Problem Lunar Transfer MFD with AMSO

[Pound4]

I have a small problem using Lunar Transfer MFD with AMSO. I've attempted to recreate the Apollo 11 mission using it, and everything goes well up until TEI. My problem is I don't have enough fuel for the burn. I usually end up with only about 15% fuel remaining in the CSM at the time of the burn, and it's not enough. Is there a way to use this MFD so that it doesn't use as much fuel so I have enough for the TEI burn?

 

[Shadow Addict]

You shouldn't have used that much fuel on MCCs and LOI alone. Did you use the S-IVb for the TLI or the CSM?

 

[the.punk]

I think 15% is way too low. I tried it and I had about 50% fuel left for the TEI burn. You must calculate your TLI good and don't eat up too must for MCCs as said above.

 

[jalexb88]

If you follow the historical trajectory by inputing the right information in LTMFD such as PeT (time of arrival at the moon) and PeA (altitude of closest approach) and TOA (time of alignment with the landing site). you should be left with plenty of fuel for TEI. Last time I tried I had around 40% fuel for TEI. You just have to input the right info. Heres a website with information on how to fly apollo "by the numbers". Using that along with LTMFD makes it very precise. I landed Apollo 8 in the pacific about 45 seconds later the the real mission. Remember if you want to have enough fuel, you have to fly the mission exactly as described in the real timeline.

http://history.nasa.gov/SP-4029/Apollo_00g_Table_of_Contents.htm

 

[Shadow Addict]

The only way I can imagine burning that much fuel before TEI is if he used the CSM for TLI, unless the MCCs were VERY wasteful.

EDIT: Nevermind, I'm doubting that the CSM has enough fuel for TLI and LOI, so I suppose it was just wasteful MCCs.

 

[jalexb88]

LOL through experience, I can confirm that the CSM has not enough fuel for TLI alone.

 

[Pound4]

Yeah, it probably would have been a smart idea to input the right data before the TLI burn, letting the S1VB put me on the right course rather than eating up the CSM fuel on the way to the moon to do that.

Without inputting data before TLI and just doing TLI with what's already set, I ended up doing one MCC that used about 5% of my fuel in the CSM, the LOI burn was about 345 seconds, which I'm sure is way too long, and then the base-alignment burn used about 15% of my fuel.

 

[jalexb88]

One of the cool things about LTMFD is that you can set a TOA (time of alignment) during TLI and MCCs, so you just input the time of the actual landing and everything is taken care of. No need for a base alignment burn after LOI.

 

[Shadow Addict]

Base alignment shouldn't be done in lunar orbit. It should be done during translunar coast or during TLI to save fuel.

 

[Pound4]

Thanks everyone for your help! I just did the full Apollo 11 mission for the first time. This time, I had about 35% fuel for the TEI burn, which was just enough, and I managed to land in the Pacific not too far from the actual splashdown site, and I was only a minute and thirty-nine seconds off from the actual time of splashdown.

 

[Kosmonaut]

I have a small problem using Lunar Transfer MFD with AMSO. I've attempted to recreate the Apollo 11 mission using it, and everything goes well up until TEI. My problem is I don't have enough fuel for the burn. I usually end up with only about 15% fuel remaining in the CSM at the time of the burn, and it's not enough. Is there a way to use this MFD so that it doesn't use as much fuel so I have enough for the TEI burn?

What's TEI?

 

[Star Voyager]

Trans-Earth Injection (meaning going from Moon to Earth in this case).