Basic (stock) VTOL design. Any tips ?

[Maukse]

Hello everyone !

Since now one year I'm Kerbaling with various success.

Now I'm pretty happy with my spaceplanes / rockets / station designs.

But designing an VTOL that can hover is still a very, very difficult task for me.

Do you have any suggestions ? I would like to create a kind of "rescue craft" (on kerbin).

Using KAS I would like to drag/drop things from/to the vessel (I would like to design it with stock parts only).

Another solution for my rescue missions would be to paradrop help from the sky.

What is the usefull mod to "drop" an item with chute and leave the zone ?

Thanks in advance !

Edited April 12, 2015 by Maukse

[ghostbuzzer7]

You want to put your vertical engines directly at the center of mass, however if you use two make sure they are equally distant from the VTOL. Secondly, your center of mass should slightly change as you run out of fuel, if not then you may encounter problems when you have low fuel. Restrict from using too many control surfaces because it often causes uneven distribution of aerodynamics. Lastly, use incline stabilizers they will significantly help. I made a VTOL myself here.

http://forum.kerbalspaceprogram.com/threads/112868-VTOL-AeroSpace-F-35-MetalStorm?p=1785385

Hope this helps

[FlipNascar]

The one tool that will help you massively is RCS Build Aid. Cannot recommend it enough, makes VTOLing so much simpler. And of course more TWR.

[capi3101]

Since you're in the stock game, I'm going to recommend DocMoriarty's KSP Spaceplane Construction and Operation Guide. It's a PDF that contains some very useful pointers for building planes in the stock game with the stock aerodynamic model - and it includes a very extensive section on how to build a working VTOL craft. The other advice you've received on this thread already is quite good; I strongly second FlipNascar's recommendation of the RCS Build Aid mod, and I would go so far to say that it's an essential mod for anyone wanting to make heavy use of spaceplanes in general (regardless of your aero model).

[Maukse]

thanks for the advices !

I think I will try again with RCS build aid.

About hovering - is there a function in mechjeb to do so ? Maybe in docking mode ? (like, zero vertical speed / zero horizontal speed)

[Maukse]

Ok, just found the "kill vertical speed" option in mechjeb - but I still have to figure out how to use it with jets engine (it's not regulating yet).

Work in progress !

EDIT : tweaking engine power and manually regulation vertical speed - I can hover (more or less) +/-10 meters around a given altitude.

Enough for KAS-based rescue system (to be designed).

Edited April 12, 2015 by Maukse

[Landge]

Try doing it without mods at first. All it takes is practice and patience. Jet engines are the hardest to control in VTOL due to their spin up/down delay...

Here is a rocket powered VTOL Mobile Base I made for Duna, landing without parachutes...

How one design can lead to others...

Testing out a VTOL Fuel Truck using only stock parts.

I've since switched to KAS because trying to dock on the ground was too much of a pain (differing gravities and uneven terrain) trying to line up the docking ports.

[Maukse]

Try doing it without mods at first. All it takes is practice and patience. Jet engines are the hardest to control in VTOL due to their spin up/down delay...

How one design can lead to others...

Testing out a VTOL Fuel Truck using only stock parts.

I've since switched to KAS because trying to dock on the ground was too much of a pain (differing gravities and uneven terrain) trying to line up the docking ports.

http://i.imgur.com/W6muM7tl.png

Yeah, a bit hard with jet engines, but if you tweak your twr to be around 1.3 - 1.4, then you can manually hover, using the throttle (at least, I managed to hover this way)

Now I'll design a "rescue pod" that I plan to "winch-drop" on any place (mountains included), to rescue kerbals. Might me manned.

The trick is, I'll have then to land with my VTOL, set an electromagnet on the winch, and go back to "drag" the rescue pod.

[Landge]

Yeah, a bit hard with jet engines, but if you tweak your twr to be around 1.3 - 1.4, then you can manually hover, using the throttle (at least, I managed to hover this way)

Now I'll design a "rescue pod" that I plan to "winch-drop" on any place (mountains included), to rescue kerbals. Might me manned.

The trick is, I'll have then to land with my VTOL, set an electromagnet on the winch, and go back to "drag" the rescue pod.

Yes, that is a pain when the optimum thrust is set in between keyboard taps. I did something similar using the grabber on a downed probe I had on the moon.

Watch out though. It could throw your CoM off. That is if you are trying to do a salvage operation.