SpaceX F9 : Starlink 5 (v1.0 L4) : Feb. 17, 2020 : Master Thread

[Vettedrmr]

An engine / TVC problem would almost certainly prevent a soft, and therefore upright, landing.  The only system that comes in to play that late in the sequence is the legs -- maybe one didn't fully deploy or lock a la Jason 3.

Leg deployment is my favorite theory, but I would have thought EM would have sent that info out quickly if that were the case.  So still just a mystery.

[brettreds2k]

It is unusual for Elon to be this quiet about the cause of the failed landing or the status of the stage (Meaning if its being brought back being pulled by a tug) Usually about an hour after a failed landing he posts why it failed.

[CJ]

It is unusual for Elon to be this quiet about the cause of the failed landing or the status of the stage (Meaning if its being brought back being pulled by a tug) Usually about an hour after a failed landing he posts why it failed.

It's definitely unusual. It makes me wonder if there's a reason for the silence. My guess is either ITAR, or, they just aren't sure what happened yet.

[Comga]

Just after the entry burn, around T+00:07:28, someone says "Stage 1 LOS expected". What does LOS mean in this context?
<snip>
It could also mean "Loss Of Signal" referring to the downlink though, or lots of other things.

Your final guess is correct.  LOS in this context = Loss Of Signal

Welcome aboard!

Thanks!
So the loss of the downlink signal at that point wasn't unexpected, which could be for a number of different reasons

The callout over the network of "LOS (location) expected" is heard several times during each launch.
It means that "Loss of Signal" has occurred for one of several ground stations, like Bermuda for northerly launches from the Cape, as expected given that point on the trajectory.  It acknowledges that the point has been reached where the geometry or distance precludes communicating with that particular ground station. 

It may be that a different callout signals the blackout of communications during reentry due to the plasma generated off the heat shield.
This does not occur for the first stage.

[capoman]

It is unusual for Elon to be this quiet about the cause of the failed landing or the status of the stage (Meaning if its being brought back being pulled by a tug) Usually about an hour after a failed landing he posts why it failed.

It's definitely unusual. It makes me wonder if there's a reason for the silence. My guess is either ITAR, or, they just aren't sure what happened yet.

I doubt it's ITAR. SpaceX tends to keep quiet during investigations. I suspect they don't have a clear cause and are investigating. It's a good thing to keep quiet until you have some facts.

[Lars-J]

It is unusual for Elon to be this quiet about the cause of the failed landing or the status of the stage (Meaning if its being brought back being pulled by a tug) Usually about an hour after a failed landing he posts why it failed.

It's definitely unusual. It makes me wonder if there's a reason for the silence. My guess is either ITAR, or, they just aren't sure what happened yet.

C’mon folks. Just because we sometimes get fast tweets from CEO, Let’s not act like spoiled kids who need instant gratification when those tweets don’t materialize. (Or go into conspiracy theories as sometimes happens) He is under no obligation to do any of it.

[jcm]

No TLEs for the Starlinks yet, but the second stage has been cataloged as 2020-012BS in a 191 x 374 km x 53.0 deg orbit

[CJ]

It is unusual for Elon to be this quiet about the cause of the failed landing or the status of the stage (Meaning if its being brought back being pulled by a tug) Usually about an hour after a failed landing he posts why it failed.

It's definitely unusual. It makes me wonder if there's a reason for the silence. My guess is either ITAR, or, they just aren't sure what happened yet.

I doubt it's ITAR. SpaceX tends to keep quiet during investigations. I suspect they don't have a clear cause and are investigating. It's a good thing to keep quiet until you have some facts.

I very much concur that it's best to keep quiet until they have facts. SpaceX has been very good, historically, about not saying things until they are pretty sure. That's what makes me think they are investigating, as I suspect (based on the past) that if they knew for certain what happened, they would have probably said so by now.

Or, it could be related to something proprietary related to how F9 lands, which for perfectly understandable reasons they'd prefer to not talk about. 

If I had to bet, (and I'm glad I don't, because I'd probably lose) I'd say a hydraulic leak from the grid fin system. My reasoning is admittedly weak; the arched piece seen coming away during the flight seemed flexible, not like ice. So, I'm guessing hydraulic fluid. The F9 could have ended up losing grid fin control late in the descent, and thus either diverted, or, simply didn't get close enough to be able land.

[harrystranger]

Some incredible footage of the launch!

[JamesH65]

It is unusual for Elon to be this quiet about the cause of the failed landing or the status of the stage (Meaning if its being brought back being pulled by a tug) Usually about an hour after a failed landing he posts why it failed.

It's definitely unusual. It makes me wonder if there's a reason for the silence. My guess is either ITAR, or, they just aren't sure what happened yet.

I doubt it's ITAR. SpaceX tends to keep quiet during investigations. I suspect they don't have a clear cause and are investigating. It's a good thing to keep quiet until you have some facts.

I very much concur that it's best to keep quiet until they have facts. SpaceX has been very good, historically, about not saying things until they are pretty sure. That's what makes me think they are investigating, as I suspect (based on the past) that if they knew for certain what happened, they would have probably said so by now.

Or, it could be related to something proprietary related to how F9 lands, which for perfectly understandable reasons they'd prefer to not talk about. 

If I had to bet, (and I'm glad I don't, because I'd probably lose) I'd say a hydraulic leak from the grid fin system. My reasoning is admittedly weak; the arched piece seen coming away during the flight seemed flexible, not like ice. So, I'm guessing hydraulic fluid. The F9 could have ended up losing grid fin control late in the descent, and thus either diverted, or, simply didn't get close enough to be able land.

It landed next to the drone ship, close enough that the splash spray was visible in the camera view. Since the grid fins do not supply an awful of guidance at landing speed (its mostly RCS at low speed), most of their work is done at higher altitudes,  so to get that close to the drone ship must imply that the grid fins worked correctly most of the way down.

[FutureSpaceTourist]

https://twitter.com/spacexfleet/status/1230490173428899842

Good morning! OCISLY is set for an arrival at Port Canaveral later today, possibly in as little as 3 hours from now but they may wait for GO Quest who is some 7 hours away.

Ms Tree and Ms. Chief are about 6 hours away.

tl;dr... It's going to be a busy day of arrivals!

Still unknown what, if anything, they are bringing anything back (fairings and/or parts of booster)

[FutureSpaceTourist]

https://twitter.com/julia_bergeron/status/1230561875919654912

First look at Tug Hawk and OCISLY slowing making their way towards Port Canaveral. With #B1056 taking a turn into the Atlantic during landing they are coming back empty handed. Go Quest, Ms. Chief and Ms. Tree will be inbound later today. #SpaceXFleet

[Prettz]

On a normal booster recovery mission they don't really have any equipment on any of the ships out there to pull booster parts out of the water, do they?

[FutureSpaceTourist]

https://twitter.com/johnkrausphotos/status/1230571933005164544

SpaceX’s Of Course I Still Love You droneship has returned to Port Canaveral following Monday’s Starlink mission, during which the Falcon 9 landed softly on the water nearby the droneship.

Per @SpaceXFleet: This is the first time OCISLY has returned empty-handed since June 2019.

[FutureSpaceTourist]

https://twitter.com/julia_bergeron/status/1230598643377463326

GO Ms. Chief leads the charge into Port Canaveral for the #SpaceXFleet with the Coast Guard Confidence coming in ahead of them. Welcome home sisters, welcome home!

https://twitter.com/julia_bergeron/status/1230599747314028544

Go Ms. Chief and GO Ms. Tree are majestic to watch come into port.
I can't even express how beautiful this was to see. #SpaceXFleet

twitter.com/julia_bergeron/status/1230601340545568768

That is a fairing half on GO Ms. Chief and it is kinda broken 😔 But welcome home happy crew! #SpaceXFleet pic.twitter.com/78G1i9OoUs

Edit to add:

https://twitter.com/julia_bergeron/status/1230601901584068608

GO Ms. Tree did not get much better of a catch. Broken fairing half for them as well. Welcome home happy crew! #SpaceXFleet

Close-up

https://twitter.com/julia_bergeron/status/1230603880301518848

This appears to have been a rough mission all around. Fairing hauls from GO Ms. Chief and GO Ms. Tree respectively. #SpaceXFleet #Starlink

[FutureSpaceTourist]

https://twitter.com/gregscott_photo/status/1230608226158338050

Go Ms Tree & Ms Chief just pulled back into port about 4:20 pm this afternoon. Both were carrying fairings but both fairings were heavily damaged & broken apart. Unknown if this happened upon impact or damaged while recovery. #SpaceX #NASA #space #SpaceXFleet

Edit to add:

https://twitter.com/kyle_m_photo/status/1230706329485901824

Better shots of GO Ms. Tree's fairing half.  #SpaceXFleet #SpaceX

https://twitter.com/kyle_m_photo/status/1230703827956797442

Better shots of GO Ms. Chief's fairing half.  #SpaceXFleet #SpaceX

[LouScheffer]

I doubt it's ITAR. SpaceX tends to keep quiet during investigations. I suspect they don't have a clear cause and are investigating. It's a good thing to keep quiet until you have some facts.

Maybe it's something really embarrassing, such as leaving a pin out of one of the legs, then having two inspectors still sign off on it.  Something like that would put their whole safety culture and QA conscientiousness in question.

[harrystranger]

Even more incredible footage of the launch, and that sound!

[edkyle99]

I doubt it's ITAR. SpaceX tends to keep quiet during investigations. I suspect they don't have a clear cause and are investigating. It's a good thing to keep quiet until you have some facts.

Maybe it's something really embarrassing, such as leaving a pin out of one of the legs, then having two inspectors still sign off on it.  Something like that would put their whole safety culture and QA conscientiousness in question.

An oddly specific speculation.  Basis?

 - Ed Kyle

[oiorionsbelt]

I doubt it's ITAR. SpaceX tends to keep quiet during investigations. I suspect they don't have a clear cause and are investigating. It's a good thing to keep quiet until you have some facts.

Maybe it's something really embarrassing, such as leaving a pin out of one of the legs, then having two inspectors still sign off on it.  Something like that would put their whole safety culture and QA conscientiousness in question.

An oddly specific speculation.  Basis?

 - Ed Kyle

You may have missed the [sarc] font