Realism Overhaul Discussion Thread

[Maxsimal]

On 24.05.2016 at 0:53 PM, Combatsmithen said:

The margins are very very tight though. and the rocket is pretty expensive, 20k per launch, and takes a year to build with a VAB at .95 build speed

My moon mission rocket is 3.5k and has plenty of delta-v for post encounter manuevers.  There's definitely something you need to improve there.  Here's a few things you could check/do

1. Check your tank type.  Make sure you're not using the pressurized tank for your LR-87.  If you are, it's a big delta-V difference. Also make sure you push utilization to 100%.  AJ-10 will still need a pressurized tank.

2. Adjust your decoupler/fairing base sizes. You have a really big upper fairing there that probably is overlarge, causing drag, and you have a bunch of decouplers that are bigger than they need to be.  That's some significant mass savings.

3. Upper stage SRB is probably a big mistake.  And you're likely going on too high a trajectory, flatten it out,

4.  You should think about a 4-ish stage rocket design at your tech level(of course, it'll be many more stages in UI).  

• Your LR-81's as your liftoff engine.  SRB's are probably not needed unless your TWR with 3 LR-81's is really too low. 3-4k DV here   Liftoff TWR 1.2-1.7.  Drop two of the LR-81's & their tanks mid-boost for more efficieny
• Something in between with good vac ISP but also good thrust, like an LR 105, for the booster that gets you most of the way to LEO,  5-6k DV here.  Initial TWR ~1.
• Another good, but lower thrust engine finish circularizing and do a trans-lunar burn (Like the RD-105), ~4k DV here.  TWR doesn't matter, but will also likely be around 1 
• AJ-10(Mid, at least) or just some 1kn hydrazine thrusters) for course correction and lunar orbit insertion.  Depends on your mission, but around 2k Dv here.  Again, TWR doesn't matter so much, but <.5g will be efficient.

5. Save whatever weight you can on your lunar probe.  

Let me know if you need more help.

[Combatsmithen]

2 hours ago, Maxsimal said:

My moon mission rocket is 3.5k and has plenty of delta-v for post encounter manuevers.  There's definitely something you need to improve there.  Here's a few things you could check/do

1. Check your tank type.  Make sure you're not using the pressurized tank for your LR-87.  If you are, it's a big delta-V difference. Also make sure you push utilization to 100%.  AJ-10 will still need a pressurized tank.

2. Adjust your decoupler/fairing base sizes. You have a really big upper fairing there that probably is overlarge, causing drag, and you have a bunch of decouplers that are bigger than they need to be.  That's some significant mass savings.

3. Upper stage SRB is probably a big mistake.  And you're likely going on too high a trajectory, flatten it out,

4.  You should think about a 4-ish stage rocket design at your tech level(of course, it'll be many more stages in UI).  

• Your LR-81's as your liftoff engine.  SRB's are probably not needed unless your TWR with 3 LR-81's is really too low. 3-4k DV here   Liftoff TWR 1.2-1.7.  Drop two of the LR-81's & their tanks mid-boost for more efficieny
• Something in between with good vac ISP but also good thrust, like an LR 105, for the booster that gets you most of the way to LEO,  5-6k DV here.  Initial TWR ~1.
• Another good, but lower thrust engine finish circularizing and do a trans-lunar burn (Like the RD-105), ~4k DV here.  TWR doesn't matter, but will also likely be around 1 
• AJ-10(Mid, at least) or just some 1kn hydrazine thrusters) for course correction and lunar orbit insertion.  Depends on your mission, but around 2k Dv here.  Again, TWR doesn't matter so much, but <.5g will be efficient.

5. Save whatever weight you can on your lunar probe.  

Let me know if you need more help.

 

Thanks for the advice. I have learned ALOT since I last posted this and I have zero problems getting to orbit now, but I've been focusing on more orbital missions lately and have successfully placed 2 kerbals in orbit so far. I'm going to launch a third one later today to complete a contract that is to stay in space for 1 day and 3 hours. I just got new engine technology and i'm researching some better solar panels, and I also begun research on mature orbital rocketry.

[Combatsmithen]

Ok I have a problem. I have a polar orbit satellite that requires an apoapsis less than 704,849 meters, a periapsis more than 702,130 meters, and an inclination of EXACTLY 90 degrees. The problem is every time I adjust my inclination to EXACTLY 90 degrees, it lowers my orbit. Which in turn to raise the orbit I have to rotate the satellite using my RCS, but then by the RCS thrusting is messes up the inclination again. So there is literally no way to complete the contact. And its worth a lot and expires in about a 1 year time. Its not even like they give you a margin of error. It has to be 90 degrees and THATS IT. Not 89.999 or 90.001. EXACTLY 90 which is why its IMPOSSIBLE. I have a picture of the contract and the vessel. But Imgur doesn't want to work.

Edited May 26, 2016 by Combatsmithen

[Padishar]

1 hour ago, Combatsmithen said:

Ok I have a problem. I have a polar orbit satellite that requires an apoapsis less than 704,849 meters, a periapsis more than 702,130 meters, and an inclination of EXACTLY 90 degrees. The problem is every time I adjust my inclination to EXACTLY 90 degrees, it lowers my orbit. Which in turn to raise the orbit I have to rotate the satellite using my RCS, but then by the RCS thrusting is messes up the inclination again. So there is literally no way to complete the contact. And its worth a lot and expires in about a 1 year time. Its not even like they give you a margin of error. It has to be 90 degrees and THATS IT. Not 89.999 or 90.001. EXACTLY 90 which is why its IMPOSSIBLE. I have a picture of the contract. But Imgur doesn't want to work.

Perhaps, rather than rotating the vessel to alter the inclination, you could leave the vessel pointed prograde/retrograde and use translation RCS to perform the adjustment burns?  This should allow you to set the inclination accurately and then adjust the altitude (again, using translation RCS) without needing to rotate in between.

Also, assuming you are running 1.1.2, then bear in mind there is currently an issue with decaying orbits, so I would get the inclination as close to correct as possible first, then set the Ap to ~704,800m and then set Pe to as close to the Ap as possible.  Then, you can nudge the orbit sideways using RCS as you pass over the equator if necessary...

Edited May 26, 2016 by Padishar

[Combatsmithen]

1 hour ago, Padishar said:

Perhaps, rather than rotating the vessel to alter the inclination, you could leave the vessel pointed prograde/retrograde and use translation RCS to perform the adjustment burns?  This should allow you to set the inclination accurately and then adjust the altitude (again, using translation RCS) without needing to rotate in between.

Also, assuming you are running 1.1.2, then bear in mind there is currently an issue with decaying orbits, so I would get the inclination as close to correct as possible first, then set the Ap to ~704,800m and then set Pe to as close to the Ap as possible.  Then, you can nudge the orbit sideways using RCS as you pass over the equator if necessary...

 

I haven't had issues with decaying orbits. But sadly I don't have 5 way RCS unlocked yet. Or reaction wheels. I was thinking that if I had reaction wheels I could rotate the craft with them and just use RCS for the translational controls

[rsparkyc]

51 minutes ago, Combatsmithen said:

I haven't had issues with decaying orbits. But sadly I don't have 5 way RCS unlocked yet. Or reaction wheels. I was thinking that if I had reaction wheels I could rotate the craft with them and just use RCS for the translational controls

If you put a set of 4 nozzles on both the top and bottom of your craft (helpful to center around the COM), then you don't need any other RCS engines to be unlocked.

[Combatsmithen]

1 hour ago, rsparkyc said:

If you put a set of 4 nozzles on both the top and bottom of your craft (helpful to center around the COM), then you don't need any other RCS engines to be unlocked.

The linear nozzles?

 

[rsparkyc]

Just now, Combatsmithen said:

The linear nozzles?

 

yep.  I do something similar here to orient my craft: https://youtu.be/ILBm-9GKBeM?t=6m48s. You could add another set on top to provide translation.  This setup, however, does nothing to stop rotation.

 

[Combatsmithen]

1 hour ago, rsparkyc said:

yep.  I do something similar here to orient my craft: https://youtu.be/ILBm-9GKBeM?t=6m48s. You could add another set on top to provide translation.  This setup, however, does nothing to stop rotation.

 

 

 

Ok ill try that then. I have 4 way RCS for rotation in a tri-symmetry setup. Im also going to start making a realism overhaul series on my channel! Im going to sub to you sub back if you like

Edited May 26, 2016 by Combatsmithen

[rsparkyc]

47 minutes ago, Combatsmithen said:

Ok ill try that then. I have 4 way RCS for rotation in a tri-symmetry setup. Im also going to start making a realism overhaul series on my channel! Im going to sub to you sub back if you like

For sure! I'd love to see what other people are building!

[rafty4]

Hi!

I'm having issues with docking, in that I'm hitting the port itself (dead center), but just bouncing off - there appears to be no docking magnetism, and no matter how much pushing I do I can't get a capture. I've even been into the RO files and adjusted the capture range from 0.05m to 1.05m, and still no luck.

I'm using the small propellant-only docking port.

Anybody else had a similar issue? Am I missing something obvious?

Edited May 27, 2016 by rafty4

[Motokid600]

is there a way to increase the ignitions on an engine with additional tanks of TEA-TEB?

[TrooperCooper]

10 hours ago, rafty4 said:

Hi!

I'm having issues with docking, in that I'm hitting the port itself (dead center), but just bouncing off - there appears to be no docking magnetism, and no matter how much pushing I do I can't get a capture. I've even been into the RO files and adjusted the capture range from 0.05m to 1.05m, and still no luck.

I'm using the small propellant-only docking port.

Anybody else had a similar issue? Am I missing something obvious?

 

Not sure what the problem is, but I can say that I have been using the propelant-only docking port just fine in my RP-0 career about a week ago or so. No problem with the Apollo docking ports either...

 

[rafty4]

 

9 hours ago, TrooperCooper said:

 

Not sure what the problem is, but I can say that I have been using the propelant-only docking port just fine in my RP-0 career about a week ago or so. No problem with the Apollo docking ports either...

 

My suspicion is it's somehow as a result of porting the game from 1.0.4 to 1.1, although I have others - are you using Ven's stock revamp?

Also, is there now a correct drill with which party has their docking bumper extended?

Many thanks!

Edited May 28, 2016 by rafty4

[TrooperCooper]

14 hours ago, rafty4 said:

 

My suspicion is it's somehow as a result of porting the game from 1.0.4 to 1.1, although I have others - are you using Ven's stock revamp?

Also, is there now a correct drill with which party has their docking bumper extended?

Many thanks!

 

Yes, Ven's is part of the RP-0 setup. Not sure about drill/docking/bumbper...

 

[stratochief66]

I had similar problems with docking, although I only ever tried with the FASA Apollo / LEM. I asked NathanKell to attempt to reproduce my issue (of not being able to get them to dock) but I'm not sure if he got around to it?

It could very well be caused by us changing all/most docking ports to be 'gendered' where they should be, and insufficient testing to confirmm that worked alright afterwards.

 

@NathanKell ?

[Streetwind]

Hi all, I'm looking for a spot of help.

After getting some reports about Near Future engines breaking when installed together with Realism Overhaul, I'm looking to update the extremely outdated compatibility patch shipped by RO (to be found here). As it turns out, there is already an issue raised about NF stuff in general on the RO Github as well (to be found here).

As you can read in that issue thread, I'm not an experienced RO player, and I don't want to make a pull request that doesn't end up matching the quality standards for the mod (to avoid wasting both of our times). So I'll need some help understanding how things are intended to be laid out, and such things. I've alreay posted some questions in the issue thread, but it seems like it's not attracting enough attention. So I'm posting here in hopes of it being picked up by someone who can assist.

Thanks for reading!

[mileshatem]

Quick question regarding RO with TestFlight: should my engines "Rated burn time" and "Current reliability" increase as I collect more and more data? I've got nearly 7700/10000 data on my AJ 10, but the reliability isn't increasing (still at 460s MTBF, 1m55s rated burn time).

[leudaimon]

AFAIK rated burn time is fixed, but MTBF increases as you accumulate data. You can find more detailed information in the TestFlight wiki: https://github.com/KSP-RO/TestFlight/wiki/Quick-Start

[mileshatem]

I see, so it seems like the engines are rated to a burn time, and as you collect more and more data, you're more likely to get to that rated burn time? And once you have lots of data, you might even exceed it a bit, but typically not by much since it seems like the momentary failure rate begins climbing rather rapidly as you approach and exceed the rated burn time. 

I guess I was hoping that as you got more data for the engines, the average useful burn time would increase as well, mainly because the early game engines all seem to be rated to 1-2mins, which isn't all that useful for anything but sounding rockets. I suppose I need to research better engines.

Anyways, thanks for the help.

[Phineas Freak]

@mileshatemacquiring more data units allows the engines to be pushed a bit "harder" but always under the "burn - through" time limitation, while making sure that the engine will operate correctly (i.e. no loss of thrust, explosions, shutdowns) for it's rated burn time.

Burn time is "hard - coded" parameter for all rocket engines (not talking about KSP but for the real life). A design meant to last for 2 minutes cannot be expected to operate without problems for 3 or 4 minutes. You either improve the engine or use a different one.

Edited June 4, 2016 by Phineas Freak

[mileshatem]

I see your point, but I'd argue that extending burn times past their rated time is a bit more doable in real life than with TestFlight. For ablative cooled designs there would be a hard cutoff time, but it'd probably be a good bit after the "rated" burn time due to design margin. Though I suppose the TestFlight rated time could be simulating the zero-margin time for the engines instead. For regeneratively cooled designs, once they reach steady-state operation there's a lot less stress on the system and they should be able to fire a good bit longer than the standard duty cycle, which is why you can test fire the engine for a full duty cycle, then later use it again for another full cycle during launch.

But either way, now that I understand the mechanic of the mod, I can work with it. I just was expecting the rated times to increase and thought I was having an issue because they wern't. Thanks for the help everyone.

[Space Cat]

10 hours ago, Phineas Freak said:

@mileshatemengines (not talking about KSP but for the real life). A design meant to last for 2 minutes cannot be expected to operate without problems for 3 or 4 minutes. You either improve the engine or use a different one.

At that point, you are introducing so many variables into engine choice that you don't have a real choice due to lack of options. Test Flight would be an awesome mod if paired with some sort of procedural engine mod that allows you to compromise between all of the relevant variables, maybe introducing engineering time and cost for new engine families and variants.

[gunt3rgam3r]

Hello everyone...thank you so much for this mod.  Just started a rp0 career with 1.2.1 and have been really enjoying it.  I have a few questions about how the mod works with parts.  There are several parts listed as non-rp0, which were installed with the ckan install...I am sure that the intent is to make those parts rp0 eventually.  My question is what is exactly involved in converting a part to rp0?  My guess that is that it involves converting the mass and other parameters to be appropriate is RSS in the .cfg files.  

Could someone point me to a place where this process is detailed?  

Thx again for the great mod, and all the work that everyone has put into it :-)

 

[leudaimon]

Welcome @gunt3rgam3r!

The first thing to know is that making a part compatible with RP-0 is a two step process. 

1) make the part RO compatible. This involves correcting mass, efficiency etc. to make it similar to real life. Parts that didn't go through this are labeled non-ro

2) make the part RP-0 compatible. This involves putting it in a tech node and giving it a price.Parts that didn't go through this are labeled non-RP-0 

I'm on mobile, so it's not easy to provide links, but the OPs for RO and RP-0 and their github repositories give more details.

 

Edited June 7, 2016 by leudaimon