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I've been playing KSP for a while now and just recently started getting into planes and space planes. I made a very basic plane out of stock parts and it flies great and everything but it almost seems too stable. I am on my 7th attempt of taking off and trying to land it the island runway. The problem is that no matter what I try I cant seem to lose speed. I come in from I would guess 25-30 KM out lined up with the runway at about 500-1000 meters up at a speed of around 100 m/s.

My engines are completely cut off and I have been trying to bank up to get wind resistance to increase drag to drop my velocity. Well that does work but I gain altitude. The instant I level out my artificial horizon my craft starts dropping somewhat but then my velocity increases basically right back to where I started making this never ending frustrating loop. It seems if I can fly forever with no thrust this way.

Is there something I'm missing in order to slow myself down? Any help would be appreciated. Thanks.

P.S. I do run some mods most notably FAR which may be affecting this. I do not have any parts packs that have air brakes although I am considering getting after this just because it is so frustrating.

Edited by KBMODIGITY
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With FAR you can set your wings to Flaps and Spoilers. Flaps increase lift at lower speeds, spoilers increase drag and slow you down. if you are having trouble loosing speed I would go with spoilers and come in slower and shallower for the island runway.

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This is natural, in the real world if something is dropped from orbit it will continue to pick up speed till it hits terminal velocity or the ground which ever happens first. So the answer is come in shallower perform some energy burning maneuvers like the space shuttle had to do on re-entry, and or add some air brakes to the craft from B9 or Firespitter and or set some control surfaces as spoilers. Flaps are not the right answer as they generate lift and drag, you want to generate drag more than lift at the point of wanting to slow down. And flaps may shear off at high speeds so also not a good choice.

As seen here, the thing sticking up in the center of the craft is an air brake from B9 mounted directly above the CoM as to not upset the crafts stability when in use.

LkQ2qs7.jpg

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While flaps and spoilers can help and sepatrons as brakes is.... kerbalish. Air brakes are a good option, however if a plane is going to fast the best solution is an S curve. Bank left, pull up, bank right, pull up. The act of turning a plane naturally slows it down due to the wind resistance of the bottom of the wings. Your flying in one direction and suddenly your plane is far less aerodynamic because it changed direction, thus slowing you down.

If you are going really fast don't do this, your plane will fall apart, go past the runway and circle around after you slow down instead. I for one have yet to land from a typical orbit going 90 degrees, I just can't seem to get over the mountain and down in speed an altitude fast enough, but if I circle around and come in at 270 degrees I find it much easier.

If your landing a heavy large craft, consider a drag chute from the real chutes mod. This will deploy once you are down and keep you from running off the opposite end of the runway.

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This is natural, in the real world if something is dropped from orbit it will continue to pick up speed till it hits terminal velocity or the ground which ever happens first. So the answer is come in shallower perform some energy burning maneuvers like the space shuttle had to do on re-entry, and or add some air brakes to the cr

It will pick up speed until drag from the atmosphere and force applied from gravity are in equlibrium, roughly depending on density, gravity force, shape and mass of the object.

To OP:

I'm new to this too. It took me some time to realize that with (i use NEAR since a few weeks) mods calculate drag very low compared to stock game. Had to use spoilers/air brakes from other mods or else was flying level, engines cut, along the whole runway without loosing much speed.

Another hint: when taking of remeber that speed, come in balanced and with a flat angle with no more than 20% more than that and you can touch down at the threshold under the weed. "Normally" you would use pitch to controll your speed and thrust to control sink/climb rate. In KSP, use spoilers or air brakes. Try it several times without touchdown, just go around. And leave space, come in on final approach from far away. The island runway is not easy to land ....

Hope that helped.

Edited by kemde
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As you may notice, pretty much everyone has their own preferred reentry and landing methods.

However, from your post it appears that you're just talking about landing, not reentry.

But it isn't really a problem. Just land at 100m/s; it's a perfectly fine landing speed. In fact, it's my standard landing velocity; I don't bother trying to get any slower than that. You shouldn't have any trouble coming to a stop on the runway without needing to resort to Sepratrons and the like.

You wouldn't land a Cessna at 100m/s, but a spaceplane ain't a Cessna. Even a small SSTO is big and heavy and fast, and even non-spacegoing KSP planes tend to be very heavy by aircraft standards. They usually have a relatively high stall speed, and if you drop below that, then yeah: it's going to plummet and start accelerating like a falling rock.

But they land just fine at 100m/s or even faster. Just make sure that you have the steering unlocked and brakes disabled on the front gear, be ready to do some very gentle steering and/or wing levelling on touchdown, and hit the brakes as soon as you've got it stably rolling down the strip.

Get lined up with the runway while it's still several kilometres away, kill your throttle completely, get down to within a couple of hundred metres off the deck and glide in to the strip. Gently adjust your pitch to keep your drop rate below about 5m/s or so. The lower and flatter the approach the better, so long as you don't clip the terrain on the way in. Trying to cut speed further with a last-minute flare is just going to create more problems than it solves.

Flaps can help lower your stall speed; spoilers can help in removing altitude without having to pitch down. But neither of these things are strictly necessary.

If you're not sure about your aircraft, have a play with this one: https://www.dropbox.com/s/5l3go4mgfrz2egj/Kerbodyne%20Evangelist%20II.craft?dl=0

It was designed as a trainer, and is very light, very agile and very stable. The ailerons are set as spoilers, linked to the brakes; they're good for holding you down once you're on the strip, or getting you down the last few metres if you find yourself floating just off the deck.

Edited by Wanderfound
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...

I somehow totally missed the part where he said 100m/s. I land at 150m/s, 100m/s is a perfectly fine landing speed for all the landing gear I know of. Just make sure the nose is up so you don't bounce, that's the important thing. Though you can still bounce and save it.

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Thanks for all the replies.

I think some of you misunderstood what I'm doing. Its a simple take off from the main runway, fly over to the island runway and land. My ship is only maybe 20 pieces, a very basic design. I never go above 2-3 KM in altitude. I think some of you are thinking I am trying to slow down from orbital speeds. That is planned down the road. Right now I am just trying to get used to basic flight design and principles. (yes I do have my center of lift barely behind my center of mass)

I think though that your ideas with the spoilers is what I'm looking for. I didn't know they had that in the game. I'll give it a try. Also thank you for the heads up on not enabling the front break.

My only last thought is that you all seem to agree that 100 m/s is a safe landing speed. To me that is insanely fast, going a kilometer in 10 seconds or basically 223 mph. I did do a few attempts where I said "ehh, just go for it" at that speed but all I did was bounce and flew away. Then again using a spoiler like you all said would hold me to the runway I'm hoping. I'll give my plane a quick readjustment and give it a try.

Thanks again for all the info.

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With FAR you can set your wings to Flaps and Spoilers. Flaps increase lift at lower speeds, spoilers increase drag and slow you down. if you are having trouble loosing speed I would go with spoilers and come in slower and shallower for the island runway.

Ok. I'm back in game at the hanger trying to set up these spoilers you guys recommend but I can't seem to figure out how to do it. I was able to disable the front end braking.

As far as parts all it is a cockpit with 2 MK1 fuselage attacked with 2 radial air intakes. 1 delta wing on each side with a standard control surface. And 1 delta deluxe winglet to act as my rudder. I do have some solar panels and a few science things on too and a battery. My thoughts were to use this as a Kerbin biome science grabber.

Anyways, if someone could tell me how to set up the spoiler it would be appreciated. Thanks.

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Thanks for all the replies.

I think some of you misunderstood what I'm doing. Its a simple take off from the main runway, fly over to the island runway and land. My ship is only maybe 20 pieces, a very basic design. I never go above 2-3 KM in altitude. I think some of you are thinking I am trying to slow down from orbital speeds. That is planned down the road. Right now I am just trying to get used to basic flight design and principles. (yes I do have my center of lift barely behind my center of mass)

I think though that your ideas with the spoilers is what I'm looking for. I didn't know they had that in the game. I'll give it a try. Also thank you for the heads up on not enabling the front break.

My only last thought is that you all seem to agree that 100 m/s is a safe landing speed. To me that is insanely fast, going a kilometer in 10 seconds or basically 223 mph. I did do a few attempts where I said "ehh, just go for it" at that speed but all I did was bounce and flew away. Then again using a spoiler like you all said would hold me to the runway I'm hoping. I'll give my plane a quick readjustment and give it a try.

Thanks again for all the info.

Do you have a picture of the craft?

You may not have enough wing surface to actually generate lift, or you have to much wing and you are generating far more lift then you need.

Either way flaps and spoilers.

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Ok. I'm back in game at the hanger trying to set up these spoilers you guys recommend but I can't seem to figure out how to do it. I was able to disable the front end braking.

As far as parts all it is a cockpit with 2 MK1 fuselage attacked with 2 radial air intakes. 1 delta wing on each side with a standard control surface. And 1 delta deluxe winglet to act as my rudder. I do have some solar panels and a few science things on too and a battery. My thoughts were to use this as a Kerbin biome science grabber.

Anyways, if someone could tell me how to set up the spoiler it would be appreciated. Thanks.

Ok, to set spoilers and flaps.

1. Right click the control surface you want to use. Choose Use as spoiler/flap.

2. Set and action group to control them, I use 1 for Increase Flap, 2 for Decrease, 3 for toggle spoilers, but you can use whatever you want.

3. By default brakes will activate spoilers but I recommend removing that. You don't always want spoilers and brakes at the same time. The spoiler can help you pitch the nose up but you wheels shouldn't be braked right as you touch down. Worse still if you use a custom group for spoilers and then turn on brakes, they turn back off when you want them. So remove them from brakes.

Finally, yes 100m/s is fine. Some of my SSTO's will not land at less than 150m/s because I can't keep the nose up any lower. However, that is a small runway. So you can either slow down more or use Real Chutes to stop before you plow into the hill at the other end (just like the Space Shuttle!) Just make sure you configure them, they are configured by switching to action group mode and clicking them. There you can set them to deploy on touchdown and to be drag chutes instead of main chutes for rocket pods. Also since your probably taking off from the KSC and landing on the island, make sure you set them to calculate from Wet Mass (i.e. a full tank of fuel).

Edited by Alshain
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My only last thought is that you all seem to agree that 100 m/s is a safe landing speed. To me that is insanely fast, going a kilometer in 10 seconds or basically 223 mph. I did do a few attempts where I said "ehh, just go for it" at that speed but all I did was bounce and flew away. Then again using a spoiler like you all said would hold me to the runway I'm hoping. I'll give my plane a quick readjustment and give it a try.

It's worth keeping in mind that the game was first designed to simulate rockets, then spaceplanes were added, then players started messing about with atmospheric aircraft on their own. The further you get from the original design, the more Kerbally the physics become. Due to the weight of parts etc., even a small and simple KSP plane is a very fast and heavy aircraft relative to the real world.

223MPH was pretty much exactly the Shuttle's touchdown speed, BTW. See http://www.nasa.gov/mission_pages/shuttle/launch/landing101.html

Concorde and the Tu-144 also came down at about 100m/s.

Edited by Wanderfound
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Ok, to set spoilers and flaps.

1. Right click the control surface you want to use. Choose Use as spoiler/flap.

2. Set and action group to control them, I use 1 for Increase Flap, 2 for Decrease, 3 for toggle spoilers, but you can use whatever you want.

3. By default brakes will activate spoilers but I recommend removing that. You don't always want spoilers and brakes at the same time. The spoiler can help you pitch the nose up but you wheels shouldn't be braked right as you touch down. Worse still if you use a custom group for spoilers and then turn on brakes, they turn back off when you want them. So remove them from brakes.

Finally, yes 100m/s is fine. Some of my SSTO's will not land at less than 150m/s because I can't keep the nose up any lower. However, that is a small runway. So you can either slow down more or use Real Chutes to stop before you plow into the hill at the other end (just like the Space Shuttle!) Just make sure you configure them, they are configured by switching to action group mode and clicking them. There you can set them to deploy on touchdown and to be drag chutes instead of main chutes for rocket pods. Also since your probably taking off from the KSC and landing on the island, make sure you set them to calculate from Wet Mass (i.e. a full tank of fuel).

When I right click on the part it does not give me that option. All I get is to activate or deactivate pitch, yaw, and roll.

Here is a pic of the craft and shows what I get when I right click on the control surface

http://cloud-4.steampowered.com/ugc/531745346181440979/675EA518073C1FE6DA17929CE268D0DE3BFA20FC/

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I've been playing KSP for a while now and just recently started getting into planes and space planes. I made a very basic plane out of stock parts and it flies great and everything but it almost seems too stable. I am on my 7th attempt of taking off and trying to land it the island runway. The problem is that no matter what I try I cant seem to lose speed. I come in from I would guess 25-30 KM out lined up with the runway at about 500-1000 meters up at a speed of around 100 m/s.

My engines are completely cut off and I have been trying to bank up to get wind resistance to increase drag to drop my velocity. Well that does work but I gain altitude. The instant I level out my artificial horizon my craft starts dropping somewhat but then my velocity increases basically right back to where I started making this never ending frustrating loop. It seems if I can fly forever with no thrust this way.

Is there something I'm missing in order to slow myself down? Any help would be appreciated. Thanks.

P.S. I do run some mods most notably FAR which may be affecting this. I do not have any parts packs that have air brakes although I am considering getting after this just because it is so frustrating.

That's weird.

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When I right click on the part it does not give me that option. All I get is to activate or deactivate pitch, yaw, and roll.

Here is a pic of the craft and shows what I get when I right click on the control surface

http://cloud-4.steampowered.com/ugc/531745346181440979/675EA518073C1FE6DA17929CE268D0DE3BFA20FC/

That's buggy, then; most likely caused by an archaic version of ModuleManager somewhere in your Gamedata directory, blocking the FAR tweakables.

You should only have one copy of the ModuleManager dll installed, and it should be the latest one.

Do you have Kerbpaint? That has a very old copy of MM buried in a subfolder.

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I'm not a real life pilot, so I could be wrong on a few of these, but here are a couple tips that have helped me in flight sims (mostly DCS):

Firstly, you might be going a little too high for such a short hop. 2km altitude is more than 6000 feet. In comparison, a typical final approach (when you're lined up with the runway and descending to touchdown) starts at an altitude of around 3000 ft AGL (above ground level), or 1km. A good glide slope (the angle at which you descend from altitude to touchdown) is a mere 3 degrees. I'm sure you can descend at 20 degrees in KSP, but that would be insane IRL. You're going to want to start your final approach from about 17 km away.

Secondly, I know it sounds counter-intuitive, but pitch your nose up about 3 degrees and control your airspeed with pitch angle. Control your rate of descent with the throttle. It really depends on the aircraft design, but you want to be descending at 3 degrees (prograde marker 3 degrees below horizon) while your nose is pitched up a few degrees above the horizon line. Airspeed could be as low as 66 m/s for aircraft designed for slow speeds (the A-10 "Warthog" lands at 130 knots, or 66 m/s), but I can get away with 100 - 120 m/s in most of my aircraft designs, which are low aspect ratio supersonic jets.

Airspeed too fast? Nose up. This will make you gain altitude and slow down. To counter the gain in altitude, drop your throttle. Eventually, your airspeed will slow and your altitude gain will turn into altitude loss.

Losing altitude too fast (i.e. your prograde marker is lower than 5 degrees)? Throttle up. You might also have to pitch up to keep your airspeed down as a result of your increased thrust.

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Now that I see a picture of the plane, it looks like a light and speedy design. The turbojet tends to be slow in its response to throttle changes. Kerbal aerodynamics are weird at best. Keep trying to find that ideal flight path and pop a drogue chute on touchdown so you can slow down enough for your brakes to work.

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Oh I just saw the picture too. Your going to run into some pitching trouble because your aielerons are very close to the center of mass. Your pitch control should be as far away as you can, either in front (canards) or in back (elevons). The pitch control acts as a lever on the plane, the center of mass is the fulcrum.

Your wings are also very large for a plane that small. Rather than changing the wings I would add another fuel tank to the rear to lengthen the plane and also empty the first two tanks to shift weight a bit, you don't need that much fuel for this trip anyway. Then add some of the active winglets around the engine area. Finally, using FAR, set the aielerons you have there to do only roll, the winglets by the engine to do only pitch, and your vertical stabilizer on the tail to do only yaw (which is not required at all for flight btw). For a plane like that I can't imagine you really even needs spoilers or flaps.

Here is a picture of a plane I made a while back, it's very similar to yours plus the changes I mentioned above. Though for a beginner, you may want to keep the wheels where you have them. This one can be touchy on landing. Just make sure they stay in line with the center of mass for lift off.

DFC376121963D4629621C076C0742BB504E7924E

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First, maybe my problem is with the module manager. When installing mods I just put in whatever they have in the package but I can imagine that I possibly put in an older one and over wrote a newer one considering some of my mods are no longer being serviced. A link to the most recent version would be appreciated. :D

Second. Although I've landed and returned on 75% of the planetary bodies in the system (rockets were never my problem). I do have to say I've never understood what "drogue chute" has meant :( . Is that a non fully deployed chute? So basically set the chute to fully deploy at 0 altitude? Get the drag without ripping me apart?

Third. SRV had mentioned that I have a light and speedy craft. Yes its true. I don't know if this design is called a turbo jet or if they think I'm using a turbojet engine. All I have is the basic jet engine to clarify if it was a misunderstanding.

Forth. Just out of curiosity. From the description, the spoiler that I am trying to do is called flaring in real life terms, correct?

and lastly fifth. Thank you all again for your help. It has greatly improved my knowledge of this game which I thought I was pretty good at. Turns out I'm still a noob. Oh well. All the intricate aspects of this game are what make it so great and with an incredible community like this is what keeps it going so long.

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Current ModuleManager: http://forum.kerbalspaceprogram.com/threads/55219-Module-Manager-1-5-6-%28Jan-6%29

Very many mods use the MM dll, and a lot of them package a copy of it with their own downloads. Normally this isn't a problem; MM is set up to ignore all but the newest version of itself. However, there are one or two MM versions that cause problems. You only need one copy of the dll; delete all but the latest one.

If the mod maker did it right, MM should be in the top level Gamedata directory so you should be able to find them easily. Unfortunately, not everyone did it right; see Kerbpaint for example. That one has a seriously archaic copy of MM buried several layers deep in its folders.

Just go to your Gamedata folder, search for ModuleManager in all subfolders, and delete them all. Then put one copy of the latest ModuleManager dll (2.3.4 at the moment) in the top level of the Gamedata folder.

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