Too fast landings

[tomf]

It might be a good idea to practice landing away from KSC Find a nice flat plain somewhere and practice flying low and slow. I find that having an actual point that I want to land at - the runway - makes it harder than if you just alow your glide to take you down to the ground and land wherever you happen to end up.

[DrMonte]

It might be a good idea to practice landing away from KSC Find a nice flat plain somewhere and practice flying low and slow. I find that having an actual point that I want to land at - the runway - makes it harder than if you just alow your glide to take you down to the ground and land wherever you happen to end up.

You can land near the Runway.

[MisterFister]

You only have one photo that shows your undercarriage. Is your problem that you tip forward and tumble on the runway at touchdown? If so, your undercarriage wheelbase is WAY too short. Send your nose gear farther forward to counteract this. Note that landing gear are physics-less parts. Yes, they show in the SPH as having mass, and that mass will manipulate the CoM indicator, but it's important to ignore this. (Finish all aerodynamic changes to the craft BEFORE adding the undercarriage.) When physics load on your vehicle, your landing gear (as well as other things like ladders, struts, fuel lines, and many other things) will be treated as not-there, massless, dragless, non-entity items. Their collision mesh will still exist, that's how landing gear keep you elevated form the runway before takeoff roll, of course. With your wheelbase so short, your plane on touchdown will have almost no rolling-on-ground pitch stability and I can imagine that it would result in faceplants.

Also, get used to flying at low speeds higher up. 260m/s is more than half the speed of sound at sea level, as indicated by other commenters here. FAR will have some useful readouts in the SPH to indicate flight and pitch stability across multiple performance envelopes. Try experimenting with those across a .1-.2 mach speed range.

To get a decent idea of your stall speed, try experimenting with it during your takeoff roll. Use quickloads to try to ascertain exactly what the minimum slowest takeoff rotation speed is. Feather your throttle, or even tweak-limit your max thrust for greater feathering precision. If you nosedive off the far end of the runway into the ocean at, say, 180m/s, then your stall speed is faster than that. If your stall speed is anything faster than 100m/s, then I would question your design's airworthiness in general. (And even then, stall speed of 100m/s would make landings hellacious-at-best. Doable, but would require lots of whiteknuckle.)

[The_Rocketeer]

Flaps are NOT brakes. They should only be deployed as you approach stall speed in order to increase lift. If you put the flaps down on a real aircraft at the kinds of speeds being suggested they'd jam, blow (over-extend), or simply tear off.

If I had to guess what the problem is I'd say your landing gear are too close together (it looks like you're tipping nose down based on your navball on boom). When you burn off that fuel your CoM will move forward or backward, and if it moves beyond where your gears are located then your plane will overbalance. Try spreading the gears out to nearer the wingtips and nose, or just tweak the tanks empty and see how the CoM lines up with your gears on dry(er) tanks.

Edit: ^^ What he said!

Edited October 22, 2014 by The_Rocketeer

[KBluey]

What happens when you slow down? Does the nose tip down? If so, your COM is probably too far ahead of your COL. Move your wings forward, install more SAS. If the plane is just falling out of the sky when you slow down, then it's too heavy for its wing area. Drop some weight or add some wings. And bear in mind that a plane that "looks right" for real life may not work well in the game because Kerbal physics is an intriguing approximation, it's not real physics....

[cadaverific]

If it helps at all i had the same question when i first started FAR seriously and made a post on it. Wanderfound and Hodo had some very nicely written explanations on how to setup flaps and spoilers. They also covered their uses in helping take off and, most importantly for you, bleeding off speed for landing (as well as not having a crazy AOA to maintain level flight)

[bartekkru99]

Please people learn to read - In the title it's clearly written "Too FAST landings", I was saying, that it's really hard to slow down, not unstable (It is in fact a bit unstable when doing barrel rolls but it has nothing to do with landings)

EDIT:

I've turmed it into answered - I just need to try harder to slow it down

Edited October 24, 2014 by bartekkru99

[Hodo]

Please people learn to read - In the title it's clearly written "Too FAST landings", I was saying, that it's really hard to slow down, not unstable (It is in fact a bit unstable when doing barrel rolls but it has nothing to do with landings)

EDIT:

I've turmed it into answered - I just need to try harder to slow it down

I understand....

On the note of slowing down, I have had issues with it also. Some of my more "sleak" designs just don't bleed off energy like I would like and thus seem to retain speed like they are greased lightning.

All I can say is airbrakes and drag chutes after landing, I keep forgetting about those, but they REALLY help with high landing speeds without dealing with the insta-lock brakes.

[LethalDose]

I had this exact same problem after I started flying with FAR: I simply couldn't slow down effectively to land, and started this thread. The advice I got there wasn't much better than what's been posted here.

The best way I've found to slow down is to shut off the engines, get as low in the atmosphere as I can (~ 500-1000m) and then pull up to bleed off the speed by changing direction (pitching upward) and countering gravity. Once you're down to a comfortable speed, fly downward toward the close end of the runway and when you reach it (~100m altitude), pull up again to kill speed, and maintain an upward pitch until you touch down.

I use VOID, so I'm able to watch my vertical speed while landing easily. If I'm going to fast, I increase my descent rate, and then pull up again, but not so much to gain altitude. Wash, rinse, repeat.

Don't need air-brakes, drag-chutes, flaps, blah blah blah. Just remember that every time you use your wings to change your flight direction, you're bleeding off kinetic energy, which is what you want.

[GoSlash27]

Please people learn to read - In the title it's clearly written "Too FAST landings", I was saying, that it's really hard to slow down, not unstable (It is in fact a bit unstable when doing barrel rolls but it has nothing to do with landings)

EDIT:

I've turmed it into answered - I just need to try harder to slow it down

"People please learn to read"? Wow, talk about biting the hand that feeds you...

If you want to slow down prior to landing, the best thing to do is fly an overhead "spin" pattern prior to landing.

Come overhead the runway at 300M and cut the throttle while banking left 45* to head west. Once on-speed (about 120 M/sec), drop the gear and fly west until the runway is about 45* behind you on the left.

Then bank 30* left for lineup to final approach and use the throttle to maintain your glideslope and pitch to maintain speed.

Consider that your last freebie from me. I know how to fly and you don't. I'm more than happy to help teach you... *if* you display the proper attitude, which you haven't so far. It's all the same to me if you continue leaving smoking craters.

Regards,

-Slashy

[merlinux]

I just had a quick look at this thread and I am a little baffled by the OP's question.

Wthout thrust and with positive pitch you will always loose speed. So why would you not just reduce thrust?

My best advice is to watch some flight school videos and/or learn how to fly a basic plane on a real sim, and i am sure you will have a lot more fun with ksp.

Btw in ksp I hardly use flaps and never speed brakes and I have no problem landing.

EDIT: Other advice, once you have settled your speed issue and know how much throttle you need depending on your flight profile (take off/climb/cruise/descent/landing), practise landing at a vertical speed -5 to -10m/s. Using ILS on a real sim will help you memorise how to land and soon you will not need the ILS anymore...

Edited October 25, 2014 by merlinux

[bartekkru99]

As I said it is already answered and I'm using FAR, so don't be surprised, that I can't slow down.

EDIT: I'm working on my hypersonic SSTO design.

[The_Rocketeer]

As I said it is already answered and I'm using FAR, so don't be surprised, that I can't slow down.

EDIT: I'm working on my hypersonic SSTO design.

Sounds like FAR isn't a very clever mod if it breaks aerodynamic drag.

Speaking from experience, the question that a person asks is often not the question they're should be asking to solve their problem. I apologise if I assumed your question falls into this group, but you didn't provide a particularly excellent description of the problem.

[LethalDose]

Sounds like FAR isn't a very clever mod if it breaks aerodynamic drag.

Speaking from experience, the question that a person asks is often not the question they're should be asking to solve their problem. I apologise if I assumed your question falls into this group, but you didn't provide a particularly excellent description of the problem.

FAR doesn't break aerodynamic drag, it tries to fix krap-awful model the devs have in the game currently. It changes the atmosphere and lift/drag model and atmospheric qualities to something that is far less horrible. It's just take some work to re-learn how to fly with it after playing with stock.

[The_Rocketeer]

Nonetheless, any aircraft with 0 thrust should experience a fairly rapid rate of deceleration unless it is also undergoing a proportionate rate of descent. That's just basic physics.

Needless to say, FAR isn't a mod I use. Stock atmo physics are simple to understand and do an adequate job for a game based mainly in space.

ANYWAY...

Back to topic?

[Hodo]

Nonetheless, any aircraft with 0 thrust should experience a fairly rapid rate of deceleration unless it is also undergoing a proportionate rate of descent. That's just basic physics.

Needless to say, FAR isn't a mod I use. Stock atmo physics are simple to understand and do an adequate job for a game based mainly in space.

ANYWAY...

Back to topic?

With FAR you will experience pretty rapid deceleration just nothing as great as the souposphere in the stock KSP. You have a realistic glide slope as in real life. Unlike the stock KSP where you can put wings on a brick and get it to fly faster then the speed of thought.

If you know nothing about how FAR works or even care to try it you should not talk about it.

[The_Rocketeer]

With FAR you will experience pretty rapid deceleration

Riiight. That's why this question got asked.

I can tell FAR has a few fanboys, so I'm not going to contribute to this any further. However, I am entitled to draw and publish my own conclusions about mods from sources other than firsthand experience. What you think about those conclusions are your business.

[Hodo]

Riiight. That's why this question got asked.

I can tell FAR has a few fanboys, so I'm not going to contribute to this any further. However, I am entitled to draw and publish my own conclusions about mods from sources other than firsthand experience. What you think about those conclusions are your business.

In FAR if you design an aircraft with no way of slowing down and is actually pretty clean as far as drag goes, it will maintain its energy level for quite a while, but if you design in drag systems, like air brakes it will help slow the craft down, just not like in stock KSP where you open an air brake and it will stop the craft in flight. Real aircraft don't work like that. Show me a high performance aircraft that with the engines off that will lose speed as fast as half of the designs in the stock KSP. The F-16 Fighting Falcon will glide for over a 70miles from 30kft! In FAR you can do the samething if you set up your glide slope right and it will bleed of energy at about the same rate.

Most people are not used to that when coming from the souposphere of stock. I did some tests last night for the 30min I did manage to play and got a high perfomance single engine fighter, that tops out at 23km at mach 3.8. And lands at 175kts, which is 90m/s.

So again, this question by the OP was in regaurds to FAR, not stock, so don't come in to a place where someone asked a question that had nothing to do with your style of play and bash his.

Edited October 25, 2014 by Hodo

[MisterFister]

I just had a quick look at this thread and I am a little baffled by the OP's question.

Wthout thrust and with positive pitch you will always loose speed. So why would you not just reduce thrust?

My best advice is to watch some flight school videos and/or learn how to fly a basic plane on a real sim, and i am sure you will have a lot more fun with ksp.

Btw in ksp I hardly use flaps and never speed brakes and I have no problem landing.

EDIT: Other advice, once you have settled your speed issue and know how much throttle you need depending on your flight profile (take off/climb/cruise/descent/landing), practise landing at a vertical speed -5 to -10m/s. Using ILS on a real sim will help you memorise how to land and soon you will not need the ILS anymore...

As I said it is already answered and I'm using FAR, so don't be surprised, that I can't slow down.

EDIT: I'm working on my hypersonic SSTO design.

I think it's perhaps overstating things a tad to say that the stock-preferring chap was "bashing" FAR-play. That said, it's likewise easy to overlook the fact that stock aerodynamics might as well be digital mayonnaise. I'm glad that the OP got the answer he was looking for. Simply, when you get used to playing in one physics regime (for this OP, that was apparently stock aerodynamics) and you make the switch to literally any other environment (again, in this case, FAR) there's going to be a learning curve that might at times not seem so obvious.

tldr; With FAR, you have to widen your approach lineups and start your final wayyyyy sooner than you'd otherwise have to in stock.

[eddiew]

Been struggling with the same challenge as the OP. I use NEAR (because I've only been playing KSP for 10 days and FAR looks really hard ) and have never flown in stock conditions, but landing can still be a pain. So far only achieved on the polar ice cap, where I just cut the engines and let it glide down super slow.

So I added radial mount parachutes to key points of the fuselage, and a few struts. Now I just have to get her below about 200 m/s and she'll hang together when the chutes deploy. Doesn't seem to hurt much either; twin turbojets and ram air scoops, ~1500 m/s top speed, maybe 20km ceiling, and gets 2/3 around the world on a full tank. Not gonna win any awards, but nicely for those flyover missions that Fine Print keeps giving me. And glows nicely in the dark

Would FAR be more brutal on the drag effect those chutes would have? (Alternatively, am I underestimating how much drag I'm getting from them?)

[bartekkru99]

FAR isn't that hard to understand. Now I'm makng my third fighter, I will try to make it supermaneuverable. It will be more Russian-like design, maybe something like PAK-FA or other sukhoi aircrafts, because I really like them.

[Hodo]

FAR isn't that hard to understand. Now I'm makng my third fighter, I will try to make it supermaneuverable. It will be more Russian-like design, maybe something like PAK-FA or other sukhoi aircrafts, because I really like them.

I was actually surprised at how well the Sukhoi and Mig designs actually work. Expecially the Mig-21 style delta and the Su-17.

I watched a documentary on the evolution of Soviet Fighters during the Cold War, they explained a lot of the design philosophy and thought process on some of the prototypes and produced fighters. I went as far as to test some of the designs myself in my RSS install of KSP with FAR. It is amazing how well these things translated over.

[bartekkru99]

I was actually surprised at how well the Sukhoi and Mig designs actually work. Expecially the Mig-21 style delta and the Su-17.

I watched a documentary on the evolution of Soviet Fighters during the Cold War, they explained a lot of the design philosophy and thought process on some of the prototypes and produced fighters. I went as far as to test some of the designs myself in my RSS install of KSP with FAR. It is amazing how well these things translated over.

By the way, is it possible to make super maneuverable aircraft, with only FAR installed - only stock parts? It would be cool to make Pugachev cobra in KSP

[Hodo]

By the way, is it possible to make super maneuverable aircraft, with only FAR installed - only stock parts? It would be cool to make Pugachev cobra in KSP

It is possible. The trick is placing the CoL as close as you can to the CoM, without the CoM moving to much and still having adequate control authority to do high AoA aspect turns. I made a delta wing design a while ago in my RSS install that could pull some pretty amazing G's in turns and really tight turn radius.

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[bartekkru99]

It is possible. The trick is placing the CoL as close as you can to the CoM, without the CoM moving to much and still having adequate control authority to do high AoA aspect turns. I made a delta wing design a while ago in my RSS install that could pull some pretty amazing G's in turns and really tight turn radius.

http://imgur.com/a/7k1ck

Stock no moded parts, just FAR. Now I'm trying to use canards, but when it reaches high AoA it starts to roll, it's really easy to recover, but makes it hard to fly.