We will not weaponize space

[ckellingc]

My friends and I have come up with a strange, yet addicting challenge I wish to share with you.

1. Get into orbit.

2. After at least 1 complete rotation, you are to use a single solid fuel engine and blast yourself towards the launch pad.

3. Closest missile to reach launch pad wins.

RULES:

Sunday's pack ok, but the small (stock) solid fuel engine is to be the final deorbiting burn that propels you toward the tower

No parachutes... missiles don't use parachutes.

Orbit can be any altitude

HINTS

When we have been doing this, we orbit usually 3 times to line ourselves up with the tower. A bunch of SAS and wings are highly recommended to ensure a straight orbit.

[Ntmoore19]

I can't wait to see someone orbit at 1K and do this easily.

[ckellingc]

If they can do that with sundays pack, go for it.

[DoctorEvo]

This sounds like fun.

Can I put frickin' laser beams on mine?

[Itchono]

hmm an ICBM program???

If so, WE GOTTA MAKE WARHEADS!

[DoctorEvo]

Wow, this is friggin' hard.

One question; are we allowed to use a LFE for our deorbit burn and save the SRB for terminal guidance?

[ckellingc]

The original plan was to use the SRB's for the deorbit burn and targeting. You can make a 2 stage SRB for deorbit burn and targetting if you would like.

[smokles]

lol, I remember you and ikroth discussing that ckelling

[foamyesque]

This sounds like a challenge that will require mathematics.

[Xenoc]

Hmmmm. Interesting...

To the Vehicle Assembly Building! For science!

EDIT: After a highly elliptical orbit (500km apogee, 100km perigee) I fired the rocket too late. Definitely achievable (if horrifically difficult) though. Shame it takes an hour to get up and orbit before the 25 seconds of excitement ;D

[Spiz102]

Do we get bonus points for massive deceleration on reentry achieved by coming in straight down really really fast to allow us to penetrate through any missile defence systems deployed close to the KS... I mean the target.

[MaxSchram]

How do you handle the fact, that the SRB + Pod overheats pretty quick outside the atmosphere?

[DoctorEvo]

How do you handle the fact, that the SRB + Pod overheats pretty quick outside the atmosphere?

That's my secret. ;P

[foamyesque]

How do you handle the fact, that the SRB + Pod overheats pretty quick outside the atmosphere?

Winglets.

I'm tempted to take a SFB, weight it down with SAS until its dV is something sane, and try a direct Hohmann insertion, but I think it would probably be simpler to adjust into a very low (36km) orbit, fire the SFBs straight down/backwards for a moment, and then helicopter until burnout. =/

[millsw]

Winglets do it.

[ckellingc]

I just came PRETTY close, but couldn't quite see the station. GRRR

[MaxSchram]

Who has read my last posts may has recognized that i like to calculate and simulate things. I also tried it with this challenge and came to the following idea:

The only thing that can't be calculated properly is the atmospheric influence and i wanted to get rid of that problem. So i established an orbit, where the orbital velocity exactly matches the delta-v the last stage (Pod, SAS, SRB) would provide. It's at 2053831.93m altitude and 1153.39m/s speed. Than i waited till the spacecraft was, as exactly as i could see, above the space center and burned the SRB. Be doing so all kinetic energy was removed and the rocket was falling towards the target. It didn't hit, but taken the enormous orbit distance into account, it was pretty close.

1st: Launch.

2nd: First orbit at 158km.

3rd: Target orbit after Hohmann Transfer at 2085km (missed the target orbit, but could readjust the speed)

4th: Burning the SRB 20 minutes later.

5th: Atmospheric entry around 40 minutes later at 2904m/s. (space center is near the nav ball)

6th: Impact, with space center in view distance.

[DoctorEvo]

The only thing that can't be calculated properly is the atmospheric influence and i wanted to get rid of that problem. So i established an orbit, where the orbital velocity exactly matches the delta-v the last stage (Pod, SAS, SRB) would provide. It's at 2053831.93m altitude and 1153.39m/s speed.

Ooh... that's good. That's really good. I'd pretty much given up hope of killing my velocity exoatmospherically and dropping vertically... I didn't even think to try it at apokee like that...

[DoctorEvo]

Launch:

[orbit and deorbit goes here](forgot to screencap 'cause this was like my fourth attempt)

Come to papa...

Ooh, you're mine now...

QUIT FLYING AND GET DOWN THERE, DANGIT

MONEY, BABY!!

(I'm actually surprised my first stage reentered. I separated RIGHT AFTER orbital injection and didn't touch a thing until I deorbited. Though I did have an extremely low perikee...)

Do I win?

[CarolRawley]

Jeez, DoctorEvo. Have you been dumping too much radioactive waste in the ocean?

[foamyesque]

Why the long tank stack on the rocket, Evo, instead of putting them under the tricoupler? Balance?

[DoctorEvo]

Why the long tank stack on the rocket, Evo, instead of putting them under the tricoupler? Balance?

Yup, and structural. This way I could use less winglets and I didn't have to worry about three long stacks wobbling around and crashing into each other.

Though there were some odd lengthwise wobbles in response to having control inputs way out on the ends of such a skinny stack...

[foamyesque]

Eh, four tanks is isn't that long a stack, but you'd have flip trouble with just a solid up top.

O'course, you could compromise; three tanks above, three tanks each below, strut the bottom three together, apply winglets. R8s should give you the control authority to correct tricoupler roll and to spare. =/

[DoctorEvo]

Eh, four tanks is isn't that long a stack, but you'd have flip trouble with just a solid up top.

O'course, you could compromise; three tanks above, three tanks each below, strut the bottom three together, apply winglets. R8s should give you the control authority to correct tricoupler roll and to spare. =/

I almost did that, but with a SINGLE tank below, because that would let me mount the winglets even lower so that they overlapped the engines some. But this is what I went with, and it worked, so eh.

[frenchie16]

Plan: calculate exactly how much delta-V a single SRB with command pod and SAS has, get into whatever orbit has an orbital velocity of exactly that, and then use your SRB to stop dead right over the launch pad. You\'d need to time it perfectly, the orbit would probably be an insanely-high one, and it\'s very hard to be precise about when you are over the pad...