For the non direct HTO intercept challenge the negative Delta Velocity presents some challenges that I've experienced thus far. It seems one low earth orbits for take off present altitude control issues. One I'd mention that a negative delta is an added velocity to already an already negative orbital rotation. I'd mention negative rotation in the sense being non positive relative Earth's orbital rotation (meaning your ship is moving in the opposite direction of Earth's rotation). First if you haven't experienced low altitude negative orbital rotation, you may find that the effects of angular momentum as I did in a couple test case examples on Mars. The effect of this is the craft at low angular velocities spinning in my case in a nearly geostationary fashion (when attempting re entry), or at least this could be seen as rotation around a geostationary point. Thus, in my case, successful cases of delta v were applied at much higher earth orbits > 5 million km. Still running at 5 M km I did experience as in one test case crash and burn in the case of lower -delta v improperly maintaining altitude even while maintaining periapsis altitude well above Earth's altitude. Secondly even while burning at proper TrL (this is the position for ejection point) for you delta V burn. I found that the possible change to periapsis will effect the shape of your elliptic trajectory. Ideally your periapsis point should be positioned as close to TrL as possible...thus the challenge of balance both altitude loss changing from positive to negative retrograde motion and then maintaining periapsis at the position of TrL ejection. Some additional food for thought on the aspect of interplanetary elliptic are as follows, keep in mind that while your TAS may read a given velocity for a celestial object set to default Earth, this is including Earth's relative angular motion. For interplanetary journeys to the inner solar system, your elliptic should be smaller then Earth's angular rotation, this means that you are subtracting instantaneous velocity at ejection from your craft's already existing Angular rotation at Earth's angular rotation around the sun. Aside from the Transfer MFD which shows the necessary for inner solar system journey, I also recommend setting your Orbit MFD referencing the Sun, and then selecting your target 'Venus'. Once engaged in the ejection at some point your elliptic ejection will be graphically shown visually similar to the graphic shown for the Transfer ejection graphic. Keep in mind, because you are still rotating around the Earth, this trajectory calculation on the Orbit MFD may change owing to any flyby relative to Earth...I recommend running your simulator at 1000 times greater until you've reached say 100 M km or greater from Earth where ideally your trajectory should be represented in more stable orientation. I've also encountered another problem with HTO calculations for Transfers where at the given Ejection date my planet's estimated position having jump changed from its intended calculation. Sort of unfortunate since this could make more problematic future planning. My work around is simply having the craft in proper orbit and aligned on plane and simply setting the ejection date slightly elapsed to verify position, fortunately it seems by adjusting DV I could find an intercept at some position.
When you run the burn its important to keep in mind that Earth is rotating around the sun at 108,000 km /h relative the Sun, even though your delta v shown in the opposite direction relative Earth's rotation and seemingly in the opposite direction when departing at ejection point, your craft is still moving in counter clockwise positive angular motion relative the sun. Basically your craft moves on an inner elliptic relative Earth's past the sun, gaining instantaneous velocity as it nears the sun and the slingshot's toward Venus on the opposite side of the elliptic (relative start). Venus instantaneous average angular velocity is approximately 20,030 km/h and while technically Venus is one of the only planet's whose orbital motion in clockwise in the Solar system relative all other planets. Technically the linear speed differential between the two planets is in the order of roughly 128,000 km/h here, or in other words, if physics of orbital motion weren't applied here to our advantage, we might have otherwise a lot of braking energy applied getting from one planet to the other!
Some fun unlimited fuel challenges are matching the orbital elliptic of Venus's by running burns on Apoapsis and Periapsis to achieve a similar orbit to Venus's. You can do this by procedure using the Orbit MFD settings mentioned above. If you wanted to do this on the quick, you can use your Lua Console to set your MJD date to near both burn points, otherwise, you'll be in for much longer real time waits even at higher given sim rate options. Function control for this is oapi.set_simmjd(MJD) where MJD is your input time format in Julian date format.
Will likely set a much higher altitude at 10M km from Earth for negative ejection burn here. This should provide more efficiency and altitude stability on the negative delta v ejection burn. As a reminder the ejection burn I believe means running a negative velocity (relative to an existing positive retrograde motion) whose orbital velocity is equal and opposite at such altitude (and then adjusting for altitude loss) and then applying delta v. This means the total ejection I believe if altitude is maintained stable at 2 x (existing TAS...burning off retrograde motion to turn to negative retrograde motion which will flip on your TAS indicator) plus your negative DV. Altitude loss will typically add some to your necessary formulation since higher instantaneous velocities are typified at lower altitudes, and thus change change the nature of your elliptic. Another possible solution that I've considered studying here in the unlimited fuel case (likely not as great a solution since you are working on more fuel burns), is creating an inner solar system elliptic, then burning at perihelion (periapsis relative the sun) so that your elliptic is less then Venus. Running the Transfer MFD and searching intercepts and running running a prograde burn at the right ejection point on the inner elliptic (relative Venus's).
Update:
Ran a successful mission with some caveats. First, I highly recommend a high altitude Earth orbit in my case 10.5M km. While in terms of periodicity of the higher oribt means more sim time waiting there are a couple of aspects that I liked for this ejection setup: less altitude loss, and less fuel spent/burn time spent in reaching negative delta v ejection. The first round elliptic appeared to be fruitless for tracking and subsequent orbits would take longer time lengths for in terms of a lengthier periodicity. Instead I modified my approach track doing the following. I burned retrograde at perihelion to run a smaller radial elliptic relative Venus's orbital elliptic. From this point, my craft's periodicity on the elliptic being different would translate into more optimal intersections relative the Venus's elliptic path...my shuttle were generally moving with differences in angular velocity because of a greater then 0 eccentricity of my Sun relative orbital track and being non matched to Venus's sun relative orbital eccentricity. This were a little bit of a go round the merri go round track. Basically to achieve this I used the the Transfer MFD at several places performing a combination of prograde and retrograde burns. The burns themselves were surprising short (a modest less then 2 k burn in most cases). The bigger burn were the perihelion retrograde burn (more likely no more then a 10 k burn on earth for ejection) to an inner elliptic path relative Venus's. While I did perform some initial manual course correction burns on the final approach (very modest relative Venus speeds a little above 2k TAS). I like this approach the best since it seemed there were greater opportunities for fuel economy use while providing many opportunities for the approach even if something went wrong. The biggest burn generally were the Earth based ejection point overall. I liked this especially so because my approach track relative Venus started at a very modest 2.2 k venus relative TAS. And the fuel spent for orbital capture on the periapsis retrograde burn ended at 7k TAS Venus relative. My overall sim time on this trip started 52192 and ended 52624 or 432 elapsed modified Julian days.
Step by Step:
1. Starting on the ground at Earth. Pull up your Transfer MFD (Press SEL next to MNU just below the MFD console). Set Ref to 'Sun' (once pressing the REF button a little menu appears, you can press Enter as Sun is default), Source to 'Earth' (when the menu appears for selection press your arrow keys up or down to select your given planet), and TGT to 'Venus'. Press HTO to engage the intersections search. Next Adjust your by pressing holding your DV- button until the dashed green line intersects the inner yellow ellipse representing Venus's orbit. Here you can rotate positive or negative the Ejection window by pressing the EJ- or EJ+ buttons and holding this. You will need to align the gray line with the dashed yellow line. If no intersection appear at the given launch DV you can make adjustments to your DV- or DV+ as needed while maintaining the intersection at least two points the dashed green yellow ellipse with the solid yellow line. If no ejection DV appears to suffice for intercept at this ejection position, then you will need to adjust your Ejection position pressing the EJ+ or EJ- buttons. If the the launch date is in the the first three quadrants < 270 degrees from your present position. I recommend using the Lua consolej and using oapi.set_simmjd(MJD) to change your Earth relative position so that you are slightly elapsed on the launch window. While its not 365 MJD exactly per year for Earth's orbital rotation, this provides you a rough estimator for setting MJD dates...simple add days to your existing MJD date. I do this in integer formats which works fine. Once having found a suitable intersection. I've also found setting the Ejection time slightly elapsed basically Earth's position is just slightly greater then (< 180 degrees for earth's position ) or slightly less then (> 180 degrees for Earth's position). Then adjust your DV either adding or subtracting DV as indicated above while maintaining intersection of your dashed green line with the solid yellow line (at two points). The reason for this is that actual predicted position of the planet relative time elapsed for your craft's motion seems to be more accurate doing this.
Once a suitable ejection time is found and you are at or slightly elapsed to launch time, you can now launch.
2. Go ahead and set on the alternate window your Orbit MFD set the REF to 'Earth', and set TGT to 'Venus'. Press PRJ on your Orbit MFD until this shows Frm ECL Prj SHP. Make sure your PeA (periapsis) and ApA (apoapsis) values are in km as opposed to radians, you can easily see this by the k for km designation or M for radians designations. Its easy for me to see relations of altitude in km unless you understand the relation of radians to altitude, you can change to radians or km respectively by pressing the DST button on the Orbit MFD console. Its important to note when you climb the PeA value later. So keep this in mind.
3. Press the HUD button on your Orbit MFD console. This ensures your TAS (Green Hud indicators are set for Earth relative readings).
4. Presuming you understand basic flight maneuvering. Make sure your Surface HUD is engaged. If you are on a standing launch pad, use the hover button, increasing this positive until you have flight lift. Next, once at 1k in altitude engage throttle full for speed. Disengage your Hoover speed, and lift your gear. Increase your altitude pitching the nose up generally at around 60 degrees, generally speaking anywhere between 40 and 60 degrees seems fine, the climb is slow at lower pitches. Once you climb to above 50 km you will begin to notice change in your crafts aerodynamic lift. At 75km altitude I recommend engaging your Orbit HUD using the button in the upper left of your console. At this point if handling become difficult you can stabilize your craft using the Kill Rotation button.
5. We will be achieving a high Earth orbit altitude here at 10M km, so the climb will take some time here. I recommend that you craft is stably maintained oriented such that your craft is climbing away from Earth, you can note this by your Orbit MFD s PeA value as this inclines further and further until showing 10 M km, you will likely need to disengage your engines, but first you will want to make note of your crafts speed. You will need to be flying at around 4k on your TAS for stable orbit, mostly you want to make sure your craft is moving in positive motion reasonably at least within 2 or 3 k TAS prior to reaching PeA. You can fast forward your simulator using the Speed simulator functions, I recommend stepping this up no more then a 1000 times, generally though here I don't recommend this initially using this above 100 times especially on the first PeA ascent.
6. Press the Prograde button (upper right of your ship's console). This should be lit engaged.
7. Make note of your ApA and PeA values.
8. Once ApA and ApT have elapsed to zero. You will need to fire your engine thrusters until Ecc is nearly close to zero (don't worry if its slightly off). If you need to increase your ship's overall altitude you can fire in Prograde position your thrusters once your ship is positioned to ApA and PeA separately. You will want to make note of the Ecc value on your Orbit MFD when running a burn. If you want to decrease altitude you do the same as except making sure that your ship is in Retrograde position (pressing the Retrograde button and making sure this is lit).
Now's a good time to do a quick save, so that you can always restart your scenario if you like.
Let's align the ship to Venus's orbital plane.
9. Press SEL (just below the MFD console) on your existing Orbit MFD.
10. Select the Align Planes MFD.
11. Once your ship on the rotation plane is at or near AN your ship will need will need to be in the Orbit-Normal (-) position, while being in the opposite position (Orbit-Normal (+)) when on or near the DN position . You can speed your simulator up by 10 or 100 times you can see what position is moving towards here. Once determining the position that you are headed towards. Set your ship into the given Orbit normal position as necessary well in advance.
12. Follow the instructions on the Align Planes MFD when it says "Kill Thrust" make sure to kill your thrust. Your Rinc value should decline as you burn, and this should close to zero (don't worry if its not exactly zero).
13. Press SEL just below your Align Planes MFD, and select the Orbit MFD again. By default this should have your Earth orbit settings.
14. This point on your Transfer MFD, I will assume your DTe has elapsed. Earth's position Shown solid green should appear at or near the dashed green window ejection. Procedurally you can use the Lua Console for time acceleration...keep in mind 100k time translates into approximately 1 day of time...
15. Position your ship in Retrograde. Initially when you fire I recommend your celestial bodies view is engaged. Visually I make note of this since HUD oribtal readouts will change as you burn on ejection. Generally I work to fire the ship maintaining orientation at the constellation group that I originally fired in orientation pointing towards.
16. Make note of TrL values on your Transfer MFD. This will be the point at which you fire engines to engage ejection. On your close approach to the TrL value, you will want to make note of your TAS value (this is your Earth orbit relative speed). You will need to add this value to the negative DV shown on your transfer MFD. Your actual TrL position is given on your Orbit MFD. Once your TrL elapses fire engines.
17. Hit the Kill rotation button on your ship, and maintain orientation on the constellation group that you are at. It doesn't need to be perfect, but you can hit as necessary the Kill Rotation button to maintain your crafts altitude. There are two parts to the ejection: zeroing out your velocity, and increase your ship's velocity that you computed in step 16 (this is negative orbital plus delta v ejection). I've added a slight amount of orbital velocity for slight loses in altitude (although I didn't formal compute the precise negative orbital value needed here)...my addition were in the range of 20 on TAS. My altitude restabilized at around 9.6M km, so don't worry if you have lost some altitude.
18. Once reaching the desired ejection velocity. Kill thrust. We'll set up your Orbit MFD for a new reference.
19. Change REF to 'Sun', change TGT to 'Venus'. Here you will note at this point the relation of your Orbit MFD of your ship's trajectory being roughly similar to the projected orbital trajectory shown in your Transfer MFD. Don't worry if the shape is rough here, it will change and stabilize over time as you move upon distance gained moving away from Earth. At 250 M km out (from Earth), this should begin to assume generally the shape and form shown in your Transfer MFD, but no worries even if you are off, other things can be done.
20. Since there is a lot of simulation time involved in this. I personally like to run simulation ahead in steps of 25, 50, 100 days to see how close projections are availed here. At some point if it appears the position of the planet for whatever reasons is unlikely to be at the the projected position (or remotely near it). I've set up a new approach procedure. If it appears that your trajectory is way off on the intercept to Venus's position move to the alternate approach track shown below.
The alternate procedure
You can use the Lua console to move forwards or backwards in time as indicated using the oapi function mentioned above. Move to within approximately no more then several hundred k seconds, and then you can manually adjust on the decimal MJD with function to reduce time to near or less then 100k from relative to PeT. Within 100k I run sim time using the menu speed controls.
21. Do a retrograde burn PeT, PeA shown on your Orbit MFD. The burn need not occur to the extent of modifying your trajectory to zero Ecc, but fitting this trajectory to fit on or inside Venus's orbital path.
22. Reconfigure your Transfer MFD Source, by Pressing SRC then typing 'GL-01' if you using the glider or your craft's code handle and pressing enter.
23. You will use the same procedure as in Step 1 above except you will need a positive delta v burn. If you don't see good alignments here. I recommend cycling time forward say by increments of 25 days and rechecking as actual planet to ship positions will provide new transfer possibilities. At some point you will find a good transfer opportunity.
Once you are within 5 or 6 G distances on your Orbit MFD for a given Alt. You can follow the Venus approach.
The Venus approach (within 5 or 6 G):
24. Set up your Orbit MFD with Ref set to 'Venus'. Press PRJ on your Orbit MFD until this shows Frm ECL Prj SHP. Press the HUD button on your Orbit MFD. This should show your ships relative TAS velocity relative to Venus now. Make note of this since importantly this will aid in the determination of your burn for corrections.
Also on your HUD make not of the Green Circle Positive position. Since you are in rotation around the sun, there may be significant deviation of this value instantaneous velocity relative to the prograde ship's position. You may need to swivel the your view around by right mouse button hold and rotating your mouse to find the Green Circle positive and Venus respectively. If you lose, you green HUD readings as I did , you restore these simply by going to the Orbiter Menu, selecting Camera and choosing the Target tab, and then selecting 'Focus Cockpit'. Optimally for course corrections, I'd suggest your ship be at a relative velocity on the TAS reading no more then several K. Since it faster and easier to make changes. If you need to reduce your velocity. I recommend a retrograde burn to reduce your velocity so that TAS is reading within several K.
25. The art of manual correction simply put can be done in several ways. In principle the simplest with the Orbit HUD engaged is correction in vector addictions or subtractions fashion. If you need to correct relative Z positive you'd simply aim and orient your ship, with an increased Z while watching your Orbit MFD (the most efficient burn correction nears to a positive 90 ship orientation, but usually anything at above 60 degrees will proficiently build course correction. You burn thrusters while paying attention to your Ecc and PeA values which should decline. You can do this until you notice that have reached an optimum or you would only add to these values with furthered correction burns. On the relative XY plane you can change your craft's orientation so that you are approximately 90 degrees relative to your planet in the opposite direction of your craft's Green Circle Positive Velocity HUD indicator. Once within reasonable correction amount, you should ideally be within 200M km for PeA and Ecc should be a double digit integer amount or less. If you course TAS heading reads above 20 k, I recommend a retrograde burn to reduce speed reasonablly. As you develop more experience with manual course corrections, you can likely do this more efficiently without adding so much to your ship's relative velocity.
Running ahead in simulation time in increments of 1G, repeat Step 25 as necessary, reducing both PeA and Ecc...PeA should begin to approach something like 500k or reasonably to several million km, with eccentricity approaching nearer and nearer to zero...this will likely remain above 1 until your final retrograde burn for orbital capture.
Once you have established the above conditions, and your TAS is reasonably maintained, to no more then 20K, you can can prepare for the Orbital Capture.
Orbital Capture
26. Position the Ship in retrograde.
27. Once PeT is at zero. Fire thrusters, until Ecc approaches is near zero (or within by a couple digits to the right of the decimal point). If you are still off you can make corrections as shown in Step 8.
Congratulations made it to Venus!
When you run the burn its important to keep in mind that Earth is rotating around the sun at 108,000 km /h relative the Sun, even though your delta v shown in the opposite direction relative Earth's rotation and seemingly in the opposite direction when departing at ejection point, your craft is still moving in counter clockwise positive angular motion relative the sun. Basically your craft moves on an inner elliptic relative Earth's past the sun, gaining instantaneous velocity as it nears the sun and the slingshot's toward Venus on the opposite side of the elliptic (relative start). Venus instantaneous average angular velocity is approximately 20,030 km/h and while technically Venus is one of the only planet's whose orbital motion in clockwise in the Solar system relative all other planets. Technically the linear speed differential between the two planets is in the order of roughly 128,000 km/h here, or in other words, if physics of orbital motion weren't applied here to our advantage, we might have otherwise a lot of braking energy applied getting from one planet to the other!
Some fun unlimited fuel challenges are matching the orbital elliptic of Venus's by running burns on Apoapsis and Periapsis to achieve a similar orbit to Venus's. You can do this by procedure using the Orbit MFD settings mentioned above. If you wanted to do this on the quick, you can use your Lua Console to set your MJD date to near both burn points, otherwise, you'll be in for much longer real time waits even at higher given sim rate options. Function control for this is oapi.set_simmjd(MJD) where MJD is your input time format in Julian date format.
Will likely set a much higher altitude at 10M km from Earth for negative ejection burn here. This should provide more efficiency and altitude stability on the negative delta v ejection burn. As a reminder the ejection burn I believe means running a negative velocity (relative to an existing positive retrograde motion) whose orbital velocity is equal and opposite at such altitude (and then adjusting for altitude loss) and then applying delta v. This means the total ejection I believe if altitude is maintained stable at 2 x (existing TAS...burning off retrograde motion to turn to negative retrograde motion which will flip on your TAS indicator) plus your negative DV. Altitude loss will typically add some to your necessary formulation since higher instantaneous velocities are typified at lower altitudes, and thus change change the nature of your elliptic. Another possible solution that I've considered studying here in the unlimited fuel case (likely not as great a solution since you are working on more fuel burns), is creating an inner solar system elliptic, then burning at perihelion (periapsis relative the sun) so that your elliptic is less then Venus. Running the Transfer MFD and searching intercepts and running running a prograde burn at the right ejection point on the inner elliptic (relative Venus's).
Update:
Ran a successful mission with some caveats. First, I highly recommend a high altitude Earth orbit in my case 10.5M km. While in terms of periodicity of the higher oribt means more sim time waiting there are a couple of aspects that I liked for this ejection setup: less altitude loss, and less fuel spent/burn time spent in reaching negative delta v ejection. The first round elliptic appeared to be fruitless for tracking and subsequent orbits would take longer time lengths for in terms of a lengthier periodicity. Instead I modified my approach track doing the following. I burned retrograde at perihelion to run a smaller radial elliptic relative Venus's orbital elliptic. From this point, my craft's periodicity on the elliptic being different would translate into more optimal intersections relative the Venus's elliptic path...my shuttle were generally moving with differences in angular velocity because of a greater then 0 eccentricity of my Sun relative orbital track and being non matched to Venus's sun relative orbital eccentricity. This were a little bit of a go round the merri go round track. Basically to achieve this I used the the Transfer MFD at several places performing a combination of prograde and retrograde burns. The burns themselves were surprising short (a modest less then 2 k burn in most cases). The bigger burn were the perihelion retrograde burn (more likely no more then a 10 k burn on earth for ejection) to an inner elliptic path relative Venus's. While I did perform some initial manual course correction burns on the final approach (very modest relative Venus speeds a little above 2k TAS). I like this approach the best since it seemed there were greater opportunities for fuel economy use while providing many opportunities for the approach even if something went wrong. The biggest burn generally were the Earth based ejection point overall. I liked this especially so because my approach track relative Venus started at a very modest 2.2 k venus relative TAS. And the fuel spent for orbital capture on the periapsis retrograde burn ended at 7k TAS Venus relative. My overall sim time on this trip started 52192 and ended 52624 or 432 elapsed modified Julian days.
 |
| In figure: 1. Here ship's intecept shown solid gray line is matched to the dashed yellow line representing where Venus will also be on ship intercept. 2.While the actual time has elapsed for launch we are generally in line to our launch position 3. TrL represents the angle on the rotation plane for launch. |
 |
| The circled gray lines represents the the perihelion point where retrograde is performed (both in time to reach), and in terms of point of position graphically. |
 |
| Noting the Transfer MFD on the right up on the display, aiding for retrograde and prograde burns. At this point setting, our source to the glider, and using Venus as a Target. |
Step by Step:
1. Starting on the ground at Earth. Pull up your Transfer MFD (Press SEL next to MNU just below the MFD console). Set Ref to 'Sun' (once pressing the REF button a little menu appears, you can press Enter as Sun is default), Source to 'Earth' (when the menu appears for selection press your arrow keys up or down to select your given planet), and TGT to 'Venus'. Press HTO to engage the intersections search. Next Adjust your by pressing holding your DV- button until the dashed green line intersects the inner yellow ellipse representing Venus's orbit. Here you can rotate positive or negative the Ejection window by pressing the EJ- or EJ+ buttons and holding this. You will need to align the gray line with the dashed yellow line. If no intersection appear at the given launch DV you can make adjustments to your DV- or DV+ as needed while maintaining the intersection at least two points the dashed green yellow ellipse with the solid yellow line. If no ejection DV appears to suffice for intercept at this ejection position, then you will need to adjust your Ejection position pressing the EJ+ or EJ- buttons. If the the launch date is in the the first three quadrants < 270 degrees from your present position. I recommend using the Lua consolej and using oapi.set_simmjd(MJD) to change your Earth relative position so that you are slightly elapsed on the launch window. While its not 365 MJD exactly per year for Earth's orbital rotation, this provides you a rough estimator for setting MJD dates...simple add days to your existing MJD date. I do this in integer formats which works fine. Once having found a suitable intersection. I've also found setting the Ejection time slightly elapsed basically Earth's position is just slightly greater then (< 180 degrees for earth's position ) or slightly less then (> 180 degrees for Earth's position). Then adjust your DV either adding or subtracting DV as indicated above while maintaining intersection of your dashed green line with the solid yellow line (at two points). The reason for this is that actual predicted position of the planet relative time elapsed for your craft's motion seems to be more accurate doing this.
Once a suitable ejection time is found and you are at or slightly elapsed to launch time, you can now launch.
2. Go ahead and set on the alternate window your Orbit MFD set the REF to 'Earth', and set TGT to 'Venus'. Press PRJ on your Orbit MFD until this shows Frm ECL Prj SHP. Make sure your PeA (periapsis) and ApA (apoapsis) values are in km as opposed to radians, you can easily see this by the k for km designation or M for radians designations. Its easy for me to see relations of altitude in km unless you understand the relation of radians to altitude, you can change to radians or km respectively by pressing the DST button on the Orbit MFD console. Its important to note when you climb the PeA value later. So keep this in mind.
3. Press the HUD button on your Orbit MFD console. This ensures your TAS (Green Hud indicators are set for Earth relative readings).
4. Presuming you understand basic flight maneuvering. Make sure your Surface HUD is engaged. If you are on a standing launch pad, use the hover button, increasing this positive until you have flight lift. Next, once at 1k in altitude engage throttle full for speed. Disengage your Hoover speed, and lift your gear. Increase your altitude pitching the nose up generally at around 60 degrees, generally speaking anywhere between 40 and 60 degrees seems fine, the climb is slow at lower pitches. Once you climb to above 50 km you will begin to notice change in your crafts aerodynamic lift. At 75km altitude I recommend engaging your Orbit HUD using the button in the upper left of your console. At this point if handling become difficult you can stabilize your craft using the Kill Rotation button.
5. We will be achieving a high Earth orbit altitude here at 10M km, so the climb will take some time here. I recommend that you craft is stably maintained oriented such that your craft is climbing away from Earth, you can note this by your Orbit MFD s PeA value as this inclines further and further until showing 10 M km, you will likely need to disengage your engines, but first you will want to make note of your crafts speed. You will need to be flying at around 4k on your TAS for stable orbit, mostly you want to make sure your craft is moving in positive motion reasonably at least within 2 or 3 k TAS prior to reaching PeA. You can fast forward your simulator using the Speed simulator functions, I recommend stepping this up no more then a 1000 times, generally though here I don't recommend this initially using this above 100 times especially on the first PeA ascent.
6. Press the Prograde button (upper right of your ship's console). This should be lit engaged.
7. Make note of your ApA and PeA values.
8. Once ApA and ApT have elapsed to zero. You will need to fire your engine thrusters until Ecc is nearly close to zero (don't worry if its slightly off). If you need to increase your ship's overall altitude you can fire in Prograde position your thrusters once your ship is positioned to ApA and PeA separately. You will want to make note of the Ecc value on your Orbit MFD when running a burn. If you want to decrease altitude you do the same as except making sure that your ship is in Retrograde position (pressing the Retrograde button and making sure this is lit).
Now's a good time to do a quick save, so that you can always restart your scenario if you like.
Let's align the ship to Venus's orbital plane.
9. Press SEL (just below the MFD console) on your existing Orbit MFD.
10. Select the Align Planes MFD.
11. Once your ship on the rotation plane is at or near AN your ship will need will need to be in the Orbit-Normal (-) position, while being in the opposite position (Orbit-Normal (+)) when on or near the DN position . You can speed your simulator up by 10 or 100 times you can see what position is moving towards here. Once determining the position that you are headed towards. Set your ship into the given Orbit normal position as necessary well in advance.
12. Follow the instructions on the Align Planes MFD when it says "Kill Thrust" make sure to kill your thrust. Your Rinc value should decline as you burn, and this should close to zero (don't worry if its not exactly zero).
13. Press SEL just below your Align Planes MFD, and select the Orbit MFD again. By default this should have your Earth orbit settings.
14. This point on your Transfer MFD, I will assume your DTe has elapsed. Earth's position Shown solid green should appear at or near the dashed green window ejection. Procedurally you can use the Lua Console for time acceleration...keep in mind 100k time translates into approximately 1 day of time...
15. Position your ship in Retrograde. Initially when you fire I recommend your celestial bodies view is engaged. Visually I make note of this since HUD oribtal readouts will change as you burn on ejection. Generally I work to fire the ship maintaining orientation at the constellation group that I originally fired in orientation pointing towards.
16. Make note of TrL values on your Transfer MFD. This will be the point at which you fire engines to engage ejection. On your close approach to the TrL value, you will want to make note of your TAS value (this is your Earth orbit relative speed). You will need to add this value to the negative DV shown on your transfer MFD. Your actual TrL position is given on your Orbit MFD. Once your TrL elapses fire engines.
17. Hit the Kill rotation button on your ship, and maintain orientation on the constellation group that you are at. It doesn't need to be perfect, but you can hit as necessary the Kill Rotation button to maintain your crafts altitude. There are two parts to the ejection: zeroing out your velocity, and increase your ship's velocity that you computed in step 16 (this is negative orbital plus delta v ejection). I've added a slight amount of orbital velocity for slight loses in altitude (although I didn't formal compute the precise negative orbital value needed here)...my addition were in the range of 20 on TAS. My altitude restabilized at around 9.6M km, so don't worry if you have lost some altitude.
18. Once reaching the desired ejection velocity. Kill thrust. We'll set up your Orbit MFD for a new reference.
19. Change REF to 'Sun', change TGT to 'Venus'. Here you will note at this point the relation of your Orbit MFD of your ship's trajectory being roughly similar to the projected orbital trajectory shown in your Transfer MFD. Don't worry if the shape is rough here, it will change and stabilize over time as you move upon distance gained moving away from Earth. At 250 M km out (from Earth), this should begin to assume generally the shape and form shown in your Transfer MFD, but no worries even if you are off, other things can be done.
20. Since there is a lot of simulation time involved in this. I personally like to run simulation ahead in steps of 25, 50, 100 days to see how close projections are availed here. At some point if it appears the position of the planet for whatever reasons is unlikely to be at the the projected position (or remotely near it). I've set up a new approach procedure. If it appears that your trajectory is way off on the intercept to Venus's position move to the alternate approach track shown below.
The alternate procedure
You can use the Lua console to move forwards or backwards in time as indicated using the oapi function mentioned above. Move to within approximately no more then several hundred k seconds, and then you can manually adjust on the decimal MJD with function to reduce time to near or less then 100k from relative to PeT. Within 100k I run sim time using the menu speed controls.
21. Do a retrograde burn PeT, PeA shown on your Orbit MFD. The burn need not occur to the extent of modifying your trajectory to zero Ecc, but fitting this trajectory to fit on or inside Venus's orbital path.
22. Reconfigure your Transfer MFD Source, by Pressing SRC then typing 'GL-01' if you using the glider or your craft's code handle and pressing enter.
23. You will use the same procedure as in Step 1 above except you will need a positive delta v burn. If you don't see good alignments here. I recommend cycling time forward say by increments of 25 days and rechecking as actual planet to ship positions will provide new transfer possibilities. At some point you will find a good transfer opportunity.
Once you are within 5 or 6 G distances on your Orbit MFD for a given Alt. You can follow the Venus approach.
The Venus approach (within 5 or 6 G):
24. Set up your Orbit MFD with Ref set to 'Venus'. Press PRJ on your Orbit MFD until this shows Frm ECL Prj SHP. Press the HUD button on your Orbit MFD. This should show your ships relative TAS velocity relative to Venus now. Make note of this since importantly this will aid in the determination of your burn for corrections.
Also on your HUD make not of the Green Circle Positive position. Since you are in rotation around the sun, there may be significant deviation of this value instantaneous velocity relative to the prograde ship's position. You may need to swivel the your view around by right mouse button hold and rotating your mouse to find the Green Circle positive and Venus respectively. If you lose, you green HUD readings as I did , you restore these simply by going to the Orbiter Menu, selecting Camera and choosing the Target tab, and then selecting 'Focus Cockpit'. Optimally for course corrections, I'd suggest your ship be at a relative velocity on the TAS reading no more then several K. Since it faster and easier to make changes. If you need to reduce your velocity. I recommend a retrograde burn to reduce your velocity so that TAS is reading within several K.
25. The art of manual correction simply put can be done in several ways. In principle the simplest with the Orbit HUD engaged is correction in vector addictions or subtractions fashion. If you need to correct relative Z positive you'd simply aim and orient your ship, with an increased Z while watching your Orbit MFD (the most efficient burn correction nears to a positive 90 ship orientation, but usually anything at above 60 degrees will proficiently build course correction. You burn thrusters while paying attention to your Ecc and PeA values which should decline. You can do this until you notice that have reached an optimum or you would only add to these values with furthered correction burns. On the relative XY plane you can change your craft's orientation so that you are approximately 90 degrees relative to your planet in the opposite direction of your craft's Green Circle Positive Velocity HUD indicator. Once within reasonable correction amount, you should ideally be within 200M km for PeA and Ecc should be a double digit integer amount or less. If you course TAS heading reads above 20 k, I recommend a retrograde burn to reduce speed reasonablly. As you develop more experience with manual course corrections, you can likely do this more efficiently without adding so much to your ship's relative velocity.
Running ahead in simulation time in increments of 1G, repeat Step 25 as necessary, reducing both PeA and Ecc...PeA should begin to approach something like 500k or reasonably to several million km, with eccentricity approaching nearer and nearer to zero...this will likely remain above 1 until your final retrograde burn for orbital capture.
Once you have established the above conditions, and your TAS is reasonably maintained, to no more then 20K, you can can prepare for the Orbital Capture.
Orbital Capture
26. Position the Ship in retrograde.
27. Once PeT is at zero. Fire thrusters, until Ecc approaches is near zero (or within by a couple digits to the right of the decimal point). If you are still off you can make corrections as shown in Step 8.
Congratulations made it to Venus!
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