[1.3.1] Ferram Aerospace Research: v0.15.9.1 "Liepmann" 4/2/18

[Yemo]

Yes i know that it's better than stock, but how can people in this thread make orbit with 2.9km/s of dV?

For an inline rocket it's possible that the difference is 800 m/s?

I doubt that this is possible without air breathers (which screw up the dV numbers)...

Edited March 23, 2015 by Yemo

[Daze]

I doubt that this is possible without air breathers (which screw up the dV numbers)...

So air-breathers?... Well after 3 years of KSP i'm still a noob

[Akira_R]

So air-breathers?... Well after 3 years of KSP i'm still a noob

Using Jet engines as boosters for your rocket. Since they are far more efficient in the lower atmo you can get to orbit using very small rockets. A standard chemical rocket launch is going to take around 3.5-3.9 Km/s of Dv to get to orbit.

Edited March 23, 2015 by Akira_R

[undercoveryankee]

Yes i know that it's better than stock, but how can people in this thread make orbit with 2.9km/s of dV?

For an inline rocket it's possible that the difference is 800 m/s?

For an idea of what factors into your delta-v performance, check out these numerical simulations at http://www.reddit.com/r/KerbalSpaceProgram/comments/2spalr/far_deltav_charts/ and http://www.reddit.com/r/KerbalSpaceProgram/comments/2u8b08/far_kerbin_and_earth_deltav_graphs_rev_2/ .

2.9 with pure rockets is right on the edge of possible if you get the pitch profile right and vary your TWR higher at the beginning and end and lower through max-Q. My personal record with constant full throttle is about 3.1.

The optimum flight path for delta-v usage isn't quite a pure gravity turn according to Ferram4. You make your gravity turn a little late to put you on a high arc that gets out of the thick air quicker, then gradually pitch a few degrees below prograde as decreasing drag permits. kOS is your friend here.

Edited March 23, 2015 by undercoveryankee

[Superfluous J]

Note that "pure dV" is not the best way to optimize a rocket. I personally optimize to cost. If two rockets get you into orbit would you rather have the one that does it for 800 less dV, or 100,000 less kerbucks?

[Daze]

For an idea of what factors into your delta-v performance, check out these numerical simulations at http://www.reddit.com/r/KerbalSpaceProgram/comments/2spalr/far_deltav_charts/ and http://www.reddit.com/r/KerbalSpaceProgram/comments/2u8b08/far_kerbin_and_earth_deltav_graphs_rev_2/ .

2.9 with pure rockets is right on the edge of possible if you get the pitch profile right and vary your TWR higher at the beginning and end and lower through max-Q. My personal record with constant full throttle is about 3.1.

The optimum flight path for delta-v usage isn't quite a pure gravity turn according to Ferram4. You make your gravity turn a little late to put you on a high arc that gets out of the thick air quicker, then gradually pitch a few degrees below prograde as decreasing drag permits. kOS is your friend here.

Very useful graphics! Thanks

Anyway by that graphic my rocket should need ~3.3 km/s but instead it needs 3.7, what can the problem? Drag? Gravity turn (i made it very smoothly and similar to the one of the graphic so i don't think it's the problem)?

@5th: stopped playing career, so i don't have that problem

[Superfluous J]

@5th: stopped playing career, so i don't have that problem

Oh so you're just optimizing for the fun of optimizing. By all means then, continue

However, you can still optimize to cost even though you don't care about it. It's not any different from optimizing to total dV even though you don't care about it. The costs are at least listed in the (stock) game, unlike dV

[Van Disaster]

I've managed 3.1k without jets, but I had fairly large fins - large enough to be wings - a pretty flat profile. It's probably best to fiddle with your trajectory first, my winged rocket had something that looked more like a midrange ICBM - initially fairly steep full burn, flatten out significantly once I had some speed up & was out of the thickest atmosphere, cruise up making the best use of the wings with slightly reduced thrust and then back to full burn when the wings were getting less effective.

[Hodo]

I don't think that ferram really cares about what will come on the new version regarding his mod other than the fact that it will be disableable.

Stock KSP cannot be as complete as this mod, that is too much for the stock game, IMO, and the next FAR update will change how things work very drastically.

@Hodo: Are you using the release or development version? Don't use the development version unless you are really testing it.

I am using release version, I tested the development version and it caused some issues wasnt able to nail it down at that time.

[Pecan]

Jets will not reduce your dV requirement one bit; they'll just provide the required dV more fuel-efficiently.

To get the best from them you'll need to spend more time in atmosphere though, which implies a higher (but still more fuel-efficient) dV budget.

[NathanKell]

1. The heavier your LV, the lower your drag losses will be (cube-square law).

2. The faster your initial kick, the lower your gravity losses will be. For this reason high-thrust solids that burn out fast become a reasonable option, despite the low Isp.

[Auranapse]

I noticed when installing this that the engine no longer runs at full thrust even when I throttled 100%. But while still at the same altitude and I stall the plane and point it to something other than the prograde vector(and the plane drifts in the air sideways) the engine thrust increases, is this an intended effect? I find it weird since the air intakes will take in lesser air and the thrust should decrease.

[cantab]

Jet engine thrust changes with speed, and FAR tweaks it to be more pronounced than in stock. Are you slowing down when doing your manoeuvre?

[Auranapse]

Yep, it definitely slows down XD. Then there should be no issues I guess.

Might want to read more on how jet engines behave in RL.

[tetryds]

Yep, it definitely slows down XD. Then there should be no issues I guess.

Might want to read more on how jet engines behave in RL.

You can also use AJE, current stock engines are a bit weird.

BTW, without AJE, FAR cuts the thrust of every (inc mods) airbreathing engine by half, only the basic jet remains untouched because it's thrust drops a lot with speed.

[BlueTiger12]

Perhaps anybody of you have an Idea to my problem?

Just posting again, because i think it got lost. ;-)

Hello Ferram

I really love this mod.

But since a few installs (even clean installs; i think since version 24.2) i have a problem in the sph.

Whenever i right click on a control surface or a wing, the game is getting stuck for ~2 seconds. After this it is really really slow (about 3 fps)

Even tweaking in the right click menu is going that slow.

As soon as you click anywhere and the menu closes this problem is gone

Problem stopped with uninstalling far.

Do you know about this allready?

Otherwise i would take a deep look if it is a problem with some mods i have installed

[Hodo]

Doesn't sound like a FAR problem Blue, it sounds like you have a conflict somewhere with FAR. Do you have an output.log you can post?

Because really Ferram can't do diddly squat without it.

[BlueTiger12]

Hmmm

it seems to be some kind of incompatibility with another mod i think

i also think my output log wouldn't help, it is i think a little bit spammed because i am also doing some bug related testing for kct at the moment.

but if this is a unknown problem, i will take a deeper look into it;-)

it seems to be a persistend problem, because i have it over several versions and several fresh installs

[blowfish]

If you can't provide an output log and reproduction steps, no one, least of all ferram4, is going to be able to help you. If want support, you need to isolate the bug.

[BlueTiger12]

That is my point blowfish

I just wanted to know if this problem is allready known and looked after.

Because if there was allready a sollution for that problem, it would be useless to waste several hours in isolating the bug again.

That is why i asked if that problem is allready known...

[taniwha]

BlueTiger12: anf for those of us who know how to read logs, a log file is the fastest way to determine if what you have is a new bug or a different manifestation of a known bug.

[Guest Darth Gerbil]

When launching planes from the vab, the airbrakes both turn in the same direction instead of towards each other. This only happens when launching vehicles from the VAB.

[futrtrubl]

When launching planes from the vab, the airbrakes both turn in the same direction instead of towards each other. This only happens when launching vehicles from the VAB.

Brakes turn up. So if you use it on vertical control surfaces expect weirdness.

[ferram4]

Alright, version 0.14.7 is out. It reduces intake drag somewhat, handles high-vertex geometry faster (only noticeable when loading parts/vessels), adjusts very high AoA wing drag to be at higher, more realistic levels (this should make stalling somewhat more bearable) and includes tetryds's Colibri as an example VTOL craft. Also fixes a rather nasty bug that could prevent custom FARBasicDragModels from being loaded up, thanks to NathanKell's bugfixing.

[Climberfx]

Is possible to this update solve the FAR config behaviors on Cap. Kypard Skylon?