Orbiting

[Kevin W.]

Well that explains it. He wasn't following the tutorial. Scott's rocket indeed has a LV-909 on the last stage, it is a LV-T30 though since it burns out just not long after 10km and there's plenty of control from the winglets.

*sigh*

Sorry for the slip-up. I've fixed it and I'm trying again.

[Johnno]

Sorry for the slip-up. I've fixed it and I'm trying again.

It happens. I'm really sorry for snapping at you.

[Kevin W.]

No harm no foul. I appreciate all the help.

[Vanamonde]

I got the impression you wanted to build your own rocket so I didn't suggest this before, but if you're getting this frustrated, how about trying my example rocket and walkthrough? http://forum.kerbalspaceprogram.com/showthread.php/25008-How-to-reach-orbit-and-a-rocket-that-can-do-it-a-walkthrough-for-newbies

[Kevin W.]

Well, that last flight went poorly. I added a second fuel tank to the second stage and upon separation, the second stage flipped over. Back to the drawing board...

[Kevin W.]

Well, I guess it all boils down to one thing now: the fine control. I understand the mechanics of how to get to orbit. I know what to do. I know the procedure. Now I just need to practice the turning. This part is going to take a while. Practice makes perfect, though.

One thing I'm noticing is that when I do the 10KM gravity turn and then let SAS re-activate by letting go of F, the SAS tends to snap me back westwards a little bit. I know it's supposed to be on 45 degrees. How far should I turn so the snap-back goes to 45 instead of even further back?

[sjwt]

In my attempts to boost my probe up to a high-enough altitude so its periapsis is above 70KM to establish a permanent orbit, my probe keeps flying into an escape trajectory.

To Circularise your orbit I like to recommend what I call 'Riding the AP'

Take your initial AP up to say 75kms, you do want your gravity turn to give you a nice long arch, not a short up and down trip.. the longer you get for when you reach 75kms the better. A supper excellent one would have your arch over more than half the planet, the longer the arch goes the easer it is to circularise.

Kill your engines when reaching a 75kms AP point, and cost until you are about 1 min out from the AP. At this point reface your craft so its pointing at about 40 Degreases to start off. Now when you reach 2 seconds out from your AP start to incress thrust untill you see the AP point staying the same constant distance from your ship.

Now its a balance game to ride the AP, you want the AP as close to the ship as possible, if the AP is too far away you have to slow down.. If its starting to fall behind your craft then you speed up.

If a slight change in thrust effects the AP point too much, you need to lower your noise closer to a HDG of 0, if you are going 100% and the AP is still closing you need to raise your HDG.

As you get closer to circularising smaller and small trusts at closer and closer to a hdg of 0 become stronger and stronger.. you will then see your AP start to really rush away, you should then be looking at killing your engines as it rushes away and closing on it agine for more bursts to get your nice and circular orbit.

Edited July 16, 2013 by sjwt

[Vanamonde]

the SAS tends to snap me back westwards a little bit.

The SAS isn't doing that; the fins at the base of your rocket are. When they are at an angle to your direction of motion, the airflow will push the tail of the ship back to conform to the direction of motion, which in this case returns you to your earlier attitude and therefore flight trajectory. You could move the fins up to reduce the effect, or over-ride it by actively steering until the prograde marker drifts down to where you want it to be.

[Kevin W.]

The SAS isn't doing that; the fins at the base of your rocket are. When they are at an angle to your direction of motion, the airflow will push the tail of the ship back to conform to the direction of motion, which in this case returns you to your earlier attitude and therefore flight trajectory. You could move the fins up to reduce the effect, or over-ride it by actively steering until the prograde marker drifts down to where you want it to be.

OK, I'll do that tomorrow after I get home from work. I'd do it now but I have to get to bed for an early wake-up tomorrow. Curse you opening shifts!

Also, is there a specific time when I should switch the indicator on the navball from surface velocity to orbital velocity?

[sjwt]

To Get your A1 into orbit, you need to swap the second engine for the LV909, im uploading a video I took of getting that into orbit for you.

Also "Also, is there a specific time when I should switch the indicator on the navball from surface velocity to orbital velocity?" just let it happen as it does, it doesn't normal effect much, its only an issue if the swap over happens and you don't notice it on a ship that is hard to control as is or is running on an extremely tight fuel budget.

Link for an orbit video, its about 16megs..

http://ksp.sjwt.org/2013-07-16/KSP.avi

Edited July 16, 2013 by sjwt

[rkman]

Take it one step at a time.

First use a rocket that you know works well and try get it into orbit.

Load the stock Kerbal X rocket and put an ASAS unit on it just below the top most decoupler.

Aim for about 45 degrees pitch at about 30km, and about 10 degrees at some 50 to 60 km. To get into orbit, horizontal speed is more important that vertical (upward) speed.

[Johnno]

Well, that last flight went poorly. I added a second fuel tank to the second stage and upon separation, the second stage flipped over. Back to the drawing board...

Well there's your problem. Don't add, don't subtract, use this EXACT design (scott manley's tutorial craft with an ASAS to help you). Don't skip over any parts or do it from memory, don't swap any parts for similar parts, use these EXACT parts. Once you learn to orbit and get comfortable with you can have all the fun you want tinkering, but use this EXACT craft. It's guaranteed to get you to orbit. If it doesn't, keep at it, don't swap anything out to 'improve' it.

Design:

Command pod Mk1 as starting piece. Add a Mk16 parachute on top of it. Below the pod add a TR-18A stack decoupler. Then the ASAS. Next a FL-T400 fuel tank. LV-909 Liquid fuel engine. TR-18A stack decoupler. FL-T400 fuel tank, FL-T400 fuel tank, FL-T400 fuel tank (three of them after eachother). At the very bottom a LV-T30 Liquid fuel engine. Click to 4x symmetry and add AV-R8 winglets to the bottom tank just above the engine.

Build it, don't exchange any parts whatsoever for similar ones. Just use the ones I listed. Done? Ok let's double check it, from the top. If need be doublecheck them visually from the parts lists.

Mk16 parachute, command pod mk1, ASAS, FL-T400 tank, LV-909 engine, TR-18A stack decoupler, 3x FL-T400 tanks, LV-T30 engine, 4 AV-R8 winglets.

Don't add launch clamps, don't add anything else, no antennas, no science equipment, no battery, no nothing extra.

BEFORE you click launch, here's how I want you to proceed once you launch, read these instructions twice or three times before launch, until you understand them. You'll have read them before as suggestions, you'll have heard them from Scott Manley, but keep reading them. I'll go over it again on the pad. You'll throttle to max, click T to engage ASAS and then launch using space. Nothing beyond that. Throttle up, ASAS, launch. Don't touch your steering controls before 10km. Just let the rocket do the flying, any miniscule change in course is fine. Don't worry about throttling down, we'll do this at 100% so there's one less thing to worry about. Keep reading before clicking launch; gravity turn.

Gravity turn: As you pass 10km altitude, press and hold F and then D, to turn eastward. Turn toward 45 degrees, once the rocket resists turn (around 40 degrees) release F. Your rocket will tilt back toward straight up, don't touch anything, let it. It'll tilt back nearly vertical, but it'll return. It'll tilt back a bit less, then return. Don't touch anything. Once it stabilizes around 40 degrees, it's likely to burn out so don't worry about it, don't touch anything but stage with space.

Light the second stage engine, let it stabilize without touching steering at all. Now press and hold F and gently tap D once or twice to turn closer to 45 degrees. Leave it there. Press M to bring up your map, pop up your nav ball at the bottom. Keep reading before launching.

Mouse over your AP marker and follow it, once it reaches 100km press X to turn off your throttle. You can also click the AP marker to have it show nonstop but don't worry about it for now, just move your mouse to view it. After you click X, click your orbit at the AP. Add manouver. Drag the circle with lines straight to the sides and up until you have a somewhat round orbit. Mouse over your PE, check that it's above 75km. Don't worry about making it perfectly round. Now press F and orient your ship toward the blue crosshair on the horizon (eastward). Then take your hands off the steering controls again.

Bottom of your screen gives you a estimated burn (around 1 minute) and a node in T - counter. If your est burn is around 1 minute, start to burn at T-30 seconds. Don't touch your steering controls, the blue marker will drift a bit, let it. Continue to burn until the delta-v counter reaches zero. Then press X. If you followed all this, you're in orbit.

Now here's some important information. It doesn't matter if you do your gravity turn perfectly at 10km or if you do it slowly and start at 11km. It doesn't matter if you turn to 35 degrees, 40 or 45. To aid your flight only use one finger on each hand, take your hand off the mouse entirely, you won't need it until map mode. If you need to press F and D, press F with one hand and D with the other, just two fingers.

Got it?

Click launch.

Throttle to max, press T for ASAS, leave full throttle on. At 10km hold F and press D. The rocket will resist at around 40, release F. Stage with space when the stage runs dry, correct gently to 45 if need be (or leave at 35 or 40), press M, wait for AP to reach 100km, press X. Manouver node on AP, drag circle with lines straight out and up (not angled down and cross inside), watch for PE to pop up, set it above 75. Turn toward blue marker (pressing D, it's on the horizon).

Wait until you're around half of your burn estimate before burn, burn full throttle without touching steering, even if blue marker drifts. Wait for delta-v counter to reach zero (or until you see your blue orbit line circle the planet and PE is above 75km) press X.

Go ahead and launch.

Repeat this until you reach orbit. Don't adjust anything designwise. At all. Repeat the launch and orbit steps I've written down. Re-read until you can recite the steps in your sleep if you have to. Don't change the rocket. It doesn't matter if you turn to 35 degrees, 40 or 45. It's fine. Don't panic about the rocket tilting back, it'll balance out toward where you set the ASAS, just let it. If it resists turn don't force it, leave it at 40 degrees and don't try for 45. You'll get to orbit anyway.

Just repeat this until you're in orbit. There shouldn't be need for clarifications, or changes. If I've made a blatant error someone else will point it out, Kevin you just go for orbit. Repeat this 'guide' without changes until you're in orbit.

Everyone's trying to help you but you keep changing things or panicking. Follow my guide here and you'll get to orbit, using two fingers, without changing throttle, barely without changing directions. The gravity turn doesn't have to be perfect and before your orbit burn you have plenty of time to set a manouver node and to turn toward it. And you don't have to chase the blue marker, you'll get to orbit.

No further advice or help should be needed, re-read this post and re-launch until you're in orbit.

[SRV Ron]

Better to start the gravity turn in several small step starting at 5,000 meters and complete it by 25,000 meters then to do it in one step. Shut down and coast when you reach desired apogee, then burn horizontal just short of apogee to circularize. To stop the snap back motion, wait until the motion stops on its own or apply a little counter rotation with the A key until it stops before returning SAS control to your rocket. Be sure that Window's "Sticky Keys" are turned off so it doesn't interrupt you pulsing the D key doing your gravity turn in gradual steps.

Stabilizing fins at the base will make it harder to do that turn in one broad step on some designs. You will need several small turns and reactivate SAS when the motion stops in spite of you using the D key continuously, then repeat the maneuver as needed until you get the desired angle on the Nav Ball.

Edited July 16, 2013 by SRV Ron

[stupid_chris]

If I can suggest something, here is the way I learned:

It'S controversial around these parts, but MechJeb. I'm not telling you to download MechJeb and use it to magically solve your problems. When I downloaded MechJeb, I had do things while I just sat and watched. Just by watching how it does, you can learn so much. From efficient ascent profiles to how to set your maneuver nodes, all the way to how to land. Really, simply sitting back and watching it go learned me more about this game and how to play than any tutorial ever did.

After I learned, I stopped using it and started doing my stuff myself, and with barely no practice, I was already pretty good from simply watching. Since then I started using it rather often again because it turned out for me that the piloting part of the game was the one I enjoyed the less, but really that's up to you to decide. Really, MechJeb is an incredible tool. From multiple useful information to advanced in game help, it can do a lot. It'S up to you to decide what you want in the end.