SpaceX Falcon 9 / Dragon 2 : SpX-DM1 : March 2, 2019 : DISCUSSION

[Lars-J]

Strongback should start to retract soon.

Nope!

It looks like they did the static fire without retracting the strongback

It looked like it was retracted. It doesn't retract much (5 degrees?), and it is even less apparent from the stream angle. But perhaps my eyes are deceiving me.

[Craftyatom]

Strongback should start to retract soon.

Nope!

It looks like they did the static fire without retracting the strongback

I believe they probably retracted it one and a half degrees, like they do for most launches prior to liftoff.  It's hard to tell from this distance/at this angle.

[ChrisC]

Static fire and then, Crew Access Arm back...

I watched the Florida stream for a little while after the static fire and didn't see the CAA move back.  Then they ended the stream when I wasn't looking.  Were these screenshots from the FT stream, or SpaceFlightNow, or other?  And more importantly, approximately what time did the CAA go back, and can you characterize how quickly it moved?  The move away from the capsule during the countdown was apparently rather quick, per reports here earlier.

[Alexphysics]

Venting!

So SpaceX did NOT retract the strongback before LOX loading.
Interesting

Why would they even need to retract the strongback for that? The rocket needs to be almost fully fueled and the tanks must be at almost flight pressures for the strongback to be retracted, they have explained that on many of their webcasts.

[Alexphysics]

Strongback should start to retract soon.

Nope!

It looks like they did the static fire without retracting the strongback

The strongback retracted at T-4min like usual

[Joffan]

So SpaceX did NOT retract the strongback before LOX loading.
Interesting

Why would they even need to retract the strongback for that? The rocket needs to be almost fully fueled and the tanks must be at almost flight pressures for the strongback to be retracted, they have explained that on many of their webcasts.

"Test Like You Fly" is the simple answer to "why would they retract the strongback?". In the same way the static fire is conducted fully fueled and at flight pressure; the fuel is not necessary for a 3-second burn and I doubt the full pressure is either.

[whitelancer64]

So SpaceX did NOT retract the strongback before LOX loading.
Interesting

Why would they even need to retract the strongback for that? The rocket needs to be almost fully fueled and the tanks must be at almost flight pressures for the strongback to be retracted, they have explained that on many of their webcasts.

"Test Like You Fly" is the simple answer to "why would they retract the strongback?". In the same way the static fire is conducted fully fueled and at flight pressure; the fuel is not necessary for a 3-second burn and I doubt the full pressure is either.

For a launch, the strongback isn't retracted until T-4 min, so they did "test like they fly."

Static fires are done with full fuel loads and at flight pressures. It is a complete wet dress rehearsal for launch, the only difference is that for a launch they release the hold-down clamps on the rocket.

[Alexphysics]

So SpaceX did NOT retract the strongback before LOX loading.
Interesting

Why would they even need to retract the strongback for that? The rocket needs to be almost fully fueled and the tanks must be at almost flight pressures for the strongback to be retracted, they have explained that on many of their webcasts.

"Test Like You Fly" is the simple answer to "why would they retract the strongback?". In the same way the static fire is conducted fully fueled and at flight pressure; the fuel is not necessary for a 3-second burn and I doubt the full pressure is either.

I don't think you understood my comment properly. The other user was talking about a retraction BEFORE even fueling began which has never happened and it's not what it is going to happen. I was talking about that and not about the actual retraction that happens at T-4min. They ALWAYS load the vehicle entirely for the static fires and have the tanks at flight pressure. This static fire was like any other one in terms of that, nothing really special and on the Florida Today livestream you could even see the upper clamps opening and then the strongback retracting.

[Joffan]

I don't think you understood my comment properly. The other user was talking about a retraction BEFORE even fueling began which has never happened and it's not what it is going to happen. I was talking about that and not about the actual retraction that happens at T-4min. They ALWAYS load the vehicle entirely for the static fires and have the tanks at flight pressure. This static fire was like any other one in terms of that, nothing really special and on the Florida Today livestream you could even see the upper clamps opening and then the strongback retracting.

Yes, I misunderstood your comment. We are in complete agreement on the process.

[Comga]

So SpaceX did NOT retract the strongback before LOX loading.
Interesting


(other posts skipped)

I don't think you understood my comment properly. The other user was talking about a retraction BEFORE even fueling began which has never happened and it's not what it is going to happen. I was talking about that and not about the actual retraction that happens at T-4min. They ALWAYS load the vehicle entirely for the static fires and have the tanks at flight pressure. This static fire was like any other one in terms of that, nothing really special and on the Florida Today livestream you could even see the upper clamps opening and then the strongback retracting.

Correct
As "the other user" my question was about the strongback during most of fueling.
SpaceX is convincing NASA that it is safe to fuel Falcon while the astronauts are on board.
It is the common assumption that one reason is that Crew Dragon has the Launch Abort System on standby during fueling.
SpaceX leans back the strongback at T-4:00 for all satellite and Cargo Dragon launches.
But satellite and Cargo Dragon launches don't have LAS, so that history is not 100% representative.
before the strongback retracts, if the LAS was activated, its top would still be right there close to or touching the capsule.
All the umbilical retractors would be at angles other than what they are designed for
It would seem to be an additional hazard, one that may not have been present in the Ground Abort test.
But it seems SpaceX and NASA are OK with this.

[eeergo]

Moving it here since I mistakenly posted it as a comment in the updates thread:


https://twitter.com/SpaceX/status/1088633393149968384


The shutdown does sound "bangy"... I wonder if it's a real feature, or just the microphone's gain passing from being saturated by the high-power roar, adjusting its gain in the descending slope of decreasing sound power level, and making it appear as if there was a sudden loud burst.

[TJL]

So, was this the first SpaceX static test fire with spacecraft since Amos-6?

[rockets4life97]

So, was this the first SpaceX static test fire with spacecraft since Amos-6?

By my recollection (and I follow SpaceX closely), the answer is yes.

[topo334]

Just watched the vid. the mic was definitely overwhelmed! (audio engineer)

[strawwalker]

With a launch on Feb 23 the current Dragon 2 comms STA will expire before the mission ends. 0915-EX-ST-2018 is valid through March 1. I guess we should expect to see a new request in the coming days.

[spacebleachers]

Not that it necessarily means anything, but the NASA Administrator indicated they were still going to launch Demo-1 in February. I'm sure he isn't in the know on the very latest, but he did end today's town hall with that statement being one of things coming in the near future.

[Comga]

https://spaceflightnow.com/launch-schedule/

NET Feb. 23 Falcon 9 • Crew Dragon Demo 1
Launch time: 1033 GMT (5:33 a.m. EST)

Sunrise time Feb 23 at the Cape would be 6:53 AM EST.
Sunlight would be a few hundred kilometers AGL, so it might not light up the plumes around staging, which will be pretty far offshore due to the flattened trajectory.
Might not be a visually striking display.
And every day of additional delay pushes the launch deeper into the night.

[gongora]

With a launch on Feb 23 the current Dragon 2 comms STA will expire before the mission ends. 0915-EX-ST-2018 is valid through March 1. I guess we should expect to see a new request in the coming days.

0068-EX-ST-2019  NET March 2

[Comga]

Not that it necessarily means anything, but the NASA Administrator indicated they were still going to launch Demo-1 in February. I'm sure he isn't in the know on the very latest, but he did end today's town hall with that statement being one of things coming in the near future.

For those of you who want to see it, it's around 37:00 into the Administrator's speech to Headquarters which can be seen here.
 

[mainmind]

Eric Ralph claims on twitter that DM-1 is now NET March, but can't link source. Don't know if this qualifies for the Updates thread, so Mod can delete as seen fit.

Source is an employee familiar with the matter.

(This is Eric).

Public confirmation is here for a NET 2 March launch:
https://fcc.report/ELS/Space-Exploration-Technologies-Corp/0068-EX-ST-2019?fbclid=IwAR3W9pOtBy9hrusZ1T7gXoMWzEDUQ2sU3LaDR9ojHGEFWppXLEjNWd6PbAk