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

[smjjames]

Ferram makes things fly as long as you hide in a little weak 32 bit hole.

Attitude much?

Besides, 1.0 is having a massive stock aerodynamics change and Squad is no longer supporting the 64x version of KSP.

[taniwha]

Attitude much?

Besides, 1.0 is having a massive stock aerodynamics change and Squad is no longer supporting the 64x version of KSP.

Not quite true: 64-bit KSP on Linux is very much supported still, which makes Creeperchair's attitude stink all the more.

[tetryds]

Please guys, don't start this discussion once again.

[smjjames]

@taniwha: I wasn't sure about Linux, but yeah, they did drop all support for windows 64bit

Please guys, don't start this discussion once again.

On what? I was just rebuttling creeperchairs attitude.

[Lenny551]

I don't know if it is supposed to be impossible to launch a rocket or if it is just me not being able to fly, whenever I launch a rocket it go up for a few meter and than starts to turn extremely white sas on and I'm not able to correct it.

[Dazpoet]

I don't know if it is supposed to be impossible to launch a rocket or if it is just me not being able to fly, whenever I launch a rocket it go up for a few meter and than starts to turn extremely white sas on and I'm not able to correct it.

Is your rocket by any chance assymetrical? A picture would help.

[tetryds]

I don't know if it is supposed to be impossible to launch a rocket or if it is just me not being able to fly, whenever I launch a rocket it go up for a few meter and than starts to turn extremely white sas on and I'm not able to correct it.

Add winglets to the bottom of your rocket, and nosecones to the top.

[Azruim]

Why is FAR limiting thrust on basic jet engine? Allthough if my plane fully stalls I get full thrust. So far I haven't had problems with any other engines. Maybe I'm missing a setting somewhere?

[taniwha]

Azruim: stock jet engine thrust is for stock soup.

[tetryds]

Why is FAR limiting thrust on basic jet engine? Allthough if my plane fully stalls I get full thrust. So far I haven't had problems with any other engines. Maybe I'm missing a setting somewhere?

FAR does not limit thrust on the basic jet engine, but the basic jet engine's thrust drops considerably as you move faster.

With FAR it's a lot easier to go faster so you end up noticing that speed effect more.

Edit: though, the turbojet has its thrust cut by half.

Edited March 9, 2015 by tetryds

[BudgetHedgehog]

Why is FAR limiting thrust on basic jet engine? Allthough if my plane fully stalls I get full thrust. So far I haven't had problems with any other engines. Maybe I'm missing a setting somewhere?

Because they have unreasonably high thrust in order to push through the stock soup. Halving the thrust is sensible and makes them not so OP.

[Azruim]

Azruim: stock jet engine thrust is for stock soup.

FAR does not limit thrust on the basic jet engine, but the basic jet engine's thrust drops considerably as you move faster.

With FAR it's a lot easier to go faster so you end up noticing that speed effect more.

Edit: though, the turbojet has its thrust cut by half.

Because they have unreasonably high thrust in order to push through the stock soup. Halving the thrust is sensible and makes them not so OP.

Thanks! I actually noticed the speed differences too comparing to stock ksp just now. BTW which thread would be suitable to discuss Deadly Re-entry mod settings for FAR?

[Lenny551]

Dazpoet: Is your rocket by any chance assymetrical? A picture would help.

As far as I know it's symetrical:

tetryds : Add winglets to the bottom of your rocket, and nosecones to the top.

I have them only I don't know if the once in the middel are helping or making it worse.

[Svm420]

Totally anecdotal, but I find at time wings mid way up can shift CoL above a CoM of most bottom heavy rockets. Leading to flipping. Have you checked your CoM CoL in the van. I know that amount to asking if you have your computer plugged in, but thought I'd still say something.

[blowfish]

When do you loose control? It looks like your rocket would become unstable after solid booster separation because those have the fins.

[Superfluous J]

When do you loose control? It looks like your rocket would become unstable after solid booster separation because those have the fins.

Yeah I'd drop the top fins entirely. It also looks like - unless you severely tweaked those solids down, that thing takes off like a... well like a rocket By the time you ditch the solids you may be going WAY too fast to keep it going straight. Try starting with somewhere between 1.2 and 1.6 TWR at launch and just let that slowly ramp itself up naturally until the solids burn out.

[Van Disaster]

So, how does FAR determine if a part is a nosecone? presumably it's a bit more than only having one node. I've been trying to debug a drag issue with Retrofuture parts:

Initially thought the adapter was the problem, because... well, that's a stupid amount of drag.

However stacking two in a row pushed the problem to just the front one. Next I stuck a cubic strut inbetween the nosecone & the adapter:

so now the adapter's drag level is fine, but...

that strut definitely isn't. So, it has to be an issue with that nosecone - there's only one node configured in it, and dumping the MM db out showed only one node still, so I'm not too sure where to go with it.

[tetryds]

So, how does FAR determine if a part is a nosecone? presumably it's a bit more than only having one node. I've been trying to debug a drag issue with Retrofuture parts:

Initially thought the adapter was the problem, because... well, that's a stupid amount of drag.

https://farm8.staticflickr.com/7600/16745254886_f19c40c1ab_c.jpg

However stacking two in a row pushed the problem to just the front one. Next I stuck a cubic strut inbetween the nosecone & the adapter:

https://farm8.staticflickr.com/7641/16771128195_c117756070_c.jpg

so now the adapter's drag level is fine, but...

https://farm8.staticflickr.com/7597/16771130835_28866678cf_c.jpg

that strut definitely isn't. So, it has to be an issue with that nosecone - there's only one node configured in it, and dumping the MM db out showed only one node still, so I'm not too sure where to go with it.

Stage a radial decoupler and it will fix that bug.

[Van Disaster]

While that does sanitise the issue, is this something that can be fixed permanently with a custom FAR config for the part?

[blowfish]

While that does sanitise the issue, is this something that can be fixed permanently with a custom FAR config for the part?

I believe the issue is related to part clipping detection, so I don't think so.

[Khazar]

I have earned enough money so I could upgrade necessary facilities and turn toward space. I have even managed to put kerbal on the mun. (one of 2 kerbals survived landing and mission designed as a 2 way trip turned into one way trip, so lets call it half-success ).

I have some questions about rocket designs and flight.

Craft that allowed me to get to mun costed little over 100k, and after I got into mun's orbit I had 2 engines 4 fuel tanks (http://wiki.kerbalspaceprogram.com/wiki/FL-T400_Fuel_Tank but 2 of them were allready empty.

It was built like that :

Part that was designed to go to the mun, seen form top : Command pod mk 1, control wheel, science lab jr, command pod mk I (turned upside down), stack decoupler. There was also some scientific aparature attached, 4 landing struts, 4 chutes, 4 solar panels. Then there were 4 radial decouplers set as two pairs. Each decoupler had attached 2 fl-t400 fuel tanks and one engine. This was craft that supposed to land on mun's surface.

All this was put on top of rocket that had 2 stages, each stage had 9 engines ( http://wiki.kerbalspaceprogram.com/wiki/LV-T45_Liquid_Fuel_Engine ) each equipped with 2 fl-t400 fuel tanks.

I guess its not a very efficient way to build rocket but it haven't anything better so far.

So now for the questions :

1. Is it better to add more fuel tanks per engine or add more stages instead ? I usually use 2 fuel tanks per engine but have no idea if its reasonable.

2. As far as I know its a good idea to gently turn east after passing 10k alt, and keep turning until 45 degree. Then what ? I have read that when periapsis is above 70k i should cut the throttle and wait until I'm neat it, then turn horizontal and accelerate until apoasis is above 70 as well. Is it right ? Wouldnt it be better to keep turning as sharp as I can maintain stability ? Or instead cutting throttle after apoasis is 70k, wouldn't it be better to turn horizontal (or near it) and keep accelerating ? I usually have apoasis of 70k somewhere between 50-60k alt and I think its quite possible to go at 60-70 degree at this alt.

3. After I reach let's say 50k alt, and there is almost no air, and I have 4 engines (2 fuel tanks per engine) is it better to use all 4 at once or is it better to use 2 first and then drop them to reduce weight ? I guess the stronger is the gravity the more reasonable would be to use all engines but where would be the edge ?

4. Is there sometung like maximal alt for recon mission (if not specified in contract ? ). I easily managed to set my orbit around mun that way so I could fly over required sectors and was able to take crew reports and therefore complete the mission. Would that work with kerbin ? If I could go over 70k that would be easy, but if i had to get lower than that then I doubt it would be good way to do this missions

5. Also is it more efficient to get orbit of just above 70k or beter go higher ? Considering I'm aiming for the mun would it be better to get basic orbit of around 70k and then maneuver towards mun, or would be better to get basic orbit of lets say 100k or higher ?

Edited March 10, 2015 by Khazar

[futrtrubl]

1. Is it better to add more fuel tanks per engine or add more stages instead ? I usually use 2 fuel tanks per engine but have no idea if its reasonable.

2. As far as I know its a good idea to gently turn east after passing 10k alt, and keep turning until 45 degree. Then what ? I have read that when periapsis is above 70k i should cut the throttle and wait until I'm neat it, then turn horizontal and accelerate until apoasis is above 70 as well. Is it right ? Wouldnt it be better to keep turning as sharp as I can maintain stability ? Or instead cutting throttle after apoasis is 70k, wouldn't it be better to turn horizontal (or near it) and keep accelerating ? I usually have apoasis of 70k somewhere between 50-60k alt and I think its quite possible to go at 60-70 degree at this alt.

3. After I reach let's say 50k alt, and there is almost no air, and I have 4 engines (2 fuel tanks per engine) is it better to use all 4 at once or is it better to use 2 first and then drop them to reduce weight ? I guess the stronger is the gravity the more reasonable would be to use all engines but where would be the edge ?

4. Is there sometung like maximal alt for recon mission (if not specified in contract ? ). I easily managed to set my orbit around mun that way so I could fly over required sectors and was able to take crew reports and therefore complete the mission. Would that work with kerbin ? If I could go over 70k that would be easy, but if i had to get lower than that then I doubt it would be good way to do this missions

5. Also is it more efficient to get orbit of just above 70k or beter go higher ? Considering I'm aiming for the mun would it be better to get basic orbit of around 70k and then maneuver towards mun, or would be better to get basic orbit of lets say 100k or higher ?

1. That totally depends on too many factors. For an efficient launch vehicle you tend to want an equal amount of deltaV in each stage, except perhaps less deltaV in the first stage if you are using solids there. You also want to maintain a TWR (thrust to weight ratio) of around 2.

2. That is true for stock. For FAR you want to start your turn much earlier, anywhere from 1km of altitude down to right off the pad. You then keep your nose roughly on your surface velocity vector until you are pretty much horizontal. Aim to be horizontal anywhere from 35km to 60km in altitude. Once your apoapsis reaches your desired orbit then cut your engines until you reach apoapsis and burn prograde to circularize.

3. It is always more efficient to use all engines, otherwise they are dead weight. If you can use less engines then it means you overbuilt. As long as you can maintain enough TWR ( and beyond ascent and landing a TWR of 0.5 is more than sufficient for orbital maneuvers.) you have enough thrust.

4. I believe it works the same for Kerbin yes.

5. It's more efficient to burn low. Having said that a burn to the Mun or higher can take a while, and part of that time you may be burning a bit towards Kerbin and if you start very low like 70kmish then you might find yourself entering the atmosphere. Again this depends on your TWR. An extremely high TWR, above 3 - 4, and your burns are very short so you don't point too much at Kerbin at the start so you can start low. An extremely low TWR, like below 0.2, and you will need to start higher like nearer 100km.

Edward

[cantab]

So, I finally managed a Basic Jet spaceplane in FAR. https://flic.kr/p/rwAvu9

The whole thing is loosely based on the Avro Vulcan. I climb steadily to reach 19 km and Mach 0.9, then light the rocket engine and accelerate and climb to around 30 km, through the aeroplane-spacecraft transition, then carry on much as for a rocket. Re-entry has yet to be tested.

Still needs refinement of course. My biggest problem throughout has been getting enough pitch control authority. The built-in trim on the wing trailing edge helped but it still struggles.

And a question. What effect will overlapping elevons have in FAR? Not major control surface spam, just small overlaps to avoid leaving gaps.

[blowfish]

And a question. What effect will overlapping elevons have in FAR? Not major control surface spam, just small overlaps to avoid leaving gaps.

They should be treated as being more or less continuous.

[ferram4]

@Van Disaster: FAR does not provide special treatment for nosecones. They are treated exactly the same as any other part. Nevertheless, those issues are the result of nasty edge cases introduced by part clipping becoming a thing; the overhaul I'm working on should make that moot, but that will take some time.

@cantab: Overlapping the elevons slightly won't have any negative effects (in theory), but that's not gonna help much. The stock control surfaces are simply not designed for vehicles that large; you'll likely need to move to procedural wings to get the control surface area you need for controlling that thing.