I need RO recommendations...

[XpertKerbalKSP]

Hello fellow Kerbonauts!

I just installed RSS and RO and I really enjoy it. But there are some things that I still need "fixing", let's say.

One of the things I really need fixed is fuel tanks and engines. The engines that RealFuels provide are terrible. They're not really designed to have a specific function, which is what I need on my rockets. So can anyone recommend a mod that RO goes with that adds engines which have a more specific function. For example vacuum engines should consume low fuel but have a relatively hight thrust.

Thanks!

[legoclone09]

Well, on the RO main thread it has all of the supported mods, like Lack's Stock Extension, Tantares, Raidernick's stuff, and lots of other stuff I forgot.

[NathanKell]

@XpertKerbalKSP I think you may not have adjusted to RO then. While MOAR BOOSTERS is a common approach in KSP, it really doesn't translate well. Once you get above a couple thousand meters per second, you can toodle along at very low thrust, say with an upper stage with a burn time of 8 minutes or more. Once you're in orbit you're no longer suffering gravity losses, so even lower TWR is fine. The current EELVs, optimized for putting payload on geostationary transfer orbits, have upper stage burn times in the 10-20 minute range. That's even more true for going to the Moon or other planets (my direct Saturn injection will feature 15 minutes across two hydrolox stages, in addition to a 10 minute flight into orbit)

What roles do you need high-thrust vacuum engines for? (And what qualifies as high thrust?)

[stratochief66]

High thrust engines weigh more, but you can use them. When you need/want moar thrust, you can use a cluster of engines instead. For example, a cluster of 4 RL-10 engines (which are included in RO and a number of RO compatible mods) delivers ~400 kN of thrust and an ISP in the range of 450s. The largest upper stage engine I'm aware of was the J-2 used on the Saturn V, which has a thrust of ~1000kN and an ISP of around 424s. If you have a problem that can't be solved by a cluster of J-2 engines, I dare say you are doing something wrong.

 

But as NathanKell says, real world rockets (which RO allows you to reproduce, if you want) use low thrust upper stages for a reason. Think of it has hauling around dead weight. More high thrust engines save you burn time, but they are effectively non-fuel mass you have to push around, making a stage less efficient. But if you want to sacrifice the efficiency for shorter burns, clusters of RL-10 or J-2 engines should suit you well. Both of those engines are in the FASA mod, as well as the SSTU mod.

[NathanKell]

Well, there's the never-made M-1 engine, that's supported too. And the NK-43 is a vacuum engine with ~2MN thrust.

Oh, slight correction, sorry. That burn I describe is for a direct-flight (no gravity assist flybys) Mercury orbiter. A Saturn flyby probe only needs a ~7.7km/sec ejection burn for my next window, I can do that just with a single hydrolox stage (8 minutes).

[XpertKerbalKSP]

6 hours ago, NathanKell said:

@XpertKerbalKSP I think you may not have adjusted to RO then. While MOAR BOOSTERS is a common approach in KSP, it really doesn't translate well. Once you get above a couple thousand meters per second, you can toodle along at very low thrust, say with an upper stage with a burn time of 8 minutes or more. Once you're in orbit you're no longer suffering gravity losses, so even lower TWR is fine. The current EELVs, optimized for putting payload on geostationary transfer orbits, have upper stage burn times in the 10-20 minute range. That's even more true for going to the Moon or other planets (my direct Saturn injection will feature 15 minutes across two hydrolox stages, in addition to a 10 minute flight into orbit)

What roles do you need high-thrust vacuum engines for? (And what qualifies as high thrust?)

Well, you're quite right, I only just started playing RSS/RO like 5 days ago, so I'm not Scott-Maney-professional. I Haven't even been able to get into orbit yet...

Well, I'd need some MEDIUM thrust MEDIUM efficiency engines, actually. Maybe 200kn of thrust and 30 units per second is good for me.

[NathanKell]

Ah, sorry, I don't think in terms of flow rate. Also, because density is not the same for all propellants, flow rates will vary widely for the same Isp. Let me take a different tack: How much payload are you trying to place in orbit?

[XpertKerbalKSP]

15 hours ago, NathanKell said:

Ah, sorry, I don't think in terms of flow rate. Also, because density is not the same for all propellants, flow rates will vary widely for the same Isp. Let me take a different tack: How much payload are you trying to place in orbit?

Can't even launch a rocket with nothing on it.... I've tried looking at different tutorials and guides, but I just can't seem to do it. I either run out of DeltaV on my last stage or I go past my Apoapsis and re-enter.

I tried doing dry runs of my launchers (with no payload), tired increasing delta v, but I just can't seem to do it. Once, I had like 12,000m/s dv and my first stage of 1.6 TWR initially and my second stage of 2.0 TWR initially, but no,  I go past my AP. Can you peles give me some recommendations about my TWR and DV requirements and where to point at what time?

[Blue_Eagle7]

To reach orbit try raising your AP with your first stage to 150-200km and then keep that AP with your second stage burning not at the prograde marker but just looking at the AP height. Using so high TWR on second stage can be a problem if you start it too soon (it's much harder to control the AP and the final orbit)

[XpertKerbalKSP]

50 minutes ago, Blue_Eagle7 said:

To reach orbit try raising your AP with your first stage to 150-200km and then keep that AP with your second stage burning not at the prograde marker but just looking at the AP height. Using so high TWR on second stage can be a problem if you start it too soon (it's much harder to control the AP and the final orbit)

Ahh, I see. I've always been trying to use my atmospheric location to point ( if that makes sense ). I'll try doing this when. I play RO again. Thanks!

[CitizenVeen]

You want To do a gravity turn.

Once you reach speed of 50 m/s pitch over a few degrees East. Then keep following your prograde marker. You will raise your AP while gaining horizontal speed. When you are at 45 degrees, tour AP should be arround 80-90 km. When you reach your AP it should be arround 200km (your prograde is horizontal then). Try To not let your vertical speed drop To low (not more then 150 m/s downwards).

My first stage usually starts at 1.3 SLT, with a max TWR of ~5. My second stage usually starts at just below 1. Thats more then enough. Youll need atleast 9.4 km deltaV. If you have like 10 km Dv you can safely put tour AP at 300km zo you have alot of time after reaching tour AP to reach Orbit.

Good luck!

[CitizenVeen]

@XpertKerbalKSPI made a step by step imgur guide for getting to LEO in Realism Overhaul (was making it anyways for someone else):

http://imgur.com/a/JNHCi

Please let me know if it helps, or if anything is unclear.

[Matuchkin]

On 27/02/2016 at 6:57 PM, XpertKerbalKSP said:

Hello fellow Kerbonauts!

I just installed RSS and RO and I really enjoy it. But there are some things that I still need "fixing", let's say.

One of the things I really need fixed is fuel tanks and engines. The engines that RealFuels provide are terrible. They're not really designed to have a specific function, which is what I need on my rockets. So can anyone recommend a mod that RO goes with that adds engines which have a more specific function. For example vacuum engines should consume low fuel but have a relatively hight thrust.

Thanks!

1. GET PROCEDURAl TANKS AND FAIRINGS OR YOUR ROCKETS WILL BURN

2. Get AIES, Tantares, and Tantares LV. Apart from providing extremely good bases for satellites, they provide amazing orbital engines that cannot compare with anything else.

3. Get Mechjeb. Otherwise, you'll have a really hard time launching, docking, etc. Yes, I know what you're thinking, but think of MJ as an avionics system.

Now for some small tips for building rockets in RO.

1. Think simplistic. Look at all the real life rocket designs- a simple column-like lower stage, and an extremely small upper stage. Separate your launcher into two halves- the part that gets you some initial speed (launch stage) and the part that gets you to orbit (stage 2). You can also add a 3rd stage that will generally do all the work in getting you places, after you're in orbit.

2.  For the launch stages, use the weakest launch engines possible (those usually have the best dv), and make your TWR really small. Though I sometimes stray past 1.30, I go with 1.06-1.09 TWRs. Power doesn't matter, as long as you can lift yourself and have enough DV. The speed will come later, as the rocket becomes lighter.

3. For the 2nd stages, use a weak, efficient engine. I prefer the (AIES) RL-60, and, in heavier cases, the (AIES) AJ-10.

 

So here's how you think (to summarize):

- Stage 1: Gets you out of the atmosphere, high TWR, less DV

- Stage 2: Gets you to orbit. TWR approximately 0.90. More DV.

- Stage 3 [Optional]: Gets you to your target planet/ship. Tiny TWR, usually within 0.20. A LOT of DV.

 

The lander/ probe you get to your target (assuming you're not putting up an Earth orbital Satellite will probably have its own stages, but I consider that as another part of the craft.

Edited February 29, 2016 by Matuchkin

[regex]

Just for reference, any R-7 based launch vehicle will have a very easy and forgiving manual launch.  That is, you can make mistakes and still get to orbit.  A Vostok-alike is especially good for 5-ton LEO operations and great for beginners, you can easily find stats on the general layout on the web and RP-0 has the RD-107/108 engines.  Or grab Raidernick's Soviet Rockets pack and try it out.  The LV minus spacecraft is gold and far from the low-TWR snooze-fest that an Ariane 5 or Saturn V offers.

Edited February 29, 2016 by regex

[XpertKerbalKSP]

2 hours ago, Matuchkin said:

1. GET PROCEDURAl TANKS AND FAIRINGS OR YOUR ROCKETS WILL BURN

2. Get AIES, Tantares, and Tantares LV. Apart from providing extremely good bases for satellites, they provide amazing orbital engines that cannot compare with anything else.

3. Get Mechjeb. Otherwise, you'll have a really hard time launching, docking, etc. Yes, I know what you're thinking, but think of MJ as an avionics system.

Now for some small tips for building rockets in RO.

1. Think simplistic. Look at all the real life rocket designs- a simple column-like lower stage, and an extremely small upper stage. Separate your launcher into two halves- the part that gets you some initial speed (launch stage) and the part that gets you to orbit (stage 2). You can also add a 3rd stage that will generally do all the work in getting you places, after you're in orbit.

2.  For the launch stages, use the weakest launch engines possible (those usually have the best dv), and make your TWR really small. Though I sometimes stray past 1.30, I go with 1.06-1.09 TWRs. Power doesn't matter, as long as you can lift yourself and have enough DV. The speed will come later, as the rocket becomes lighter.

3. For the 2nd stages, use a weak, efficient engine. I prefer the (AIES) RL-60, and, in heavier cases, the (AIES) AJ-10.

 

So here's how you think (to summarize):

- Stage 1: Gets you out of the atmosphere, high TWR, less DV

- Stage 2: Gets you to orbit. TWR approximately 0.90. More DV.

- Stage 3 [Optional]: Gets you to your target planet/ship. Tiny TWR, usually within 0.20. A LOT of DV.

 

The lander/ probe you get to your target (assuming you're not putting up an Earth orbital Satellite will probably have its own stages, but I consider that as another part of the craft.

Oh wow, that was a very detailed reply. Thanks a lot! Now I can hopefully make some progress and not kill my kerbals.....

[XpertKerbalKSP]

3 hours ago, CitizenVeen said:

@XpertKerbalKSPI made a step by step imgur guide for getting to LEO in Realism Overhaul (was making it anyways for someone else):

http://imgur.com/a/JNHCi

Please let me know if it helps, or if anything is unclear.

Great tips there, mate! Thanks! 

[Matuchkin]

59 minutes ago, XpertKerbalKSP said:

Oh wow, that was a very detailed reply. Thanks a lot! Now I can hopefully make some progress and not kill my kerbals.....

Thanks! I also need to say: Try to develop a few series of launchers. Designate them, and scrap the ones that can't fulfil a broad enough range of tasks. That way, you'll have a very quick and nice way to launch payloads, advancing you in-game by a massive amount when your rockets get better.

By the way, @regex stated that an r-7 based launcher will be manually forgiving. I do not recommend that for beginners, for these reasons:

1. It is much more quick, simple and efficient to build a launcher based on the present Delta and Atlas rockets. My first series, though, was originally based on the PSLV, made in India.

2. It is probably more interesting to create one's own KSP launcher series, without relying on someone else for your own tasks. Takes all the fun from RO.

I also need to say that, with Procedural Fairings, engine sizes don't matter. I usually take the 1 meter RL-60 that I use on my 2nd stages, and put them on a huge fuel tank (3m for my first launcher series, the "Mu", and 5m for my second launcher series, "HULS" [in developement]). Then I cover it up with a fairing, and it blends amazingly, like an actual rocket.

As well as that, there are some exceptions for my statement on the use of launch engines. The SSME is an orbital engine, yet I use it on the 1st stage of my HULS 1 launcher, my best launcher yet. Other orbital engines are less fit for launches, though.

Anyway, thanks for the comment!

Edited March 1, 2016 by Matuchkin

[Matuchkin]

1 hour ago, XpertKerbalKSP said:

and not kill my kerbals.....

Umm, yeah. On that topic- don't start with kerbals. Use light satellites (comsats, weather satellites, mapping satellites, etc) NASA runs on those, and you will probably end up with extremely heavy payloads if you try to launch crew first.

Then, after you get the hang of sattelite launchers, I reccomend you use the Soyuz capsule from Tantares. Sure, it fits 2 people, not three, but it is amazing for LEO and MEO usage. I currently use them a lot, and plan to land one on the moon some day (created lunar concepts, never launched them).

[XpertKerbalKSP]

8 hours ago, Matuchkin said:

Umm, yeah. On that topic- don't start with kerbals. Use light satellites (comsats, weather satellites, mapping satellites, etc) NASA runs on those, and you will probably end up with extremely heavy payloads if you try to launch crew first.

Then, after you get the hang of sattelite launchers, I reccomend you use the Soyuz capsule from Tantares. Sure, it fits 2 people, not three, but it is amazing for LEO and MEO usage. I currently use them a lot, and plan to land one on the moon some day (created lunar concepts, never launched them).

The only time I've ever been successful in achieving orbit was on a manned flight. My second stage ran out of fuel so I had to use my command-service module to circularize. It wasn't really realistic...

But the thing is, I didn't install FAR and Dealdy Re-entry so the re-entry heat was stcok, and you know what happens if you re-enter the atmosphere in the stock game at 7,000 m/s. I had to push the ignore max. temperature button. Then, I deployed the chutes, which I apparently configured incorrectly and my sip crashed into the pacific at 430 m/s. Yeah.

Could you please tell me how to configure parachute with Real Chute?

Thanks, again!

[Blue_Eagle7]

1 hour ago, XpertKerbalKSP said:

The only time I've ever been successful in achieving orbit was on a manned flight. My second stage ran out of fuel so I had to use my command-service module to circularize. It wasn't really realistic...

But the thing is, I didn't install FAR and Dealdy Re-entry so the re-entry heat was stcok, and you know what happens if you re-enter the atmosphere in the stock game at 7,000 m/s. I had to push the ignore max. temperature button. Then, I deployed the chutes, which I apparently configured incorrectly and my sip crashed into the pacific at 430 m/s. Yeah.

Could you please tell me how to configure parachute with Real Chute?

Thanks, again!

To configure chutes go in the action group tab in the VAB and there you can change parameters for every chute (there are a lot of options but you have just to set some of them like Height Deployment and it will set the chutes accordingly).

Going unmanned can be helpful because you can go over high g on launch and you can also go lighter (but control that avionics support the mass of the rocket). And of course with unmanned you don't have to return the ship so no kerbal harmed )

(Aren't FAR and Deadly Re-entry necessary for RO?)

[XpertKerbalKSP]

35 minutes ago, Blue_Eagle7 said:

To configure chutes go in the action group tab in the VAB and there you can change parameters for every chute (there are a lot of options but you have just to set some of them like Height Deployment and it will set the chutes accordingly).

Going unmanned can be helpful because you can go over high g on launch and you can also go lighter (but control that avionics support the mass of the rocket). And of course with unmanned you don't have to return the ship so no kerbal harmed )

(Aren't FAR and Deadly Re-entry necessary for RO?)

Yes, but what numbers should I put in each of the parameters?

[Blue_Eagle7]

They should be already ok, just set the number of chutes and check the Height Deployment (i lower it to 20km to don't burn them but i don't know if its the best option)

[Matuchkin]

5 hours ago, XpertKerbalKSP said:

Yes, but what numbers should I put in each of the parameters?

I don't put in any numbers at first. For safety, I try to see when my ship will stop flaming like hell and fly nice-and-peaceful, then I right-click on the chute and instantly pre-deploy it (by dragging the first slider all the way up). I then wait to get to a good altitude, then deploy the chute fully by sliding the second slider all the way. The reason for that is that the parachute altitude is measured from sea level, so there isn't any way of knowing if you're gonna crash into the terrain itself before chute deployment.