Scarecrow

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About Scarecrow

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  1. For anyone looking for a reuseable vehicle to launch a small number of satellites in to orbit, this may be the craft for you. This vehicle comes with a ready fitted payload of 3 communication satellites that are able to reach 500km orbits and way beyond. They may require several burns and a recovery period for the batteries to recharge, but there is plenty of fuel on board each satellite to reach orbits way in excess of 500km. Due to the asymmetric thrust and offset centre of mass that is inherent in the design, flying this vehicle to orbit is probably not advised for newcomers to KSP but, having said that, if you can follow the flight profile I have developed you shouldn't have any problems. Pilot notes Due to the general low thrust to weight ratio, this vehicle needs a steeper launch ascent profile than normal At launch, turn on SAS and set throttle to full. Stage to launch and then sit back for a bit. When the solid boosters run out of fuel, stage to jettison them. Don't start the gravity turn too soon but aim to have the nose pointing at 45 degrees above the horizon by about 30000m and before the external tank runs out of fuel. When the external tank runs out of fuel DO NOT STAGE TO JETTISON. It is important you use AG key 1 to jettison the tank as this also changes the thrust on the engines to prevent an uncontrolled pitch Once the external tank is clear, put the nose on the prograde marker. When your Apo reaches 150km, shut the throttle, coast to Apo and then burn to circularise. Try not to push your orbit above 150km otherwise the shuttle will be short on fuel for de-orbiting. To release the satellites, AG key 5 will toggle the cargo doors, then AG keys 7, 8 and 9 will release the satellites in the right sequence. Use the [ ] keys to switch to the satellites as they are released and use AG key 3 to extend the antenna Right click the engine on the satellite and activate it, then burn to the required orbit altitude. When all satellites have been deployed, close the cargo doors. A de-orbit burn above the desert on the continent to the west of KSC with a predicted touch down in the sea a short distance to the east of KSC should see you set for a runway landing. AG key 3 will toggle the airbrakes if they are required. Action Group key summary 1 : Jettison external tank 3 : Extend satellite antenna / toggle shuttle airbrake 5 : Toggle cargo bay doors 7 : Deploy 1st satellite 8 : Deploy 2nd satellite 9 : Deploy 3rd satellite The craft file can be downloaded from Dropbox : https://www.dropbox.com/s/yiytlt50fhj1pw4/Comms Shuttle.craft?dl=0
  2. Scarecrow

    Duna ship with rovers

    This ship is designed for Duna exploration. The lander has two rovers for exploring the surface. Fuel in each stage is generous for the tasks each stage is designed for. Craft download and flight profile notes can be found at KerbalX
  3. Scarecrow

    Help me escape the atmosphere

    I just put two instruments on the capsule to emulate the extra payload on the OP's craft, as I couldn't quite make out exactly what he had used. I agree that if you are going to light the main engine at the same time as the boosters then you will need to reduce the thrust of the boosters as the boosters alone have plenty of thrust for the initial part of the launch, and lighting all three engines at full thrust together would be overkill.
  4. Scarecrow

    Help me escape the atmosphere

    For the OP, if my explanation of what I eventually did to your craft is a bit confusing, this is what the final version looks like.
  5. Scarecrow

    Help me escape the atmosphere

    I built a duplicate rocket to yours as best I could from the image you posted. I couldn't quite make out what scientific instruments you have attached to the capsule, but performance figures are very similar. As built, I found that there was insufficient control to make an adequate gravity turn, which meant that all of the initial burn was spent going almost straight up. After the solid boosters were jettisoned, I subsequently struggled to build up sufficient horizontal velocity to achieve orbit. I made 2 changes, and was able to do a Mun flyby with fuel to spare. The first change was to swap the fins you have for AV-R8 winglets, which are steerable. A gravity turn will have you heading at 45 degrees from vertical by the time you reach 10,000m, give or take. The winglets will allow you to achieve that. The second change I made was to move one of the FL-T400 tanks from the upper stage to the lifting stage. Whilst this reduced the overall dV of the vehicle slightly, it has 2 benefits. It allows the engine on your lifting stage to burn for longer. I was able to achieve an 80km orbit with this stage with a small amount of fuel remaining. The second benefit is that it improves the TWR of your upper stage, giving shorter burn times. The vehicle, as amended, was perfectly capable of doing a Mun fly by. I did a free return trajectory, making a correction burn on the way back to drop my Pe in to the atmosphere of Kerbin. The upper stage still has way more fuel than is actually required. In fact, just to prove that it is actually carrying too much, in a second flight I removed the FL-T200 tank from the upper stage. This improved the TWR of all stages of the vehicle, and actually allowed me to achieve an 80km orbit with 600 m/s dV left in the lifting stage, which is almost enough to reach the Mun. Adding to what @OhioBob said, it is possible to achieve your Mun flyby with even less. To show that lighter and smaller can often be better, I further modified your craft - removing one of the FL-T400 tanks from the lower stage and one of the SRBs. To maintain symmetry, I increased the number of fins from 3 to 4. In this configuration the vehicle is capable of reaching an 80km orbit with just the smallest amount of fuel left, and the upper stage still has over 2000 m/s dV, which is more than enough to get to the Mun and back.
  6. Scarecrow

    SSTOs! Post your pictures here~

    This is my latest SSTO. Designed to perform the simple function of transferring crew to and from my LKO station.
  7. Scarecrow

    I need help...

    Wet spaghetti spaceships in KSP has always been one of my bugbears. Lots of people have commented that it's a feature of the game, that you just need to build right or add more struts. Personally, I just think it's a pain in the nether regions. My solution to the wobbling problem is to install a mod called Kerbal Joint Reinforcement. Problem solved. https://forum.kerbalspaceprogram.com/index.php?/topic/50911-13-kerbal-joint-reinforcement-v333-72417/
  8. Scarecrow

    My aircraft's 100th download on KerbalX

    My submarine link UB-40
  9. Scarecrow

    My aircraft's 100th download on KerbalX

    Strangely my most downloaded craft on KerbalX is actually a submarine. Go figure.
  10. Scarecrow

    putting images on kerbalx

    Upload your images to somewhere like imgur or flickr and then link to them in KerbalX.
  11. Scarecrow

    SSTO Crew Transfer

    On that SSTO there is a drag chute attached normally just below the tail fin. On my Apollo style capsules, I tend to attach 3 radial chutes to a small girder or beam, which itself is attached to the top of the capsule. I then use the offset tool to lower the girder so that it is out of sight, and allowing me to attach the escape tower to the top of the capsule.
  12. Scarecrow

    SSTO Crew Transfer

    What @qzgy said.
  13. Scarecrow

    SSTO Crew Transfer

    This was designed for transferring exchange crew to and from my stations in LKO. It has a capacity of 8 Kerbals and can be used for servicing stations up to a 250km orbit. Action group keys are : 1 - Toggle engine mode 3 - Toggle airbrakes 5 - Toggle the docking port and cargo bay doors Download craft file from KerbalX
  14. Scarecrow

    Best time to rendezvous?

    If you find that you are doing long burns to make rendezvous then I would suggest that you are doing something wrong. Even if you find yourself on the opposite side of the planet to your target it only requires patience and a few orbits before they are much closer. No need to do any burning.
  15. Scarecrow

    The Dessert Derby 2018

    Damn. I came here expecting to find a Knickerbocker Glory eating contest and all I found was a race across some desert.