The KiloTon mega-craft

[WarpPrime]

Challenge:  Launch a 1000-ton (or more) object from the surface of Kerbin into low Kerbin orbit, using STOCK PARTS ONLY. Please provide an image of your payload, an image of the rocket, and an image of the payload orbiting Kerbin. If you'd like, you can provide a craft file.

In text, include the mass of your rocket, the payload mass, and the TWR (thrust-to-weight ratio).

Least partcount (excluding the payload) wins. In the case of a tie, the highest TWR wins. Additional tiebreakers include: 

• Least massive rocket (excluding payload)
• Most massive payload

 

Leaderboard:

1. Lt_Duckweed - 1010.72 ton payload, 2818.28 ton rocket, 26 parts (5 for payload), TWR of 1.50
2. Pds314 - 1008.5 ton payload, 3394.64 ton rocket, 28 parts (6 for payload), TWR of 1.30
3. Snark - 1073 ton payload, 3438 ton rocket, 56 parts (78 for payload), TWR of 1.44
4. Spricigo - 1558 ton payload, 6164.9 ton rocket, 257 parts (67 for payload), TWR of 1.41
5. Hotel26 - 1993 ton payload, 5301 ton rocket, 279 parts (72 for payload), TWR of 1.89

Edited March 26, 2021 by WarpPrime
leaderboard updated

[Snark]

OK, I guess I'll toss my hat into the ring. 

Payload is 1073 tons.

Spoiler

 

The overall rocket is 4511 tons and 134 parts.  That's 56 parts excluding payload.

Spoiler

 

Here it is on the launchpad.  It's not going to win any prizes for elegant design, but it gets the job done. 

Spoiler

 

It can get to LKO with around 340 m/s of dV left in the final booster stage.  Here's the payload in orbit:

Spoiler

 

Rocket stats:

• Payload is 1073 tons in 78 parts.
• Rocket is total 4511 tons (3438 tons excluding payload).
• Rocket is total 134 parts.  56 parts excluding payload.
• Launchpad TWR is 1.44.

[WarpPrime]

47 minutes ago, Snark said:

OK, I guess I'll toss my hat into the ring. 

Payload is 1073 tons.

  Reveal hidden contents

 

The overall rocket is 4511 tons and 134 parts.  That's 56 parts excluding payload.

  Reveal hidden contents

 

Here it is on the launchpad.  It's not going to win any prizes for elegant design, but it gets the job done. 

  Reveal hidden contents

 

It can get to LKO with around 340 m/s of dV left in the final booster stage.  Here's the payload in orbit:

  Reveal hidden contents

 

Rocket stats:

• Payload is 1073 tons in 78 parts.
• Rocket is total 4511 tons (3438 tons excluding payload).
• Rocket is total 134 parts.  56 parts excluding payload.
• Launchpad TWR is 1.44.

Wow! Great job. I tried to build one myself - A 1.1 kiloton payload launched by a 3 kiloton rocket. Unfortunately, it exploded after 30 seconds of flight, so there go 500k funds, blowing away in the wind... XD

[Pds314]

Hmm ... I feel like cost optimization might be more interesting than partcount optimization since it won't incentivize "big dumb booster" as hard. Might give this a go anyway, though you know full well I'll be using a lot of the biggest tank in the game.

[Snark]

7 hours ago, Pds314 said:

Hmm ... I feel like cost optimization might be more interesting than partcount optimization since it won't incentivize "big dumb booster" as hard. Might give this a go anyway, though you know full well I'll be using a lot of the biggest tank in the game.

Actually, I think it would be kinda neat if the challenge had three separate categories, with three different leaderboards.  All of them with the same goal-- a kiloton payload delivered to LKO-- but they'd have three different victory criteria for craft-excluding-payload:

1. Fewest number of parts
2. Lowest mass
3. Lowest cost

(For example, like a dunce, when I first started this challenge, silly ol' me didn't read the instructions carefully, and I just assumed it was "lowest mass" and designed for that first.  Ended up with a rocket that got to LKO and was only 3384 tons on the pad-- that's 2311 tons excluding payload-- but it had over 400 parts in it... oh well, back to the drawing board)

[Lt_Duckweed]

4 hours ago, Snark said:

Actually, I think it would be kinda neat if the challenge had three separate categories, with three different leaderboards.  All of them with the same goal-- a kiloton payload delivered to LKO-- but they'd have three different victory criteria for craft-excluding-payload:

1. Fewest number of parts
2. Lowest mass
3. Lowest cost

(For example, like a dunce, when I first started this challenge, silly ol' me didn't read the instructions carefully, and I just assumed it was "lowest mass" and designed for that first.  Ended up with a rocket that got to LKO and was only 3384 tons on the pad-- that's 2311 tons excluding payload-- but it had over 400 parts in it... oh well, back to the drawing board)

Lowest mass would end up dominated by spaceplanes, as launching a 1000 ton payload would only require around 800 tons.

And if you are going by mission cost rather than launch cost spaceplanes would win that too.

[Snark]

2 hours ago, Lt_Duckweed said:

Lowest mass would end up dominated by spaceplanes

Sez you.

And anyway, even if it did... so?  Now there's a challenge.  I respectfully submit that designing a spaceplane to loft a 1000-ton payload is substantially more challenging than designing a rocket to do the same.

I just think it would be very enlightening to see what sort of solutions people would come up with for such a challenge!

2 hours ago, Lt_Duckweed said:

And if you are going by mission cost rather than launch cost spaceplanes would win that too.

I'd say launch cost is more interesting, personally, though of course it would be up to the challenge author.

[Lt_Duckweed]

54 minutes ago, Snark said:

Sez you.

And anyway, even if it did... so?  Now there's a challenge.  I respectfully submit that designing a spaceplane to loft a 1000-ton payload is substantially more challenging than designing a rocket to do the same.

I just think it would be very enlightening to see what sort of solutions people would come up with for such a challenge!

I built this a while back actually: 

1258 tons payload if I remember correctly.  In a few weeks when I'm back to my computer I may grab some more pictures and submit it as an entry.

[Bej Kerman]

I'll send digital cookies if you can make a reusable one without spaceplanes and using only SRBs.

[WarpPrime]

56 minutes ago, Lt_Duckweed said:

I built this a while back actually: 

1258 tons payload if I remember correctly.  In a few weeks when I'm back to my computer I may grab some more pictures and submit it as an entry.

Wow! Nice SSTO. However, technically, a spaceplane itself could be considered as a payload, so if you are using a spaceplane to launch a payload, please make sure that the payload is deployed from the plane instead of just launching a kiloton plane into space.

[swjr-swis]

23 minutes ago, WarpPrime said:

please make sure that the payload is deployed from the plane instead of just launching a kiloton plane into space.

Educated guess: the entire center column of tanks of that craft is the payload, seeing as it is attached by docking port (guessing it ends in one too). Would be pretty much exactly 1258 t, give or take 150kg.

[Lt_Duckweed]

7 minutes ago, swjr-swis said:

Educated guess: the entire center column of tanks of that craft is the payload, seeing as it is attached by docking port (guessing it ends in one too). Would be pretty much exactly 1258 t, give or take 150kg.

Bingo

 

Off the top of my head total takeoff mass was about 2400 tons.  Payload fraction was like 53% or so

Edited March 13, 2021 by Lt_Duckweed

[camacju]

8 hours ago, Lt_Duckweed said:

launching a 1000 ton payload would only require around 800 tons.

Try 600:

 

[Lt_Duckweed]

2 hours ago, camacju said:

Try 600:

 

I was assuming runway takeoff and no nervs or aero loveery on the part of either the launcher or payload, using a "normal" easy to use plane.  Its possible to exceed 63% by quite a bit when you really push the boundaries.   I've done 65% with a detachable payload, and Brad has done 70% calculated on the laythe+tylo ssto (I've only managed 69% calculated on my 11k ssto).

Edited March 14, 2021 by Lt_Duckweed

[Spricigo]

 

On 3/13/2021 at 6:00 PM, WarpPrime said:

However, technically, a spaceplane itself could be considered as a payload,

So, does my tanker counts as a valid entry?

Kataklysm

Spoiler

Mass(launchpad/orbit) 6 164.9t/1 558.0t , TWR1.41, 324 parts total with 67 in the upper stage.

 

[WarpPrime]

8 minutes ago, Spricigo said:

 

So, does my tanker counts as a valid entry?

Kataklysm

  Hide contents

Mass(launchpad/orbit) 6 164.9t/1 558.0t , TWR1.41, 324 parts total with 67 in the upper stage.

 

Yep! I will add you to the leaderboard.

[Hotel26]

I will enter my Titan 3 'Kakophony' for this.

Stats are:

    payload: 1,993t to LKO
    launch vehicle: 5,301t (7,294 - 1,993)
    part count: 279 (launch vehicle) + payload 72 = total 351
    TWR: 1.89 (launchpad, KER)

The real payload for me is: 308,000+ kallons of LFOX delivered to LKO, 1540t

     

(I'm entering Kakophony simply to publicize this machine, of course!  Now, nervously awaiting the entry of @Pds314...  )

Edited March 21, 2021 by Hotel26

[Pds314]

DLC is allowed right?

[Pds314]

5 hours ago, Hotel26 said:

I will enter my Titan 3 'Kakophony' for this.

Stats are:

    payload: 1,993t to LKO
    launch vehicle: 5,301t (7,294 - 1,993)
    part count: 279 (launch vehicle) + payload 72 = total 351
    TWR: 1.89 (launchpad, KER)

The real payload for me is: 308,000+ kallons of LFOX delivered to LKO, 1540t

     

(I'm entering Kakophony simply to publicize this machine, of course!  Now, nervously awaiting the entry of @Pds314...  )

Well, I'm not gonna beat your 27% payload fraction lol. Fortunately I don't need to. The goal is partcount, not payload fraction.

 

[Hotel26]

7 minutes ago, Pds314 said:

your 27% payload fraction

I think my personal yard-stick is total-fuel-to-orbit /  Mission-Controller-wage-kerbucks: the most fuel for the least launch.  But I know I am going to learn from your submission!

Edited March 21, 2021 by Hotel26

[Pds314]

Alright. May I present to you the "lol who needs aerodynamics" block 1b

You may see the flat faces and instinctively assume they are bent around into a pretzel to maximize node abuse. This is simply not the case. Those are legitimately big flat faces like on a 0.23.5 craft. Nobody said it needed to be sophisticated.

The payload, like the entire craft, is brutally simple. 5 entire parts weighing 1008.5 tonnes if the probe core is included. I would argue a probe core is a perfectly valid payload as almost all real payloads do have some sort of control mechanism, but it hardly makes a difference.

Partcount with payload: 52
Partcount without payload: 47
Payload: 1008.5 tonnes.
Launch mass: 4275.14 tonnes.
Mass without payload: 3266.64 tonnes.
Payload fraction: 23.59%
Launch TWR: 1.88 SL
Excess fuel in orbit: 82.5 tonnes.
Excess Delta-V in orbit: 227 m/s

VAB


On the pad... it's quite tall. 124 meters. Almost half of that is payload though.


Immediately we do a turn to the hard right. The TWR is so high we really don't need to worry about losing control or falling into the ocean. But we do need to not go straight up.


The raw power of 84 jets of fire. Pointing at Kerbol because it wishes it could to outshine it.


Nearly out of fuel.


Stage separation successful
|

Originally I was only going to have 3 engines on this stage but then it would have taken like 6 minutes to burn. 7 engines is much more powerful. I turn the gimbal down to prevent shaking and cosine losses.


And we have reached orbit. 82.5 tonnes of fuel left and 227 m/s Delta-V.


We threw ourselves into a higher Apokee with all that extra fuel.


Final shot of Kerbin.

[Pds314]

"lol who needs aerodynamics" block 1c

Same payload. Same fuel, but 8 fewer engines and 2 fewer plates. 110 tonnes lighter.

Partcount with payload: 42
Partcount without payload: 37
Payload: 1008.5 tonnes.
Launch mass: 4165.14 tonnes.
Mass without payload: 3156.64 tonnes.
Payload fraction: 24.21%
Launch TWR: 1.38 SL
Excess Delta-V in orbit: ~28 m/s

VAB


Stage separation


Circularized at 60 km and went half an orbit to Apokee. I regret nothing.

Almost there. We barely lost any energy from going through 2000 km of rarefied  atmosphere.


Final orbit. A bit higher than expect.


The majestic beauty of Kerbin from space.



 

[Pds314]

Hmm... So I kinda wonder what types of optimizations I could make?

Possible directions to take it:

1. SRBs? max-sized SRBs with no decouplers or nosecones provide 2949 kN/part of sea level thrust.. My lower stage has 7 tanks, 5 plates, and 15 engines, or 27 parts, and 56190 sea level thrust. Or 2081.1 kN/part. SRBs therefore have a considerably advantage in thrust/part. 41.7%. However, this comes at the cost of needing higher mass to achieve the same Delta-V. It is estimated that to achieve similar performance, somewhere between 23 and 25 SRBS would be needed. Thus saving 2-4 parts.

2. Plate compression: currently, 5 plates store 15 engines. If instead two of the outer tanks had plates and with 7 engines each while the central tank had an engine that was no on a plate at all, this could save 3 plates. 3 parts. If the original hexagonal tank configuration was restored and engines were clipped and translated from the top of the tanks to the base, this could save an additional plate, with 3 engines on the middle plate and  two engines directly attached to each outer tank.

3. Upper stage engine replacement. Rhinos have very high efficiency but somewhat lackluster thrust. Only 2 MN. Potentially adding an additional tank and switching out the 5 rhinos for 3 mammoths could save a part, however, it would need to make good use of the additional Delta-V from the extra tank, as this would eat into the lower stage performance.

4. Asparagus with all engines always burning? This could potentially save 4 parts off the lower stage if option 3 were taken.


All in all, I think getting the partcount down to maybe 32 is pretty doable. This would likely increase weight, however. Perhaps by as much as 1650 tonnes depending on which options are selected.

[Hotel26]

12 minutes ago, Pds314 said:

what types of optimizations I could make

A tour de force!  Well done.

[Pds314]

Alright. I made it sort of manually quasi-asparagus. Turns out that the decoupler integrated into plates doesn't allow for fuel flow, but I can still manually fuel transfer so that the second stage is almost full when separation occurs.

"lol who needs aerodynamics" block 2a

Partcount with payload: 33
Partcount without payload: 28
Payload: 1008.5 tonnes.
Launch mass: 4403.14 tonnes.
Mass without payload: 3394.64 tonnes.
Payload fraction: 22.90%
Launch TWR: 1.30 SL
Excess Delta-V in orbit: 39 m/s

VAB


Stage separation. Yeah... the engines are somewhat excessively offset. I probably could do it with them connected though.


Just prior to circularization.


Circularized at 75x74 orbit with 39 m/s to spare.


Extended to 120 km AP with remaining fuel and payload separated.  Upper stage doubles as a centrifuge lol.

These optimizations also mean that SRBs are no longer a good trade off. The lower stage is now 19 parts which means that SRBs barely even have a thrust/part advantage.