Powered landing (with ascent stage)

[Omnivore]

I asked my neighbor about this and she said I needed professional help. Not sure if this is what she meant but here I am turning to the professionals.

I\'ve been trying to do powered landings, having watched a couple videos and read a few tips, I designed my ideal vanilla lander/ascent craft as:

However, my best attempts to land have had this result:

So then I tried a more realistic design:

The results weren\'t much more encouraging:

Finally after a few zillion attempts, I had a success - touchdown was at around 3 to 4 m/s.

Does anyone know the maximum vertical touchdown speed before things start blowing up?

Another problem I\'ve run into is throttle locking at full thrust on a bounced touchdown.

So I\'m looking for assistance, suggestions, tips, pointers, a clue, breadcrumbs, friendlier neighbors, anything!

More info: I use the triple SRBs in both designs for gaining initial altitude as well as for makeshift landing gear, in a Mun shot the SRBs would probably be fired as part of an initial orbital insertion maneuver. The goal is a landing where the upper stage (para + pod + LFT + LFE) survives to take off again.

I\'m aware of the following tips:

• 
  [li]When braking, apply thrust between center of ball and reverse vector indicator (yellow O with X) to kill horizontal velocity.[/li]
  [li]Using RCS to assist in killing horizontal velocity as well as fine tuning vertical velocity.[/li]
  [li]Using winglets to stablize landers in atmosphere[/li]
  [li]Turning the camera so as to be able to see the ship\'s shadow during final approach as it gives a better indication of altitude than the altitude above sea level meter.[/li]

I\'ve had enough success with the thrust vectoring during initial braking to avoid most horizontal velocity problems - especially when an ASAS module is in the stack so haven\'t been using RCS. I\'ve been avoiding winglets since I have my eye on an eventual Munar landing.

My major problem is that even with having less than 10m/s during touchdown events all my LFEs and LFTs assplodey.

Heh, after avoiding winglets as stabilizing devices, I\'ve found they make great landing gear on my lightest weight successful design thus far, the Bizzaro I:

[Mice!]

Try this.

[Omnivore]

Nicely done! Were you able to take off again?

[Mice!]

It\'s not my rocket (/v/ made it), but yes. It didn\'t have enough fuel to escape the moon though.

Here\'s his thread: http://kerbalspaceprogram.com/forum/index.php?topic=3697.0

[foamyesque]

It\'s not my rocket (/v/ made it), but yes. It didn\'t have enough fuel to escape the moon though.

Here\'s his thread: http://kerbalspaceprogram.com/forum/index.php?topic=3697.0

That\'s \'cause radial decouplers are ridiculous heavy. =(

[Millitron]

That\'s \'cause radial decouplers are ridiculous heavy. =(

So with a little fine tuning of the staging, you could ditch the radial decouplers on the moon, and have plenty of fuel for a return trip.

Give the radial decoupler\'s their own stage between the final stack decoupler, and your engine, and you\'re good to go.

[Omnivore]

The best, as far as I\'m aware, \'landing gear\' available for vanilla is a triplet of radial decouplers and AV-R8 winglets. They mass 33% more than empty SRBs welded on but have the *big* advantage of giving a nice bit of ground clearance to the new thrust vectoring LFEs. A few people besides myself have used them successfully in Munar landings.

One thing I\'m not sure of though is how much drag and mass you lose when you activate a radial decoupler? All of it? Same questions with struts.

[Millitron]

The best, as far as I\'m aware, \'landing gear\' available for vanilla is a triplet of radial decouplers and AV-R8 winglets. They mass 33% more than empty SRBs welded on but have the *big* advantage of giving a nice bit of ground clearance to the new thrust vectoring LFEs. A few people besides myself have used them successfully in Munar landings.

One thing I\'m not sure of though is how much drag and mass you lose when you activate a radial decoupler? All of it? Same questions with struts.

I think for struts it depends on which end you click. Like, the strut mass is located at the first place you place it. So if you start it on your main stack, it stays with you; but if you start it on the stage which will be jettisoned, you jettison it along with the rest of the stage.