How make my plane to take-ff without crashing?

[Pawelk198604]

 

[Geonovast]

Two main problems I'm seeing is that your CoT is above your CoM, which will push the nose to the ground, and your rear landing gear is way too far back.  You want it just barely behind the CoM.

I also would not recommend angling the rear wheels like that.  Straighten the rear gear out and offset them a bit out so they look like they're attached to the wings.  Also disable the steering on the rear gear.

 

That's a lot of thrust for that little thing.  Just use the wheezy for takeoff.  Even after you get it in the air, the panthers are going to be a problem.

[HebaruSan]

After you fix what @Geonovast pointed out, you'll need some pitch control, which is a set of control surfaces somewhere that can function to tilt the plane up and down. Usually this is either a tailplane at the back or canards at the front. Your current control surfaces are too close to the center of mass to perform this function.

[Pawelk198604]

2 hours ago, Geonovast said:

Two main problems I'm seeing is that your CoT is above your CoM, which will push the nose to the ground, and your rear landing gear is way too far back.  You want it just barely behind the CoM.

I also would not recommend angling the rear wheels like that.  Straighten the rear gear out and offset them a bit out so they look like they're attached to the wings.  Also disable the steering on the rear gear.

 

That's a lot of thrust for that little thing.  Just use the wheezy for takeoff.  Even after you get it in the air, the panthers are going to be a problem.

so how perfect CoT and CoM equilibrium should look like?

Designing rockets are so much easier    

[Geonovast]

Just now, Pawelk198604 said:

so how perfect CoT and CoM equilibrium should look like?

Designing rockets are so much easier    

It's been my experience that it's best directly in line with the CoM, or slightly below.

Having it above the CoM can work, but generally on larger craft with a ton of control authority. 

[Pawelk198604]

1 minute ago, Geonovast said:

It's been my experience that it's best directly in line with the CoM, or slightly below.

Having it above the CoM can work, but generally on larger craft with a ton of control authority. 

I need to have plane with 3 engines, because one contract testing J-404 "Panther" above 13 000 meters with speed about 450 m/s if i remember correctly.

 

So i need two J -404 Panther on each side of fuselage and one main that i would use to climb to those 13000 meters.

 

But how to do it that is a question?  

[Geonovast]

1 minute ago, Pawelk198604 said:

I need to have plane with 3 engines, because one contract testing J-404 "Panther" above 13 000 meters with speed about 450 m/s if i remember correctly.

 

So i need two J -404 Panther on each side of fuselage and one main that i would use to climb to those 13000 meters.

 

But how to do it that is a question?  

I would use a rocket.

[Pawelk198604]

1 hour ago, Geonovast said:

I would use a rocket.

A rocket?

Never mind , Val fulfilled the contract and squashed Jebediah speed and altitude record, but he insist that he at lest land plane in one piece

 

Edited June 19, 2019 by Pawelk198604

[Atkara]

4 minutes ago, Pawelk198604 said:

Never mind , Val fulfilled the contract and squashed Jebediah speed and altitude record, but he insist that he at lest land plane in one piece

I was going to send you the following craft I made in a hurry, but you got it done so, good job. Take a look at it though, grab some ideas for the future

[Goody1981]

Also, when you’re surface-attaching parts and trying to get them straight (like you were with the tail fin) use angle snap (the icon at the bottom left, next to symmetry, you can click it to change from a circle to a hexagon. Good for aligning things at the perfect angle

Edited June 21, 2019 by Goody1981

[Vanamonde]

This question about how to play the game has been moved to Gameplay Questions. 

[Pawelk198604]

14 hours ago, Atkara said:

I was going to send you the following craft I made in a hurry, but you got it done so, good job. Take a look at it though, grab some ideas for the future

You plane certainly looks more smother and more elegant than mine  , could you share you plane craft file with me? 

13 hours ago, Goody1981 said:

Also, when you’re surface-attaching parts and trying to get the straight (like you were with the tail fin) use angle snap (the icon at the bottom left, next to symmetry, you can click it to change from a circle to a hexagon. Good for aligning things at the perfect angle

Angle snap?

[Atkara]

1 hour ago, Pawelk198604 said:

You plane certainly looks more smother and more elegant than mine  , could you share you plane craft file with me?

There you go. Read the description and the action group info (I suspect you might have to enable full action groups in the difficulty settings)

Other than that, it uses parts you've already unlocked in your tech tree. So you're good to go  

1 hour ago, Pawelk198604 said:

Angle snap?

Do what @Goody1981 told you and you'll see for yourself what angle snap is

Edited June 20, 2019 by Atkara

[Pawelk198604]

2 hours ago, Atkara said:

There you go. Read the description and the action group info (I suspect you might have to enable full action groups in the difficulty settings)

Other than that, it uses parts you've already unlocked in your tech tree. So you're good to go  

Do what @Goody1981 told you and you'll see for yourself what angle snap is

Thanks  

So angle snap is more precise? 

[Atkara]

30 minutes ago, Pawelk198604 said:

So angle snap is more precise? 

It isn't more precise, it IS precise. Try it -you'll see for yourself.

[KerbMav]

Times ago someone made a plane guide full off colorized sketches that was generally regarded as very helpful and also explained lots of terminology making it easier to discuss this topic on the forums.

[Pawelk198604]

I wonder what i would need to send my plane above 70 000 meters  

[Atkara]

On 6/21/2019 at 4:06 PM, Pawelk198604 said:

I wonder what i would need to send my plane above 70 000 meters  

• Replace the central panther with a rocket engine -and the central fuel tanks obviously, since you'll need oxidizer.
• Takeoff, pitch up to 45 degrees and engage afterburners on the panthers. You'll be climbing on the panthers alone. The rocket engine will be used later.
• As you climb, right click on either of the two panthers and monitor it's thrust. When it drops below 50KN, now is the time to stage the rocket engine. Monitor your apoapsis for engine cutoff.

As far as my plane goes, after a few modifications and a number of test flights, it even reached a stable orbit.

More pictures here, in case you think I'm trying to pull your leg or something.

Once in orbit, it has barely enough fuel for a de-orbit burn -but hey, it can get up there. Haven't tried a re-entry yet, but I suspect it will be... not so nominal It re-enters like a champ and I should learn to have more faith in my designs   

Edited June 22, 2019 by Atkara

[Daniel Prates]

@Pawelk198604 the truth is that your design looks very cool, but is very impractical

All that mass concentrated too high up, with those tiny, close together landing gears...

Think of an elephant sitting on top of a shopping cart. If you push it hard against its head, its going to tip over instead of rolling foward. 

Everything needs to be lower. Then, make the CoT pass through the CoM so that it does not push the nose down. Then check if the main gears have stearing turned off (leave stearing on only in the frontwheel), and move them foward as close as possible to the CoM, just a little behind it. 

Most planes flip and crash on the runway for infringing two basic rules: 1. Most weight has to be placed on the main landing gears and off the steering wheel; 2. when thrust pushes your plane, that force has to be foward and not foward plus downwards. Correcting the two will usually do the trick.

Edited June 23, 2019 by Daniel Prates

[Kryxal]

I'd like to point out that you can use a test engine for lifting purposes ... just activate it via right-click menu, and stage it once you're ready to finish it.