Falcon 9 Block 5 Updates and Discussion

[STS-200]

When I play Kerbal, and I'm re-entering at high altitude, If I leave stability control on, initially pointing perfectly prograde (0 AoA), as I drift over the planet, my AoA rises relative to prograde -- is the same sort of thing you are describing?

It sounds like it. If you hold a space-fixed attitude during orbit or entry, AoA will increase due to the curvature of the flight path around the Earth.

Off topic for a moment - I don't know how Kerbal handles these things, but spacecraft don't hold a space-fixed attitude during re-entry. Lifting entries will control AoA (and/or roll) to shape their entry path.

[octavo]

Off topic for a moment - I don't know how Kerbal handles these things, but spacecraft don't hold a space-fixed attitude during re-entry. Lifting entries will control AoA (and/or roll) to shape their entry path.

Uncontrolled, your craft will continue to rotate during orbit, such that in half an orbit you will be turned 180 degrees, and once you complete the orbit, you will be again facing the same direction you were before. I believe that's accurate physics?

Once you reenter, you can fly manually or tell the craft to hold a prograde attitude. I generally aim for 10 - 15 degrees above prograde most of the way down, as this seems to balance bleeding off speed without dropping too low too quickly. [/off-topic]

[FutureSpaceTourist]

Bumping for the 5th anniversary of the first flight of Block 5. Those 5 years have seen 169 F9 and 5 FH orbital launches, all successful.

[wannamoonbase]

Bumping for the 5th anniversary of the first flight of Block 5. Those 5 years have seen 169 F9 and 5 FH orbital launches, all successful.

I was recently thinking about how much anticipation there was for the Block 5.

It's turned out to be a beast of a rocket!


Edit: 169 flights in 5 years and maybe 100+ in the next 1 year.  Truly nuts!

[ugordan]

Bumping for the 5th anniversary of the first flight of Block 5. Those 5 years have seen 169 F9 and 5 FH orbital launches, all successful.

Has it been 5 years already? Jesus...

[zubenelgenubi]

Cross-post; Axiom Mission 2 Flight Readiness Review:

Space X certifying Falcon 9 for 20 missions with Starlink, stepping up booster production to support Heavy flights.

This is a result of the "deep-dive" examination of B1060.16?  We should see it and B1058.16 return to flight soon?

[wannamoonbase]

Cross-post; Axiom Mission 2 Flight Readiness Review:

Space X certifying Falcon 9 for 20 missions with Starlink, stepping up booster production to support Heavy flights.

This is a result of the "deep-dive" examination of B1060.16?  We should see it and B1058.16 return to flight soon?

That makes it sound like they expect 20 flights to be the limit.  Originally was it not discussed that they could do 100 flights on the fuselage after engine changes?

Yesterday, I started to think that the Merlin's are very impressive to handle 20 flights, and what a shame it is to have these FH center cores dropping 9 brand new Merlin's in the ocean after 1 flight.  Would it be worth it financially to trade out an older set of Merlins into a FH center core and keep the fresh Merlins so they can put more flights on them.

[Vettedrmr]

Yesterday, I started to think that the Merlin's are very impressive to handle 20 flights, and what a shame it is to have these FH center cores dropping 9 brand new Merlin's in the ocean after 1 flight.  Would it be worth it financially to trade out an older set of Merlins into a FH center core and keep the fresh Merlins so they can put more flights on them.

I know I assumed the engines were new, but do we know that the center core only has new engines?

[Zed_Noir]

Yesterday, I started to think that the Merlin's are very impressive to handle 20 flights, and what a shame it is to have these FH center cores dropping 9 brand new Merlin's in the ocean after 1 flight.  Would it be worth it financially to trade out an older set of Merlins into a FH center core and keep the fresh Merlins so they can put more flights on them.

The labor cost & time to move an older set of Merlins from an older core to a new FH center core along with installing a new set Merlins to the older core seems to cost more than just installing new set of engines in the FH center core to begin with.

SpaceX is trading dumping a few Merlins in the ocean to maintain launch cadence toward their goal of 100+ launches for 2023.

[DanClemmensen]

Would it be worth it financially to trade out an older set of Merlins into a FH center core and keep the fresh Merlins so they can put more flights on them.

Since the FH has no competition, they can charge pretty much whatever they want. This means that there is almost no incentive to reduce the cost of an FH launch. The incremental cost savings would be modest, so passing the savings on to the customer would have effectively no effect on the increasing the demand for launches, and just keeping the profit would have little effect on the bottom line.

SpaceX probably does not want to increase FH launches anyway. Each FH launch occupies LC-39A for roughly the equivalent of 3(?) F9 launch slots, so as the availability of launch slots becomes a bottleneck, the opportunity costs of these F9 slots must be added to the FH cost.

[Robotbeat]

On the contrary, SpaceX still has plenty of incentive to reduce COST even if they don’t have to reduce PRICE.

[wannamoonbase]

Would it be worth it financially to trade out an older set of Merlins into a FH center core and keep the fresh Merlins so they can put more flights on them.

Since the FH has no competition, they can charge pretty much whatever they want. This means that there is almost no incentive to reduce the cost of an FH launch. The incremental cost savings would be modest, so passing the savings on to the customer would have effectively no effect on the increasing the demand for launches, and just keeping the profit would have little effect on the bottom line.

SpaceX probably does not want to increase FH launches anyway. Each FH launch occupies LC-39A for roughly the equivalent of 3(?) F9 launch slots, so as the availability of launch slots becomes a bottleneck, the opportunity costs of these F9 slots must be added to the FH cost.

I think your ideas contradict themselves.  IF they can charge what they want, then why be concerned about how much time a FH takes up LC39A.

SLC40 is doing the heavy lifting while 39A is used for FH and Dragon flights.

SpaceX is spending boat loads of money on Starship and Starlink, they have all the reasons in the world to save costs wherever they can.

[DanClemmensen]

On the contrary, SpaceX still has plenty of incentive to reduce COST even if they don’t have to reduce PRICE.

Why? just increase the PRICE. That was my original point. Monopoly pricing (and costing) is different. FH launch cadence is so low that it's not worth the hassle. the cost difference between nine new Merlins and refurbishment/transport/etc. of nine used Merlins is not all that high.

There will probably be fewer than 20 more FH launches, ever, so it doesn't matter much either way.

[alugobi]

the cost difference between nine new Merlins and refurbishment/transport/etc. of nine used Merlins is not all that high.

How much is the difference?

[wannamoonbase]

On the contrary, SpaceX still has plenty of incentive to reduce COST even if they don’t have to reduce PRICE.

Why? just increase the PRICE. That was my original point. Monopoly pricing (and costing) is different. FH launch cadence is so low that it's not worth the hassle. the cost difference between nine new Merlins and refurbishment/transport/etc. of nine used Merlins is not all that high.

There will probably be fewer than 20 more FH launches, ever, so it doesn't matter much either way.

So why not raise the price and save the money on a engine swap and maximize the profit? 

[Robotbeat]

Exactly. This is not for a cost plus contract so there isn’t any incentive at all to increase cost like this:

[Martin_G]

Did Falcon 9 get a performance upgrade recently?

We saw a RTLS for the first time with AX-2, a crewed mission to the ISS. It used a brand new booster.

Starlink 6-x up to now only used newer boosters, even when the rotation suggested an "older" one. ls that coincidence, or do they require some extra performance?

[spacenuance]

Did Falcon 9 get a performance upgrade recently?

We saw a RTLS for the first time with AX-2, a crewed mission to the ISS. It used a brand new booster.

Starlink 6-x up to now only used newer boosters, even when the rotation suggested an "older" one. ls that coincidence, or do they require some extra performance?

SpaceX have been pushing Falcon through starlink missions for a while, both on the first stage and second stage performance. You may have also noticed that they performed a single engine entry burn and 1-3-1 landing burn, a profile they first demonstrated on the Transporter 7 mission. They already had quite a good margin for Crew missions with an ASDS landing, and they were able to show NASA through all the optimizations they have done with starlink missions that they could cut off the first stage about 10km lower and 700km/hr slower and still have enough performance and decent margin in the second stage to get to orbit.

[M.E.T.]

Does Crew Dragon still weigh ~12.5t?

[wannamoonbase]

Did Falcon 9 get a performance upgrade recently?

We saw a RTLS for the first time with AX-2, a crewed mission to the ISS. It used a brand new booster.

Starlink 6-x up to now only used newer boosters, even when the rotation suggested an "older" one. ls that coincidence, or do they require some extra performance?

SpaceX have been pushing Falcon through starlink missions for a while, both on the first stage and second stage performance. You may have also noticed that they performed a single engine entry burn and 1-3-1 landing burn, a profile they first demonstrated on the Transporter 7 mission. They already had quite a good margin for Crew missions with an ASDS landing, and they were able to show NASA through all the optimizations they have done with starlink missions that they could cut off the first stage about 10km lower and 700km/hr slower and still have enough performance and decent margin in the second stage to get to orbit.

I agree that it is more likely to do with the experience in flying the booster and the data collected.  They probably continue to make some improvements, but that is likely small improvements at this point, weight wise.  But timing of events, trajectories, residual amounts, they're squeezing out little bits here and there.