Thinking about making the switch to FAR.

[capi3101]

Greetings, all.

For the better part of a year now, I've been flying spaceplanes. It's taken me a while to learn the necessary tricks and to gather the tools I needed to be able to fly an aircraft into space consistently, but I've gotten to the point where I can do it consistently and have designs with specific purposes - such as lifting a full orange tank to orbit, delivering a Mun lander to orbit and bringing it back down to the runway, and delivering a space station crew to their post - around Mun. Now, from the beginning I've been flying with the game's stock aerodynamic model, which everyone (including the developers) thinks is pretty heavily flawed and which is scheduled to be heavily overhauled with the coming KSP version 1.0. Given that the replacement system will handle closer to the way FAR handles things, I've been considering making the switch from stock to FAR for the past couple of weeks. To that end, I built a challenge where I asked folks to lift the same Mun lander I did to LKO and bring it back down again using FAR (or NEAR), with the idea of learning a thing or two from the entrants. No one has entered, so at this point I thought I'd take a slightly more direct approach.

Basically, I'm looking for information on how to design a craft and fly it to orbit using FAR - that goes for both spaceplane and rockets. What I'm really looking for is an answer to this question - is it worth making the switch?

For my specific questions:

-SPACEPLANE DESIGN-

When I design a spaceplane, I first and foremost use the principles listed in Keptin's Basic Aircraft Design Explained - Simply with Pictures guide. I'm assuming those principles will be all the more important with the FAR aerodynamic model. I also have been adhering to DocMoriarty's KSP Space Plane Construction and Operation Guide for general figures on how to build craft (especially Chapter 2.4, "Numbers You Should Know Before Construction"). Those figures go like this:

-A maximum takeoff mass of 10 tonnes for Basic Jet Engines (and these for aircraft and VTOLs only), 13 tonnes for RAPIERs and 15 tonnes for Turbojets.

-Approximately 2.3 tonnes of mass per delta wing; I myself use the easier-to-remember 1:1 ratio of mass-to-summed lift coefficient.

-1.5kN of SAS per tonne of takeoff mass.

-39 units of Liquid Fuel per tonne of maximum take-off mass (I use 40), and 23-24 tonnes for Oxidizer per tonne of take-off mass (I use 25).

He has other guidelines for number of rudders, number of ailerons and number of elevators/canards, which I do follow but don't really feel like discussing here.

Do these same guidlines still apply in FAR? The big one for me (and the one that may kill any notion of a switchover) is that I've heard Turbojets are seriously nerfed in FAR itself. I have no intention of installing an aircraft parts mod (such as B9) at this time - I have a slow box and a fair number of mods as it is - and the Turbojet is what I generally use to get to space these days. How badly has it been nerfed? What is its maximum takeoff mass in FAR? Has the RAPIER been similarly nerfed?

-SPACEPLANE FLIGHT-

Okay, my typical launch profile for a plane in the soup goes like this:

* Above 45 degrees through the first ten kilometers of atmosphere

* 40 degrees from 10-15k

* 30 degrees from 15-20k

* 20 degrees from 20-30k

* 10 degrees from 30k through switchover.

And that's in general. I try to keep the rate of ascent about 100 m/s or as close to that as I can manage through the ascent, and will adjust my nose angle as needed. I'm assuming in FAR that this is not how I want to do things, that I'm going to want to keep the AoA closer to 23 degrees throughout the flight. Does that sound right?

I'm assuming that landing on the runway will still be the same; deorbit so that your periapsis is 44k over KSC and take it on in the rest of the way once you're subsonic. I've heard that in FAR, you need to do a series of turns to bleed off speed. I'm curious if there's a way to set up an "airbrake" in FAR as well. Also, what exactly is the function of flaps and spoilers?

-ROCKET DESIGN-

Here's where I think I may get into the most trouble. I usually design my boosters asparagus, and I know that FAR doesn't like short rockets with the CoM too far up the rocket (stock is that way too, but I imagine the effect is more pronounced). Anyway, I use Temstar's guidelines to build asparagus:

- Assume a 15% payload fraction to calculate the mass of the rocket.

- Assume a 1.65 launch TWR to calculate the amount of thrust needed for the theoretical rocket mass.

- Assume 22% of that thrust will need to be in the core, and divvy the rest of it out to the boosters (I almost always use 6 boosters, which works out to 13% of the thrust per booster engine)

- Select the rocket engines necessary to produce the required amount of thrust, adjusting the thrust limiters as needed.

- Subtract the payload and engine mass from the theoretical rocket mass, and an additional two tonnes for "incidentals" (seperatrons, decouplers, a probe core for the core and battery power, etc.)

- Divide the remaining mass by 7 to get the full fuel tank mass per stack, and find a tank or set of tanks that puts me in the ballpark.

- Build the booster based on the figures calculated and make further adjustments to the thrust limiters.

That typically gets me a 4,500 m/s booster with a launch TWR of 1.65. In FAR, I imagine I'll have to go back to serial staging, which I can do but which gets to be such a bite. I know that I only need 3,500 in FAR; is 1.65 still a good launch TWR? Are there any other worlds where there's a difference in launch TWR?

-ROCKET FLIGHT-

A typical launch for me goes like this:

-Straight up to 10k

-Nose over to 45 degrees and hold until 35 seconds to apoapsis.

-Nose to 20 degrees and hold until 45 seconds to apoapsis.

-Nose to 10 degrees and hold until 55 seconds to apoapsis.

-Fly along (or even below) the horizon until MECO.

Now, I've heard that the nose over needs to be gradual, that a sudden swing to 45 degrees will result in a tumbling rocket. Where would you all recommend the turn commence, and how gradual does it need to be?

That's pretty much all I'm going to ask about for now. One final question - are there any good tutorials out there for those who, like me, are taking the plunge, and need to unlearn a few things? Thank you all in advance for your replies.

Edited February 24, 2015 by capi3101
flipping the switch

[EdFred]

I installed FAR this weekend. I don't do spaceplanes, and for me it was a "meh" experience. I built a very simple rocket, and learned that MechJeb and FAR do not get along at all. I was better off manually flying the rocket than I was letting MJ do the ascent, and I messed with the settings like crazy. I will say it takes A LOT less DV to make orbit if you design streamlined rockets. And MJ's landing prediction is nowhere even close to accurate with FAR installed. Oh, I only missed my landing target by 70km? But after watching my rockets have less than a 5degree angle of attack and tumbling out of control, I uninstalled it.

[LethalDose]

Learning FAR is learning to fly again. You've giving a lot of details that, IMO, is putting way more effort into figuring it out than you need.

It takes about 4500 m/s to get into orbit under stock, and 3500 m/s to get into orbit with FAR. Just get KER to get these dV values. However you want to build a rocket that can get your payload into LKO with those dV totals will work.

Start turning over just a few degrees right off the pad. Broader rockets will just add drag. Not sure you're locking all those parameters instead of just launching what you need.

ALso, you don't need a 1.65 TWR in FAR, only need about 1.1-1.3.

Addendum: Forgot your question near the top of the post: Is it worth making the switch? Yes. Stock aero is Krap.

Edited February 23, 2015 by LethalDose

[Van Disaster]

Turbojets:

*Heavily* nerfed. The basic jet won't get you supersonic, the other one is probably about half it's power and runs out at around 1300m/s. There are strong reasons for this though, given how the rest of FAR works. Rapiers are still suitable engines for spaceplanes.

The rest of the guidelines, forget it. For sanity's sake you want a minimum jet TWR of about 0.3 but that's pretty flexible - if you have a really slick low-drag design you can go lower. There's no real guidelines about control surfaces because that's also dependent on your design - fortunately FAR gives you a couple of tools you can check your craft with, you don't even have to understand them too well, just enough to either know "red is bad" for the static tab, or what shapes are bad for the graphs. Wing area - well, divide the total area by the craft mass and you'll get the wing loading, higher means higher takeoff/landing speed but compensates by being lower drag ( relatively ) because you have less wing for the overall size of the craft. Countering that, you'll need to fly higher AoA angles which will increase drag again. So you can see there's no simple rules.

Generally if I was to try and analyse how I think I've got enough wing - I look at the top of the plane, imagine it has straight wings who's span is about that of the fuselage, imagine their chord length is about 1/4-1/3 span and then start morphing that area into a suitable wing shape depending on the craft. Really though I just look at something and go "yes, now that has enough wing I think" and then check what AoA it will fly at for a few target speeds.

My flightplan for a heavy spaceplane goes "preset 12deg pitch hold on the runway" using Pilot assistant SSAS, and fly that to space obvously if it needs it I'll adjust so I don't fly too fast or slowly at different altitudes - too fast down low and there's possible damage and it's a waste of fuel, too slow up high and Lift/Drag goes a bit too far towards drag. Deorbiting I start about half an orbit back, put peri about 15km over the landing site, and generally just stay flat, making sure I don't go over 40k Q ( dynamic pressure ). You don't need to bleed speed doing aerobatics if your descent profile is nice and gentle.

Spoilers are just aerodynamic braking devices. Flaps also slow you down, but they also provide more lift at lower speeds - they're giving part of the wing a higher angle of attack. If you put them off-centre of CoL then they'll work like elevator surfaces & pitch the plane around, so you'd better have some good compensating elevators.

Rockets: 1.2ish TWR, start turning at 80m/s or so - if you've got a good rocket you can turn all stability & guidance off and just give it a nudge at that point, and it'll go all the way to orbit by itself - just keep turning. Ballpark of 45-50deg over at 10km and pretty much all the way over at 28km. dV for very low Kerbin orbit 3000-3800.

Is it worth switching? well I've been using FAR since about a month after I started playing, back at possibly 0.18.3 ( I had the demo before then but I don't remember when I got the full game - but that's some idea of timespan ) when I got frustrated that the stock aero just didn't make any sense, and never regretted it once aside from when it had the odd bug itself . Nobody can say how close the new stock aero will be to FAR, but I suspect a lot nearer to FAR than the current one, so hey give it a go. Don't bother with NEAR though, it was created as a joke

Edited February 23, 2015 by Van Disaster

[Rokmonkey]

I use FAR Exclusively, though I only fly rockets. I can't even get space planes to work right in stock.

I definitely suggest you switch to FAR, don't do NEAR, especially if you are going to fly spaceplanes. You NEED Mach effects to slow you down. NEAR doesn't include those so you slip right through the atmosphere at incredible speed.

Now, as far as rockets go, I tend to build slim realistic rockets. At most I have one set of liquid fueled boosters that pump directly to the main stack, but usually not even that. You don't need much dV, and unless you are launching 1000tons into orbit, you don't need big rockets, even in stock.

So, some tips and tricks with rockets:

-Total dV requirements for launch are in the range of 3300 - 3800m/s depending on your launch profile. I recommend you build a couple standard launchers and use those to get your payloads to orbit, that way you can learn the ascent curves easier.

-Get a mod with Fairings. I like KW because it's a fun design constraint, packing things into small fairings but Procedural works just as well. Also, use nose cones!

-Always check your COM and Center of Pressure (or Center of Lift in KSP terms, it isn't actually a thing in reality). If your COP is above your COM, you need to be a little cautious with your gravity turn, go to far and you will go unstable. This is where people get turned off with FAR. A gentle turn will ease you right into orbit. Or you can do what I do, slap a couple lifting surfaces at the base of your center stack. You just need it to get you through the lower atmosphere. 30,000 meters up, it's not so much of a big deal. They don't even need to be control surfaces, I use wing strakes usually.

-As was said earlier, keep your TWR low on launch, I usually shoot for something around 1.2

As far as space planes are concerned, use the tweakables on the control surfaces. You don't usually want so much control authority, so turn off yaw and roll on your wing control surfaces near your fuselage, enable only roll on the ones out at the tips. Keep yaw on the vertical stabilizer, but turn off everything else. You may also want to turn down the ctrl deflection.

Flaps-When enabled, usually for take off, they drastically increase drag and lift. This allows you to get off the runway easier.

Spoilers-When enabled, they reduce lift and increase drag helping you land.

As a rule with FAR, simple efficient designs are your best bet. Massive asparagused rockets are a no go, far to much waste.

[Red Iron Crown]

If you haven't gone FAR yet, I would not bother at this point. Wait and see how the new stock model turns out first, then decide which way to go.

[eddiew]

You're never wrong to install FAR. I've had it since my 2nd week of KSP If it gives you grief, just pop the options and turn off structural failures for an easier (arguably more fun) ride where stuff still flies sensibly but doesn't collapse when you sneeze.

As for jets - don't worry about them being nerfed. It's still viable to make a turbojet/rocket spaceplane, because of the atmospheric density changes.

Spaceplane ascent is more velocity based than AoA based. I go for:

- mach 1 by 10km

- mach 2.2 by 20km

- mach 3.5 by 25km, holding until mach 5 (where your turbojets will max out)

- rise to 30km, or as near as you can get, trying not to bleed speed, throttling as necessary to stay within your air intake allowance

- when finally forced onto rockets, pull up and get past 50km as quickly as possible

- point prograde; there's not much drag up here, so just nudge your AP along ahead of you and let your PE rise

Oh, and the big one; take time to understand FAR's stability calculations window. It'll tell you before launch if you won't be able to fly. Check the three points I've listed above are all green, and if so you'll most probably go to space today

[WhiteKnuckle]

You've got a lot of questions so I'll try to just answer some of the basic ones...

is it worth making the switch?

YES! If you like to fly things you should get FAR. If your idea of fun is just telling MJ to get you to orbit, then no, FAR won't really do anything for you.

Do these same guidlines still apply in FAR? The big one for me (and the one that may kill any notion of a switchover) is that I've heard Turbojets are seriously nerfed in FAR itself. I have no intention of installing an aircraft parts mod (such as B9) at this time - I have a slow box and a fair number of mods as it is - and the Turbojet is what I generally use to get to space these days. How badly has it been nerfed? What is its maximum takeoff mass in FAR? Has the RAPIER been similarly nerfed?

There really aren't any formulas for FAR, it's all about trade offs. More wing will get you off the ground at a lower speed, but cause a lot of drag at high speeds. It's about finding a balance that works for whatever you're building.

Turbojets are Nerfed, but only in the sense that they don't make a lot of thrust at low speeds and altitudes, and they won't push you to orbital velocities on their own. B9 actually nerfs jets even more (although it does give you some nice dual mode engines to make up for it).

I don't know what you mean by "maximum takeoff mass"? With enough thrust and surface area you can get just about anything off the ground.

I'm assuming that landing on the runway will still be the same; deorbit so that your periapsis is 44k over KSC and take it on in the rest of the way once you're subsonic. I've heard that in FAR, you need to do a series of turns to bleed off speed. I'm curious if there's a way to set up an "airbrake" in FAR as well. Also, what exactly is the function of flaps and spoilers?

I burn retrograde about 1/4 to 1/3 of an orbit ahead of KSC until my path hits the ground near KSC. The air is a lot thinner with FAR so dropping your Pe to 44k will mean overshooting KSC by about half an orbit.

Newer versions of FAR include a skin-drag model that will slow you down pretty quick at low altitudes, so I almost never do turns to bleed off speed. Instead I use altitude to control speed. Came in to early? Just level off at 20k and you can glide for quite a ways. Comming in too hot? Just drop down to 5k and you'll shed speed pretty quick.

Flaps cause the wing they're mounted on to produce more lift/drag, usefull for getting big heavy things off the runway. I almost never use them.

Spoilers turn control surfaces into air-brakes (they can still function as control surfaces) You can set max deflection speratly for the control surface and spoiler functions. They're great for slowing down once you've landed.

I'll come back to this a little latter to answer some more questions, but simply put: If you want things to work a little more like they do in the real world, and you like to spend time designing things you can be proud of: Get FAR.

[Alshain]

Turbojets:

*Heavily* nerfed. The basic jet won't get you supersonic, the other one is probably about half it's power and runs out at around 1300m/s. There are strong reasons for this though, given how the rest of FAR works. Rapiers are still suitable engines for spaceplanes.

You make it sound like turbojets aren't suitable for spaceplanes. Only the basic jet is not good for spaceplanes, Turbo Jets work just fine. They are nerfed but if you are ascending properly, that is ok. The nerf is there because FAR's aerodynamic reduces drag based on design and they become too powerful as a result (your plane gets ripped to shreds). The only downside to TurboJets is you need separate rockets, but in many cases you can build nothing more than an OMS out of O-10's to get you that final distance, unless it's just a really big plane or you are planning on going somewhere other than orbit. RAPIERS are nerfed in FAR too so TurboJets still get you more power, they just don't get as fast.

The biggest problems I see are when people don't carefully assign their air intake (something that will be fixed in 1.0). The Intake Build Aid mod can help with that. A plane with 2 turbojets and 4 intakes with all the intakes on only 1 engine won't get you higher than about 25km-30km before needing to switch to rockets. Properly assigned intakes on a adequately sized plane for the TurboJets should get you pretty close to sub-orbital and then all you need is that OMS to get the periapsis up. If you're doing that, RAPIERS won't help either.

I've recently started building an entire line of orbital carriers without any LFO engines and I'm wondering now why I didn't do that the day the O-10's were released. For now, until the rebalance in 1.0, it seems to be the way to go.

[Van Disaster]

If the rapier wasn't a thing I'd still be using turbojet/nuclear combos - I spent a long time using those even when B9 Sabres appeared and occasionally still build one for the hell of it. I've found generally that just swapping a turbojet for a rapier seems reasonable ( and well, I use big B9 sabres for big craft now anyway ). FAR turbojets are not going to get you that near orbital velocity on Kerbin though ( they can on Laythe if you're patient! ).

If you have a high wing loading - if you're building large you tend to end up with a pretty high wing loading anyway given current parts don't favour blended wing/lifting body designs - you're not going to get much out of intake spamming - you won't have the speed to get enough lift out of the wing to get any higher without going faster. Using SABRES I'll switch at 25-30km, at that point I can't go any faster, and I've got to the point that pitching up more isn't actually gaining anything.

[tater]

I switched to far after playing maybe a month. I never noticed any difference whatsoever. I've never even tried MJ, though.

[Alshain]

If the rapier wasn't a thing I'd still be using turbojet/nuclear combos - I spent a long time using those even when B9 Sabres appeared and occasionally still build one for the hell of it. I've found generally that just swapping a turbojet for a rapier seems reasonable ( and well, I use big B9 sabres for big craft now anyway ). FAR turbojets are not going to get you that near orbital velocity on Kerbin though ( they can on Laythe if you're patient! ).

They don't have to get you to orbital, they have to get you suborbital. I can get a reasonable suborbital trajectory with just TurboJets, after which I switch to monoprop to bring up the periapsis. The LFO is so much heavier too, when you drop down to just enough LF to power the jets (which isn't much) and Monoprop for the O-10's your plane ends up very low mass.

If you have a high wing loading - if you're building large you tend to end up with a pretty high wing loading anyway given current parts don't favour blended wing/lifting body designs - you're not going to get much out of intake spamming - you won't have the speed to get enough lift out of the wing to get any higher without going faster. Using SABRES I'll switch at 25-30km, at that point I can't go any faster, and I've got to the point that pitching up more isn't actually gaining anything.

2 intakes per engine is hardly intake spamming. You can probably do it with just a single shock cone per Turbojet. I can easily get to 300km orbit using this design. My smallest plane has 2 turbojets, 4 structural intakes, and 0-10's only and it gets there just fine in FAR. But, I don't switch to to the monoprop until about 45km.

[Van Disaster]

What size plane are we talking? mk1 size or mk3? going ballistic extra-atmosphere with stock turbojets with a Mk3-size craft would seem to want enough turbojets that you might as well use a rocket...

Did a quick& dirty conversion of a medium B9 plane with turbojets & nukes, obviously not enough turbojets:

They run out of puff rather fast, that's ~half takeoff thrust. Would behoove Squad to make a bigger Rapier for 1.0, I think.

Edit: actually they're ~50kN at takeoff which seems a bit low even after FAR's got at them. Think I'll investigate what's going on there...

I should point out that it's not the plugin that nerfs engines, it's a modulemanager patch included in the FAR distro. You could just not use that & have your stock rated engines still.

Edited February 23, 2015 by Van Disaster

[Rokmonkey]

I switched to far after playing maybe a month. I never noticed any difference whatsoever. I've never even tried MJ, though.

Uhh, you should have. It drastically changes the atmosphere. You should have at least noticed that you need less fuel to get to orbit. If you are running Windows 64-bit, FAR turns itself off so that would mean you didn't notice it. If you aren't, then I have no idea.

[capi3101]

Thank you all for your replies so far. I probably should've mentioned that I do use Intake Build Aid and KER; Mechjeb has long been my scheduled reward for a successful launch from Eve, something I've yet to accomplish...

Anyways,

I don't know what you mean by "maximum takeoff mass"? With enough thrust and surface area you can get just about anything off the ground.

I meant that folks flying the souposphere have determined that there is a point past which the efficiency of the craft - and your chances of making it to space - drops off rapidly based on the number of engines you're working with. For Turbojets in the soup, that's about 15 tonnes per engine. That figure has been one of the keystones of my spaceplane design process for quite some time now.

I suppose I left out that whole part of my usual design process for spaceplanes - I usually start a design with the mass of the payload, with payload being "anything that doesn't help the craft get into orbit". The obvious example is a space probe that you're launching to orbit. I usually start with the mass of that payload and assume a 25% payload fraction, which in the soup is generally what you get with a truly sucky-suck-suck design. So let's say I have a six tonne probe I want to launch. I multiply that by four - 24 tonnes. 15 tonnes max payload per Turbojet, so I know A) I need to build a two engine craft and I can assume the maximum mass - 30 tonnes in this case - when it comes to figuring out how much fuel I want on the craft and how many wing parts to put on. I also generally use three Ram intakes per engine (the guideline being 0.035 intake area per engine - left that one out). I generally design full "integrated engine units" by starting with an Engine Nacelle set along the craft's centerline. A Turbojet goes on the business end along with two-to-four 24-77s. I then take the Nacelle/engine assembly off, put it on the side of the craft, stick a tri-coupler on the other end of the Nacelle and then attach three Ram Intakes to the tricoupler. I'm assuming that the big fluting edge of the tricoupler is a huge no-no in FAR...

Is there a similar general design process for FAR?

Another big concern I have - right now in the soup I can load up an over-sized payload and get it into orbit. Take my Vampire Bat 7 design:

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Now - that flying pile of junk ain't making it to orbit in FAR; that's obvious. But let's say I wanted to do the same thing in FAR - a lander of the same design to orbit via spaceplane. I already know the lander is too big for any of the existing stock cargo bays; I tried fitting it into a Mk3 bay early in the design for no dice. How would I go about lifting that lander to orbit with FAR if I wanted to use a plane to do it? Is that even possible?

[Alshain]

What size plane are we talking? mk1 size or mk3? going ballistic extra-atmosphere with stock turbojets with a Mk3-size craft would seem to want enough turbojets that you might as well use a rocket...

Did a quick& dirty conversion of a medium B9 plane with turbojets & nukes, obviously not enough turbojets:

Well that explains it, B9 nerfs turbojets on top of FAR's nerfs. Delete that crap mod and they will work a lot better. Right now I'm working with Mk2 and they are just fine. I haven't tried Mk3, I suspect that might be pushing it a little.

[Van Disaster]

I think most people design payloads to fit their existing craft in FAR - optimising FAR spaceplanes ( as opposed to throwing one together that just happens to work ) is a reasonably involved and quite time-consuming process. If I have something that won't fit in a plane then I'll put it in a fairing & stick it to the top of a rocket.

- - - Updated - - -

Well that explains it, B9 nerfs turbojets on top of FAR's nerfs. Delete that crap mod and they will work a lot better. Right now I'm working with Mk2 and they are just fine. I haven't tried Mk3, I suspect that might be pushing it a little.

Yeah... no. For starters the MM patches aren't multiplicative, one replaces the other ( aside from B9's basic jet, which actually increases the thrust +4% ) so no they don't nerf on top of each other - the only thing that may mix up is the velocity curve, and B9's is *less* of a nerf than FAR's. Having dumped my DB out it's using the less restrictive version, so yes that's as good as it gets.

"B9: crap mod"? not even going to bother.

[WhiteKnuckle]

Is there a similar general design process for FAR?

I don't think so (could be very wrong though).

The reason you can use a formula like that in stock is because weight is the only important metric. In FAR you have to worry about drag due to the type of parts you use and how you place them. The waters get very muddy very quick. This shouldn't turn you off to using FAR, it just means you'll need to test and tweak your designs a bit as you go. You can't just build something to a formula and be sure it'll get to space. After a while you just get a feel for it. At this point I could build you a light cargo (say 10 ton) spaceplane from scratch in 10 minutes.

Now - that flying pile of junk ain't making it to orbit in FAR; that's obvious. But let's say I wanted to do the same thing in FAR - a lander of the same design to orbit via spaceplane. I already know the lander is too big for any of the existing stock cargo bays; I tried fitting it into a Mk3 bay early in the design for no dice. How would I go about lifting that lander to orbit with FAR if I wanted to use a plane to do it? Is that even possible?

External load cargo in FAR is tricky. To be honest I may be one of the few people to have tried it.

I built this beast to tow an interplanetary ship to orbit:

Obviously my payload is pretty aerodynamic, and is designed to do an unpowered landing on it's own. But I could make a more traditional style lander that would work, it just couldn't be too unaerodynamic. The other thing you'd need is KAS to be able to re-strut the thing before re-entry. Docking ports alone will not keep a ship together.

- - - Updated - - -

Yeah... no. For starters the MM patches aren't multiplicative, one replaces the other ( aside from B9's basic jet, which actually increases the thrust +4% ) so no they don't nerf on top of each other - the only thing that may mix up is the velocity curve, and B9's is *less* of a nerf than FAR's. Having dumped my DB out it's using the less restrictive version, so yes that's as good as it gets.

"B9: crap mod"? not even going to bother.

B9 limits jets to mach 3.2 making them pretty useless for spaceplanes. B9 is great if you're using their SABER engines, but not so great if you're trying to get most of the way up on turbojets.

[Pecan]

is it worth making the switch?

I'm more or less in the same situation and think it is NOT worth the switch, simply because you'll have to re-learn things in FAR and then almost certainly do it all again for the new stock aerodynamics. I'm just going to wait and learn the new model.

- - - Updated - - -

...MechJeb and FAR do not get along at all. I was better off manually flying the rocket than I was letting MJ do the ascent, and I messed with the settings like crazy ... MJ's landing prediction is nowhere even close to accurate with FAR...

Did you tell MJ you'd changed all the rules by installing the MJ FAR-compatibility mod as well, or just blame it when its calculations based on stock conditions weren't accurate?

[Renegrade]

If you haven't gone FAR yet, I would not bother at this point. Wait and see how the new stock model turns out first, then decide which way to go.

I'd actually say that the stock model is going to end up looking a lot like FAR. The various tidbits they've let drop have basically been a featurelist for FAR (supersonic effects, v^2 lift, cargo bay/fairing shielding, aero failures, etc). I'm sure there will be differences, but even if Squad does things very differently, FAR will still be closer to new stock aero than old stock aero. You can't do things like v^2 lift and proper Cd without it being NEAR or FAR like.

The only thing that stock seems to be missing is that intimidating stats panel.. (which isn't so bad once you get to know it, it really just needs clearer documentation) They have a .. stability assistance system of some kind though, but it sounds graphical instead.

So I'd say: Go FAR now, and then re-evaluate when new stock aero comes out.

[tater]

Uhh, you should have. It drastically changes the atmosphere. You should have at least noticed that you need less fuel to get to orbit. If you are running Windows 64-bit, FAR turns itself off so that would mean you didn't notice it. If you aren't, then I have no idea.

I also run KIDS. I'm not really interested in having a mod fly for me.

[Axelord FTW]

I'm more or less in the same situation and think it is NOT worth the switch, simply because you'll have to re-learn things in FAR and then almost certainly do it all again for the new stock aerodynamics. I'm just going to wait and learn the new model.

If the new stock aero is not on FAR's level, then I will also snob the new stock aero in favor of FAR (which will get brought to speed, I'm sure, if the new stock aero is not up to par). What would be the point of a new aerodynamic system if it wasn't even close to being more sensible than the current system?

[cicatrix]

My FAR history:

1. Installed

2. Frustrated

3. Removed

4. Frustrated

5. Installed again

6. Learned to fly

It's probably a good idea to get the feeling about how the stock aero would change. I don't know how the stock would be implemented, but anyway, from what I heard it's probably going to be far closer to FAR than the current stock.

Actually, I find it's easier to fly both planes and rockets with FAR. That's the main reason I installed it again (see #5).

Edited February 24, 2015 by cicatrix

[NathanKell]

I have to agree with Renegade here (sorry Red): IMO, based on what Squad has said, FAR is closer to what 1.0's aero will be like than 0.90soup is. In my estimation, it will probably be a mix of FAR, NEAR, and stock; I find it vanishingly unlikely that aspect ratio or sweep will make it in (although that would be awesome) so the lift you get for swept wings "spaceplane" wings will be higher than NEAR or FAR gives you, but you *will* get Mach Effects (those have been confirmed)--and reentry heat is a Mach Effect.

Anyway, on the to meat of the topic.

capi3101, you are in luck, because as Keptin's post says, Keptin wrote that post for FAR as well, and about half the stuff talked about in that post only applies to FAR, not stock: streamlining, aspect ratio, sweep, dihedral/anhedral, etc. Basically, you have to read that post with new eyes, and no longer discard all the information that's not relevant to stock KSP, no longer have to say to yourself "yeah, I know that's how it works in real life, but this is KSP"--with FAR, aerodynamics will behave much more like real life, and all those special factors Keptin talks about and then dismisses are modeled in FAR.

In FAR, drag and mass are 100% uncoupled: as long as you are producing more thrust than you are experiencing drag, you will accelerate. TWR does not matter for top speed at all. The only way mass matters is that the heavier you are the more lift you need, and thus the higher angle of attack (angle above the velocity vector) you will have to fly at to generate that lift (and the higher your AoA the more lift you get, but also more drag). However, that's only relevant for the same aircraft empty or full, not between different aircraft; a heavier aircraft with the same engine may well be much faster if it suffers less drag.

For that reason, and because wing shape as well as amount matters, there are no general rules regarding how much engine or how much wing to add-especially because you might need less wing area if it's long and narrow and unswept (high AR, low sweep = lotsa lift but low top speed) whereas a delta-winged spaceplane might need more wing area and get less lift out of it!

[cantab]

One tip I have for FAR: start by making conventional planes, with separate wings and tailplane. You can certainly make a spaceplane that way. Tailless delta aircraft, ie looking like Concorde, are much more difficult to make fly well.