Do Mark 16 XL work Slowing down on Duna?

[Mukita12]

So I'm back okay that's good back to the topic ###### so i have Question do Mark 16 XL chute work slowing down, Stabilize and Space craft/Rover/Lander If work then I can Launch my Dunarian Rover to Dunarian Surface

 

 

 

PS.Sorry for Bad Grammar

[Zhetaan]

Parachutes work on Duna; they just don't work well.  They are usually worth the mass to take them, but they often don't slow you down enough on their own to prevent crash damage.  For this reason, you ought to take both parachutes and descent-stage rockets to ensure a trouble-free landing.

If you really want to land your rover on parachutes alone, make it as light as possible and remember that because there's so little air on Duna, you will need a lot more parachute than you're used to providing for Kerbin landings.

[Cpt Kerbalkrunch]

Drogue chutes are highly recommended. As @Zhetaan pointed out, the air is very thin. You can still make unpowered landings with chutes and airbrakes alone (amount needed depending on your mass), but it's tough to slow down enough for your main chutes to open. Drogue chutes work great in this regard, as they open at a higher speed. Alternatively, you could use your engines  to slow down a bit if you have fuel to spare.

[Spricigo]

you probably have heard of Goldilocks Principle  when something is not too much or not too few but 'just right'.

Well, Duna Atmosphere (like its real life counterpart) resting in the baby bear zone, not dense enough for landing only with parachutes, not thin enough for a purely propulsive landing, but just the wrong atmosphere. Goldilocks screw with you every time.

[fourfa]

I generally use just a small drogue chute or two, and use retropropulsion to slow down the last 50m/s or so.  The mass of fuel needed is pretty similar to the mass of parachutes needed to slow all the way down, and all that dead mass of chutes reduces your dV in other flight regimes like transport, rendezvous, and docking.

[Mukita12]

okay now i have my answer i think i use some separator to Make it nice and soft Landing xd

Edited July 25, 2017 by Mukita12

[Spricigo]

11 hours ago, Mukita12 said:

okay now i have my answer i think i use some separator to Make it nice and soft Landing xd

Another method is to have "bumpers" that can survive impacting at higher velocity (e.g. Girder segment). 

And while that is clear not the intended purpose fairings are virtually indestructible (but not the base) 

[Mukita12]

6 hours ago, Spricigo said:

Another method is to have "bumpers" that can survive impacting at higher velocity (e.g. Girder segment). 

And while that is clear not the intended purpose fairings are virtually indestructible (but not the base) 

what about twitch engine?????

[Spricigo]

13 hours ago, Mukita12 said:

what about twitch engine?????

Maybe too powerful. It really depends on the weight of the rover and amount of parachutes used. After all it don't need to be able of a complete stop, just slow down enough for a safe landing.

I'd use the cheat... test menu to experiment a bit. My first bet would probably be a parachute and 2 spider engines.

[Cpt Kerbalkrunch]

1 hour ago, Spricigo said:

Maybe too powerful. It really depends on the weight of the rover and amount of parachutes used. After all it don't need to be able of a complete stop, just slow down enough for a safe landing.

I'd use the cheat... test menu to experiment a bit. My first bet would probably be a parachute and 2 spider engines.

I've used the Twitch and the Spider, but both would require a bit of fuel (though only a very little). If you want an unpowered landing, I think two drogues and a regular chute would do the job (numbers depending on the size of the rover, of course).

[Spricigo]

1 hour ago, Cpt Kerbalkrunch said:

I've used the Twitch and the Spider, but both would require a bit of fuel (though only a very little). If you want an unpowered landing, I think two drogues and a regular chute would do the job (numbers depending on the size of the rover, of course).

Out of curiosity,  how much the rover weighted?  And how fast it touched down? 

BTW: 2x drogue chute 150kg

2x spider engine 40kg, OscarB tank(empty) 25kg,  Fuel ?? 

Seems like a close call. 

[Alshain]

On 7/24/2017 at 4:37 PM, Spricigo said:

you probably have heard of Goldilocks Principle  when something is not too much or not too few but 'just right'.

Well, Duna Atmosphere (like its real life counterpart) resting in the baby bear zone, not dense enough for landing only with parachutes, not thin enough for a purely propulsive landing, but just the wrong atmosphere. Goldilocks screw with you every time.

You are looking at it backward.  Duna's atmosphere isn't thick enough you have to worry about heat shields, but it also isn't thin enough that you have to do a complicated vacuum landing.  It's perfect really.  It never screws with me.

[Cpt Kerbalkrunch]

49 minutes ago, Spricigo said:

Out of curiosity,  how much the rover weighted?  And how fast it touched down? 

BTW: 2x drogue chute 150kg

2x spider engine 40kg, OscarB tank(empty) 25kg,  Fuel ?? 

Seems like a close call. 

I guess it would be. I'm probably misinterpreting the thread. I was talking about making an unpowered landing. Whether it saves me anything or ends up costing more, I don't really pay attention to; so I'm not sure. I do it just cuz it's kinda cool.

For specifics, it's been awhile since I've landed a rover that small, so I don't have those numbers. I just dropped a larger rover for the Landing on Duna Challenge, but I went overboard on that one. Didn't test it, so I wanted to be sure it would land alright. I used 4 regular chutes and 3 drogues. It was obviously unnecessary. Landing took forever (even with physics warp) at a 2m/s crawl.

[Spricigo]

59 minutes ago, Alshain said:

You are looking at it backward.  Duna's atmosphere isn't thick enough you have to worry about heat shields, but it also isn't thin enough that you have to do a complicated vacuum landing.  It's perfect really.  It never screws with me.

Well,  I admit my statement used a bit of rethorical emphasis (aka exaggeration) .

In any case Duna may not be difficult but is awkward.  If you are trying to find the 'most efficient way'  to do things in Duna,  there will be a lot of headscratching. 

[Mukita12]

7 hours ago, Spricigo said:

Out of curiosity,  how much the rover weighted?  And how fast it touched down? 

BTW: 2x drogue chute 150kg

2x spider engine 40kg, OscarB tank(empty) 25kg,  Fuel ?? 

Seems like a close call. 

I haven;t see the weight yet