OFMM Mission Discussions

[garyw]

How is discussing a mission (even though it's the specific details) off-topic? Besides, I'm done talking about that mission.

Because this thread was never planned to be about the fine grain details of a specific mission that hasn't been assigned yet.

It doesn't seem like the plan isn't going to change a whole lot, anyway.

Quite possibly but by going into fine details of one mission you may well be putting others off discussing the overall plan which is where I wanted this thread to go.

There was no "collision of conversations" going on.

I hope that a flamewar doesn't start here.

It won't. I'll stop any flames. The important thing here is to have fun with OFMM.

My original plan was to start out with big picture threads (roll call, mission discussion, back room work, etc) and then go down into the fine grain details with specific back room threads for missions. The idea here would have been that there would have been a mission thread and a mission back room thread where everyone could have given input in case of an issue - a bit like mission control talking though a problem.

However, I can see now that it won't work so I'm going to transition OFMM to the model that OFSS has used.

 

[Pipcard]

Then I am truly sorry. Is there anyone who still wants to discuss the overall plan (even though there's an assignment thread now)?

 

[garyw]

I'm changed this to the Mission discussions thread, makes more sense to keep the discussion over missiond details in here since this is what the thread has been used for.

 

[astrosammy]

How many launch windows to Mars are we going to use?

If we use one launch window for OFMM-7 and 8, the second for 14 and 15,
the third for 16, 17 and 20 and the fourth for 23 and the following missions,
we would need around ten years of simulation time.

It would also be great to know the first window we'll use.For example, the first one in the 2020s would be in summer 2020.

 

[Arrowstar]

I suspect that's something the 'back room' folks will be working on.

 

[garyw]

I suspect that's something the 'back room' folks will be working on.

Yes it is. I'll create that thread later this week once I've had a chance to work out the sort of dates I plan on using. It's then up to the back room guys to tell me how wrong I am and how we will really do it. :lol::thumbup:

 

[Arrowstar]

I'm finishing finals on Wednesday evening, so if you really want me to do well, you'll hold off on posting that thread until then! :lol:

 

[garyw]

I'm finishing finals on Wednesday evening, so if you really want me to do well, you'll hold off on posting that thread until then! :lol:

We can't have our chief trajectory officer distracted so no back room threads until Thursday and good luck with your finals.

 

[Arrowstar]

We can't have our chief trajectory officer distracted so no back room threads until Thursday and good luck with your finals.

Finals are over, let the distractions begin.

 

[MaverickSawyer]

Agreed. :hitit:

 

[Cras]

How realistic are we going to be treating the vehicles here?

I would suggest that we requires certain segments in each mission that pertain to the activation of the actual manned vehicles.

Such as, while they may be fun to fly in Orbiter, no manned XR-2 or XR-5 should fly to the moon on a direct ascent trajectory.

I see a LEO insertion beneficial as it allows for checkout of the vehicles systems and condition after launch, and provides an abort option should the vehicle have become disabled during the launch somehow. LEO is a far better place to learn the ship cannot handle the cislunar cruise than already on the way at 35k feet per second.

Now I understand that the odds of something going bad is in orbiter is nothing like it is in real world situations, and there is always that ability to revert to a quicksave, or just start over. Starting over I think should not be a permissible option, and a quicksave should only be used should the commander suffer an Orbiter ctd.

So should something bad happen in launch, however it is decided we get these things into space, an LEO segment in the mission provides great flexibility on how to salvage things.

Just some food for thought.

 

[garyw]

This has all been discussed and agreed earlier in this thread. I see no reason to start changing things now. You all hand your chance to change the mission plan and people were more concerned with patches.

The whole quicksave thing was mentioned here. there is no way to check to see if they have been used or not.

So, either the missions stay as they are or I shut down my involvement with OFMM.

 

[Pipcard]

people were more concerned with patches.

Sorry.

 

[Pipcard]

We aren't. The James Cook was requested by the people participating so that's what is now going to be used.

Can we make a last minute change so that we use the Deepstar (it also has a rotating artificial gravity part)? Mission 1 hasn't even started.

But the Cook is fine too.

 

[garyw]

Can we make a last minute change so that we use the Deepstar (it also has a rotating artificial gravity part)? Mission 1 hasn't even started.

But the Cook is fine too.

It was you who demanded that the james cook be used!!!! and so what about the rotating gravity wheel part? You even said that you didn't want to have any sort of mission failures so I'm confused as to why you insist on a gravity wheel?

And Mission OFMM-P1 was going to be posted on Tuesday but I'm confused as to where we are as it's all changing even though you said that the mission plan was fine.

 

[Pipcard]

It was you who demanded that the james cook be used!!!! and so what about the rotating gravity wheel part? You even said that you didn't want to have any sort of mission failures so I'm confused as to why you insist on a gravity wheel?

And Mission OFMM-P1 was going to be posted on Tuesday but I'm confused as to where we are as it's all changing even though you said that the mission plan was fine.

I know I already asked for the Cook, sorry.

A crew that has spent over a year in space will undergo a lot of stress with landing on Earth. Better to send up an XR-2, dock and then take the crew off and land with a CDR/PLT who are trained for that and haven't spent the best part of 2 years in less than 1G.

Didnt think about that...since there will be no gravity wheel, like the Arrow.

And that's the why for the gravity wheel.

Just forget it, we'll stick with the decision. Why do I sometimes feel like I'm being a bad contributor to this project?

 

[garyw]

And that's the why for the gravity wheel.

So you want to keep a ship with a gravity wheel but you want deepstar now and you want to scrap OFMM-29 because of the gravity wheel?

Ok, I'll move these posts to the mission discussions thread and see what others have to say. It seems that there needs to be some more mission planning before I release the first scenario.

---------- Post added at 23:34 ---------- Previous post was at 23:32 ----------

Why do I sometimes feel like I'm being a bad contributor to this project?

Maybe because you keep changing your mind just when things seem to be nailed down?

 

[Pipcard]

So you want to keep a ship with a gravity wheel but you want deepstar now and you want to scrap OFMM-29 because of the gravity wheel?

I don't want to change anything now, because I now realize that I don't want even more debate over the missions (another kind of "development hell").

I said "Just forget it, we'll stick with the decision."

 

[MaverickSawyer]

Hey, guys, just pick a ship and stick with the damn thing.
BTW, I am ready to fly the OFMM-P1 mission at any time.

 

[dgatsoulis]

There have been some concerns, in the trajectory office backroom. about the power that the Mars ship can yield. For reasons explained here, we have already seen that the total weight of the supplies that can be delivered to the James Cook cannot be more than 467 tons. If that was all fuel and the ship had nothing else onboard, it would give a dv of 127 km/s, which is a slight overkill.

But if we assume a 70 - 30 ratio (70% for air, food, water and equipment - 30% fuel) for the weight of the cargo, we get 140.1 tons of cargo that consists of fuel. Calculate in a factor of 0.85 for the weight of the containers and the fuel becomes 119.08 tons. So out of the 467 tons, 347,92 need to be added to the emptymass and 119.08 are the fuelmass. Let's add the weight of the two XR2s that will be docked and then make the calculation for the dv:

dv = ln((EmptyMass+FuelMass)/Emptymass)*exhaustV
EmptyMass=350000+347920+(2*16080)= 730080kg (the weight of the Cook + supplies for the trip + the weight of 2 empty XR2s).
FuelMass = 119080
ExhaustV=150000
This gives us a dv of 22664,026 m/s available at the TMI burn. (22,664 km/s)

We also need to keep in mind that at least 26 tons of fuel will be transfered to the XR2s when we arrive at Mars, lowering the available dv even more.