Question Post your built-in challenge scores

[flytandem]

another run at challenge 3 with 2429.12 Kg used.
grabbed a printscreen when the completion dialogue box came up (attached)

 

[dgatsoulis]

another run at challenge 3 with 2429.12 Kg used.
grabbed a printscreen when the completion dialogue box came up (attached)

Very nice!:thumbup:
I'll have to find a more elegant way to align my planes, than just swinging by the moon twice. Oh well, back to work.

-------------------EDIT------------------
Back from another great Orbiter session. Challenge 3 completed with 2399.10 Kg.

The attached playback shows 2405.25


CLARIFICATION: This flight was made with the "Gravity-gradient torgue" and "Non spherical gravity sources" checked, in the Orbiter launchpad.

 

[flytandem]

2399! wow. Better than my best shot at it might ever be. I saw in the playback you had a very high Ap after the orbit insertion at the moon. I had tried that but found the resulting position of the craft wandered unpredictably and took more fuel to keep on track than the savings. But you managed to do it. Great.
My 2429 had the first Ap about 6 moon diameters and had some savings for the plane change and the rendezvous happened fairly quickly, but you definitely had better savings from that higher Ap.

 

[dgatsoulis]

Thanks flytandem. Actually, i just finished another session with 2378,54 kg. Unforunately, i didn't record that one. I'll give it another try tomorrow. There still is some room for improvement. I think it can be done with about 15-20 Kg less.

I had tried that but found the resulting position of the craft wandered unpredictably and took more fuel to keep on track than the savings.

The Map program of IMFD is very helpful for keeping track of your trajectory, where other MFDs fail.
On the playback, i have it already set for the target, and it guided me all the way. Of course for finding the initial window, i used TransX. I made the TLI on the second node, when the moon "is to the left" on TransX, because it's closer to the Earth by 40M, so it takes a little bit less dV to reach it.

 

[flytandem]

I also chose the transfer to the "left" on TransX, meaning waiting a few days before going. I set up the arrival Pe to be exactly at the node with the orbit of the wheel and this made the high Ap of the first orbit to also be at the node. Then a mix of both plane change and retrograde at the Ap had it return in plane with the wheel to a second retro burn at Pe to reduce the Ap to be a bit above the wheel so one orbit later it met the wheel. Doing the high Ap plane change and mixing both plane and retro into one burn also minimized the fuel needed.

edit: going back and re-flying from lunar orbit insert I used IMFD to assist in setting up a higher Ap. It helped reduce the plane change by 20 KG making it 2409. Not sure if another 10Kg is possible with this method. It would mean making an even higher Ap.

 

[dgatsoulis]

Another go at challenge 3.
I tried to go for the lowest Perilune i could (~40Km), that would get me the lowest Rinc to the Lunar wheel possible (~25 degrees).

Then, at Perilune, i burned retrograde to be captured by the Moon's gravity, trying to get my Apolune as high as possible. (APA ~56.97) The eccentricity of that orbit was 0.954!

This allowed me to make the plane change with minimum fuel usage.
The result: 2353,56 Kg of fuel used.

I think that this is really close to what can be done in this challenge.

Playback is attached. (Shows 2362.94)

CLARIFICATION: This flight was made with the "Gravity-gradient torgue" and "Non spherical gravity sources" checked, in the Orbiter launchpad.

 

[jthill]

Challenge 1...

Okay, there's definitely more to get out of this plan but it'll take a better pilot than me. Challenge 1, 5454.69. I want an autopilot to help out with the gimballing for L/D, the workload trying to keep 3.5-4deg AoA when possible while aligning (and not missing MECO) gets intense, though this one stabilized early.

No transx, just surface/align for ascent, orbit/sync for MECO and overtake at tg apoapsis. Final alignment while phasing, one orbit before rendezvous.

Here's the playback.

 

[jthill]

Little milestone: <5400 on challenge 1.

Using my meager portion of His Noodly Appendage, I realized that yanking the nose skyward during climbout, even though it kept DNP low, it also broke laminar flow over the wings, so I smoothed that out quite a bit. Using the Flight Data Monitor, I learned the DG can generally handle up to about 4.5 degrees AoA, so I targeted lower DNP and correspondingly higher AoA for a lot of the ascent (though still well below separation for safety). And I also realized that L/D ratio really doesn't mean much when DNP is near zero, so when approaching MECO I dropped AoA to near zero.

Net result: dock at 5395.55 total fuel used.

Playback attached, I don't know why the one I added to the earlier post vanished, I didn't do that. I think it might be that it wasn't strictly an "attachment"... whatever.

I see the DG doesn't record trim and gimballing, it'll make the AoA in the recording hard to understand if you're not used to using them.

 

[blixel]

I've been practicing rendezvousing and docking with the ISS using the Quickstart scenario. I overlooked the Challenges folder; I'll have to start using the Challenges from now on so the system will report my stats for me. For now though, here is my most recent effort.

Delta-glider propellant starting:
MAIN = 12,836
RCS = 600

Friday, May 20, 2011
Quickstart scenario to ISS.
Propellant stats after dock
MAIN = 7,230
RCS = 574

12,836 - 7,230 = 5,606
600 - 574 = 26
5,606 + 26 = 5,632 total used​

Note: I have Radiation pressure on, and Nonspherical gravity sources and Gravity-gradient torque off. I know from experience that I use more RCS with Gravity-gradient torque turned on, and I have not yet successfully docked with Nonspherical gravity sources turned on.

I've made many trips to the moon, but I only started learning how to rendezvous with the ISS more recently. I feel like I only started to fully understand all the steps within the last half-dozen or so attempts. It is now very clear to me.