SpaceX progress towards a 100 launch year

[2megs]

Like my GPA in college, if you fall behind the required average early on it gets harder to make up.  While we can expect them to gain some efficiencies, the cycle time of the ASDS's, weather, range and payload delays, I think 100 will be very hard, not impossible, to meet.

They'll need some RTLS or expendable flights to help out and as many Vandy launches as possible.

Myself, I'm predicting 85-90 flights total for the calendar year.

I suspect your GPA wasn't exponential...

The point, in both cases, is that there's an upper limit on what you can put into the running average.

Once you have three C's with a GPA of 2.0, no amount of academic excellence in your next class will let you throw a 10 into the mix to get your average up to 4.0.

Similarly, if SpaceX suffers a 20-day gap between barge landings, they can't land on the same barge 1 day later to get back to the needed average of <11 days.

And that's the pace. Either they average one launch out of every pad every 10.95 days, or they don't make it to 100. Meanwhile, ASDS turnaround is ~9 days, so even with 365 days of calm seas the upper limit is ~120 ASDS landings per year. There's not much distance between those numbers; if they fall more than a tiny bit behind the pace, they can't catch up to the pace with ASDS missions.

And so the pace to 100 will require either extraordinarily consistent weather, or increasing the percentage of RTLS and expended missions, or adding another drone ship.

[Bob Shaw]

My back of the envelope calculations tell me that 90 is about the maximum they can do, and even that depends on two things - no inflight failures and, of course, the weather. SpaceX have been remarkably successful in terms of their launcher reliability and may continue to do so as they push the flights per booster limit to the right but they have no control over the weather and if they must depend in Florida to hit their high targets then it is risky. I hope they make 90, or even 80 - either of these would be an astonishing accomplishment.

[Robotbeat]

What is your math?

[freddo411]

Like my GPA in college, if you fall behind the required average early on it gets harder to make up.  While we can expect them to gain some efficiencies, the cycle time of the ASDS's, weather, range and payload delays, I think 100 will be very hard, not impossible, to meet.

They'll need some RTLS or expendable flights to help out and as many Vandy launches as possible.

Myself, I'm predicting 85-90 flights total for the calendar year.

I suspect your GPA wasn't exponential...

The point, in both cases, is that there's an upper limit on what you can put into the running average.

Once you have three C's with a GPA of 2.0, no amount of academic excellence in your next class will let you throw a 10 into the mix to get your average up to 4.0.

Similarly, if SpaceX suffers a 20-day gap between barge landings, they can't land on the same barge 1 day later to get back to the needed average of <11 days.

And that's the pace. Either they average one launch out of every pad every 10.95 days, or they don't make it to 100. Meanwhile, ASDS turnaround is ~9 days, so even with 365 days of calm seas the upper limit is ~120 ASDS landings per year. There's not much distance between those numbers; if they fall more than a tiny bit behind the pace, they can't catch up to the pace with ASDS missions.

And so the pace to 100 will require either extraordinarily consistent weather, or increasing the percentage of RTLS and expended missions, or adding another drone ship.

A couple of related points:

* FH launches maybe RTLS only.   Several FH launches scheduled this year
* a couple of launches from BC this year
* Perhaps the barge turn arounds can be made faster?   A tug that moves barges faster?   Different trajectory so barges don't travel as far?
* Another barge -- why not?

My first guess is that SX will simply run their current operational tempo, and very nearly hit 100.

Second guess is there will be small incremental improvements, maybe out of the list above to increase tempo a bit.

[edkyle99]

How many launches until Starlink is completed?  At that point the question will be how low the launch rate will fall.

 - Ed Kyle

[kevin-rf]

Don't forget to take into account, several non-heavy RTLS missions. For instance Transporter missions and many of the commercial Vandenberg missions.

[rpapo]

How many launches until Starlink is completed?  At that point the question will be how low the launch rate will fall.

 - Ed Kyle

They have a long way to go yet, with roughly 2,100 of around 10,000.  And even after it is "completed" they will still need to launch regularly to replace satellites that have run out of fuel or which they deorbit as obsolete.  What exactly that launch rate will be I have no idea.

[tbellman]

How many launches until Starlink is completed?  At that point the question will be how low the launch rate will fall.

At 30 000 satellites (if their full generation 2 gets approved), satellites being planned to be replaced every five years (which is what they have said their plans are), and say 60 satellites per Starship launch, that gives a steady-state rate of 100 launches per year.

[alugobi]

After today, there are 311 days remaining in the year.  They've launched 12. 

311/88=3.53 days per launch to make 100.

[alugobi]

From Eric Berger's periodic Rocket Report, https://link.arstechnica.com/view/5d89234efc942d47888534bdi8qgx.1yb/cf3ca4a1

Though the article is primarily about SX's revenue for this year, there is a projection of their launch rate to obtain that.  Emphasis mine:

SpaceX may see a significant increase in 2023 revenue. Payload's Mo Islam has released his projection for SpaceX's revenue in 2023 and predicts the company will draw in $11.5 billion this year. If true, this would represent a substantial leap from his predicted revenue for 2022 of $4.6 billion.  ...

Is SpaceX now a satellite company first? ... As part of these projections, Islam expects 87 orbital launches in 2023 for SpaceX, with a sizable jump in revenue from commercial Falcon 9 and government Falcon Heavy missions.

[litton4]

How many launches have they done since 25th Feb 2022 (ie the last rolling calendar year)?

A quick count from the manifest, suggests 66, correct me someone?
In a couple of days, I think it will be 67, with 2 launches and one dropping off the bottom.

[spacenut]

Will the chart be updated around the first of every month?  I like the simple line and dot chart. 

[xyv]

Yes.  End of every month I plan to update it.  Probably I will just replace the chart at the begining of the the thread.  I see a lot of speculation on rate versus falling behind etc.  I added last year for comparison - if people like this (I do) I will start using it for the update.  Shows the value of a goal.

Just for reference, if all three launches go off tomorrow, they will be just on/under the line again.

[AmigaClone]

I like the chart showing last year since it demonstrates that for much of the year SpaceX was not going on a 61 launch pace, but they caught up in the second half of the year.

[Robotbeat]

Yes.  End of every month I plan to update it.  Probably I will just replace the chart at the begining of the the thread.  I see a lot of speculation on rate versus falling behind etc.  I added last year for comparison - if people like this (I do) I will start using it for the update.  Shows the value of a goal.

Just for reference, if all three launches go off tomorrow, they will be just on/under the line again.

Can you share the spreadsheet file for that? I want to compare with an exponential curve (that also gets to a 100/year launch rate). I think exponential curve is much more appropriate than linear here.

[xyv]

Sure, no problem.  It's really basic - just a scatter plot and a two point line to compare against.  I've attached it to this post.

[eeergo]

Yes.  End of every month I plan to update it.  Probably I will just replace the chart at the begining of the the thread.  I see a lot of speculation on rate versus falling behind etc.  I added last year for comparison - if people like this (I do) I will start using it for the update.  Shows the value of a goal.

Just for reference, if all three launches go off tomorrow, they will be just on/under the line again.

Can you share the spreadsheet file for that? I want to compare with an exponential curve (that also gets to a 100/year launch rate). I think exponential curve is much more appropriate than linear here.

Why? Rate is approximately constant (see last year's), why should it accelerate in such a pronounced manner as the year goes by? Moving average pace increase doesn't show such an exponential behavior either: https://forum.nasaspaceflight.com/index.php?topic=58240.msg2455547#msg2455547

[Robotbeat]

Why would the launch rate jump unnaturally because it’s a new year instead of smoothly increasing over time as SpaceX improves capability?

And actually it does show an exponential increase. Exponential just means the rate increases over time and compounds. It doesn’t mean it shoots up. A bank account with a 2% annualized return is increasing exponentially.

[eeergo]

Why would the launch rate jump unnaturally because it’s a new year instead of smoothly increasing over time as SpaceX improves capability?

And actually it does show an exponential increase. Exponential just means the rate increases over time and compounds. It doesn’t mean it shoots up. A bank account with a 2% annualized return is increasing exponentially.

Because of increased yearly launch objectives or other managerial factors that don't depend on differential continuous acceleration.

You can have a trend that follows an exponential with coarse/long enough binning (for example, the annualized bank account return you mention, or even SpaceX's launch rate if using yearly bins - I don't know about this one, would have to check), but doesn't in the short term.

Or alternatively, a linearized approximation over short time bins might be much preferrable because the short-term increase isn't well-fitted by an exponential, or the exponent is too small to show up over the noise.

For an obvious example, check out both the 1-year-window and the 10-day-window moving average curves for 2021 in the post I linked to above. Attempting to fit those datapoints (in a year with 30-something launches) to an exponential would give you junk results, since the trend is practically flat that year. Actually, fitting the second half of the year would give you a *negative* exponential in both instances. Doesn't matter if the multi-year trend shows something else: fitting a shorter window won't necessarily give you something similar.

The figures produced by xyv clearly show a linear trendline fits the data very closely. Try it out yourself now you have the data: what's the R for both trends, and what exponent do you get forcing an exponential fit?

[Robotbeat]

An exponential increase is the most natural and obvious one. SpaceX can’t obviously flip a switch and change every single bottleneck of flightrate. It’s ludicrous to think so. Exponential increase is from making a whole bunch of incremental improvements that occur roughly stochastically over the year.

And of COURSE a linear function fits a curve if you look at a very short portion of the curve, that’s literally true for basically every smooth (and non-pathological) function!

If linear fits so well, then (if you mean linear increase) tell me what year SpaceX had a negative launch rate? Or (as I assume you mean linear cumulative launches) did they have a 100 year launch rate last year, too?

To make linear work requires just a bunch of overfitting and piecewise assumptions. It’s a crap model and actually over-complicated, requiring a bunch more assumptions.

(A logistical or sigmoidal function I could take more seriously, ie that it would plateau soon… but exponential is just the most simple model.)