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59 votes
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Why can't Falcon 9 fairings touch the water?

The fairings are not boats. While they appear to float (at least for some time), there will also be water on the inside of the fairing. That results in some issues. Inside the fairing, there are ...
DaGroove's user avatar
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56 votes
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Why is Falcon 9's fairing so big?

One of the keys to SpaceX's cost advantage is standardization on common parts. One example is the Merlin engine, which is used on both the first and second stages of the Falcon 9 and Falcon Heavy (...
SafeFastExpressive's user avatar
41 votes

Why can't Falcon 9 fairings touch the water?

In addition to the water damage is the impact damage: the fairings wouldn't "touch" the water they'd hit the water, even with parachute retardation. A net slows deceleration down and spreads it more ...
GdD's user avatar
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40 votes

Reusable spacecraft: why still have fairings detach, instead of open/close?

It would only make sense to keep the fairing attached if the stage it was attached to was going to be recovered. The SpaceX falcon and falcon heavy are multi-stage rockets, only the first stage is ...
GdD's user avatar
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35 votes
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Why aren't payloads their own fairings?

There are a few basic reasons. These include: The aerodynamic model of a fairing needs to be redone with a new fairing design The fairing volume provides a space to ensure the satellite is kept cool ...
PearsonArtPhoto's user avatar
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32 votes
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What makes 21st century fairings so valuable that they'd potentially be recovered and re-used?

It is not so much that in the 21st century it is hard or expensive to make a fairing. Rather they are just REALLY REALLY big. 13 meters by 4.6 meters. That is about 40 feet long, and 14 feet wide....
geoffc's user avatar
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28 votes
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Are SpaceX Falcon rocket boosters significantly cheaper to operate than traditional expendable boosters?

We don't know. One thing we do know is that SpaceX launches are fairly cheap compared to their competitors. Whether that is because of reuse, because their rockets are generally cheaper independent of ...
Jörg W Mittag's user avatar
27 votes

Reusable spacecraft: why still have fairings detach, instead of open/close?

The fairings are detached to prevent carrying their un-necessary mass to orbit. This typically happens during the second stage burn. See this question for information about the timing of fairing ...
Organic Marble's user avatar
25 votes
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What happens to payload fairings of GEO launches?

A payload fairing is separated as soon as possible when the air is so thin that the payload needs no protection anymore. This reduces the weight of the remaining rocket. The fairing is usally ...
Uwe's user avatar
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24 votes
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How strong and "hot" is the wind on the payload after the fairing is deployed at ~110km?

Launch vehicle operators (or at least the major ones) all seem to drop their fairings such that the heat produced by the remaining atmosphere remains below 1135 W/m$^2$. Not all the operators provide ...
awksp's user avatar
  • 1,079
24 votes

Why aren't payloads their own fairings?

Supplementary to other answers which describe why most payloads aren't their own fairings: We do actually launch some payloads that are somewhat closer to being their own fairings - manned spacecraft....
Jack's user avatar
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23 votes
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Will SpaceX attach its fairings to a booster to recover them?

The plan as has dribbled and drabbled out from Musk's various statements is that the fairings are large and light, thus reentry heating is not too bad on them. They do not need to do a re-entry burn ...
geoffc's user avatar
  • 79.8k
23 votes

What makes 21st century fairings so valuable that they'd potentially be recovered and re-used?

The fairings are large structures, made in a way that's difficult to automate. The structure consists of an aluminium honeycomb core with carbon fibre inner and outer panels laminated onto it. Carbon ...
Hobbes's user avatar
  • 128k
23 votes

Why aren't payloads their own fairings?

A fairing like the one SpaceX uses on the Falcon 9 weighs on the order of 2 tons. That's a lot of extra weight to add to the satellite. Satellites are usually covered in components that need to be ...
Hobbes's user avatar
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21 votes
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How can the 6.5 m primary mirror of the JWST fit inside the 5.4 m fairing of Ariane 5?

The JWST is made to fold up, to fit inside the standard fairing. You can sort of see this in your image, 3 mirror segments are visible (the hexagons in the middle), other segments are viewed side-on ...
Hobbes's user avatar
  • 128k
21 votes

Are SpaceX Falcon rocket boosters significantly cheaper to operate than traditional expendable boosters?

While most of the information is private, since SpaceX is not even a publicly traded company, there is some information we can discern. In 2020 SpaceX launched 26 times (1 for In Flight Abort, was a ...
geoffc's user avatar
  • 79.8k
16 votes

On large diameter Atlas V fairings, why is the Centaur inside the fairing?

A document from NASA Safety & Mission Assurance suggests the reason is structural: Thin-­skinned Centaur cannot easily support the giant 5.4 meter diameter payload fairing, so the Contraves ...
Russell Borogove's user avatar
15 votes
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Falcon 9 fairings cost and reusability

Apparently this was considered by SpaceX in Q1 2015, to work around a production bottleneck. Due to delays in 2015 after the June 2015 loss of CRS-7 that bottleneck may not have occurred. As of CRS-8 (...
Hobbes's user avatar
  • 128k
15 votes

Why aren't smaller fairings used for smaller payloads?

Getting parts space-qualified is a very expensive and lengthy process. It does not make any economic sense to build one-offs. In particular, unlike any other currently operating orbital launch vehicle,...
Jörg W Mittag's user avatar
14 votes

Pressure inside a launch fairing - falcon 9

While I have no specific knowledge of Falcon 9's fairing, it is common for compartments of space vehicles to be purged or pressurized slightly above ambient while on the pad to keep contamination out ...
Organic Marble's user avatar
13 votes

What happens to payload fairings of GEO launches?

Like the first stage, SpaceX catches them and reuses them Or at least that's the plan. They had their first successful single fairing catch in January this year, and their first successful double ...
Graham's user avatar
  • 1,930
12 votes

Falcon 9 fairings cost and reusability

The fairings cost several million dollars. During the post launch briefing of CRS-8, Elon Musk mentioned that: A few more things we want to do... we want to try to bring back the fairing - the ...
hshib's user avatar
  • 609
12 votes

Do 'size of a bus' sized F9 fairings ever float after impact? Are they navigation hazards?

The fairing consists of an aluminium honeycomb sandwiched between carbon fibre sheets. The amount of air trapped in the honeycomb determines if the structure will float, but as we don't know how thick ...
Hobbes's user avatar
  • 128k
12 votes
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Are all payload fairings this floppy?

That ULA video was great. I googled for "fairing vibrational modes after jettison" and came up with a lot of interesting links. The prize is probably this paper "Simulation of the behavior of a ...
Organic Marble's user avatar
12 votes
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What makes it so hard to precisely land a fairing?

The fairing itself is large, (a pair can enclose a school bus sized payload) and is very light, and not very aerodynamic when split into two halves. When joined together it is very aerodynamic, when ...
geoffc's user avatar
  • 79.8k
12 votes

Why can't Falcon 9 fairings touch the water?

One of the biggest concerns in spacecraft is keeping them free of contaminants. Spacecraft are often built in clean rooms to keep them free of any such thing. Landing in salt water would leave residue ...
PearsonArtPhoto's user avatar
  • 121k
12 votes

Reusable spacecraft: why still have fairings detach, instead of open/close?

Apart from the mass penalty of carrying the fairing through the entire flight that Organic Marble mentioned, a hinged fairing and the mechanism to open and close it would be much more expensive, ...
Russell Borogove's user avatar
11 votes
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Do 'size of a bus' sized F9 fairings ever float after impact? Are they navigation hazards?

Finally can answer this definitively, yes, they do float and I can prove it! Mr Steven failed to catch the fairing in its net, which looks like this: But after the water landing it was fished out. ...
geoffc's user avatar
  • 79.8k
10 votes
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Pressure inside a launch fairing - falcon 9

Are launch fairings pressurized to 1 atmosphere for the benefit of the cargo? No, pressure within the fairing will drop gradually during the launch. The reason for the pressurization system is to ...
Bit Chaser's user avatar
10 votes
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How much does a current F9 fairing-half weigh?

While we wait for an authoritative answer, I'm going to guesstimate here, and answer your second question in the process. "Is this resting on something, or is it really floating this high in the ...
Diego Sánchez's user avatar

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