flytandem
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The parking orbit thread had me thinking about possible update(s) to TransX. (just thinking out loud here) Definitely warrants discussion.
Currently when you have an eject planned (stage 2) and have made it to a parking orbit (stage 1), there is no direction target available for aiming the ship. For short burns around slow moving places like the moon and 800 m/s eject to Earth it's not a disadvantage to just aim prograde with the autopilot and burn when and how much it says to burn. But for long burns of say 5000 or more m/s at places that are moving fast, like the Earth, it's not as accurate as my preference which is creating a target by means of setting up a maneuver that borrows the required deltaV and then swinging it to graphically overlay the plan by date adjustment.
What If???
... a target is available for a planned eject that uses the same calculations as done for the maneuver function. Except that the date value it has in the plan is not what is actually going to be used. (see next paragraph)
The date issue is also something to think about. Usually you get into your parking orbit either 1 or many orbits ahead of the planned eject date. You warp ahead to the last orbit. You can choose an orbit that is closest to the planned eject date but your actual eject time doesn't match exactly the planned eject date. Your arrival at the Pe of the plan for the eject burn could be off by as much as 45 minutes either early or late. Being off in date is like being off in amount or direction of burn, it causes an error in the plan. This date problem is another reason I often set up a maneuver... the maneuver will be able to have exactly the correct date and thus be more accurate for the eject burn.
What If??
... there is a way to make the date of the plan to become the value of the next Pe. The idea is a click or two in Stage 2 (maybe under date adjust, after the adjust amounts like Hyper and Reset, there could be a "Next Pe" after "Reset" and before "Coarse" which is available in the list of adjust amount, and works by means of clicking either ++ or --, and works only when you are established in the parking orbit. Choose "Next Pe" then when you click either the ++ or -- TransX looks at the time to next Pe (it's already being shown in seconds in Stage 1), divides by seconds in a day to get the units in days, takes the current actual date, adds it to the time to Pe and then places this as the Date value of the plan. One then goes to the other variables in the plan and tweaks slightly the prograde, outward and plane change to get the plan to again be close to the target planet or moon. After that, one might need to tweak the relative inclination a tiny bit by means of a plane change or slight change in eject orientation. The idea is that it saves setting up a maneuver. And for that matter we are talking about relatively small changes in most cases so one could skip this date change if they were not trying to be precise in their eject. But for those wanting the precision currently only available by means of a maneuver, it could be an advantage.
One disadvantage I can think of with this method is that, when using a maneuver for the eject, I am able to mix both a tiny bit of outward or plane change into the prograde burn. This is more efficient than separating (doing a tiny plane change to get back to zero rel inc with the plan) after the date update has been made.
??
Currently when you have an eject planned (stage 2) and have made it to a parking orbit (stage 1), there is no direction target available for aiming the ship. For short burns around slow moving places like the moon and 800 m/s eject to Earth it's not a disadvantage to just aim prograde with the autopilot and burn when and how much it says to burn. But for long burns of say 5000 or more m/s at places that are moving fast, like the Earth, it's not as accurate as my preference which is creating a target by means of setting up a maneuver that borrows the required deltaV and then swinging it to graphically overlay the plan by date adjustment.
What If???
... a target is available for a planned eject that uses the same calculations as done for the maneuver function. Except that the date value it has in the plan is not what is actually going to be used. (see next paragraph)
The date issue is also something to think about. Usually you get into your parking orbit either 1 or many orbits ahead of the planned eject date. You warp ahead to the last orbit. You can choose an orbit that is closest to the planned eject date but your actual eject time doesn't match exactly the planned eject date. Your arrival at the Pe of the plan for the eject burn could be off by as much as 45 minutes either early or late. Being off in date is like being off in amount or direction of burn, it causes an error in the plan. This date problem is another reason I often set up a maneuver... the maneuver will be able to have exactly the correct date and thus be more accurate for the eject burn.
What If??
... there is a way to make the date of the plan to become the value of the next Pe. The idea is a click or two in Stage 2 (maybe under date adjust, after the adjust amounts like Hyper and Reset, there could be a "Next Pe" after "Reset" and before "Coarse" which is available in the list of adjust amount, and works by means of clicking either ++ or --, and works only when you are established in the parking orbit. Choose "Next Pe" then when you click either the ++ or -- TransX looks at the time to next Pe (it's already being shown in seconds in Stage 1), divides by seconds in a day to get the units in days, takes the current actual date, adds it to the time to Pe and then places this as the Date value of the plan. One then goes to the other variables in the plan and tweaks slightly the prograde, outward and plane change to get the plan to again be close to the target planet or moon. After that, one might need to tweak the relative inclination a tiny bit by means of a plane change or slight change in eject orientation. The idea is that it saves setting up a maneuver. And for that matter we are talking about relatively small changes in most cases so one could skip this date change if they were not trying to be precise in their eject. But for those wanting the precision currently only available by means of a maneuver, it could be an advantage.
One disadvantage I can think of with this method is that, when using a maneuver for the eject, I am able to mix both a tiny bit of outward or plane change into the prograde burn. This is more efficient than separating (doing a tiny plane change to get back to zero rel inc with the plan) after the date update has been made.
??
