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Comment by _Microft | Hacker News Reader

We have never seen the actual release of the Starlink satellites.

During every launch the hosts on the stream state that an unfortunate unexpected loss of signal happened but since the stream is stable before and after payload separation, this would be surprising. One might have thought that the vehicle was just at an unfortunate point in the trajectory where no connection was actually possible but today's payload separation event was far earlier and the video cut off anyways.

It is a bit surprising since the mechanism does not seem that sophisticated.

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I thought this was because video was provided by line of sight antennas and as Starlink satellites are released the 2nd stage flips end over end while releasing them thus breaking the line of sight.

you mean the seconds before this?:

https://youtu.be/vFTg3-40Mfg?t=745

https://www.msn.com/en-us/news/technology/spacex-releases-60...

or for this launch?

Putting Starlink launches on different screens and letting them run synchronized from the time that the video cuts off: the confirmation of tension rod release and payload separation and the video coming back happens almost at the same time.

Today: https://youtu.be/8xeX62mLcf8?t=1489

January, 29th: https://youtu.be/1KmBDCiL7MU?t=4414

January, 6th: https://youtu.be/HwyXo6T7jC4?t=4390

November, 11th: https://youtu.be/pIDuv0Ta0XQ?t=4549

May, 25th: https://youtu.be/riBaVeDTEWI?t=4579

From my understanding, the second stage starts spinning just before the release of Starlink satellites to give the stack the momentum necessary for the clean separation. This could explain the loss of camera feed. Internal SpaceX telemetry is likely being transmitted over a separate channel and remains uninterruptible.

Yes, they spin it to disperse the satellites. The loss of video depending on the rotation is a good idea and indeed it looks like the video is failing frequently before the separation event as well. See https://youtu.be/HwyXo6T7jC4?t=4286

very interesting. I don't believe the rotation to be the cause though, the angle towards the ground doesn't change much.

I thought maybe it's the shock from the release, but I think the release happens quite a bit after the video cuts off (judging from how close the satellites still are when it comes back)

Vibration. The deployment probably disturbs the telemetry connection for a second. The same thing used to happen for landings. The camera would always cut out right as the booster reached the barge because the vibration interrupted the telemetry connection temporarily.

Like we never saw the actual landing of the F9 on a droneship until very recently. I remember being very surprised when the camera suddenly DIDN'T stop working and you could actually see the F9 actually land.

Some of the early landings have been shown from drones, NASA aircraft cameras (hello Canberra!) or from a recording from the rocket itself.

On land or on a drone ship?

I thought I've seen pretty much all of the landings, but can't recall a drone ship landing shown from an air plane camera.

Especially with all the exploding rockets in the early days of landings.

Do you have a link to one such landing, would be really interesting to see.

The first droneship landing after launching Dragon with cargo to the ISS (CRS-8) was filmed from the air: https://www.youtube.com/watch?v=sYmQQn_ZSys

Mission description is at https://en.wikipedia.org/wiki/SpaceX_CRS-8

Maybe there is some secret sauce they don't want known.

... which is fine and understandable, but they should really stop with this "oh, we lost a feed" bullshit. It's obnoxious.

How many other launch providers before SpaceX even had feeds of their launches or their payload separations?

People really should stop complaining about the really cool thing SpaceX does, but not perfectly.

Doing very cool stuff is not a reason enough to be disrespectful towards your audience.

During one of the first booster landing attempts a presenter lady was staring at her monitor, saw the booster crash and then proceeded to blatantly lie that the feed was lost... while the jumbotron behind her back was showing the whole thing in real-time and the audio picking up the crowd in SpaceX going "Oooooh".

Then, there are their inane explanations that they keep losing the feed from the landing platform because the sea is rippled. The heck. If you are going to lie, come up with something a bit more plausible. A plasma ball interference from the plume or something.

Better yet, just say that we are going to delay the feed by 10 seconds and we may withhold any part of it as we wish. Everyone would be perfectly fine with that. It's their feed and it's awesome when they share anything at all. Just don't BS. There's literally no need to do that.

Pretty much all of them? Certainly, I remember watching realplayer streams of the first-generation Iridium satellites being launched, way back in the late 1990s.

I've been watching SpX stuff for so many years now, I am pretty sure they would just say so if that was the case.

Delta = 0

Alright guys. The competition will never figure out they need to stop before the rocket reaches the ground!

Right the tension rod release mechanism isn't shown. The tension rods are chucked away as space junk which the announcer probably doesn't want to talk about. Also agree it's kind of secret sauce. Much simpler than oneweb's corncob dispenser.

These are lower orbits so any space junk released is eventually going to burn up. Not sure how long it'll take... years I think, but not too long.

Perhaps it is related to USML 1.121[1] Category XV.4(a)?

[1] https://www.law.cornell.edu/cfr/text/22/121.1

Are you claiming these sats dont exist? Or simply that a for profit company didn't record for it so noncustomers could watch it for free?

> It is a bit surprising since the mechanism does not seem that sophisticated.

I am hinting there at a clever solution that they do not want to show (or a solution that they must not show because of regulations).

I'm guessing it might be censored for national security reasons. The same mechanism that successfully deploys 60 satellites could probably also successfully deploy 60 warheads. Or 60 nefarious spy satellites.

It's a good question about something that is probably not a coincidence! But immediately moving to speculating about a conspiracy theory seems like hiding a good question with a fake answer.

It seems better to keep it unanswered and remain curious.

"Conspiracy theory" is an exaggeration. Lots of things rocketry related are covered by ITAR and are not allowed (by law) to be shown to non-green-card holders. SpaceX is pretty careful to comply with ITAR restrictions. It would not surprise me in the slightest if the US government had decided that satellite deployment mechanisms were one of those things covered, or if SpaceX's legal department decided that they weren't sure they weren't covered.

If that were true, they would simply say as much. What possible advantage would there be to offer a bullshit reason?

A far more likely reason is that it's technically hard, and/or not a priority.

I tend to agree, but that doesn't mean keeping quiet about ITAR is "conspiracy theory" level of ridiculousness.

Possible advantages could be avoiding looking like they are putting pressure on the US government to change it, avoid getting into debates about whether or not ITAR prohibits it, avoiding looking like they are a workplace that is heavily bogged down by security clearance issues, etc.

Yeah, I totally have to agree.

They have repeatedly cut streams and stated they aren't allowed to show the payload deploying.

I don't think it's intellectually honest to label something as a conspiracy theory and brush it aside without discussion.

I said "conspiracy theory" when I should have more accurately said "to keep a secret." But it's still just a bit of speculation; we don't know that there is a secret.

Does "Unfounded speculation about an organized effort to deliberately mislead the public" do more justice to the subject?

They say it's a simple tension mechanism, nothing fancy. The attachment of the satellite stack is not even within the camera's FoV.

I'm guessing it's just a vibration issue.

Is a deployment bus really that complicated? It's what, a girder with a couple of solenoids or explosive bolts?

Given the nose cone fairings cost $6 million [0], I don’t think anything in space tech can be non-complicated and useful at the same time.

[0] If it were literally any other company in space, I would accuse them of porkbarrelling. SpaceX looks like it is genuinely concerned with cost, so I don’t think that’s happening in this case.

If I remember correctly, SpX is one of the few (only) who doesn't use explosives for their fairing separation or sat releases. Just some springs, because "they can be tested before the flight".

And even though very reliable, explosive bolts do fail, sometimes spectacularly. Just a few years ago an Indian PSLV fairing separation failed, yet released the sattelite inside the closed fairing, which did reach orbit. As it could not get out, this was a failed launch & IIRC the failed fairing separation mechanism was pyrotechnic.

>The same mechanism that successfully deploys 60 satellites could probably also successfully deploy 60 warheads

We've had missiles that could do that since 1970. They're called MIRVs.

https://en.wikipedia.org/wiki/Multiple_independently_targeta...

MIRVs are almost certainly covered by ITAR, so the fact that they exist doesn't really change anything...

Of all the different parts a ICBM is made of, I doubt that the warhead release mechanism is the most difficult.

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