Fully fueled space shuttles, Apollo spacecraft, etc., seem simultaneously heavy and delicate. I’ve often wondered what part of the spacecraft, or what kind of apparatus is bearing this load when it is sitting on the pad. I’ve looked at several pictures but can’t see how this is accomplished.
I believe it’s done by pressurizing the container. The older museum exhibits had to be pressurized to stand up on display.
Is that even an answer to this question?
Yes, yes it is. Also, in many missiles (like the Minuteman), the solid motor fuel is designed and shaped to assist in bearing the load above it.
Tripler
- Rocket surgeon.
Okay, but that rocket isn’t sitting on it’s nozzle, so if I read the OP right… what’s it sitting on? A jet aircraft clearly has 3 struts bearing it’s weight while on the ground, but what’s the corollary for pad-bound rockets?
From this picture, it looks like the boosters just sit on the platform
http://blog.al.com/space-news/2009/05/atlantis_padr.jpg
and the shuttle is held by other structures, and is presumably usefully glued to the boosters as well.
http://scienceblogs.com/startswithabang/upload/2010/08/how_to_launch_a_space_shuttle/gpw-20051129-NASA-GPN-2000-001877-looking-directly-down-at-STS-79-Space-Shuttle-Atlantis-Florida-19960820-medium.jpeg
I misunderstood the OP then. I never did ask that question, but did see diagrams that there’s a mundane retention ring holding the whole thing up off the silo floor. But knowing cutbacks in the Air Force, they’ve probably replaced it with a couple of cinder blocks.
Tripler
They stole them from Biden’s IROC-Z when he wasn’t looking.
This was (is) true for some, but not for the Shuttle nor the Saturns nor I think any manned booster. The Shuttles are stacked and transported in the same VAB and by the same ‘crawler’ that was built for & used by Apollo and they are most definitely not rolled out fueled (i.e. pressurized), but completely empty. They are only fueled at the pad.
The weight is taken by the structure of the booster itself and its attachment points to the pad. It’s complicated & unique for each design and doesn’t really have a universal answer, other than as stated, ‘really big Space Bolts!’
P.S.
Here’s a really really cool super slow-mo video showing the very base of a Saturn V during launch with a narration that describes, among other things, its hold downs…
neat video clip. Of course that lead me to wander around the net and I was surprised that we’re using Russian engines on the Atlas 5.
They’re held down by giant explosive bolts.
The structure of the rocket has to support its own weight, of course, otherwise it’d collapse as it begins its upward acceleration (>1g).
The rocket’s ability to support (g multiples of) its own weight is sometimes dependent on the tank pressure (as in the old Atlases and the Centaur upper stage). Even in vehicles that can stand on their own with no pressure in the tanks, tank pressure does provide an important stabilizing effect. The vehicle couldn’t be subjected to as high an acceleration if not for the tank pressure.
Solid rocket fuel only supports itself. It isn’t stiff enough to support anything above it. The motor case provides all the support.
This static display of a Saturn 5 shows the point which bears all the weight.
This picture on the launch pad shows the hold downs.
