Saturn V rocket needed to be 266 times bigger.

[Sticks]

The intro did seem quite seductive , many thanks for pointing out the fatal flaws yet again

Q1. Who was it that twigged that the three stage approach would achieve this.

Q2. Was Von Braun not involved with the space programme during the Apollo missions?

Q3 The FAQ's on that site, have they been answered ppoint for point either here, Clavius or on BA, if so what are the links.

[LunarOrbit]

sticks said:

Q1. Who was it that twigged that the three stage approach would achieve this.

John Houbolt was one of the most vocal advocates for the lunar orbit rendezvous approach, but there were others.

Here's good site about the history of LOR:

oea.larc.nasa.gov/PAIS/Rendezvous.html

President John F. Kennedy's decision in 1961 to land a man on the moon "before the decade is out" meant that NASA had to move quickly to find the best method of accomplishing the journey. NASA gave serious consideration to three options: Initially, direct ascent; then, Earth-orbit rendezvous (EOR), and, finally, a darkhorse candidate, lunar-orbit rendezvous (LOR).

Direct ascent was basically the method that had been pictured in science fiction novels and Hollywood movies. A massive rocket the size of a battleship would be fired directly to the moon, land and then blast off for home directly from the lunar surface. The trip would be like that of a chartered bus, moving from point A to point B and back to A again in one brute of a vehicle.

Strong feelings existed within NASA in favor of direct ascent, largely because it meant the development of a proposed giant booster named the Nova. After the engineers made their calculations, however, NASA realized that any single big rocket that had to carry and lift all the fuel necessary for leaving the Earth's gravity, braking against the moon's gravity as well as leaving it, and braking back down into the Earth's gravity again, was clearly not a realistic option-especially if the mission was to be accomplished anywhere close to President Kennedy's timetable. The development of a rocket that mammoth would just take too long, and the expense would be enormous.

The demise of direct ascent led to a scrupulous evaluation of the second option: Earth-orbit rendezvous. The main idea of EOR was to launch two pieces into space independently using advanced Saturn rockets that were then in development; have the two pieces rendezvous and dock in Earth orbit; assemble, fuel, and detach a lunar mission vehicle from the modules that had joined up; and then proceed with that bolstered ship, exactly as in the direct flight mode, to the moon and back to Earth orbit. The advantage of EOR was that it required a pair of less powerful rockets that were already nearing the end of their development.

EOR enjoyed strong support inside of NASA, especially among those who recognized that selection of EOR as the mode for the Apollo mission would require the virtual construction of a space station, a platform in Earth orbit that could have many other uses, scientific and otherwise, beyond Apollo. For this reason, space station advocates like Dr. Wernher Von Braun and his associates at NASA's Marshall Space Flight Center in Huntsville, Alabama, favored EOR.

In the end NASA selected neither of the first two options: instead, it selected the third: lunar-orbit rendezvous.

The brainchild of a few true believers at the Langley Research Center who had been experimenting with the idea since 1959, the basic premise of LOR was to fire an assembly of three spacecraft into Earth orbit on top of a single powerful (three-stage) rocket.

[scooter]

Sticks, the Clavius site is basically one huge rebuttal of the hoax theory...BA also has a section. Very detailed, very easy to find both of them.

The HBs simply do not believe in doing any math...basically, if they can't understand it, then it must be impossible. Their arguments are easily answered by even the likes of me. I am not a rocket scientist, I'm a school bus driver with a couple of Masters courses in space systems engineering and space operations.

Really, basic rocket science isn't that hard to grasp, if you have half a mind...the arguments I see sometimes are incredible foolish...and the engineering wasn't a miracle, just evidence of what folks can do when they have the desire and means...

Dave

[sts60]

Supersonic flight was impossible using the technology of the early '40s. But somehow, it was accomplished in the later '40s. I'm confident that the U.S. practice was helped by captured German technology, and Nazi engineers.

Perhaps margamatix would like to tell us how supersonic flight never happened. Or that we should all hope it never happened because of some of the nasty characters who contributed to it.

Come to think of it, perhaps we're all just imagining we're reading this on a computer. After all, computers of today use solid-state technology - which of course was co-fathered by William Shockley, a Nobel Prize winner and notorious racist.

[JayUtah]

Q1. Who was it that twigged that the three stage approach would achieve this.

You mean the three Saturn stages or the LOR mission model?

Q2. Was Von Braun not involved with the space programme during the Apollo missions?

Of course. The Saturn V was a von Braun design. That's what makes this such a fabricated dilemma. Bart Sibrel wants you to take von Braun's word as gospel when he talks in 1953 about going to the moon. But then you're supposed to question von Braun 15 years later when he has discovered better means to do it.

Q3 The FAQ's on that site, have they been answered ppoint for point either here, Clavius or on BA, if so what are the links.

www.clavius.org/bibsibrel.html

[Sticks]

jayutah said:

Q1. Who was it that twigged that the three stage approach would achieve this.

You mean the three Saturn stages or the LOR mission model?

The three stage Saturn. (BTW who christened it Saturn and why?)

[Bob B.]

sticks said:

jayutah said:

Q1. Who was it that twigged that the three stage approach would achieve this.

You mean the three Saturn stages or the LOR mission model?

The three stage Saturn. (BTW who christened it Saturn and why?)

I doubt this can be attributed to any one person. The need to stage rockets to achieve higher velocities was well known and understood prior to the Saturn V. In general, it takes at least two stages to attain orbital velocities, and three stages to attain escape velocities. The three-stage configuration of the Saturn V was pretty much dictated by the delta-V it needed to produce.

[Sticks]

OK, I have another question about the rockets, but they go beyond the scope of this thread, so will need to start one in the Reality of Apollo section

[Sticks]

Incidentaly I had some other questions raised by BS (sounds like a good acronym for something else, which has for more use on the garden )

I need to move them to another thread as well, given this one is about the Saturn V rocket

[Al Johnston]

I think it wound up being called Saturn because the previous rocket design was called Jupiter, and Saturn was the next planet out...

[JayUtah]

"Modern" rockets begin even earlier than the 1960s. The 1950s missile designs are still the basis for many current launch vehicles...

Yes, my mistake. The Atlas design, for example, dates to the late 1950s.

Only the Atlas and its Centaur upper stage actually rely on internal pressure for structural strength...

I went overboard on balloon tanking, didn't I? Those vehicles must have their tanks pressurized. On other vehicles tank pressurization contributes to stiffness measurably, but doesn't require it in order to be structurally stable.

The V-2 was built according to the convential former-longeron method being used in airplanes. More modern designs are superfically similar to that arrangment -- ring-truss and skin-and-stringer -- but are significantly lighter than the V-2 structures. The V-2 had tanks inside the fuselage structure while in most modern designs the tank wall is the vehicle skin. The tanks are rigidly framed enough to stand on their own, and acquire additional stiffness through pressurization.

[Count Zero]

Here's what I don't understand:

-The structure needs more stiffness, so they pressurize the tank.
-The loads on the rocket increase as it accellerates; dynamic pressure builds as it goes supersonic, and the Gs increase as the mass decreases due to fuel consumption.
-As the fuel in the tanks is expended, doesn't this reduce the structural strength of the rocket, even as the loads increase? WTF?

[JayUtah]

The short answer is that ullage pressure is maintained either by the natural boiloff of propellant (in the cryogenic case), or the introduction of shunted exhaust gas into the top of the tank (in the noncryogenic case). But as Gwiz pointed out, only the older Atlas design is especially sensitive to that since it's the only one whose design specifically required pressurization stiffness as a component of the overall vehicle strength. Newer designs can do quite well without internal pressurization. In fact, in most modern designs the stiffness from internal pressure is considered an advantageous side effect; the static fuel pressure is maintained chiefly to increase the effectiveness of the fuel pumps.

Most of the load you describe is axial compression. Cylindrical shells are naturally very good in axial compression. The trick is to maintain the cylindrical shape. If you dimple on the side, it collapses. If you apply too much bending moment, it collapses. If it's thin (length/diameter ratio > 15), it buckles. If the cylindrical shape is maintained, you can have a safety factor as high as 5-10 compared to the expected loads.

Aerodynamic load peaks early and then falls off. By the time intertial loading becomes an issue, staging has altered the geometry of the vehicle and produced a shorter, fatter cylinder that is naturally less susceptible to deformational forces. Across the board, steering has to be considered. The inertial response to pitch and yaw maneuvers stresses the vehicle non-axially, requiring sufficient stiffness.

[Count Zero]

OK, so as the rocket pitches over and the fuel flows to the "down" side of the cylinder, is there a structural strength differential between the liquid-loaded "down" side of the cylinder and the gas-loaded "up" side? How much of a problem was this?

[PeterB]

...as the rocket pitches over and the fuel flows to the "down" side of the cylinder, is there a structural strength differential between the liquid-loaded "down" side of the cylinder and the gas-loaded "up" side?

Why will the fuel flow to the low side of the tank? Remember, the rocket is accelerating along its long axis. That alone will force the fuel to the bottom of the tank. It's the same principle which makes water stay in the bucket when you swing it over your head.