REQUEST: Could someone make this plane fly?

[jadebenn]

So I have a problem. While this plane can fly with all it's kethane tanks empty, once they're full it cannot fly. Could someone redesign the plane so it can fly when full?

Mods Required: Kethane

Craft file:

https://mega.co.nz/#!kx1znAJC!FKIw6E8QZMuuWVE-ZuMy0E09WUMnBx0P9BdeaCPmd0Q

Thanks in advance

Edited August 12, 2013 by jadebenn

[deskjetser]

A picture would be helpful if you want to get this done.

And i'm really not sure what thing in particular your design isn't doing right, but just try adding more wings. The Kerbal aerodynamics are cheesy at best so don't be afraid to experiment.

[jadebenn]

A picture would be helpful if you want to get this done.

And i'm really not sure what thing in particular your design isn't doing right, but just try adding more wings. The Kerbal aerodynamics are cheesy at best so don't be afraid to experiment.

Well my main problem is that adding more lift as far as I have done hasn't helped much. I think there's a way but I'm not very good at space-planes and I'm just kinda stuck. I was hoping someone more knowledgeable could redesign the wing structure.

[deskjetser]

Put up a picture of it

[jadebenn]

Put up a picture of it

Done

10char

[Amphiprion]

put keth +fuel storage either side of the COM/COL and use tac fuel balancer

Edited August 12, 2013 by Amphiprion

[jadebenn]

put keth +fuel storage either side of the COM/COL and use tac fuel balancer

Do you mean by adding radial tanks?

[Exothermos]

OK, so I think some spaceplane basics are in order here.

If the entirety of that fuselage is a full kethane tank, you are going to need a LOT more wing surfaces, and a ton more thrust. Is this supposed to lift off of Kerban or Duna or Laythe? If it's kerban you need a huge wing. Easily 5x what I see there, and you will need about 8x jets (or more). If it is Duna, you need another set of aerospikes and a similar large wing.

I'm going to do a build with stock parts that mimic the size of your ship here, but this is not intended to be a craft that will actually work. Merely it is to illustrate building techniques and the scale at which you must think.

Take everything off of your plane except the fuselage you want to lift. Try to arrange your parts so that the Center of Mass Icon is close to the center of your Refillable Kethane tank. The tank is your payload, and the payload should always be at the center of mass.

Use a structural part (like the fuselage) to start tacking engines on. Do your self a favor and keep things simple for now, only add engines dead center on the horizontal plane, near the back (use snap symmetry).

Now it's time to add fuel for your engines. Put the tanks on the horizontal as well, except this time make sure they are dead centered on your Center of Mass. Run Fuel lines from your tanks to the engines. Strut the contraption up.

Now you need lift. Lots of it. The easiest way on a large fuselage like that is to go for a Biplane style wing. Turn your center of lift Icon on, turn off snap symmetry and start adding wing structural panels to the fuselage above your fuel tanks. I came up with this design. Do what you feel like. The result should be a large wing with a Center of Lift directly behind the CoM.

Now flip everything over and use alt-click to copy your top wing and paste it on the bottom. Now you have a wing that might be big enough. Maybe. Strut everything together.

Add your landing gear. Some up front and the rear gear should be just behind the center of mass, not way at the end of the fuselage. Add some intakes (except for duna, obviously). The more you have, the the better.

Test it! Did I mention to strut things up?

[Tyren]

This is the best heavy lifter quick guide ive seen...and i ve seen a lot of them

[jadebenn]

OK, so I think some spaceplane basics are in order here.

If the entirety of that fuselage is a full kethane tank, you are going to need a LOT more wing surfaces, and a ton more thrust. Is this supposed to lift off of Kerban or Duna or Laythe? If it's kerban you need a huge wing. Easily 5x what I see there, and you will need about 8x jets (or more). If it is Duna, you need another set of aerospikes and a similar large wing.

I'm going to do a build with stock parts that mimic the size of your ship here, but this is not intended to be a craft that will actually work. Merely it is to illustrate building techniques and the scale at which you must think.

Take everything off of your plane except the fuselage you want to lift. Try to arrange your parts so that the Center of Mass Icon is close to the center of your Refillable Kethane tank. The tank is your payload, and the payload should always be at the center of mass.

Use a structural part (like the fuselage) to start tacking engines on. Do your self a favor and keep things simple for now, only add engines dead center on the horizontal plane, near the back (use snap symmetry).

Now it's time to add fuel for your engines. Put the tanks on the horizontal as well, except this time make sure they are dead centered on your Center of Mass. Run Fuel lines from your tanks to the engines. Strut the contraption up.

Now you need lift. Lots of it. The easiest way on a large fuselage like that is to go for a Biplane style wing. Turn your center of lift Icon on, turn off snap symmetry and start adding wing structural panels to the fuselage above your fuel tanks. I came up with this design. Do what you feel like. The result should be a large wing with a Center of Lift directly behind the CoM.

Now flip everything over and use alt-click to copy your top wing and paste it on the bottom. Now you have a wing that might be big enough. Maybe. Strut everything together.

Add your landing gear. Some up front and the rear gear should be just behind the center of mass, not way at the end of the fuselage. Add some intakes (except for duna, obviously). The more you have, the the better.

Test it! Did I mention to strut things up?

Thanks for the tips I'll see how it goes remaking the plane.

[Jetenginestar]

Add your landing gear. Some up front and the rear gear should be just behind the center of mass, not way at the end of the fuselage. Add some intakes (except for duna, obviously). The more you have, the the better.

Why not at the end of fuselage, I thought adding it near the tail can allow you to have higher AOA (pitch) when landing?

[Jetenginestar]

Add your landing gear. Some up front and the rear gear should be just behind the center of mass, not way at the end of the fuselage. Add some intakes (except for duna, obviously). The more you have, the the better.

Why not close to the tail ?

[Exothermos]

Because if you put the wheels at the end of the fuselage, they will be very far away from the center of mass of the ship. It's a classic lever-arm concept like a seesaw. Your rear wheels are the fulcrum of the lever arm, like the center of a seesaw. If you move the fulcrum (rear wheels) too far backward, it's like making one side of the seesaw really short, meaning that you need a huge amount of force to lift the weight on the long side (everything forward of the rear wheels). Make a quick plane ( or play with the stock ones) to test what I mean. Try it with the wheels right behind the CoM, and try it with the wheels all the way at the back.