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30 minutes ago, zolotiyeruki said:

Uh, correct me if I'm wrong about this, but isn't the whole point of the sealed bid process to encourage the bidders to put forth their last, best offer?

Kind of?

There is a lot of game theory involved. It's not actually obvious that sealed bid silent auction results in the best price. Each bidder is still bidding against not only the value but also the other bidders. If you think, for instance, that A and B are going to bid high, you as C can bid almost as high, as long as you end up low bidder. So that's not necessarily getting the best price.

https://en.wikipedia.org/wiki/First-price_sealed-bid_auction

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The interesting thing in that wikipedia article I posted is the part about "second price" auctions. The way those work is that bidder who makes the highest bid (or in this case it would be the lowest bid) still wins the auction, but the price they pay is the price of the second-highest bidder. Unlike first-price bidding, where the incentive is to bid against the other bidders, in second-price bidding the incentive is simply to make a fair bid of what you value the winning to be.

However -- such game theory ignores "irrational" motivation. So if you really want to win and don't care if you lose (objective) value, it throws the premise of the game theory out the window.

For instance: if you represent a company that plans to otherwise build its own moon lander even with no external customer, you might be willing to bid way below cost, because any award at all is still a marginal value over the "nothing" that you were expecting to get from your self-funded project.

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5 minutes ago, mikegarrison said:

Kind of?

There is a lot of game theory involved. It's not actually obvious that sealed bid silent auction results in the best price. Each bidder is still bidding against not only the value but also the other bidders. If you think, for instance, that A and B are going to bid high, you as C can bid almost as high, as long as you end up low bidder. So that's not necessarily getting the best price.

https://en.wikipedia.org/wiki/First-price_sealed-bid_auction

And when it come to that sort of thing, SpaceX may be a “space contract shark”. The DoD/FH contract appeared high by SpaceX standards (possibly not depending on what is in the contract), and it can be assumed Starbase etc is a bit of a money pit. So it’s understandable that others may have thought the SpaceX bid would be higher. 

Kinda smells like a pool shark to me

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2 hours ago, mikegarrison said:

The interesting thing in that wikipedia article I posted is the part about "second price" auctions. The way those work is that bidder who makes the highest bid (or in this case it would be the lowest bid) still wins the auction, but the price they pay is the price of the second-highest bidder. Unlike first-price bidding, where the incentive is to bid against the other bidders, in second-price bidding the incentive is simply to make a fair bid of what you value the winning to be.

However -- such game theory ignores "irrational" motivation. So if you really want to win and don't care if you lose (objective) value, it throws the premise of the game theory out the window.

For instance: if you represent a company that plans to otherwise build its own moon lander even with no external customer, you might be willing to bid way below cost, because any award at all is still a marginal value over the "nothing" that you were expecting to get from your self-funded project.

Even in that situation, though, both parties (buyer and seller) win--the buyer pays less than they otherwise would, and the seller gets more than they otherwise would.

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Is there a name for the type of bidding where preliminary bids include a dollar value, then the final bidding is sealed?

Was the game play here that SpaceX could not possibly have been serious about ~$2B, and they would grossly increase the real bid from there?

The other 2 players flip-flopped their bid values, but SpaceX only increased their bid by a few hundred M$.

2 hours ago, mikegarrison said:

For instance: if you represent a company that plans to otherwise build its own moon lander even with no external customer, you might be willing to bid way below cost, because any award at all is still a marginal value over the "nothing" that you were expecting to get from your self-funded project.

This was SpaceX I think. They are making SS regardless.

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6 hours ago, mikegarrison said:

The interesting thing in that wikipedia article I posted is the part about "second price" auctions. The way those work is that bidder who makes the highest bid (or in this case it would be the lowest bid) still wins the auction, but the price they pay is the price of the second-highest bidder. Unlike first-price bidding, where the incentive is to bid against the other bidders, in second-price bidding the incentive is simply to make a fair bid of what you value the winning to be.

However -- such game theory ignores "irrational" motivation. So if you really want to win and don't care if you lose (objective) value, it throws the premise of the game theory out the window.

For instance: if you represent a company that plans to otherwise build its own moon lander even with no external customer, you might be willing to bid way below cost, because any award at all is still a marginal value over the "nothing" that you were expecting to get from your self-funded project.

This, now the moon landing contract probably shifted spaceX focus quite a bit. Don't think they planned on moon misions before they had an manned starship flying. 
But moonship is not an major modification and helps them learn a lot in addition to getting paid for it. 

Now BO should have more money than spaceX but they had partners who needed profit. 

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Lift has gone down, first grid fin installed! It wiggles a bit earlier, presumably a little test of the mechanism

Also, it is possible that what we see under the attachment points is the load point where the booster is to be caught in the future

Finally, the text on the grid fin says gridfin#4, so it's possible they are all already at starbase

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Heard rumours that the grid fins won’t fold down for ascent, but will stay in that extended position the whole flight. I hope the guy who told me that just had bad info, cause that is properly cursed. I know passive stability isn’t even a consideration on modern-day rockets, and on Starship especially would be a lost cause, but picture the whole stack flying up with the grid fins out and tell me that doesn’t just look wrong.

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36 minutes ago, RyanRising said:

Heard rumours that the grid fins won’t fold down for ascent, but will stay in that extended position the whole flight. I hope the guy who told me that just had bad info, cause that is properly cursed. I know passive stability isn’t even a consideration on modern-day rockets, and on Starship especially would be a lost cause, but picture the whole stack flying up with the grid fins out and tell me that doesn’t just look wrong.

That's unlikely, they would be quite useless in that position even compared to the N1 where they proved to be underpowered. I believe that rumour came out just because they were attached to B4 extended

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2 hours ago, RyanRising said:

Heard rumours that the grid fins won’t fold down for ascent, but will stay in that extended position the whole flight. I hope the guy who told me that just had bad info, cause that is properly cursed. I know passive stability isn’t even a consideration on modern-day rockets, and on Starship especially would be a lost cause, but picture the whole stack flying up with the grid fins out and tell me that doesn’t just look wrong.

There is some speculation on NSF that the grid fins being installed right now are nonfunctional props for the full-stack photo-op, because there's no visible articulation, not even as a control surface.

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40 minutes ago, Beccab said:

That's unlikely, they would be quite useless in that position even compared to the N1 where they proved to be underpowered. I believe that rumour came out just because they were attached to B4 extended

What was the purpose of N1 grind fins? I assumed it was related to staging or abort. 

And it makes no sense to launch with the grind fins out, they add plenty of drag for one. 
Agree with other its either an fitting test or photo shot. 

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25 minutes ago, magnemoe said:

photo shot

...would be a stupid vanity project. 

I can see fitting and testing... But I hope they don't try to fly that way (besides - won't they have to unstack to replace the 'for show' fins with working ones?) 

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2 hours ago, Beccab said:

Worst case Tim Starbase tour video, best case that long awaited elon interview about SpaceX

I blew up that photo and the pattern is very curious. It looks like there are spacers between some of the tiles?

But the straight seam solution was clearly the straightforward one. 

1 hour ago, magnemoe said:

What was the purpose of N1 grind fins? I assumed it was related to staging or abort. 

My understanding is that the central ring of engines on the N-1 did not have particularly good gimbal range and so the grid fins were intended for roll control. I don’t think they worked very well, though.

In contrast, the four large fixed fins on the Saturn V were only there to provide passive aerodynamic stability in an abort scenario. IIRC the vehicle had more passive stability than expected and so if crewed flights had continued much longer they would have axed the fins. The only reason that the Skylab launch had the fins was because it was the booster intended for Apollo 18.

1 hour ago, magnemoe said:

And it makes no sense to launch with the grind fins out, they add plenty of drag for one. 
Agree with other its either an fitting test or photo shot. 

Fit test makes perfect sense. They do a lot of those. 

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Also, confirmed non-folding gridfins:

If you think about it, an extended grid fin might be less draggy than a folded one. They're designed for aerodynamic steering, not drag. 

Falcon 9's grid fins can hide in the aerodynamic 'shadow' of the fairing, whereas Starship is a constant 9m diameter. So the surface area of the extended fin might be less than the top surface of the same fin while it's folded, hence the decision to keep the fins fixed.

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15 minutes ago, RealKerbal3x said:

If you think about it, an extended grid fin might be less draggy than a folded one. They're designed for aerodynamic steering, not drag. 

Just checked, on the way up Max Q is ~1400 kph at 11 km. On the way down, at 11 km it's doing ~1900 kph.

Also tighter to the airframe.

Not having a hinge not only reduces part count, but it is also almost certainly stronger—in case they have grid fins as lift/catch points?

Having a "dead" grid fin might also allow control with the remaining 3 as well as it is still functioning as a neutral gridfin.

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43 minutes ago, tater said:

Just checked, on the way up Max Q is ~1400 kph at 11 km. On the way down, at 11 km it's doing ~1900 kph.

Also tighter to the airframe.

Not having a hinge not only reduces part count, but it is also almost certainly stronger—in case they have grid fins as lift/catch points?

Having a "dead" grid fin might also allow control with the remaining 3 as well as it is still functioning as a neutral gridfin.

It looks absolutely accursed.

But, as I once pointed out: if duct taping fresh hot chicken sandwiches to the fairing would improve aerodynamics, rocket engineers would make a Chick Fil A run before every launch.

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