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Cygnus Recoverable SSTO Rockets family I'm happy to present you the Cygnus recoverable SSTO rocket family. Those rockets are designed to be a cost efficient way to orbit payload (from 15 tons to 300 tons) to LKO. Their mass efficiency ranges from 15% to 19%. Then you can deorbit them, reenter Kerbin atmosphere and make a slightly powered landing as near as KSC as possible to maximize cost return. You can easily get around 95% of the dry cost of the launcher. (all picture are clickable) Cygnus Package Download package : Test crafts and sub-assemblies (160kB) This file contains: 11 launch stage sub-assemblies 11 test rockets craft General flying (1.0.4) Ascent profile Don't activate SAS at take-off. Start gravity turn when speed is 40m/s. You should get to 45° at 8km. You may experience sliding during ascent : try to compensate or activate SAS. Orbit insertion burn should be from 300 to 600m/s. Wobbling payloads can wreck ascent. I suggest you use the "Kerbal Joints Reinforcement" mod created by Ferram4. In space You should have 100 to 200m/s left before detaching the payload When on stable orbit, detach payload and stay on the SSTO stage. You should have a comfortable 200 to 500m/s of dV left for reentry. As the stage doesn't have any power generation, it will run out of power in few orbits. Reentry I suggest a 60m/s deorbit on the west border of the crater (90° west of KSC). This means you would slighly overshoot KSC (70km) Follow retrograge if you want. Deploy airbrakes as soon as possible. If you forget, you'll destroy your chutes later and crash. Drogue chutes and regular chutes are configured to autodeploy at safe altitude (if you deploy airbrakes). Stage them as soon as possible (even in space) If you overshoot a lot, you can burn fuel, but keep at least 100m/s for powered landing. If you're too short, you can close airbrakes, but that's dangerous : you may not slow down enough to open you chutes safely. Drogues should deploy at 8km/5km (500m/s) and regular should open at 3km/800m (250m/s) At 100m, enable SAS to reduce rocket flip in water. Landing are powered : under 75m, tap "shift" once or twice to slow down around 5m/s. On touchdown or splashdown, keep SAS on and recover the stage as soon as possible. Don't let the rocket flip in water or fall on ground, that will break some expensive parts. Specifics Cygnus RR-015 can be landed without firing the engine. Beware of flipping though Cygnus RR-032 and RR-100 don't have double symmetry. If you want to use them on a non eastward ascent, rotate the rocket. Cygnus RR-015, RR-032 and RR-100 will probably flip when landed, Don't delay the vessel recovery. Cygnus RR-075 has an additional skipper which is used only during the first ascent. It shuts down quickly by design. Cygnus RR-125 don't use fuel conduits. The lateral engines will shutdown quicker than the central one. Beware of loosing power at landing Design usage All Cygnus SSTO stages come with a test craft and sub-assembly. The test crafts have a dead payload of the max weight of each stage. Rocket designation : Cygnus RR rocket identification is it's maximum payload Techlevel is quite high, especially because of large probe core and battery. Don't hesitate to remove the adapter and decoupler to use a bigger one. Also, add the fairing to the SSTO stage if needed. Heat shield is designed for LKO reentry, it's half full on purpose. If you have a lighter weight, I suggest reducing the engine thrust to match rocket TWR. To reduce cost, you can remove some fuel tanks. As a rule of thumb 3400m/s is sufficient to ascent properly with some comfortable margin to deorbit and partially powered landing with a TWR from 1.35 to 1.5 (tested). If payload makes your rocket flip, change bottom wings to bigger ones. Also, try reducing speed between 5km and 20km. No part clipping. 4 winglets can be added somewhere under parachutes, but I've noticed they aren't that useful. They will probably blow during reentry. Specifications RR-015, RR-032 and RR-050 RR-075, RR-100 and RR-125 RR-150, RR-200 and RR-300 RR-400, RR-600 Feedback appreciated.