Mission improbable.

[RizzoTheRat]

Started my first foray in the world of 1.1, and without thinking accepted a contract to test a decoupler at an altitude of 3,000-9,000m, and a speed of 1,440-1,910m/s.  What parts available in the early game can cope with that?  A test vessel with a Mk1 pod sat on 4 hammers, with a Mk16 chute (rated 2500k) and 3 aerodynamic nose cones (rated 2400k) launched straight up exploded at about 12,000m and under 1,400m/s, so what the hell can hit 1,440m/s at 9,000m?

[Enorats]

This sort of thing is the reason I use Contract Configurator to disable all the part test, tourist, and survey contracts. They can just be totally unreasonable and rarely if ever rewarding without using an obscenely high funds reward modifier.

[bewing]

Maybe a hammer, an okto, a heatshield with no ablator, and the decoupler -- make sure you have turned completely horizontal by 5km or 6km. You certainly can't get to that speed straight up. You still won't have much time, either.

[James Kerman]

I would try a swivel and fuel as the first stage followed by a hammer second to get the speed.  I agree with bewing that you should get above as much atmosphere at reasonable speed before engaging the hammer.  I would use a probe core, battery and a reversed heat shield on the very top with a small amount of ablator.  I will try tonight and report results.

[bewing]

I think I like James' idea. Use a liquid fuel 1st stage to get slightly above 9km. Go into a shallow dive at maybe 500 m/s, stage, and hit the hammer.

[Hodari]

5 hours ago, RizzoTheRat said:

Started my first foray in the world of 1.1, and without thinking accepted a contract to test a decoupler at an altitude of 3,000-9,000m, and a speed of 1,440-1,910m/s.  What parts available in the early game can cope with that?  A test vessel with a Mk1 pod sat on 4 hammers, with a Mk16 chute (rated 2500k) and 3 aerodynamic nose cones (rated 2400k) launched straight up exploded at about 12,000m and under 1,400m/s, so what the hell can hit 1,440m/s at 9,000m?

Try putting a heat shield on the TOP of your vessel maybe?

[Empiro]

You can try to launch sideways, go up to close to 9000m, build up around 500 m/s, then use several SRBs to quickly boost up another 1000 m/s and hope you don't explode.

This is a tough contract, however, and is not one I would have taken in my own games.

[RizzoTheRat]

I've not played in a few months so it didn't ring any alarm bells until after I'd accepted the contract

I'm liking the climb and then dive idea, but control might be an issue.  My initial test vessel was just straight up to check if heating was an issue...it was.  My plan was to vertical launch and try and get a gravity turn to an apoapsis of 9km, but maybe I should aim a bit higher and then do more of the acceleration on the way down.

Unfortunately I'm very early in the game so the only control options I have at the moment are the Mk1 cockpit and Mk1 command pod.  I've got the Stayputnik as well but I'm using RemoteTech and don't have the Reflectron antenna yet so can't use that.

So I think the conclusion of this is try with a probe core sat on a hammer with a heatshield on the front, and loft the whole lot to horizontal flight at 9-10km with a liquid engine.  Presumably a heatshield on the front is going to be very draggy so will need more power and have a tendency to flip out?

Guess I'd better upgrade mission control so I can have more contracts, and then park this one for a bit until I've got more parts.

 

Edited April 27, 2016 by RizzoTheRat

[Streetwind]

One thing you have to admit though... this is a real part stress test.

[Broco]

18 hours ago, Enorats said:

This sort of thing is the reason I use Contract Configurator to disable all the part test, tourist, and survey contracts. They can just be totally unreasonable and rarely if ever rewarding without using an obscenely high funds reward modifier.

This is funny since I made most of my cash from the tourist missions

Just put a mining base on Minmus that delivers fuel to a station in Minmus orbit and you're set for countless tourist missions.

Here's my Minmus base with the Tanker (the smaller thing on the right, the green lights surround a landing platform):

And the orbital station:

Though I gotta admit that the refinery on Minmus as well as the station were a little bit oversized and underFPSed. Though 1.1 makes the refinery run at >10fps now.

 

 

I also waited for "build a new base at XY" missions to create single launch miner-tankers like this one which can make it back into orbit, refuel a spaceplane and land again:

The type of spaceplane I use fully utilizes the fuel bases. Once you have those in place (and you received money for it) you can start cashing in. Only costs you the fuel. Here's one example of planes I use:

 

I kinda like the idea of doing the same type of mission over and over again by trying to make is as efficient as possible, reducing weight, part count, adjusting flight profiles etc. Feels like... well... the real challenges of modern space programs.

Edited April 27, 2016 by Broco
adding images

[Plusck]

I can't open 1.1 right now (needed to get some old software working, and this OS doesn't like 1.1), but I tried in 1.0.5.

With a heatshield, OKTO and then single or multiple SRBs, the Hammer or BACC don't seem to have enough thrust to get up to 1400 m/s at that altitude, so a dive seems to be the only option. In level flight, the Hammer doesn't even seem to be able to reach 1000 m/s at that altitude without a nosecone (which would certainly blow up).

I tried with a Kickback and that worked: simply stick a quartet of elevon 1's (or that failing, the first controllable fins) at the back, then add four fleas underneath (1 in line and 3 surface attached - to do the job of launchclamps you don't have - you don't even need a decoupler), launch and use the fleas to get you near to 45° when you light the kickback. You still need to rise slightly above 9km before dropping, otherwise even the Kickback doesn't get up to more than 1400 m/s in level flight at that altitude.

[Enorats]

I generally prefer to use the contract system more for challenges and goals than a method for grinding funds. Most games I either significantly increase the funds reward modifier (making most contracts give 2 or 3 times what they cost to complete), or make gaining science points give funds with the Science Funding mod. Let's me not worry about funding too much while still have the parts of the career mode I do like.

 

[N_Molson]

The best one ever was to "land" tourists on Kerbol and back (for quite a ridiculous fee, of course). But I think it's fixed now

[James Kerman]

So I tried my method above with FAR however the best I could get was 1050m/s.  Most attempts ended with rapid loss of structural cohesion.  I have another idea that occurred to me on my way to work (it's actually how the first scramjet was fired) - launch straight up within a safe speed envelope and get up to 45,000 50,000m but save a hammer.  Once you begin descent experiment with firing the hammer at different altitudes and you should be able to accelerate through the thinner atmosphere to the target height - I would maybe try a flea to decelerate if you have to use a capsule however battery power may be an issue if you haven't unlocked electrics.  I am trying to do this using SRB's to keep costs down and the design is costing between 5,000-9,000 kredits.  I will try again tonight and post results.

Edited April 28, 2016 by James Kerman
more info

[Broco]

What about just achieving a high orbit and then set the periapsis to 9000 meters? With a heat shield you should survive the reentry.

But I agree, it's way too hard for that amount of cash.

[bewing]

I just took a couple tries at it, for the challenge. I came really close.

First try: I put a hammer-based rocket on the front end of a panther jet. My design cost 17310 kash.

I used the rounded 1.25m nosecone on the front -- since it has  a 2400 degree heat tolerance. For fun, I put a heatshield (no ablator) behind that.

Flew the panther up to a little above 9km, level flight, accelerated to 830 m/s. Lit the rocket. It accelerated in basically level flight to 1300 m/s and the nosecone blew the hell up. But the hammer couldn't push the remaining heatshield through the air that fast -- so the speed dropped to about 1220 m/s after the nosecone let go.

Added 4 small radiators to see if I could keep the nosecone from blowing. They added enough drag that the hammer rocket could only manage 1250 m/s, and it was clear from the nasty little red "overheat" gauge that the nosecone would have blown at 1300 just the same.

So, second try: remove the radiators, replace the hammer with a thumper -- expect the nosecone to blow at 1300, but maybe the thumper can accelerate the bare heatshield.

And in fact it can. But the poor panther really had more than it could handle to drag that thumper up to 10km. It made it, but I lit the thumper with little initial speed.

So, I lit the thumper; it accelerated in mostly level flight to 1300 m/s, the nosecone blew, the rocket continued to accelerate, and it reached 1450 with no further damage. However, I was unable to control the altitude properly at those speeds. And at 1450 m/s it takes very little time for the rocket to go from 9000 meters to 14000 meters altitude (or to 5000 meters, theoretically!). And then the rocket flamed out.

So, I think to make it work you're going to need to light a thumper in a dive from maybe 20km altitude. And you need to get the dive angle right, so that the thumper flames out just after it dives below 9km. But you really do have a very tricky test contract here.

 

[Plusck]

Well, it's possible with just 5 Hammers, two decouplers, three control fins, OKTO and heatshield (reduced to about 30-40% ablator):

Spoiler

This is a sandbox game, so the OKTO has all of the piloting options available. It's easier with prograde follow but basic SAS works.

I used 4 hammers (one central, three surface mounted) to go straight up from launchpad (SAS on), dumped them when they ran out, then lit the remaining Hammer on the way down, aiming straight down with SAS on again, at 32.5km. Only gives a split second at the right speed under 9000m - the lower atmosphere kills the speed very quickly.

[RizzoTheRat]

Some interesting approaches here.  Must say I hadn't thought about trying accelerating straight down, especially as I haven't got any decent probe cores yet still have Jeb at the helm and I've become a little attached to him over the years

I think the main thing I'm learning from this though is that I should read contracts more closely before accepting them.

 

[James Kerman]

Success
I play with FAR, if you play without you will need less fuel on the way up but you will get more speed on the way down.  I would try a Flea reversed and on top of the capsule to slow descent if you cant slow down enough to deploy parachutes (I built this variant and tested it - FAR decided I didn't need it and ripped it off the rocket before 9,000m however I did feel I had a fair margin of safety).

Design:
Mk 1 capsule + 2 radial chutes
de-coupler - this is the test part
Hammer
de-coupler
4x Fl-t 400s
Swivel
5,788 Kredits

Flight Profile:
Straight up full throttle
decouple LF tanks and reliant and coast till you descend
Pointy end down
Wait till descent speed is 250-300m/s and fire hammer
de-couple at target alt (9,000m)
Profit

I really like contracts that get me out of my Kerbal Komfort zone

Edited April 29, 2016 by James Kerman