Aerobraking

[DuartePires]

Hi there, I'm using FAR and Deadly Reentry, and real chutes. I've just setup a spacestation on Kerbin orbit, after I went there with a MK2 and 3 kerbals there, when I try to get back home my reentry doesn't stop me early enough to deploy parachutes!!

I've tried setting a lower orbit but it won't go slower, I enter 2400ms and about 10km I'm still at 1500ms+.

My vessel also carrys some food and science stuff is it because of it's heaviness?

[Mitchz95]

If you're still going 1500m/s at ten kilometers from the ground, something is definitely wrong. No idea what, though.

[UnthinkableThinker]

For aerobraking, all you need is to set your periapsis to an altitude that the atmosphere starts to kick in and reduces your speed. What I do is I set my periapsis to 24km (For Kerbin), which gives me plenty of aerobraking, for small or large vessels.

[Taki117]

If you're still going 1500m/s at ten kilometers from the ground, something is definitely wrong. No idea what, though.

i agree, unless you're using RSS and coming in almost dead vertical you shouldn't be going more than about 700m/s at 10km, which means that if you're going 1.5km/s at 10km I'm surprised you're still alive with DRE.

[RainDreamer]

How high did you drop down from? I usually have my apoapsis below 100km and periapsis at about 30km for reentry on stock kerbin.

[Randazzo]

Need a picture of your trajectory or something. There's no way you should be going that fast just from LKO unless you have an engine thrusting you toward the ground.

[EdFred]

When I experimented with FAR, I had this issue when my vessel was *too* aerodynamic. I had issued with the spontaneous disassembly, so I figured 'hey, I will keep it in a fairing until chute deployment altitude.' Nope, came in even hotter and faster, and still got ripped apart. Once I made it more draggy, it re-entered OK - oh and got rid of the fairing too.

[Pecan]

Aerobraking may take more than one orbit. If your first doesn't slow you enough just go round again. Every time you enter the atmosphere drag will slow you down.

[DuartePires]

Yes but I'm doing 2300ms at 42k it can't seem to slow me down fast enough... My ship is not only the mk2 it's as a fairing below that carrys some food and science and below the shield...

Is it because it's heavy? 9t?

[Wanderfound]

Post a screenshot of the reentry capsule, and tell us exactly what your Ap/Pe are when you reenter. We can't diagnose what we can't see.

At reentry, your periapsis should be around 20,000m.

[DuartePires]

Sorry guys I've lost the ship trying in reentry no screenshots

I've tried launching another ship but without the cargo, so only the COM module with the shield, and now it slows down correctly... I think the last one (it weight almost 10tonnes) so maybe that0s the reason it couldn't be stoped...

But how do I send food and stuff to duna for example? Do I need to put it in various cargo and separate?

[Taki117]

Sorry guys I've lost the ship trying in reentry no screenshots

I've tried launching another ship but without the cargo, so only the COM module with the shield, and now it slows down correctly... I think the last one (it weight almost 10tonnes) so maybe that0s the reason it couldn't be stoped...

But how do I send food and stuff to duna for example? Do I need to put it in various cargo and separate?

Use Drogue chutes and retro rockets. Once you get to about 10km (5km above terrain if using Mechjeb) pop your chutes and ditch your heatshield to expose your retro rockets. I highly recommend the mod RealChute for this so that you can tell it when you want to deploy and not have to worry about it deploying early, or if you have enough chutes (If you use Realchute you don't need retro rockets) Anyway, as I was saying, use your parachutes to slow you down most of the way, then use your retrorockets to land. If you have a fairing ditch it with the heatshield.

Another option, (And one that is much more cool) is to use airbrakes (From either B9 or Firespitter, I think some others have them too) deploy those before reentry and they will help slow you down as you come in, then when you are slow enough ditch your fairing and heatshield and use retrorockets/parachutes to land.

[Wercho]

He already said he is using RealChutes.

The problem is Deadly Reentry makes chutes break (including drogue chutes) if they open going faster than about 350 m/s. With FAR I have found that my ships don't slow down enough on reentry just from air resistance if they are too heavily loaded for their size (too dense). This usually happens if I am deorbiting something with a fair amount of fuel left. I learned to burn off excess fuel, or better yet use it for retrograde burning on the descent to slow down.

To land heavy stuff on Duna with FAR, you are going to need retrorockets.

[DuartePires]

Ok by retrorocket you mean put some small like rockmax 24-27 ? to help slow down correct?

[lincourtl]

Ok by retrorocket you mean put some small like rockmax 24-27 ? to help slow down correct?

You might be able to use a couple of sepratrons as well. Tweak the thrust and/or amount of fuel as needed. If you're using Deadly Reentry, remember to keep them shielded or they'll go kaboom.

[ddenis]

One of variants, that were mention before is the trajectory of reentering. In some cases I can have AP 100 and Pe 50 and such trajectory will differently slow you enough. But maybe you was doing this... Who knows without number from you it's just an idea.

[mrfire45]

I'm not sure, but does FAR make the atmosphere thinner, so the aero-braking takes longer? To slow down, maybe just use some sepatrons?

[Taki117]

I'm not sure, but does FAR make the atmosphere thinner, so the aero-braking takes longer? To slow down, maybe just use some sepatrons?

not thinner, more realistic. You never really hit thick atmo with a well designed craft. I don't think I've ever hit Terminal Velocity with FAR.

[Xannari Ferrows]

Aerobraking is not meant to be done by plopping straight down into the atmosphere. Try moving in at a very shallow angle.