Falcon Heavy Demo Mission Payload Discussion

[garcianc]

The inner fairing is 4,6m  the car is 3,946 mm x 1,873 mm. The hypotenuse is 4,367. Clearance is a bit tight but on space technology should be fine.

There is no “hypotenuse” 😉
From above the car fits nicely in a circle the diameter of its length.
But your conclusion is correct.

I think what Jimmy Murdok meant by hypotenuse is the diagonal, which is more important than the length. ~20cm of clearance (~10cm at each corner) is tight for a non-standard payload sitting atop a rocket that will shake the ground a mile away.

[aero]

The inner fairing is 4,6m  the car is 3,946 mm x 1,873 mm. The hypotenuse is 4,367. Clearance is a bit tight but on space technology should be fine.

There is no “hypotenuse”
From above the car fits nicely in a circle the diameter of its length.
But your conclusion is correct.

It fits nicely with about 11 cm to spare at the corners. There could be a lot of reasons why 11 cm is not enough distance. Placing the Roadster so that its center of mass is near the horizontal center of the fairing comes to mind. Later attachment of ductwork or something else to the wall is a possible reason for needing more space. Whatever the reason I'm sure that SpaceX had a valid one for choosing the orientation that they did.

edit - cross posted with garcianc above.

[kdhilliard]

The inner fairing is 4,6m  the car is 3,946 mm x 1,873 mm. The hypotenuse is 4,367. Clearance is a bit tight but on space technology should be fine.

There is no “hypotenuse” 😉
From above the car fits nicely in a circle the diameter of its length.
But your conclusion is correct.

I think what Jimmy Murdok meant by hypotenuse is the diagonal, which is more important than the length. ~20cm of clearance (~10cm at each corner) is tight for a non-standard payload sitting atop a rocket that will shake the ground a mile away.

From 18 pages back:

The length of a Roadster IS the diagonal, or rather, the diameter.

[Comga]

The inner fairing is 4,6m  the car is 3,946 mm x 1,873 mm. The hypotenuse is 4,367. Clearance is a bit tight but on space technology should be fine.

There is no “hypotenuse” 😉
From above the car fits nicely in a circle the diameter of its length.
But your conclusion is correct.

I think what Jimmy Murdok meant by hypotenuse is the diagonal, which is more important than the length. ~20cm of clearance (~10cm at each corner) is tight for a non-standard payload sitting atop a rocket that will shake the ground a mile away.

🙄
Oh come on
Everyone here knows what a hypotenuse is.
Read my serious line
The calculation is spurious. Not wrong. Just irrelevant.
Read what aero wrote.
What adhillard quoted from my earlier post.
Do you see why “hypotenuse “ doesn’t apply?
Maybe it’s inclined to add clearance to the dynamic envelope.
Maybe it’s inclined to look cool.

[Norm38]

Lining up the center of mass makes the most sense to me.

[cppetrie]

Maybe it’s inclined to look cool.

This. Makes it look like the cars at the tops of trophies. It is itself the prize for first passenger vehicle to cross Mars’s orbit.

[Norm38]

Where is the rest of the ballast? That Roadster is only 3 Mg max.

Upper stage fuel. Curiosity was only 3.9 Mg at launch. The goal is to demo a payload into TMI, and that means delta-V.
They'll know the exact launch mass and the resulting speed. Thus they can then accurately quote any other payload a customer wants to throw to Mars. 

Now if you think the Roadster in that huge fairing looks silly, I kindly refer you to these two images (credit NASA) of Curiosity's encapsulation. First Curiosity in its capsule, then that capsule in its fairing.

So I ask, does the car still look silly as a Mars payload demonstration?

Merry Christmas!

[Hauerg]

After looking at pictures of the payload on the payload adapter I am convinced that the roadster will not detach from second stage.

(Which also makes it easier to find in the future.)

[deruch]

I assume that Elon maintains ownership of the Tesla after its deployed right?  At what point could someone decide to 'salvage' it?

I was initially thinking about a time capsule in the trunk.  But then thought maybe put some things that would appreciate in value.  So that the longer its out there the more valuable they become.  To actually encourage development of commercial technology to rendezvous and retrieve...at the very least as a 'prize'.

Maybe on Elon's death he releases a list of a few things that might encourage retrieval in the distant future?  Hopefully the vehicle itself would be left orbiting in space.

If I manage to find the Tesla Roadster in Mars orbit and retrieve it, can I keep it? @elonmusk

Yes

Tweets are not exactly legally binding, but someone's floated the idea to Elon already.

https://twitter.com/elonmusk/status/944783379022540800

The Outer Space Treaty might apply and thereby prohibit anyone from salvaging. 

[LouScheffer]

Designing that adapter was, I hope, a fun job.  Lots of engineering freedom.  Work will be seen by millions and last for billions of years.  Little "that's how it's always been done".   Can solve engineering problems by simply making it stronger, no concerns about mass, size, or need to use exotic materials.  Should look cool as well as be functional.  Easy to explain to your grandmother.  And on a project that has considerable delays, so you are not the long pole in the tent.

More seriously, it would be interesting to compare the engineering effort and build costs of this adapter (where mass and size were not constraints) to the effort required to build a typical custom adapter.   Many have claimed that relaxing the normal tight constraints would lead to much lower costs - here's a chance to see if that's true, and perhaps quantify it for a particular case.

[yg1968]

I assume that Elon maintains ownership of the Tesla after its deployed right?  At what point could someone decide to 'salvage' it?

I was initially thinking about a time capsule in the trunk.  But then thought maybe put some things that would appreciate in value.  So that the longer its out there the more valuable they become.  To actually encourage development of commercial technology to rendezvous and retrieve...at the very least as a 'prize'.

Maybe on Elon's death he releases a list of a few things that might encourage retrieval in the distant future?  Hopefully the vehicle itself would be left orbiting in space.

If I manage to find the Tesla Roadster in Mars orbit and retrieve it, can I keep it? @elonmusk

Yes

Tweets are not exactly legally binding, but someone's floated the idea to Elon already.

https://twitter.com/elonmusk/status/944783379022540800

The Outer Space Treaty might apply and thereby prohibit anyone from salvaging.

It's not salvaging if someone gives it to you.

[deruch]

Tweets are not exactly legally binding, but someone's floated the idea to Elon already.

https://twitter.com/elonmusk/status/944783379022540800

The Outer Space Treaty might apply and thereby prohibit anyone from salvaging.

It's not salvaging if someone gives it to you.

Elon isn't giving it to anyone.  He's "abandoning" it in orbit.  If someone wants to go get it, Elon's cool with that.  Which is pretty much the definition of salvage.  But unless the US Govt. is also on board with this being an ok idea, no one can legally go get it even if Elon did give it to anyone.  That's true regardless of the retriever's citizenship or where they launched from.  In fact, under OST they should be prohibited from launching to recover the roadster unless they already have USG permission to retrieve it.  And if they somehow did it on the sly, the US still has the rights to take it back on applying to the government of whatever country the car was in.  Of course, none of this is ever likely to happen, so it probably doesn't matter.  Or, by the time it could/will happen the OST will likely have been modified so the issue may be irrelevant in practice.

[envy887]

Tweets are not exactly legally binding, but someone's floated the idea to Elon already.

https://twitter.com/elonmusk/status/944783379022540800

The Outer Space Treaty might apply and thereby prohibit anyone from salvaging.

It's not salvaging if someone gives it to you.

Elon isn't giving it to anyone.  He's "abandoning" it in orbit.  If someone wants to go get it, Elon's cool with that.  Which is pretty much the definition of salvage.  But unless the US Govt. is also on board with this being an ok idea, no one can legally go get it even if Elon did give it to anyone.  That's true regardless of the retriever's citizenship or where they launched from.  In fact, under OST they should be prohibited from launching to recover the roadster unless they already have USG permission to retrieve it.  And if they somehow did it on the sly, the US still has the rights to take it back on applying to the government of whatever country the car was in.  Of course, none of this is ever likely to happen, so it probably doesn't matter.  Or, by the time it could/will happen the OST will likely have been modified so the issue may be irrelevant in practice.

Are satellites considered abandoned after they have completed their mission? I would think they remained property of the owner to perpetuity.

If SpaceX launched a mission in 5 years to go get the Roadster, I don't see why the USG would try to stop them. It should still be their property. Same if they legally transfer ownership to another party who then tries to recover it.

[meekGee]

Tweets are not exactly legally binding, but someone's floated the idea to Elon already.

https://twitter.com/elonmusk/status/944783379022540800

The Outer Space Treaty might apply and thereby prohibit anyone from salvaging.

It's not salvaging if someone gives it to you.

Elon isn't giving it to anyone.  He's "abandoning" it in orbit.  If someone wants to go get it, Elon's cool with that.  Which is pretty much the definition of salvage.  But unless the US Govt. is also on board with this being an ok idea, no one can legally go get it even if Elon did give it to anyone.  That's true regardless of the retriever's citizenship or where they launched from.  In fact, under OST they should be prohibited from launching to recover the roadster unless they already have USG permission to retrieve it.  And if they somehow did it on the sly, the US still has the rights to take it back on applying to the government of whatever country the car was in.  Of course, none of this is ever likely to happen, so it probably doesn't matter.  Or, by the time it could/will happen the OST will likely have been modified so the issue may be irrelevant in practice.

Are satellites considered abandoned after they have completed their mission? I would think they remained property of the owner to perpetuity.

If SpaceX launched a mission in 5 years to go get the Roadster, I don't see why the USG would try to stop them. It should still be their property. Same if they legally transfer ownership to another party who then tries to recover it.

  seriously, at the DMV.   Where they should also get a non-operative vehicle permit.  To save on insurance.
I mean, the law is the law.

[Grandpa to Two]

My hope is that there is a mounted camera looking through the windshield and an antenna that could relay ‘cruising through space to mars’ for us Terran observers. That would absolutely be the bomb.

[su27k]

Tweets are not exactly legally binding, but someone's floated the idea to Elon already.

https://twitter.com/elonmusk/status/944783379022540800

The Outer Space Treaty might apply and thereby prohibit anyone from salvaging.

It's not salvaging if someone gives it to you.

Elon isn't giving it to anyone.  He's "abandoning" it in orbit.  If someone wants to go get it, Elon's cool with that.  Which is pretty much the definition of salvage.  But unless the US Govt. is also on board with this being an ok idea, no one can legally go get it even if Elon did give it to anyone.  That's true regardless of the retriever's citizenship or where they launched from.  In fact, under OST they should be prohibited from launching to recover the roadster unless they already have USG permission to retrieve it.  And if they somehow did it on the sly, the US still has the rights to take it back on applying to the government of whatever country the car was in.  Of course, none of this is ever likely to happen, so it probably doesn't matter.  Or, by the time it could/will happen the OST will likely have been modified so the issue may be irrelevant in practice.

Are satellites considered abandoned after they have completed their mission? I would think they remained property of the owner to perpetuity.

If SpaceX launched a mission in 5 years to go get the Roadster, I don't see why the USG would try to stop them. It should still be their property. Same if they legally transfer ownership to another party who then tries to recover it.

Since the US is the launching country, OST Article VII and VIII doesn't apply if a US citizen/company wants to salvage the car, the savager still need a FAA launch license though. Things get murky and complicated if a foreign entity wants to salvage the car.