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[Akura]

I remember in a slightly older version, the Mk1-Mk2 adapter would overheat faster than the rest of the craft. Kinda annoying when, after a several-hours-long trip, the command pod would suddenly find itself relieved of the weight of everything else(including ALL the parachutes ) because the one piece connecting it kinda melted.

[nogoodnames]

I am using RealHeat, it's a required mod for Realism Overhaul. Unfortunately, RO still hasn't completely adapted to the new heat system.

So after some further testing, it seems that this problem is not unique to that pod and actually affects all parts and all heat shields. Unfortunately, the pod I was considering with the built-in heat shield is only capable of low Earth orbit reentries. In fact, because of the heat shield bug, no pod is capable of a reentry from beyond low Earth orbit, except maybe the FASA Apollo capsule. It looks like I will have to rework my Mars mission. Instead of a direct reentry from interplanetary space, the interplanetary transfer ship will need to achieve orbit around Earth. This will require a lot more fuel, since an aerocapture is also likely a no-go. On the plus side, it means the transfer ship will be reusable, which is nice.

[BFEL]

You could try editing all the capsules to have ablator resource maybe?

[nogoodnames]

I could, but that's only part of the equation. The pod I want already has ablator, but I have no idea what it needs to behave the way I want during high speed reentries, and I don't feel like doing any extensive modding.

Edit:

Fix reentry (oops), DRE Mk1-2 pod heatshield.

Seems like maybe updating might help, but it would probably break some things too.

Doubleedit: Yep, that seems to have done it. I wish I had seen that changelog earlier. I still probably need to redesign the ship, but we'll see.

[fourpotatoes]

I've finally succeeded in making an SSTO spaceplane that can deliver a practical payload (in this case, 5000 units, or five Jebuchadezzars, of liquid fuel) to orbit, has sufficient delta-V for rendezvous maneuvers and deorbit with a comfortable margin, and has sufficient control authority to handle docking.

I've learned that practical spaceplanes need crazy TWR, need far fuel beyond the point I'd thought excessive, and need to be going in excess of 1.2 km/s at flameout. RCS Build Aid is also invaluable.

There are nineteen previous SSTO attempts in my saved ships, not including electric-prop (for Eve ascent) & vertical-launch experiments, a turboprop monstrosity, and an orange tank with a Mainsail, wings and cheap landing gear glued on.

[BigFatStupidHead]

Strange that you say they need high TWR. There was a big thread about how better spaceplanes have really, really low TWR. I think it was in the stock payload fraction challenge. On the other hand, congratulations on getting a SSTO spaceplane going. I still haven't done that since the new aero.


EDIT: I might be wrong. This happens.

[LoSboccacc]

otho someone did the math and best ascent is obtained going vertically and with a 2.0 twr - so basically a rocket.

[MagmaMcFry]

otho someone did the math and best ascent is obtained going vertically and with a 2.0 twr - so basically a rocket.

That ascent is optimal regarding energy efficiency, not fuel efficiency. A standard SSTO ascent is pretty energy inefficient, but remember that air-breathing engines are incredibly fuel efficient compared to rocket engines.

[nogoodnames]

After some modifications, the Ramses II has made a triumphant return to flight atop a replica SLS block 1B. Despite a few minor issues, the exploration upper stage was able to send it on a flyby of the Moon, followed by the capsule performing a near-perfect reentry.

Spoiler (click to show/hide)

It's competitor, a modified Big Gemini capsule, was deemed unsuitable for Beyond Low Earth Orbit reentries because of some changes with heat shield physics which reduced their ability to protect tall capsules. The crew is certainly happy with the roomier Ramses II, but it does mean that the required payload for the Mars crew transfer vehicle is going to be a bit higher than ideal. Hopefully no more problems crop up and I can start sending supply missions.


In other news, after watching one of Scott Manley's latest RP-0 playthrough videos, I made another attempt at creating a spaceplane capable of orbital reentry in RSS/RO. This odd wedge-shaped craft is what I came up with:

Spoiler (click to show/hide)

Basically, the idea was to use wings as a heatshield since they have twice the temperature tolerance of any other part. It almost survived reentry unscathed. Everything managed to hold together, except for that nosecone at the front. Unfortunately, that nosecone also holds all the RCS fuel. With no RCS and the centre of mass now shifted pretty far back, the thing became difficult to control. I pitched up a bit too far, stalled, and sent the thing into an unrecoverable tumble. But considering my previous attempts at reentry with a spaceplane, this one was a roaring success. I doubt I'll be able to incorporate the technique into an SSTO, though.

Anyway, I'm pretty sure Scott is using modified heat settings, since his craft get nowhere near as hot.

[Graknorke]

He has indeed turned the reentry heat down. He mentioned it in the 1st video I think.

[nogoodnames]

I managed to send the first presupply mission out to Mars this weekend. It's the lightest of my planned three, carrying a backup ascent vehicle and a mapping satellite.

Spoiler (click to show/hide)

Full Album

Boil-off for the NTR's liquid methane propellant was a bit more severe than expected, and I had to aerobrake to circularize the orbit. For the other supply missions I should be fine if I just include 25% more methane to compensate for the loss. However, this won't work for the crew vehicle since it is intended to stay in Martian orbit for around 2 years and then make the return to Earth. I'll have to switch to using either water or ammonia as the propellant. Both give lower specific impulses, but they should stay in storage indefinitely.

Right now I need to figure out a good place to land. Ideally, it would be somewhere flat and at a low elevation to make the most of Mars' atmosphere. Any suggestions?

[Aseaheru]

If you are using scansat than you can use its maps for elevation

[PTTG??]

1.0.5 is out.

Time to build deep-sea mining bases.

[BFEL]

1.0.5 is out.

Time to build deep-sea mining bases.

WAIT WHUT

[Aseaheru]

It does not appear to be around via the installer, so, while I dont know about you steam users, the rest of us need to download a clean install off the website.