Landing multiple landers at the same time

[Marclev]

Unfortunately I didn't get a screenshot, but was impressed enough at this actually working that I thought I'd post about it.

Came back to Kerbin from a trip to Jool with a lander attached to a science lab attached to a nuclear rocket (all detachable). Both the lander and the science lab had independent parachutes and landing legs, as the intent was always to break them up in LKO and then land them separately.

So, long story short, I got overconfident with the aerobrake and down everything went towards the surface. With no other option, I decoupled everything from each other, activated the parachutes and legs on the lander, and then flipped to the science lab and activated the parachutes and legs on that.

I was amazed to watch as they both deployed their parachutes and proceeded to gently fall to the surface in relative unison, quite close by to each other. Both made a safe landing and I was able to recover both.

So now I'm wondering how many things you could safely land like this at the same time, if you actually designed a ship around it. Has anybody tried this?

[LethalDose]

You could probably land a bunch of vessels like this, so long as they didn't drift too far apart. On Kerbin, any vessels in flight are removed from the game (just destroyed, deleted) if they are more than 2.5 km from the active vessel, so you just have to keep them close. The best way to do this I've seen is to break up the ship as close to the surface as possible.

[xtoro]

Yep, did this on Duna. You can have chutes and decouplers on the same stage so that when you decouple something, the chutes for it deploy at the same time.

I had 3 large tanks that were going to be used to store fuel, a Kethane mining rover, and a return ship all together stacked one on top of another. Brought them all into the atmosphere together, and then dropped them one by one with each stage decoupling and setting off the chutes at the same time. They all landed nicely in a row. When I was done I ended up with a nice refueling point on Duna with lots of fuel ready to fill up visiting ships while I built a base. I also dropped the parts of the base multiple pieces at a time after proving that it worked.

You could probably land a bunch of vessels like this, so long as they didn't drift too far apart. On Kerbin, any vessels in flight are removed from the game (just destroyed, deleted) if they are more than 2.5 km from the active vessel, so you just have to keep them close. The best way to do this I've seen is to break up the ship as close to the surface as possible.

This is easily solved by making sure there's a probe module on each piece. Then the game won't remove it because it's considered a ship. That's what I do.

[maltesh]

This is easily solved by making sure there's a probe module on each piece. Then the game won't remove it because it's considered a ship. That's what I do.

What he's referring to is the way that the game auto-deletes /anything/, ship or not, that's flying in Kerbin's atmosphere below an altitude of about 21 km, that is more than 2.5 km from your active craft. The similar kill line for Duna is about 8km altitude; I don't recall what it is for Eve or Laythe.

[SRV Ron]

As long as they don't get more then 2.5K away;

[JayKay]

I put down a hab lander alongside the main ship that way. I set up the chutes to deploy one after the other and separated the docking ports early. They stayed together until the main ship's chutes deployed, then the hab module dropped a short ways until its chute also opened all the way, then they drifted down within metres of each other until touching down.

[xtoro]

What he's referring to is the way that the game auto-deletes /anything/, ship or not, that's flying in Kerbin's atmosphere below an altitude of about 21 km, that is more than 2.5 km from your active craft. The similar kill line for Duna is about 8km altitude; I don't recall what it is for Eve or Laythe.

Ah. Well I've never tried them far apart, they're always together

[Wooks]

This is a really old video of mine, a round trip to get science from Duna and Ike with 6 probes and a lander, I wanted to return to Kerbin in style so I set up everything to decouple and land separately. Relevant part to the discussion starts in 8:00, no need to watch whole.

Edited November 4, 2014 by Wooks

[Aragosnat]

But, yeah. IT is fun to watch multiple ships do that at once. Had 8 Kerbals that I put in to their craft while doing a short sub-orbital hop from Kerbin long time ago. Was neat wating all 8 drop ships land so close to each other they where like a string of pearls.

[Kerano]

My current go-to launcher for a ~350 tonne payload to LKO is designed to have four separate engine sections splash down together a few hundred km from KSC. As long as they stay within the ~2.5 km physics range the parachutes always open together and the engines always survive.

One odd thing I notice from time to time though is that if one section is separated by more than ~200-300 metres from the one in current view, the post-splashdown animation (falling gently into the water, parachute disappearing) does not occur - instead the craft freezes upright with its parachute still deployed until I switch to it with the [ or ] keys. Apparently the range when applying water physics for splashed-down spacecraft is only a few hundred metres?

Edited November 4, 2014 by Kerano

[magnemoe]

Mechjeb will run on ships less than 2.3 km away, if its set to land anywhere at an set speed this should work well if you do final braking burn while using parachutes.

Not done landing this way but have docked two ships while controlling another

[Wanderfound]

Unfortunately I didn't get a screenshot, but was impressed enough at this actually working that I thought I'd post about it.

Came back to Kerbin from a trip to Jool with a lander attached to a science lab attached to a nuclear rocket (all detachable). Both the lander and the science lab had independent parachutes and landing legs, as the intent was always to break them up in LKO and then land them separately.

So, long story short, I got overconfident with the aerobrake and down everything went towards the surface. With no other option, I decoupled everything from each other, activated the parachutes and legs on the lander, and then flipped to the science lab and activated the parachutes and legs on that.

I was amazed to watch as they both deployed their parachutes and proceeded to gently fall to the surface in relative unison, quite close by to each other. Both made a safe landing and I was able to recover both.

So now I'm wondering how many things you could safely land like this at the same time, if you actually designed a ship around it. Has anybody tried this?

It takes delicate timing; I had a comparable situation where I needed to get half a dozen Kerbals out of a crippled spaceplane to descend on EVA parachutes. Arranging things so that I could get all six onto their 'chutes and to the ground without anyone leaving physics range was quite tricky, particularly as the plane only had two hatches and no ladders.

From memory, I ended up throwing the plane into a vertical climb until it stopped dead, then frantically right-clicked all over the place.

[cantab]

DasValdez was doing something like this on his stream last night, breaking his rocket into three parts for recovery.

If you do the breakup 2 km from the surface you will definitely be fine, just watch that your bits don't fall on top of each other. 2 km is also a sensible altitude to pre-deploy chutes, at least on Kerbin.

[Bishop149]

Yeah did this quite a lot when delivering multiple small things to Laythe, (rovers, supply drop pods etc)

I do it by having the stuff arranged radially on the bottom section of the section I deorbit. On the top of that section are some drogue chutes, once those have deployed and decent is relatively slow and 100% vertical I blow the decouplers holding the "lander bits" and deploy their (non-drogue) chutes at the same time. Landers will then fall away from motherdropship straight down, staying within 2.5km of each other.

Things to remember with this approach:

- Don't put a control module on the motherdropship . . . if you do you might find yourself staying with it as all your landers drop away to 2.5km oblivion. This can happen even if you change "control from here" point. Sometimes its seems the game doesn't get the message, best just to eliminate the option.

- Deploy landing legs of all the landers before decoupling them. . . . Unless you really WANT to rush around switching craft in a panic to deploy all the legs before they hit the ground . . .

[John FX]

My first Duna lander did something like this. It dropped 6 rovers, a return module that had empty tanks and a kethane miner. Worked quite well except the rovers did not quite have enough chute and so burst some tyres on landing.