Author Topic: SpaceX Falcon 9: To Static Fire or not to Static Fire; that is the question  (Read 54531 times)

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
OK, it's that time again...Static Fire or no Static Fire for the Falcon 9 launching Starlink v1.0 Flight 10?
It is the first time a first stage will be launched for a sixth time.

EDIT: See L2.
Static Fire at 6:00 am EDT, Monday, August 17.
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline dondar

  • Full Member
  • ****
  • Posts: 400
  • the Netherlands
  • Liked: 288
  • Likes Given: 226
All these arguments for static fires, and I don't see an answer to the one thing that confuses me. Why is it impossible for all the factors they look at to be automatically evaluated by computer in the second between ignition and liftoff? To paraphrase Data, a second is a very long time for a computer.
they do it actually (Shuttle, Delta IV, Electron all had at least one such abort). That is why all other companies don't do static fire.
I believe the main reason of SpaceX static fires is rehearsal. Banal training and getting into "the mood".
The static fire is not that expensive (all other companies do pref-light testing anyway and time-money costs are of a similar value).

To TL/DR this and many/many other questions: by all accounts SpaceX is designed and managed by engineer fanatics with engineer fanatics in mind. Everything they do fit this paradigm very tightly.

IMHO with respect to Static Firing, in systems there is something called "emergent behavior" where the sum is greater than the parts. One needs to run the system as a system, fully to exercise these behaviors, and the interesting part is that emergent behaviors are not all good, failures can be "emergent" as well.  Others have cited vibration and I am sure they look at the mechanical spectrum, but also a critical issue that can only be evaluated during a static fire is acoustic signatures.  SpaceX will have very good data on the acoustic signature of a good rocket, and any deviation from that signature will signify a potential problem. The sound turns out to be one of the best predictors of good health and one of the earliest indicators of a pending failure.  Certainly, with Raptor's we heard bad things sometimes before one sees bad things.   So getting an acoustic signature would be one of the things I as a systems engineer would be looking for.
Pfff.
All modern systems Falcon included can stop launching procedure after engine start-up and before take-off. The platforms I've mentioned had such aborts (the information is readily available online).
 They don't test "acoustic signature" per se.
More of it the important acoustic signatures happen only in flight (that is why they monitor max Q point). During start up sequence the acoustic situation is hap-hazardous and there is nothing to measure against.
 It was the case for small rockets, it should be even worse for these giants screened by walls of falling water.

They follow launching check-lists and enjoy extra possibility to do everything right without pressure of the launching "book-keeping", they get a chance to practice and to say easier hearten "Go" for launch (which used to be a big deal and apparently is a big deal in SpaceX).
I remind that re-usability is amazing gift which gave these engineers rare opportunity to see their rockets after flight and translate their "assumptions" into "knowledge". Static fire is another "smaller gift" translating "anticipation" into "expectation".

This explanation is given by the test engineer who did his rounds from 60 till 80s.

While Musk will be the "chief engineer" they will keep doing normal engineering thingies. "Test as you fly", "practice regularly" etc.etc. etc. and the rest will or envy or bitch around...

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
FYI re: SAOCOM 1B Static Fire:
Also, a reminder about the upcoming Static Fire--if the information is still correct, then Static Fire will be on August 22.
I followed the story on the web: https://bit.ly/EquiposSAOCOM

The article has some good info

Quote
Five days before launch, the Argentine and SpaceX engineers will conduct a second procedural test, which this time will include the launcher and the satellite.

Are they saying they're going to do the static fire with payload attached?

As far as I know, yes, this is the case. We'll use this test as the last rehearsal before the launch.

PS: I was surprised, too. I thought they stopped doing static fires with the payload attached after AMOS-6.

They did, but it has technically always been up to the customer to have the payload on or not. NASA allowed the DM-1 Dragon to be on the booster for the static fire. Several (all? I haven't been keeping track) of the Starlink static fires have had the Starlinks on top.
DM 1 and 2 were left on the vehicle because it contained an escape system. Starlink is SpaceX owned...it was their choice to leave it intact for the static firing.
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
Cross-post:
Finally, the last test/rehearsal for SAOCOM-1B before launch won't be simultaneous to the static fire, so it will probably be a "regular" SF (no payload attached).
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
An "internal" payload (Starlink), and launch on a once-used first stage.

Could this launch go forward with no Static Fire?
EDIT August 21: Thinking further, Falcon 9 no longer needs range radar to determine if a flight deviation has reached the limits of triggering the destruct package--it's autonomous via GPS use.  Therefore, there's no need to await a range reset of such between launches.

This launch could be as soon as August 28!  That depends on the two previous launches being on-time and successful.

Three launches in three days?!
Scheduled:
Date - Satellite(s) - Rocket - Launch Site - Time (UTC)

2020
August 26 - NROL-44: Orion 10 (Mentor 8 ) (TBD) - Delta IV-H [D-385] - Canaveral SLC-37B - 06:16-10:25
August 27 - SAOCOM-1B, Capella 2 (Sequoia), GNOMES-1 - Falcon 9-092 (B1059.4 L) - Canaveral SLC-40 - 23:19
NET August 28?  Late August  September - Starlink flight 12 (x60) [v1.0 L11] - Falcon 9 (1060.2 S) - Kennedy LC-39A  / Canaveral SLC-40

Changes on August 20th
zubenelgenubi August 21
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline intelati

An "internal" payload (Starlink), and launch on a once-used first stage.

Could this launch go forward with no Static Fire?
EDIT August 21: Thinking further, Falcon 9 no longer needs range radar to determine if a flight deviation has reached the limits of triggering the destruct package--it's autonomous via GPS use.  Therefore, there's no need to await a range reset of such between launches.

This launch could be as soon as August 28!  That depends on the two previous launches being on-time and successful.

Three launches in three days?!

Wouldn't be surprised if they don't.

For SpaceX, I'm sure they have a large enough sample to proceed to launch without a SF.
« Last Edit: 08/24/2020 01:40 pm by intelati »
Starships are meant to fly

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
Cross-post:
Finally, the last test/rehearsal for SAOCOM-1B before launch won't be simultaneous to the static fire, so it will probably be a "regular" SF (no payload attached).
Transfer of the Falcon 9 to the pad and Static Fire should be next.
Noting as of now: We're less than 43 hours from launch and there is no outward sign reported of an impending Static Fire, with or without payload.
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
Cross-post:
Finally, the last test/rehearsal for SAOCOM-1B before launch won't be simultaneous to the static fire, so it will probably be a "regular" SF (no payload attached).
Transfer of the Falcon 9 to the pad and Static Fire should be next.
Noting as of now: We're less than 43 hours from launch and there is no outward sign reported of an impending Static Fire, with or without payload.
SAOCOM-1B launched with no Static Fire.
***

Re: Starlink v1.0 Flight 12:
An "internal" payload (Starlink), and launch on a once-used first stage.

Could this launch go forward with no Static Fire?
Yes, no Static Fire scheduled before September 3 launch.
EDIT: No Static Fire before the September 3 launch.
« Last Edit: 09/04/2020 11:21 pm by zubenelgenubi »
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline Norm38

  • Full Member
  • ****
  • Posts: 1679
  • Liked: 1257
  • Likes Given: 2282
Glad to see they got there.  A huge step towards rapid reuse.

Offline Eka

As far as I know, the leak rumour is only based on a post in Reddit. I would be careful to take such statements for fact.

A good indication of its legitimacy is that it was deleted.
So now I know how to fool you.
No idea why but SpaceX really cracks down on employees whenever they do the PR teams job of being transparent. I've seen a couple of different reddit users talk about SpaceX stuff that turns out to be true and they always delete the post and account an hour or so after posting.
It's disappointing to see SpaceX crack down on transparency but it's a good indication that it's the truth.
All SpaceX employees have NDAs in their employment contracts. This is important because of ITAR related stuff, as well as company secrets. My guess is those posts were in violation of the NDA, and part of the remedy to keep working for SpaceX was to delete the posts and account. As a company that deals with ITAR related stuff, they can't take it lightly and let some slip.
We talk about creating a Star Trek future, but will end up with The Expanse if radical change doesn't happen.

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
It's a few hours over 2 days from the September 17 Falcon 9/Starlink launch, third launch for B1058.
No indications of a Static Fire.

EDIT September 17: Falcon 9 rolled to pad "day of" launch.  (Launch scrubbed today.)
***

The late September launch of Falcon 9/Starlink will be the sixth launch of B1051.  Will there be a Static Fire?  The previous, and first, sixth use of a first stage was Static Fired.
« Last Edit: 10/22/2020 03:12 am by zubenelgenubi »
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline intelati

It's a few hours over 2 days from the September 17 Falcon 9/Starlink launch, third launch for B1058.
No indications of a Static Fire.

The late September launch of Falcon 9/Starlink will be the sixth launch of B1051.  Will there be a Static Fire?  The previous, and first, sixth use of a first stage was Static Fired.

I can see another SF for the sixth launch... More data. Once they have launched it a couple times, I can see them stopping SF for the 6th flights.
Starships are meant to fly

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
It's a few hours over 2 days from the September 17 Falcon 9/Starlink launch, third launch for B1058.
No indications of a Static Fire.

EDIT September 17: Falcon 9 rolled to pad "day of" launch.  (Launch scrubbed today.)
Launch campaign towards a September 27 28 launch apparently includes no Static Fire.
***

GPS III-4 LV is new; Static Fire occurred today at 06:00 EDT.
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
It's a few hours over 2 days from the September 17 Starlink v1.0 Flight 12/Falcon 9 launch, third launch for B1058.
No indications of a Static Fire.

EDIT September 17: Falcon 9 rolled to pad "day of" launch.  (Launch scrubbed today.)
Launch campaign towards a September 27 28 launch apparently includes no Static Fire.
Launch finally occurred on October 6; no Static Fire preceding.
***

Starlink v1.0 Flight 13 Static Fire on October 17, followed by launch on October 18, the sixth launch of B1051.
***

Will there be a Static Fire of B1060.3 before the Starlink v1.0 Flight 14 launch on October 21?

My deduction is no: It's flown two times before--look at the SpaceX Static Fire/no Static Fire track record this year.
Also, this flight is for an "internal" customer.
« Last Edit: 10/20/2020 07:11 pm by zubenelgenubi »
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
Will there be a Static Fire of B1060.3 before the Starlink v1.0 Flight 14 launch on October 21?

My deduction is no: It's flown two times before--look at the SpaceX Static Fire/no Static Fire track record this year.
Also, this flight is for an "internal" customer.

The answer is yes!  Static Fire occurred today circa 1600 UTC.  Launch currently scheduled for October 22.

EDIT: Successful launch October 24.
« Last Edit: 10/25/2020 12:27 am by zubenelgenubi »
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
GPS III-4 LV is new; Static Fire occurred September 25 at 06:00 EDT.
Another Static Fire is expected after the engine removal and replacement, and before launch.
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline Norm38

  • Full Member
  • ****
  • Posts: 1679
  • Liked: 1257
  • Likes Given: 2282
Was there a static fire test?
Not required for internal payloads on a flown booster. Flight by flight determination for flown boosters. All maiden flight boosters are subject to the customary static fire at McGregor and the Flight Readiness Firing (Static Fire) at their assigned pad for that launch. The plan is to phase pad FRF SF's out and only be required to the Quality Assurance Verification Static Fire at McGregor for new boosters. If flight rate stays strong it negates most of the need for the FRF to verify pad systems through ignition sequence post start with shutdown.


I like the logic of this post.  Not sure if this is official SpaceX policy, but I agree with the approach.

But given the engine swaps that were just announced, I expect static fires to be standard practice again for a while.

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
Open question: Will SpaceX perform a Static Fire on the 1st stage for NROL-108?  What does the "customer" want?
Lack of data: We don't know exactly when the launch is, and we don't know which (used) stage it will be. ;D
« Last Edit: 10/27/2020 04:40 pm by zubenelgenubi »
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
GPS III-4 LV is new; Static Fire occurred September 25 at 06:00 EDT.
Another Static Fire is expected after the engine removal and replacement, and before launch.

Successful Static Fire on October 31 EDT.
https://twitter.com/spacex/status/1322702955007541249
Quote
Static fire test complete targeting Thursday, November 5 for Falcon 9 launch of GPS III-4 from SLC-40
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Offline zubenelgenubi

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8455
  • Arc to Arcturus, then Spike to Spica
  • Sometimes it feels like Trantor in the time of Hari Seldon
  • Liked: 4996
  • Likes Given: 45177
Re: Crew-1:
My notes that I took during the press conference, much of this is scattered through the above tweets.
<snip>
Static fire on [November] the 9th.
<snip>
Support your local planetarium! (COVID-panic and forward: Now more than ever.)
My current avatar is saying "i wants to go uppies!"

Tags:
 

Advertisement NovaTech
Advertisement SkyTale Software GmbH
Advertisement Northrop Grumman
Advertisement
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1