Go Back   Orbiter-Forum > Orbiter Space Flight Simulator > Tutorials & Challenges
Register Blogs Orbinauts List Social Groups FAQ Projects Mark Forums Read

Tutorials & Challenges Feel free to publish your tutorials, challenges, & flight scenarios in this forum.

Thread Tools
Old 11-30-2008, 02:52 PM   #1
Smile Challenge: Land the Lunar Module on any Galilean moon (AMSO)

I saw a thread on the old m6 forum where someone crashed an AMSO Command Module into Jupiter's atmosphere. I've been trying to do something cooler. Using Apollo 17, I followed the Galileo probe's VEEGA trajectory in 1989 to get to Jupiter, and was able to aerobrake into a high elliptical orbit. This is an ongoing attempt to try to land on Ganymede and return to Earth. However, I realized it would take a lot of complex flybys to match orbits with Ganymede, so I'm posting these scenarios in case anyone wants to try a landing on one of the Galilean moons (and optional return to Earth if possible, using flybys to boost your ApA so the final escape burn won't cost too much Dv, then flybys of the inner planets to slow you down).

The challenge is to land on any Galilean moon. Addons required: AMSO.

Here are 3 scenarios. You can start from any one you want, or plan the mission from scratch if you like using any launch date and slingshots you want:

1. Launch:
This scenario starts 70 seconds before launch. Press J at scenario start to retract launch tower arms. Press K at sim time 60 seconds to launch. The TVI burn will take all the rest of the 3rd stage's fuel, leaving only 15-20 m/s left to burn. Also, since TransX doesn't compensate for the Moon's gravity at all, I had to use about 15% of the SM's fuel for course corrections just on the way to Venus.

In order for the AMSO launch autopilot to not go crazy (starts turning back and forth) after 1st stage sep, I had to remove these lines from the scenario file:
MJDLOI 41661.824560
MJDLDG 41662.829838
MJDSPL 41670.809016
I don't know why that worked, but it did.

When doing the 2 Earth flybys, you can compensate for the Moon's gravity by doing the flyby once, ignoring the Moon, and see how it affects your flyby path, then restart from before you enter Earth's SOI and course correct to put your flyby path on the opposite side of the end of the yellow dotted line (press VW in the slingshot stage to get this view) so the Moon pulls you into the correct flyby path. You can also use translation RCS after just entering Earth's SOI to manually fix the path before the flyby if it's not too far off (since manoeuvre mode doesn't work the same way in a slingshot stage apparently). Another way to compensate is to do MCCs only at ETAs that are a multiple of the Moon's orbital period (Enc MJD - (27.321662 * n) days)

The 2nd Earth flyby will probably take you just above the atmosphere, careful you don't burn up.

2. Cruise to Jupiter:
This scenario starts well after the VEEGA flybys and is about 750 days out from Jupiter. If you make no course corrections, you will crash into Jupiter.

3. In orbit around Jupiter:
This scenario is just after aerobraking into Jupiter orbit. The orbit is a bit off-plane with the moons though. I had a PeA of 610km, and ended up in an elliptical orbit with a post-aerobrake ApA of ~0.06AU which got perturbed by the moons down to 0.031AU. When going through the atmosphere, I turned on the retrograde autopilot in an attempt to shield the LM (which would probably not work in real life). After exiting the atmosphere, the SM had 66.7% fuel remaining in the SM.

Last edited by 2552; 12-16-2008 at 12:05 PM.
2552 is offline   Reply With Quote
Old 12-27-2008, 09:05 AM   #2

Interesting. If I use the 2018 TransX VEEGA plan from Piper's
Io Orbiter addon
, the TVI burn can be completed by the SIVB 3rd stage with ~25m/s dV to spare, for a savings of ~43m/s over my 1989 plan.

Here's a launch scenario that uses Piper's 2018 Io Orbiter TransX plan.
2552 is offline   Reply With Quote

  Orbiter-Forum > Orbiter Space Flight Simulator > Tutorials & Challenges

amso, jupiter

Thread Tools

Posting Rules
BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
Forum Jump

All times are GMT. The time now is 01:30 AM.

Quick Links Need Help?

About Us | Rules & Guidelines | TOS Policy | Privacy Policy

Orbiter-Forum is hosted at Orbithangar.com
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Copyright 2007 - 2017, Orbiter-Forum.com. All rights reserved.