Author Topic: SpaceX FH : Falcon Heavy Demo : Feb 6, 2018 : Discussion Thread 2  (Read 337254 times)

Offline RocketLover0119

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I think june.

when is the next FH flight scheduled?
"The Falcon has landed"

Offline Zipi

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From this video you can see a glimpse about the center core splashing down near OCISLY after 1:11:


Broken man-made things can be fixed (if you find the pieces).

Online Comga

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when is the next FH flight scheduled?

See the Manifest thread
It says NET June for STP-2
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

Offline OnWithTheShow

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Yes, the video clearly shows the stage coming in at an angle and overshooting the ASDS. For those who missed it, the great "overshoot vs. undershoot" debate started here:

https://forum.nasaspaceflight.com/index.php?topic=44778.msg1788585#msg1788585

...and lasted several pages, so is worth revisiting in light of the new video. Hopefully all debaters will view the video and some will see the error of their ways.  Meanwhile, you may bask in the knowledge that you were indeed correct.  ;D

stirring

But what if RTLS cores undershoot and ballistic ASDS cores overshoot?

/stirring

Offline Lar

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Don't be a pot stirrer!
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Offline Kabloona

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Yes, the video clearly shows the stage coming in at an angle and overshooting the ASDS. For those who missed it, the great "overshoot vs. undershoot" debate started here:

https://forum.nasaspaceflight.com/index.php?topic=44778.msg1788585#msg1788585

...and lasted several pages, so is worth revisiting in light of the new video. Hopefully all debaters will view the video and some will see the error of their ways.  Meanwhile, you may bask in the knowledge that you were indeed correct.  ;D

stirring

But what if RTLS cores undershoot and ballistic ASDS cores overshoot?

/stirring

It being a slow day, I'll take the bait and suggest it makes no sense to have two different terminal guidance algorithms.

SpaceX was required by the Range to demonstrate landing accuracy on the ASDS before they were allowed to attempt RTLS landings, and I find it unlikely that the Range would approve an RTLS attempt using a different algorithm than was demo'd on the ASDS.

I also find it unlikely that SpaceX would introduce the unnecessary complexity of using two different terminal guidance algorithms.

Now, are we allowed to hope one of those RTLS cores runs out of TEA/TEB, or would that be wrong?  ;)

Offline biosehnsucht

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Re: Re: SpaceX FH : Falcon Heavy Demo : Feb. 6, 2018 : Updates
« Reply #1466 on: 03/12/2018 09:00 PM »
Legs not deploying likely not "an additional failure" but merely a result of going too damn fast and thus either they failed to deploy because that was based on some kind of timing as a function of elapsed mission time, or because there was so little time between the deployment altitude / time to surface that they never got a chance to move before splashing.

Offline Jcc

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I guess this footage should end the debate of whether or not a stage will overshoot or undershoot itís landing spot if the engines fail to light for the landing burn. (But who am I kidding, of course it wonít)

You actually convinced me half way through but was having too much fun to stop.

Offline SkyRate

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Re: Re: SpaceX FH : Falcon Heavy Demo : Feb. 6, 2018 : Updates
« Reply #1468 on: 04/07/2018 12:52 AM »
Even if there is no speed sanity check in the leg extension trigger and it considers just altitude or time-to-zero-altitude, I suspect that the actuators were just not strong enough to push the legs down.
If, say,  the speed was 3 times higher than normal then the aerodynamic forces on the legs were 9 times higher.
You just don't overdesign things to that degree on a rocket.

Offline NGCHunter

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Here are some stacked images I made from the Falcon Heavy launch using my telescopic tracking footage.  I stacked about 5~6 consecutive frames.  In the case of the boostback image, I had to layer two stacks; one aligned on the boosters, the other aligned on the core stage due to the differential motion even over 5 frames.

http://h.dropcanvas.com/t7z6r/falconheavy6stackedframes17x20.jpg

http://h.dropcanvas.com/t7z6r/fhboostbacklayering3final.jpg

I think it's the first time I've done image stacking for launch photos, but it came out pretty well.
« Last Edit: 04/10/2018 07:15 PM by NGCHunter »

Offline Space Ghost 1962

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Very good work. Not easy to get such high detail and saturated color imagery. Or the detail on the booster's flip and ignition. Can even notice some TO hints in the plumes.

Thank you for sharing your work.

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