Bug TransX (latest)/ Delta Glider IV: Mars Bug

[joey1405]

I took the Mars mission that came with the Delta Glider IV. I took the autopilot into a regular orbit. I was aiming for Phobos, so the azimuth was at 63 degrees. I used the latest version of TransX, not the stock. When I started my burn towards Phobos, everything was going as planned. I got the burn done perfectly and it was aligned as well. I fast forwarded in x10, until the alarm went off. I had lost my radiator. I figured I could survive without it, but things just went downhill from here. The altitude was too low, and I couldn't fix it in time. It caused me to burn up... I did all the check lists and the issue was not the ship itself. Is there a way to fix the altitude that the auto pilot goes to or is there a way to fix TransX to do it.

 

[RisingFury]

Did you use the Maneuver mode to eject? Did you point your nose into the blue cross and burnt?

 

[agentgonzo]

I don't quite understand what you are saying.
When you say the altitude was too low, the altitude over which body? Phobos or Mars? When you say you burn up, does that mean that you reenter the atmosphere and burn up in that? Phobos has no atmosphere. Did you perform any mid-course corrections? If not, then it's quite probable that you missed the target altitude as TransX isn't perfectly accurate and needs MCCs. Are you sure you set up TransX correctly, performed the burn at the right time for the right amount and in the right direction? How was the altitude wrong. Did you launch from the planet at the correct time? Were you in the correct target plane? If you were doing it from the launch mode (rather than the more accurate manoeuvre mode) did you set the correct ejection altitude?

 

[joey1405]

I don't quite understand what you are saying.
When you say the altitude was too low, the altitude over which body? Phobos or Mars? When you say you burn up, does that mean that you reenter the atmosphere and burn up in that? Phobos has no atmosphere. Did you perform any mid-course corrections? If not, then it's quite probable that you missed the target altitude as TransX isn't perfectly accurate and needs MCCs. Are you sure you set up TransX correctly, performed the burn at the right time for the right amount and in the right direction? How was the altitude wrong. Did you launch from the planet at the correct time? Were you in the correct target plane? If you were doing it from the launch mode (rather than the more accurate manoeuvre mode) did you set the correct ejection altitude?

First, I did use manuvere mode.

It was over Mars. I burnt up because when I did the ejection burn, it lowered my altitude to the point of sub-reentry. I never escaped the orbit of Mars, and my debris went straight to the surface. the periapsis was too far into the atmosphere so the ship burnt up too quickly for me to do anything about it. I didn't know how far in the atmosphere it would go, but now I know it was too far. Everything was accurate. The deltav was off by about 0.005 and thats.

I've never used launch mode, because I'm new to this version of TransX. How does it work/is there any tutorials?

 

[agentgonzo]

It was over Mars. I burnt up because when I did the ejection burn, it lowered my altitude to the point of sub-reentry.

Ejection burns should always be prograde (or very nearly prograde). If it's lowered your periapsis, then you have either set up the plan wrongly, or you are burning at the wrong time or in the wrong direction.

Flytandem has some good tutorials. There's even one on a transfer to Phobos that will probably help you.

 

[jinglesassy]

yeah and the auto pilot in the dgiv is for earth not for mars so it may be diffrent

 

[Quick_Nick]

There are three directions when setting up a burn in TransX: Prograde, Outward, and Plane Change. You shouldn't need to mess with either of the last two. Only change Prograde and be sure to increase it, don't go negative. Assuming you only have prograde, just run the prograde autopilot. Unless you were too low all along, burning prograde will never cause you to reenter.

 

[2552]

yeah and the auto pilot in the dgiv is for earth not for mars so it may be diffrent

The DGIV has autopilots for Earth, the Moon and Mars. P103 and P104 are for Earth, P105 is for the Moon, and P106 is for Mars.

 

[joey1405]

Ejection burns should always be prograde (or very nearly prograde). If it's lowered your periapsis, then you have either set up the plan wrongly, or you are burning at the wrong time or in the wrong direction.

Flytandem has some good tutorials. There's even one on a transfer to Phobos that will probably help you.

I did use those tutorials, I aligned it inside of the dartboard shape view and burned like it told me to. I'm starting to guess that it was the wrong time to do that because it was slightly retro and thats what caused it.

 

[ijuin]

Be aware that whenever you set up a maneuver, you are also specifying what time the maneuver is to take place. In the bullseye-and-crosshairs display of transX, there should be a countdown timer showing how many seconds until the burn is scheduled. You do not want to burn until the time left until the scheduled moment is less than the expected length of your burn.

 

[joey1405]

Be aware that whenever you set up a maneuver, you are also specifying what time the maneuver is to take place. In the bullseye-and-crosshairs display of transX, there should be a countdown timer showing how many seconds until the burn is scheduled. You do not want to burn until the time left until the scheduled moment is less than the expected length of your burn.

I burned when the TransX time till burn reading reached 0...