Miniaturized_satellite#Nanosatellite nanosatellites].</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Also, [[Rocket:First_approximations#Effects_of_parameter_changes|graphs]] have been created to illustrate the importance of various rocket design parameters, such as thrust-to-weight ratios, mass ratio, payload mass. The program ([[File:Rocket_mass.c]]) modelling the mass of rockets is being refined and the cryogenic propellant vaporization has been evaluated by another program ([[File:Heat_transfer_to_rocket_tank.c]]). Both programs are freely available.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Also, [[Rocket:First_approximations#Effects_of_parameter_changes|graphs]] have been created to illustrate the importance of various rocket design parameters, such as thrust-to-weight ratios, mass ratio, payload mass. The program ([[File:Rocket_mass.c]]) modelling the mass of rockets is being refined and the cryogenic propellant vaporization has been evaluated by another program ([[File:Heat_transfer_to_rocket_tank.c]]). Both programs are freely available.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''August 2012 <del style="font-weight: bold; text-decoration: none;">update</del>:''''' A first step in the project realization will be a turbofan's compressor blade manufacturing, in order to validate the manufacturing process suitability and low cost for the turbofan. The first compressor stage prototype has to be designed in this optics. However, that requires having a [[Rocket:First_approximations|first approximation]] of the rocket mass in order to also have an estimation of the aircraft size and mass, from which we can estimate turbofan engine's properties: inlet speed, required thrust, blade length, RPM and so on. Blade manufacturing will mostly rely on a thermocaster that we'll have to design too.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''August 2012:''''' A first step in the project realization will be a turbofan's compressor blade manufacturing, in order to validate the manufacturing process suitability and low cost for the turbofan. The first compressor stage prototype has to be designed in this optics. However, that requires having a [[Rocket:First_approximations|first approximation]] of the rocket mass in order to also have an estimation of the aircraft size and mass, from which we can estimate turbofan engine's properties: inlet speed, required thrust, blade length, RPM and so on. Blade manufacturing will mostly rely on a thermocaster that we'll have to design too.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''May 21, 2012:''''' Boeing [http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_05_21_2012_p25-458597.xml has also announced] its low cost orbital launch system, based on the WhiteKnightTwo carrier craft and a hypersonic air-breathing first and second stages.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''May 21, 2012:''''' Boeing [http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_05_21_2012_p25-458597.xml has also announced] its low cost orbital launch system, based on the WhiteKnightTwo carrier craft and a hypersonic air-breathing first and second stages.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''May 2012 <del style="font-weight: bold; text-decoration: none;">update</del>:''''' Study is still heavily under way in order to validate our [[Turbofan:Alternative_Designs|alternate turbofan mode of operation]]. This is the first thing to validate before the project can enter a real engine design phase of the engine, which will in turn allow the plane to be designed.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''May 2012:''''' Study is still heavily under way in order to validate our [[Turbofan:Alternative_Designs|alternate turbofan mode of operation]]. This is the first thing to validate before the project can enter a real engine design phase of the engine, which will in turn allow the plane to be designed.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''February 2012 <del style="font-weight: bold; text-decoration: none;">update</del>:''''' Study of aerodynamics is under way. More man power is expected in April.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''February 2012:''''' Study of <ins style="font-weight: bold; text-decoration: none;">basic </ins>aerodynamics is under way. More man power is expected in April.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to escape from Earth?==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to escape from Earth?==</div></td></tr>
</table>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=494&oldid=prevVincent: /* The aircraft */ Bladon link2013-01-11T00:46:29Z<p><span dir="auto"><span class="autocomment">The aircraft: </span> Bladon link</span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 00:46, 11 January 2013</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==The aircraft==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==The aircraft==</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Some aircraft have been exploring the high atmosphere, around 30km high. Contrary to what one would assume, high flight speeds are not needed, if the weight is kept low. The [http://www.nasa.gov/centers/dryden/news/ResearchUpdate/Helios/index.html Helios] for example, autonomous solar powered aircraft, flights at this altitude at 20km/h. John Powell [http://www.jpaerospace.com/] is also researching on high altitude propellers and plans to make it to space using a high altitude base for payload transfer to a bigger plane. He describes it well in this [http://www.youtube.com/watch?v=G7LQuVfDwFQ video] interview. The [https://en.wikipedia.org/wiki/Lockheed_U-2 U-2] is a manned reconnaissance aircraft flying at 21km altitude, cruising at relatively high speeds (690km/h). Those planes are designed with a very long wingspan, and low weight, similar to gliders.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Some aircraft have been exploring the high atmosphere, around 30km high. Contrary to what one would assume, high flight speeds are not needed, if the weight is kept low. The [http://www.nasa.gov/centers/dryden/news/ResearchUpdate/Helios/index.html Helios] for example, autonomous solar powered aircraft, flights at this altitude at 20km/h. John Powell <ins style="font-weight: bold; text-decoration: none;">(</ins>[http://www.jpaerospace.com/ <ins style="font-weight: bold; text-decoration: none;">JP Aeroospace</ins>]<ins style="font-weight: bold; text-decoration: none;">) </ins>is also researching on high altitude propellers and plans to make it to space using a high altitude base for payload transfer to a bigger plane. He describes it well in this [http://www.youtube.com/watch?v=G7LQuVfDwFQ video] interview. The [https://en.wikipedia.org/wiki/Lockheed_U-2 U-2] is a manned reconnaissance aircraft flying at 21km altitude, cruising at relatively high speeds (690km/h). Those planes are designed with a very long wingspan, and low weight, similar to gliders.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Another kind of design is the fighter jet, for example the [https://en.wikipedia.org/wiki/Mig_25 MiG-25] which also was an altitude (amongst other) record breaker. It had two powerful turbojet engines with afterburner, allowing him to reach a service altitude of 20km and a maximum altitude of more than 37km. It however required a thrust (200kN) <del style="font-weight: bold; text-decoration: none;">nearly </del>equivalent to the empty weight of the plane <del style="font-weight: bold; text-decoration: none;">(20,000kg) </del>and large amounts of fuel to climb this high. The same is true for the [https://en.wikipedia.org/wiki/Sr-71 SR-71].</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Another kind of design is the fighter jet, for example the [https://en.wikipedia.org/wiki/Mig_25 MiG-25] which also was an altitude (amongst other) record breaker. It had two powerful turbojet engines with afterburner, allowing him to reach a service altitude of 20km and a maximum altitude of more than 37km. It however required a thrust (200kN) equivalent to the empty weight of the plane and large amounts of fuel to climb this high. The same is true for the [https://en.wikipedia.org/wiki/Sr-71 SR-71].</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>These concerns of how high altitude is reached - mainly through high engine power or high lift at subsonic flight - is discussed on the page dedicated to [[Flight at high altitude|high altitude flight]]. Currently, the subsonic way is being studied, both for rocket and the aircraft, since a higher release velocity means that the rocket can be smaller, and consequently the plane too.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>These concerns of how high altitude is reached - mainly through high engine power or high lift at subsonic flight - is discussed on the page dedicated to [[Flight at high altitude|high altitude flight]]. Currently, the subsonic way is being studied, both for rocket and the aircraft, since a higher release velocity means that the rocket can be smaller, and consequently the plane too.</div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Nevertheless, we would benefit from speed of the aircraft, speed that wouldn't be needed by the rocket to reach. It is a low speed compared to orbital speed though. Supersonic launch speed would be nice, but very hard to achieve. Currently, only subsonic speed is considered in the project.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Nevertheless, we would benefit from speed of the aircraft, speed that wouldn't be needed by the rocket to reach. It is a low speed compared to orbital speed though. Supersonic launch speed would be nice, but very hard to achieve. Currently, only subsonic speed is considered in the project.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The major issue with the aircraft is [[Build a cheap turbofan|how to build a £100 turbofan?]] Small turbofan engines exist, but are made for or by the military, so very expensive, very reliable, and their use is restricted to missiles or UAVs.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The major issue with the aircraft is [[Build a cheap turbofan|how to build a £100 turbofan?]] Small turbofan engines exist, but are made for or by the military, so very expensive, very reliable, and their use is restricted to missiles or UAVs<ins style="font-weight: bold; text-decoration: none;">. Small gas turbine engines exist however, even in an axial design, see [http://www.bladonjets.com/technology/gas-turbines/ Bladon Jets]</ins>.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Links on wing or aircraft design related to speed and altitude: [http://forum.avsim.net/topic/328556-u-2-climb-rate/page__st__50#entry1952184].</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Links on wing or aircraft design related to speed and altitude: [http://forum.avsim.net/topic/328556-u-2-climb-rate/page__st__50#entry1952184].</div></td></tr>
</table>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=485&oldid=prevVincent: text updates, more links, more fixes2012-12-29T01:43:20Z<p>text updates, more links, more fixes</p>
<a href="https://lcas.otaski.org/index.php?title=Main_Page&diff=485&oldid=463">Show changes</a>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=463&oldid=prevVincent: /* News */ about the gravity drag issue2012-12-12T15:46:47Z<p><span dir="auto"><span class="autocomment">News: </span> about the gravity drag issue</span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:46, 12 December 2012</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2012 update:''''' A simple rocket trajectory model has been made in order to evaluate the trajectory of an aircraft- or balloon-released-rocket. It appears that the Delta V taken for granted for gravity drag for these rockets, around 800 m/s, is quite erroneous, or not possible with the expected overall thrust-to-weight ratio. Without taking into account the aerodynamic effects like lift and drag, for a ratio of around 1.5, the Delta V for gravity drag is at least 1300 m/s. To reduce it, the ratio should be higher, like 3.0, in that case it may be possible to have only 800 m/s Delta V for gravity, but the mass of the engine would be much higher<del style="font-weight: bold; text-decoration: none;">, and the rocket is estimated </del>to <del style="font-weight: bold; text-decoration: none;">be at least 150kg more</del>. The program evaluating the mass of the rocket has been refined, and <del style="font-weight: bold; text-decoration: none;">adding </del>the forgotten pipe linking the upper tank to the engine <del style="font-weight: bold; text-decoration: none;">add </del>approximately <del style="font-weight: bold; text-decoration: none;">100 </del>kg of wet mass too..<del style="font-weight: bold; text-decoration: none;">. </del>Incoming works will focus on how much we can expect the aerodynamic lift to compensate the gravity drag, and how much we can reduce the engine's thrust to decrease the mass of the vehicle while staying air-SSTO.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>'''''December 2012 update:''''' A simple rocket trajectory model has been made in order to evaluate the trajectory of an aircraft- or balloon-released-rocket. It appears that the Delta V taken for granted for gravity drag for these rockets, around 800 m/s, is quite erroneous, or not possible with the expected overall thrust-to-weight ratio. Without taking into account the aerodynamic effects like lift and drag, for a ratio of around 1.5, the Delta V for gravity drag is at least 1300 m/s. To reduce it, the ratio should be higher, like 3.0, in that case it may be possible to have only 800 m/s Delta V for gravity, but the mass of the engine would be much higher<ins style="font-weight: bold; text-decoration: none;">. See [[Rocket:First_approximations#The_gravity_drag_and_overall_thrust-to-weight_ratio_issue|a solution]] </ins>to <ins style="font-weight: bold; text-decoration: none;">this issue</ins>.</div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The program evaluating the mass of the rocket has been refined <ins style="font-weight: bold; text-decoration: none;">(v3)</ins>, and the forgotten pipe linking the upper tank to the engine <ins style="font-weight: bold; text-decoration: none;">adds </ins>approximately <ins style="font-weight: bold; text-decoration: none;">150 </ins>kg of wet mass too <ins style="font-weight: bold; text-decoration: none;">([[File:Rocket_mass</ins>.<ins style="font-weight: bold; text-decoration: none;">c]])</ins>.</div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Incoming works will focus on how much we can expect the aerodynamic lift to compensate the gravity drag, and how much we can reduce the engine's thrust to decrease the mass of the vehicle while staying air-SSTO.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''November 2012 update:''''' Rocket mass [[Rocket:First_approximations#Our_first_approximation|has been estimated]] to 150 kg. Turbofan engines parameters can now be calculated for a real application: aircraft carrier for air-to-orbit single stage rocket, tailored for pico and [https://en.wikipedia.org/wiki/Miniaturized_satellite#Nanosatellite nanosatellites].</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''November 2012 update:''''' Rocket mass [[Rocket:First_approximations#Our_first_approximation|has been estimated]] to 150 kg. Turbofan engines parameters can now be calculated for a real application: aircraft carrier for air-to-orbit single stage rocket, tailored for pico and [https://en.wikipedia.org/wiki/Miniaturized_satellite#Nanosatellite nanosatellites].</div></td></tr>
</table>Vincenthttps://lcas.otaski.org/index.php?title=Main_Page&diff=440&oldid=prevVincent: /* News */ updates for the erroneous gravity drag and thrust2012-12-02T01:16:07Z<p><span dir="auto"><span class="autocomment">News: </span> updates for the erroneous gravity drag and thrust</span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 01:16, 2 December 2012</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>''News are also available on twitter [https://twitter.com/OTASKI @OTASKI]''</div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">'''''December 2012 update:''''' A simple rocket trajectory model has been made in order to evaluate the trajectory of an aircraft- or balloon-released-rocket. It appears that the Delta V taken for granted for gravity drag for these rockets, around 800 m/s, is quite erroneous, or not possible with the expected overall thrust-to-weight ratio. Without taking into account the aerodynamic effects like lift and drag, for a ratio of around 1.5, the Delta V for gravity drag is at least 1300 m/s. To reduce it, the ratio should be higher, like 3.0, in that case it may be possible to have only 800 m/s Delta V for gravity, but the mass of the engine would be much higher, and the rocket is estimated to be at least 150kg more. The program evaluating the mass of the rocket has been refined, and adding the forgotten pipe linking the upper tank to the engine add approximately 100 kg of wet mass too... Incoming works will focus on how much we can expect the aerodynamic lift to compensate the gravity drag, and how much we can reduce the engine's thrust to decrease the mass of the vehicle while staying air-SSTO.</ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''November 2012 update:''''' Rocket mass [[Rocket:First_approximations#Our_first_approximation|has been estimated]] to 150 kg. Turbofan engines parameters can now be calculated for a real application: aircraft carrier for air-to-orbit single stage rocket, tailored for pico and [https://en.wikipedia.org/wiki/Miniaturized_satellite#Nanosatellite nanosatellites].</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''''November 2012 update:''''' Rocket mass [[Rocket:First_approximations#Our_first_approximation|has been estimated]] to 150 kg. Turbofan engines parameters can now be calculated for a real application: aircraft carrier for air-to-orbit single stage rocket, tailored for pico and [https://en.wikipedia.org/wiki/Miniaturized_satellite#Nanosatellite nanosatellites].</div></td></tr>
</table>Vincent