Stock Payload Fraction Challenge: 1.0.5 Edition

[Red Iron Crown]

I've tidied up the OP a bit and updated it to include Nefrums' incredible staged airbreathing entry.

[parzr]

Can the payload be fuel that is sloshed around to balance the craft but otherwise unused?

[Red Iron Crown]

43 minutes ago, parzr said:

Can the payload be fuel that is sloshed around to balance the craft but otherwise unused?

Only if it stays within the payload tanks. I.e. you could launch with partially-filled, deactivated tanks as payload and transfer fuel among them, but you can't transfer payload fuel into the lifter or lifter fuel into the payload.

[parzr]

ok, have to move my engines to surround the tank more then its more a look thing for my craft.

Edited December 17, 2015 by parzr

[Temstar]

For recoverable rocket, can the recovery of the launch vehicle be conducted in multiple phases instead of in one go?

As in, instead of a SSTO rocket that goes into orbit, release payload then come back all in one piece. Can you have a mission architecture where a SSTO rocket goes into orbit, release the payload then separate into multiple sections where each section then makes its own way back to KSC?

I have a design like that that's nearly completed.

[Red Iron Crown]

@Temstar Yes, you can do multiple recoveries as long as everything makes it safely back.

For clarity: No stage recovery mods are permitted.

 

[Temstar]

Since no one is putting their hands up for recoverable rocket category I figure I'll get us started:

Presenting Hurricane Duo Block II:
http://forum.kerbalspaceprogram.com/index.php?/topic/128674-stock-105-hurricane-launch-vehicle-family/

Spoiler

Vehicle on the launch pad, 624.402 tons at lift off.


Starting gravity turn at 600m


Vehicle at 10,000m, pitching down to 40 degrees above the horizon, TWR is at 1.90 and increasing rapidly.


Peak heat load during ascent just after MECO, AP is now at 75km. Starting coast phase.

Circularisation burn just before the AP.


75km x 75km orbit achieved.


Payload release, payload mass is 97.095 tons. I kept ET attached to one of the Aurora boosters because I wanted to keep the ET battery full for reentry.


ET detach from booster and beginning deorbit burn after orbit once around.


Peak heat load during ET reentry


ET parachute fully deployed, it's capable of both splashdown and landing on dry land.


ET after safe splashdown near the Island Airfield, ready to be recovered.


Aurora 1 deorbit burn after 2 orbits, you can see Aurora 2 and payload some distance away.


Aurora 1 experiencing peak heat load during high AoA reentry.


Aurora 1 approaching KSC runway with air brakes deployed.


Aurora 1 shortly before touch down.


Aurora 1 safe on the runway ready to be recovered.


Aurora 2 beginning deorbit burn, the thing next to it is the payload.


Aurora 2 approaching KSC.


Aurora 2 safely back at KSC.

97.095 / 624.402 = 15.55% payload fraction by my calculation.

Should be plenty of opportunity for increasing that payload fraction too, although this is first and foremost intended as an operational vehicle to achieve low cost/ton to orbit. This particular vehicle will give you $478.28/ton to orbit or more depending on how good you are at landing the ET near KSC.

[Red Iron Crown]

Well done, @Temstar, your recovery method is fairly brilliant! Added to the top of the board.  

[Temstar]

I got another one for recoverable rocket, Hurricane Trio Block III:
 

Spoiler

Whole stock on the launch pad, 942.350 tons


Gravity turn at 10km.


Circularisation burn


Payload release, payload is 146.795 tons


External Tank deorbit burn.


External tank, high alpha reentry.


External Tank, just before touch down.


External Tank, safely stopped on the runway ready to be recovered.

The three Aurora Winged Boosters are 100% identical to my previous entry so I won't go into too much detail about their deorbit burn or reentry.


Aurora 1 approaching KSC.


Aurora 1 ready to be recovered.


Aurora 2, approaching KSC for an evening landing. It use to take me a few quick loads to get the landing down pat, but now I've done it so many times I was confident to both get it down in one go and attempt a night landing. These winged boosters are still not exactly gliders but they are also well behaved enough that landing them is not that much different from landing a regular airplane, despite the CGCP mismatch (ie CoM all the way at the back with that heavy engine and no cockpit).


Aurora 2 on the runway ready to be recovered.

Aurora 3, approaching KSC in the dead of the night.


Aurora 3, ready to be recovered.

146.795 / 942.350 = 15.57%. Only a hair higher payload fraction than my previous entry. But I thought it was worth entering this as it has a much more advanced ET recovery system which means now the whole launch vehicle is 100% recoverable. I haven't run through the numbers but I suspect since the fuel is now the only cost we're looking at under $400 per ton to orbit, so certainly we now have a rocket with the same ballpark cost per ton to orbit figure as your garden variety SSTO spaceplanes.

[Red Iron Crown]

Great design, Temstar (like the others in your thread, it's a great system). Added to the leaderboard.

[Nefrums]

I'll give you some competition in the reusable rocket category.

Here is my simple reusable two stage rocket: RLS mk1:  

Payload fraction: 20,80%

 

Edited December 31, 2015 by Nefrums

[Red Iron Crown]

Well done, Nefrums. That's some minimalist recovery equipment, great use of a fully recoverable two-stage profile, and a clever trick to disable the battery on the upper stage until control was needed, saving charge. Added to the board.

[Nefrums]

I decided to test how much you can lift with a single vector engine, here is the result:

Payload fraction: 26,84 %

[superstrijder15]

is it allowed to have fuel tanks as payload and like use half of that fuel?

[Red Iron Crown]

8 minutes ago, superstrijder15 said:

is it allowed to have fuel tanks as payload and like use half of that fuel?

No, that would be equivalent to counting some of the lifter's tank mass as payload. Fuel may not be moved between payload and lifter.

[Nefrums]

My single vector rocket "Long Stick" was meant as an entry in the Rocket Only category.   Will you add it? 

 

I have been trying to beet the reusable score for a while and finally done it. With the "Stingray Mk12"

Payload fraction: 56.04%

It has 6 rapiers and one Nerv.

 

 

 

 

 

 

 

[Val]

5 hours ago, Nefrums said:

My single vector rocket "Long Stick" was meant as an entry in the Rocket Only category.   Will you add it? 

 

I have been trying to beet the reusable score for a while and finally done it. With the "Stingray Mk12"

Payload fraction: 56.04%

It has 6 rapiers and one Nerv.

 

 

 

 

 

Great job, @Nefrums

I like that nosecone you created. Genius! 

[Nefrums]

6 hours ago, Val said:

Great job, @Nefrums

I like that nosecone you created. Genius! 

Thanks!

The "nocecone" consists of a 2.5m faring, 2 small ore tanks and a shielded docking port.  I got better performance from this then I got from a C7 adapter and a shielded docking port. 

The shielded docking port still have terrible drag, but it is the only part that can handle the heat.

It was a bit tricky to balance the ships CoM/CoL both with full fuel tanks + payload and with empty tanks without payload.

 

Edited January 5, 2016 by Nefrums

[Bomaye]

How on earth do you guys get 1600m/s at 18 000m without overheating, in 1.0.5 I can only do 13-1400ish???

[Nefrums]

1. Keep the ship pointing very close to prograde 
2. have a part that can handle the heat on the front of the ship.  I have only found two parts that can do this: the shielded docking port and a heat shield.  Both have terrible drag, but the docking port is slightly better

[Red Iron Crown]

@Nefrums Sorry for the delay in reviewing your entries, I've added both of them to the board. Well done, as always.  

Will anyone step forth to knock Nefrums off the top of at least one of the boards? XD 

[Hexlord]

Just to clarify, when you say the decoupler must stay with the lifter, does this simply mean I place the decoupler in reverse? Or am I over thinking this and a normal staged decouple is accepted?

[Val]

1 hour ago, Hexlord said:

Just to clarify, when you say the decoupler must stay with the lifter, does this simply mean I place the decoupler in reverse? Or am I over thinking this and a normal staged decouple is accepted?

You're over thinking it. It's just the normal way where the decoupler stays with the Rocket and not count as part of the payload. 

[tewpie]

Awesome job @Nefrums, that's a creative entry .

Now that I'm kind of off my Fallout binge I'm back to playing KSP.  Just dug up an optimized revision of my previous design that I never published, so stay tuned .

Edited January 7, 2016 by tewpie

[Nefrums]

2 hours ago, tewpie said:

Awesome job @Nefrums, that's a creative entry .

Now that I'm kind of off my Fallout binge I'm back to playing KSP.  Just dug up an optimized revision of my previous design that I never published, so stay tuned .

I also spend a few weeks in that binge 

Locking forward to you giving me a reason to continue development of my entry    

As i had ~90 dV left in orbit I think that I could just add some more ore in the payload. And the nosecones I used for the rapiers might not be the best, so I feel that I still have some room for improvement.

Edited January 7, 2016 by Nefrums