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9 minutes ago, cubinator said:

As Falcon 9 reenters Earth's atmosphere, doesn't it experience a sort of second Max-Q? At what altitude and speed are the forces the greatest during descent?

For FORMOSAT-5 i looked quickly. At an altitude of 25,1km the first stage was at 3235km/h, after that point it only decelerates. So there would need to be the highest forces i think:wink:

 

(If my english is too bad, I'm sorry. In Germany I usually don't speak english:P)

Edited by Nightfury
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1 hour ago, tater said:

In answering a tweet about ITS landing on a mount (no legs), he said that the tolerance would probably be about 2m.

Interesting, that's the first I've seen official information on booster separation velocity (although you can slow-mo through the video and get the data in km/h).  Expect much scarier velocities on Falcon Heavy (success of the mission wouldn't be nearly the surprise that spacex is warning people of, landing the center stage is far beyond any landing they've pulled off (because the upper stage needs so much more of a push, and the center stage is the only thing that can push it).

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2 hours ago, Nightfury said:

For FORMOSAT-5 i looked quickly. At an altitude of 25,1km the first stage was at 3235km/h, after that point it only decelerates. So there would need to be the highest forces i think:wink:

 

(If my english is too bad, I'm sorry. In Germany I usually don't speak english:P)

At that point you only have 1g of "deceleration" from aerodynamics, it gets way worse in the flight. One way to find out would be to go frame per frame throught the video and look for the biggest change in velocity.

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10 minutes ago, Elthy said:

At that point you only have 1g of "deceleration" from aerodynamics, it gets way worse in the flight. One way to find out would be to go frame per frame throught the video and look for the biggest change in velocity.

Ouh, right...could have know this from my landings in KSP:/ 

(The air is getting thicker and thicker, which causes more drag)

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30 minutes ago, Cunjo Carl said:

Sorry if it's common knowledge, but have there been any updates on the Raptor engine since its scale test last year?

Image result for raptor engine test baby raptor packs a punch

Composite of two images (the second one only for reference). That, as far as we know is the test stand for "Baby Raptor" at McGregor. As you can see, it packs quite a punch judging by those grass burn marks...

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1 minute ago, Ultimate Steve said:

Composite of two images (the second one only for reference). That, as far as we know is the test stand for "Baby Raptor" at McGregor. As you can see, it packs quite a punch judging by those grass burn marks...

That's.... SO COOL!!

 

I need one for my weeds.

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2 hours ago, Cunjo Carl said:

That's.... SO COOL!!

I need one for my weeds.

Heh - you beat me to it. :) 

"Well - that'll keep the weeds down' is the first thing I thought too.

 

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On 24/08/2017 at 8:26 PM, tater said:

As long as the difference is there, that's all that matters, so you could over pressurize the suit as well, and not bother with a vac chamber.

Static fire in 8 days:

 

I mean there may be volatility issues with sealants or materials or such that you'd only discover in a true vacuum test. For pressure vessel integrity I completely agree that 3bar should be good enough.

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9 hours ago, Ultimate Steve said:

Composite of two images (the second one only for reference). That, as far as we know is the test stand for "Baby Raptor" at McGregor. As you can see, it packs quite a punch judging by those grass burn marks...

Yikes.  Just how often is central Texas under a burn ban, or does Texas simply not dare violate a property owner's right to create wildfires?  Maybe the brush is thin enough that those roads are enough of a firebreak, but I suspect that central Texas wind can move sparks a good long way.  Maybe the Californians running spacex know a lot more about wildfires than me (I'm on the East Coast, they're unheard of here) and understand why it isn't a problem (or at least wasn't when the fire in the picture happened).

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Anyone else have any information/speculation on the readiness of SLC-40? OTV-5 is listed as launching from LC-39A on SpaceflightNow and this appears to be the last Florida launch from that pad until Falcon Heavy. Also, is it too early to start the OTV-5 hypetrain?

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On 8/25/2017 at 9:33 AM, cubinator said:

As Falcon 9 reenters Earth's atmosphere, doesn't it experience a sort of second Max-Q? At what altitude and speed are the forces the greatest during descent?

That's partly the reason for an entry burn; to slow the craft down enough so Max Q isn't much of a problem.

Edited by Grand Ship Builder
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