KSP why my plane doesn't want to take off ?

[Pawelk198604]

I'm not good in constructing planes, but i want to start learning, so i invest my tech in some basic plane tech.

[Taki117]

Looks like you only have a single tail wheel, which, when you pitch up is becoming unbalanced causing you to roll and destroy the wing.

[Belphegor]

if you can relocate the front wheels to just in front off the center of mass, i think your single rear wheel design might be more stable on take off.. might.. but it might also tip forwards and crash while landing.

maybe you can avoid stress on the rear wheel by not touching the pitch until you have good speed and lift. if i remember correctly, in the movies the single rear wheel of those WWI/WWII fighters always cleared the ground before the front wheels. probably to avoid the problem you are having

Edited August 20, 2014 by Belphegor

[tychochallenge]

1. Seems like you don't have enough lift. Try and experiment with larger wings/control surfaces.

2. You are using swept wings. Swept wings add speed (which is sometimes good) but not a lot of lift.

3. Balance out the center of lift and center of mass in SPH. Make sure your center of lift is slightly ahead of your center of mass, but not much, or your plane will flip during flight.

4. Use ferram aerospace or NEAR. Vastly improves aerodynamics by implementing a more realistic flight model so wings and nosecones don't produces as much drag as in stock game.

5. Add MOAR STRUTS. right before you crashed, your fuselage had a little wobble which caused your plane to 'crash'.

6. Couldn't see the front of the plane, but its better if you have an additional reaction wheel.

7. Add more tail wings. Along with SAS, they'll control your plane as you pitch up

[Mesons]

I'm not good in constructing planes, but i want to start learning, so i invest my tech in some basic plane tech.

I apologize for any offense, but I find the ending of your video hilarious, mostly because it looks like the fate of my first dozen or so planes. I highly recommend reading through this guide. It really got me off the ground running when I discovered it, which was nice because I love to build and fly planes/spaceplanes in KSP in spite of the poor aerodynamic model.

[capi3101]

Yeah, you've got what Keptin calls a "tail-dragger" gear setup. For your first couple of designs, you might want to flip that around into a "tricycle" setup, where the single wheel is up front and you've got two wheels in the back.

Just in case you've never seen it - http://forum.kerbalspaceprogram.com/threads/52080-Basic-Aircraft-Design-Explained-Simply-With-Pictures

It's a good introduction to spaceplane design.

EDIT: And Mesons beat me to it...

[Moonfrog]

for attaching the wheels, since I can't see how u attached them. I recommend doing this. If you attach them to wings, use the attach option who's Icon looks like a circle. When attaching onto fuselage or fuel tanks use the hexagon Icon symbol. This should at most keep them at a straight angle. I've had wobbly results doing it differently. Other things have been mentioned in above posts.

Also if your lift is in front of the centre of mass. It might lift up your first two wheels when it tries to take off. This would cause your plane to attempt to balance on one wheel, cause instability. I can't see where your lift is. This might be it, or not.

Another tip is to use less powerful control surfaces, they tend to act more jerkier than SAS, so if u have a powerful control surface on a light plane, when the sas moves it a little, it will move a lot, then a lot more to compensate, then even more to compensate causing massive wobbles.

Another problem is parts wobbling and moving. usually when u add two wings together, or fuel tank to a hardpoint then to a fuel tank. The strong force of control surfaces can cause them to wobble quite easily. Placing struts on fuel tanks or wings can help this. You only need to add one strut from one part to different part its not connected too already.

I can't really tell from what you've shown me, if u could give a picture with its lift, centre of mass and thrust in the SPH.

Edited August 20, 2014 by Moonfrog

[Pawelk198604]

I apologize for any offense, but I find the ending of your video hilarious, mostly because it looks like the fate of my first dozen or so planes. I highly recommend reading through this guide. It really got me off the ground running when I discovered it, which was nice because I love to build and fly planes/spaceplanes in KSP in spite of the poor aerodynamic model.

[GoSlash27]

#1) right click on your ailerons and set them so that they are not responding to pitch and yaw inputs.

#2) put a little dihedral in your wings so they naturally tend to seek level flight

#3) make sure your nose is a little higher than your tail so you're generating lift at takeoff

That should get you off the ground in one piece. After that... we'll see what we see.

Best,

-Slashy

[O-Doc]

Don't listen to the h8erz, tail-draggers rule! Your front gears need to be just forward of your CoM and the rear gear right up the back. Mount your rear gear on a cubic strut so most of your the gear is inside the fuselage*, ergo, your plane will take off without having to pull back on the stick. Check out WWII designs, they all nose up naturally.

One more thing, brakes and steering on the rear gear only or your kerbal is going to have a bad day.

*My catalogue has a number of examples of the gears tucked into the body using cubic struts.

[Kasuha]

Putting rear wheel higher than tail wheel usually means your plane will be dropped on the runway from higher point ... and it may break. Personally I perfer having rear wheels wide and just behind CoM, and mounting some canards, giving the nose its separate lift for takeoff. It's about the easiest way to get a plane up from the runway but you must watch to not move your center of lift too much to the front. If you have a long tail, you may want to clip one more wheel into it, positioned high enough that it just sticks out of the fuselage. It's not there to prevent the plane pitching up, it's there to prevent it breaking off its tail should you pitch too much.

In any case, I recommend watching Scott Manley's aircraft tutorials:

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[Mesons]

Nice landing there!

[WololoW]

#2) put a little dihedral in your wings so they naturally tend to seek level flight

Can you clarify that? I understand what a Dihedral angle is, but not what you mean to convey by saying "put a little [angle between two planes(dimensional planes)] in your wings"

[GoSlash27]

Can you clarify that? I understand what a Dihedral angle is, but not what you mean to convey by saying "put a little [angle between two planes(dimensional planes)] in your wings"

A picture is worth a thousand words

-Slashy

[WololoW]

Much appreciated Slashy~