Eve drop pod for Rover - keep exploding

[Jestersage]

For my AAP Eve flyby, I need to make 2 rovers. The problem is actually dropping them into Eve.

The drop pod consist of a 1.5m fairing, pure cylinder (no flare out), with one end protected by the 1.5m heat shield.

From a 9000k, My drop pod de orbit to 15k. It keep exploding. Am I doing it wrong?

Edited December 11, 2016 by Jestersage

[Foxster]

16 minutes ago, Jestersage said:

For my AAP Eve flyby, I need to make 2 rovers. The problem is actually dropping them into Eve.

The drop pod consist of a 1.5m fairing, pure cylinder (no flare out), with one end protected by the 1.5m heat shield.

From a 9000k, My drop pod de orbit to 15k. It keep exploding. Am I doing it wrong?

Could you post a picture?

[bewing]

Whether it explodes or not depends on the mass, the speed, the Pe, which end is pointing forward, and the drag.

So, what is the exact mass of the drop pod?

Are you orbital or in an escape trajectory when you drop it? Do you mean that you are orbital with a 9Mm Ap? Do you mean that you are setting the Pe to 15km?

Are you saying that it makes it down to 15km before it explodes? Or does it explode up around 80km?

A 2.5m heatshield has about 3 times the drag of a 1.25m heatshield -- but using the bigger heatshield may cause the drop pod to flip if you have it pointing retrograde. You may want your fairing to be flared.

And in the report that you get after the explosion -- what part failed first?

 

Edited December 11, 2016 by bewing

[Jestersage]

5 hours ago, Foxster said:

Could you post a picture?

It's just a basic cylinder fairing. and a heatshield. The rover doesn't explode until the fairing goes.

 

1 hour ago, bewing said:

Whether it explodes or not depends on the mass, the speed, the Pe, which end is pointing forward, and the drag.

So, what is the exact mass of the drop pod?

Are you orbital or in an escape trajectory when you drop it? Do you mean that you are orbital with a 9Mm Ap? Do you mean that you are setting the Pe to 15km?

Are you saying that it makes it down to 15km before it explodes? Or does it explode up around 80km?

A 2.5m heatshield has about 3 times the drag of a 1.25m heatshield -- but using the bigger heatshield may cause the drop pod to flip if you have it pointing retrograde. You may want your fairing to be flared.

And in the report that you get after the explosion -- what part failed first?

I will have to check the mass -- not off the top of my head. What happened is that the fairing overheat, exploded.... then everything within exploded.

No idea about the science mumbo-jumbo. All I know is: 9000km with Cheat-Edit, deorbit by thrusters to a PE of 12k, let it ride like a cowboy. Exploded when within Eve atmosphere.

But now that you mentioned it, I think I need to make it Cone-shaped, since right now it was just a perfect cylinder.

[Palaceviking]

Spoiler

Tada!

And your periapsis is far too deep, I wouldn't even come in to duna that steeply.  you need to go shallow and bleed of speed gently,  Eve IS evil and will kill you lots!

Don't poke the bear.

Edited December 11, 2016 by Palaceviking

[Jestersage]

1 hour ago, Palaceviking said:

And your periapsis is far too deep, I wouldn't even come in to duna that steeply.  you need to go shallow and bleed of speed gently,  Eve IS evil and will kill you lots!

Don't poke the bear.

Yeah, making it cone shape does not help, since it seems like it's the fairing BASE that exploded.. Will have to figure out a way to drop the rover while it's on the flyby (hence the high AP, low PE). either that or flip it around? Not sure.

Can someone tell me what's the typical distance for Eve flyby? Just testing out the rovers before I send Jeb and Bob and Val.

[Tex_NL]

20 minutes ago, Jestersage said:

Will have to figure out a way to drop the rover while it's on the flyby (hence the high AP, low PE)

Add a small tank and some rockets. Do a retro burn and try to bleed off as much speed BEFORE hitting atmo. Then drop the retro stage. 1+1=2 It isn't that difficult.

[Jestersage]

1 hour ago, Tex_NL said:

Add a small tank and some rockets. Do a retro burn and try to bleed off as much speed BEFORE hitting atmo. Then drop the retro stage. 1+1=2 It isn't that difficult.

So assuming the flyby take place at about 9000km, and I deploy the droppods, I should probably do 3 burns -- one to lower PE, then the AP, and then a final atmospheric burn?

[Palaceviking]

If you can make orbit then just dip your peri doen to about 60 at the most, the pressure rises sharply at 50k and will eat you if your doing over about 3500ms

[foamyesque]

Could always try a maple-seed approach and build an autorotator. Be a bit tricky to get into orbit in the first place, but if your drop pods are small enough you might be able to enclose 'em in fairings.

 

EDIT:

Your approach is way steep, though. You can aerobrake but you need to stay above 85km or so, which means it'll take ages to get you to a safe orbit. A much faster approach would be to drop your periapsis to 110km or so, then execute a burn to make that your apoapsis and put your periapsis at around 70km. Eve's atmo will do the rest.

Edited December 11, 2016 by foamyesque