Real Saturn 5 thrust figures

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RodRocket

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Just started watching a long multi part documentary on the Apollo missions. Pretty neat so far but,

The Apollo 4 mission tested the stages of the Saturn 5 and it was mentioned that it had 7,500,000 lbs of thrust at lift off.

Anyone figure out what this would equal in our little hobby world?

What letter would that be if the scale goes far enough?

And how far would one have to stay back to keep a safe distance per Tripoli rules?

Just something to have a little fun with.

See ya,
Rod
 
Well I tried using that little program in thrustcurve.org to create a motor that approximates a shuttle SRB (which is not very strong compared to a Saturn V) and Openrocket can't simulate it at all...

As for distances, you have to stay probably at least several miles away. The sound from the blast alone will kill you, not to mention all the firey bits that comes later... if you stayed at HPR distances.
 
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The Saturn 5 was considered an 8Z under the letter clasification. Space shuttle SRB is 5Z

Greg
 
A little bit of trivia I recall

The viewing stands for the Apollo missions with the Saturn V were 3 miles away from the pad.

That distance was calculated as the furthest a 50 pound chunk would be thrown if it blew up on the pad....

Just watch out for them 40 pound chunks.... :wink:
 
The horse power equivalent is roughly as much as 16,000 10,000 HP top fuelers. Can you just imagine the sound out of that!! It's also the second loudest man made sound only next to an atomic explosion. POP, pssssss...
 
I have only seen the rocket in person, at Johnson Space Center in like 1991 or something when that area wasn't sealed off. That thing is easily the size (in diameter only) of an apartment building and as tall as a skyscraper when standing up. But they launched those things long before I was even born. I mean these days they seem to be launching probes and stuff with much smaller rocket than the Saturn V so I do wonder are they planning on launching men to Mars with those Delta III rocket?
 
I have only seen the rocket in person, at Johnson Space Center in like 1991 or something when that area wasn't sealed off. That thing is easily the size (in diameter only) of an apartment building and as tall as a skyscraper when standing up. But they launched those things long before I was even born. I mean these days they seem to be launching probes and stuff with much smaller rocket than the Saturn V so I do wonder are they planning on launching men to Mars with those Delta III rocket?
As I understand the problem, that's the problem ... We don't currently have any heavy lift launch vehicles. In terms of power, the Delta III is in the same league with the Shuttle, which had nowhere near the grunt of the Saturn V. The SLS is kind of the great hope in that arena.

It's been said before, though, in general, we're too risk-averse. It's going to be a long time, if ever, before anything gets "way out there" again.
:(
 
I have only seen the rocket in person, at Johnson Space Center in like 1991 or something when that area wasn't sealed off. That thing is easily the size (in diameter only) of an apartment building and as tall as a skyscraper when standing up. But they launched those things long before I was even born. I mean these days they seem to be launching probes and stuff with much smaller rocket than the Saturn V so I do wonder are they planning on launching men to Mars with those Delta III rocket?

No.

"Delta IV Heavy", not Delta III. And/or "Falcon Heavy".

Google them.
 
Just started watching a long multi part documentary on the Apollo missions. Pretty neat so far but,

The Apollo 4 mission tested the stages of the Saturn 5 and it was mentioned that it had 7,500,000 lbs of thrust at lift off.

Anyone figure out what this would equal in our little hobby world?

What letter would that be if the scale goes far enough?

And how far would one have to stay back to keep a safe distance per Tripoli rules?

Just something to have a little fun with.

See ya,
Rod

The Saturn V produces 7,653,854 lbs-force* (34,046, K-Newtons) at liftoff. Each engine is rated at 1,530,770.8 Lb/F. The center F-1 runs for 135.5 seconds** before being signaled to center engine cutoff. The remaining 4 outboards run for a total of 165 seconds***. That equates to 273,756,130.7 5,416,725,812 N-seconds, which is 63.2% 0.9% of an "AB" "AG" impulse motor. Beyond "Z" the impulse is prefixed with the letter "A", so the first class beyond "Z" is the "AA" class, then the next is "AB" class, and so forth (but cannot recall where I read that).

By way of comparison, the V-2 is a 51.9% "X" impulse motor (55,100 Lb/F rated thrust for 65 seconds,15,931,308.8 N-seconds).

The Mercury Redstone launch vehicle is a 35.8% "Z" impulse motor (78,000 Lb/F rated thrust for 215 seconds, 74,596,690.8 N-seconds).


Greg

* NASA Saturn V launch vehicle fact sheet.
** NASA First Stage Fact Sheet
*** Saturn V wiki, but the NASA First Stage Fact Sheet states the remaining outboards run until either the LOX or RP-1 (rocket-grade kerosene) sensors signal "tanks dry". 0.006 Seconds after outboard engines are signaled to "engine cutoff", a total of 8 retrorockets (2 each are hidden inside the fin fairings) are fired at first stage separation to help insure that there is no collision between the first stage and the rest of the stack.
 
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Also noticed just how much stuff was falling back to earth during the launch, must have been quite the chore to collect those parts back. Will be a fun watch, I was born in 68 so too young to remember anything, but always had the interest. Started watching this dvd set and when the narrator mentioned the thrust I thought it would be neat to compare to our rockets.

It's a metal tin box with Moon Race - The History of Apollo on the front. The 2 dvd set goes from the Apollo 4 test through the Apollo 17 and Soyuz missions.

CRG270013 Copyright 2010

www.allegro-music.com

Found it in the local dept store and got it on sale so I had to get it.

See ya,
Rod
 
most the third stage stuff probably hang around orbit just waiting to hit any spacecraft that dares to go there...
 
Also noticed just how much stuff was falling back to earth during the launch, must have been quite the chore to collect those parts back...

If you mean all of the white debris falling off of the rocket during the high-speed launch footage, that is ice. Thy cryogenics in the tanks (LOX in all 3 stages and LH2 in the second and third stage) were extremely cold and the condensation from the Florida humidity would freeze and form ice on the stack. In fact, the differential temperature from the ambient Florida air to the liquid hydrogen in the tanks was about 500 degrees F. Between 9 and 8 seconds before liftoff, the ignition sequence started for the F-1s. As they came up to pressure, they created a resonant frequency (vibrations) that is transmitted throughout the stack. At liftoff the stack also compresses a bit, so all of the ice begins to be broken off and it comes down almost like rain.

Greg
 
AB.....holy cow!!!

Would have loved to seen that motor beening tested!
 
I mean the hard parts, the first stage, spacer rings, panels. All this stuff gets ejected during each staging. Do the larger parts have recovery chutes? And I guess that these all fall into the ocean at estimated predetermined locations. There must be ships ready to recover as these parts touch down. The video may go into this on just what is reusable if anything.
 
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I mean the hard parts, the first stage, spacer rings, panels. All this stuff gets ejected during each staging. Do the larger parts have recovery chutes? And I guess that these all fall into the ocean at estimated predetermined locations. There must be ships ready to recover as these parts touch down. The video may go into this on just what is reusable if anything.

All of those parts were discarded. No recovery chutes, they just fell into the ocean and were destroyed.
 
The first stage fell into the Atlantic off shore from the Florida coast, the second stage would typically breakup over the Indian ocean and the third stage would, on a lunar mission, go into solar orbit or impact on the moon. The second stage on the Skylab launch made it to orbit and was the largest object in orbit for some time (by volume; the Skylab itself outweight it at 79 metric tons to 49) until it reentered in January 1975 over the Atlantic ocean.
 
The convention I've seen for motor sizes over Z is to just keep adding Z's.
A space shuttle segment alone is a 5Z.

So a Saturn V first stage engine would be roughly a ZZZZZZZZ330660000-P with around 5413585000 N*s of impulse
In other terms it has the impulse of 615 million C6-3s or 132,167 O8000s.
It also has the same average thrust as 55 million C6-3s or 57000 N5800s

The motor classification system gets a bit of a large range of motor sizes, considering the 8Z classification covers motors from 5 to 10 billion newton seconds.


If you are ever talking to kids about rockets these comparisons are great things to use, since most kids at least know what a C motor is roughly like.

Another good one is the Saturn V had enough thrust to lift almost 2000 minivans off the ground, or put 65 of them into space.
 
The convention is A, B, C,....., X, Y, Z --> AA, AB, AC, ...., AX, AY, AZ --> BA, BB, BC,...., BX, BY, BZ --> CA, CB, CC,.... etc.

Bob
 
The convention is A, B, C,....., X, Y, Z --> AA, AB, AC, ...., AX, AY, AZ --> BA, BB, BC,...., BX, BY, BZ --> CA, CB, CC,.... etc.

Bob
If you can provide official verification of some kind for that, see this Wikipedia entry:

https://en.wikipedia.org/wiki/Model_rocket_motor_classification

They simply reference this (although their link to it doesn't work):

https://www.tripoli.org/MotorImpulseClasses/tabid/152/Default.aspx

and then come up with their own Y and Z classes, then extrapolate with 2Z, 3Z, etc.

Not that this is really that important since model rocketry impulse classes probably aren't of much interest to NASA, ESA, etc., and even DIY HPR motor types will never get anywhere near the end of the "total impulse alphabet."
 
If you can provide official verification of some kind for that, see this Wikipedia entry:

https://en.wikipedia.org/wiki/Model_rocket_motor_classification

They simply reference this (although their link to it doesn't work):

https://www.tripoli.org/MotorImpulseClasses/tabid/152/Default.aspx

and then come up with their own Y and Z classes, then extrapolate with 2Z, 3Z, etc.

Not that this is really that important since model rocketry impulse classes probably aren't of much interest to NASA, ESA, etc., and even DIY HPR motor types will never get anywhere near the end of the "total impulse alphabet."

Yea I don't really see a point in recycling the alphabet, adding 8 Z's looks more impressive to most people than AH does. Plus by the time you get to CA sized motors your pretty much at the point of "That's no moon, that's a rocket engine!" size of rocket motors. So anything past 9 or 10Z is for most intents and purposes pretty much impossible with chemical rockets.

You might be able to get something larger than 10Z in Kerbal Space Program perhaps?
 
I think in the professional rocketry area engines are just listed by thrust (if liquid/hybrid, as total impulse can vary based on how much fuel is added to the tank, after all you don't list the total impulse of your car engine do you?), and for solid rocket motors it is listed by average thrust and total impulse. It's just that the alphabet system is easier for the average (non rocket scientist) people to gauge performance.
 
All of those parts were discarded. No recovery chutes, they just fell into the ocean and were destroyed.

Everyone thinks SpaceX is so innovative these days for wanting to recover their first stages. But the truth is, back in the day, Boeing actually had plans on the drawing board to do recovery of the S-IC, or first stage of the Saturn V.

These included designing a helicopter with rotor blades the diameter of a football field that could catch the stage as it was falling under parachute!

See this thread for a link to an article about that, as well as pages from a brochure with another recovery idea they were pitching. https://www.collectspace.com/ubb/Forum29/HTML/000880.html
 
Everyone thinks SpaceX is so innovative these days for wanting to recover their first stages. But the truth is, back in the day, Boeing actually had plans on the drawing board to do recovery of the S-IC, or first stage of the Saturn V.

These included designing a helicopter with rotor blades the diameter of a football field that could catch the stage as it was falling under parachute!

See this thread for a link to an article about that, as well as pages from a brochure with another recovery idea they were pitching. https://www.collectspace.com/ubb/Forum29/HTML/000880.html
All well and good, but few have performed an honest costing on the cost of actually recovering and rehabbing the hardware. When you do, you find out why most of the proposals never went beyond the paper stage.

There is an up front cost in recovering a booster and a fixed cost for the recovery infrastructure and a recurring cost for each unit recovered.

The extra mass required for booster recovery and extra propellant for the recovery mission reduces the payload capacity to orbit capacity by 30% (Space-X numbers not mine) so it raises the price of each launch by a minimum of the propellant cost not to mention the additional cost in materials and labor to make and transport a larger booster....

The cost of a Falcon-9 launch is ~$62M. That's the cost of the booster, propellant,and launch.

What is frequently forgotten is the fixed cost of the recovery system. Space-X has their floating recovery barge. It probably cost $10M-$20M to have it built and outfitted, and it needs to be brought out by a large manned tug, and maintained and repaired after each use, successful or unsuccessful.

Assuming a booster is successfully recovered it must be transported to a land based facility, inspected, repaired and requalified. Disassembly and reassembly is required. The only cost savings may be the manufacturing of the parts that can be reused, however all the old parts need to be inspected and requalified so what is the real savings. Certainly if you use all new parts, they are cleaned after manufacturing and are easy to QC. The recycled motor must be taken apart, cleaned, inspected, reassembled and tested. The taking apart must be cheaper than the cost to manufacture or reuse is a loose which was proven by the Shuttle program.

Where Space-X is different is that they ultimately want to launch from TX and fly the booster back to the launch site. If they can succeed, they may stand a chance of saving a few million per launch, if they recover each booster safely. I wish them well, but it will be difficult. If anyone can make it work, it's Space-X, but no one has yet to show a positive cash flow from a reusable launch system, including shuttle.

Bob
 
All well and good, but few have performed an honest costing on the cost of actually recovering and rehabbing the hardware. When you do, you find out why most of the proposals never went beyond the paper stage.

There is an up front cost in recovering a booster and a fixed cost for the recovery infrastructure and a recurring cost for each unit recovered.

The extra mass required for booster recovery and extra propellant for the recovery mission reduces the payload capacity to orbit capacity by 30% (Space-X numbers not mine) so it raises the price of each launch by a minimum of the propellant cost not to mention the additional cost in materials and labor to make and transport a larger booster....

The cost of a Falcon-9 launch is ~$62M. That's the cost of the booster, propellant,and launch.

What is frequently forgotten is the fixed cost of the recovery system. Space-X has their floating recovery barge. It probably cost $10M-$20M to have it built and outfitted, and it needs to be brought out by a large manned tug, and maintained and repaired after each use, successful or unsuccessful.

Assuming a booster is successfully recovered it must be transported to a land based facility, inspected, repaired and requalified. Disassembly and reassembly is required. The only cost savings may be the manufacturing of the parts that can be reused, however all the old parts need to be inspected and requalified so what is the real savings. Certainly if you use all new parts, they are cleaned after manufacturing and are easy to QC. The recycled motor must be taken apart, cleaned, inspected, reassembled and tested. The taking apart must be cheaper than the cost to manufacture or reuse is a loose which was proven by the Shuttle program.

Where Space-X is different is that they ultimately want to launch from TX and fly the booster back to the launch site. If they can succeed, they may stand a chance of saving a few million per launch, if they recover each booster safely. I wish them well, but it will be difficult. If anyone can make it work, it's Space-X, but no one has yet to show a positive cash flow from a reusable launch system, including shuttle.

Bob

Well don't forget ULA's recently announced Vulcan launch system, which has an arguably even more complex system for recovering just the engines from the first stage that involves various deployments of parachutes AND air capture of the engines via helicopter....

Not saying recovering rocket parts is easy OR cheap. But everyone (read: general public/media) always seems to forget the challenges and the cost, and are only awed by the wow factor.
 
All well and good, but few have performed an honest costing on the cost of actually recovering and rehabbing the hardware. When you do, you find out why most of the proposals never went beyond the paper stage.

There is an up front cost in recovering a booster and a fixed cost for the recovery infrastructure and a recurring cost for each unit recovered.

The extra mass required for booster recovery and extra propellant for the recovery mission reduces the payload capacity to orbit capacity by 30% (Space-X numbers not mine) so it raises the price of each launch by a minimum of the propellant cost not to mention the additional cost in materials and labor to make and transport a larger booster....

The cost of a Falcon-9 launch is ~$62M. That's the cost of the booster, propellant,and launch.

What is frequently forgotten is the fixed cost of the recovery system. Space-X has their floating recovery barge. It probably cost $10M-$20M to have it built and outfitted, and it needs to be brought out by a large manned tug, and maintained and repaired after each use, successful or unsuccessful.

Assuming a booster is successfully recovered it must be transported to a land based facility, inspected, repaired and requalified. Disassembly and reassembly is required. The only cost savings may be the manufacturing of the parts that can be reused, however all the old parts need to be inspected and requalified so what is the real savings. Certainly if you use all new parts, they are cleaned after manufacturing and are easy to QC. The recycled motor must be taken apart, cleaned, inspected, reassembled and tested. The taking apart must be cheaper than the cost to manufacture or reuse is a loose which was proven by the Shuttle program.

Where Space-X is different is that they ultimately want to launch from TX and fly the booster back to the launch site. If they can succeed, they may stand a chance of saving a few million per launch, if they recover each booster safely. I wish them well, but it will be difficult. If anyone can make it work, it's Space-X, but no one has yet to show a positive cash flow from a reusable launch system, including shuttle.

Bob

I think that SpaceX might be moving more towards reusability in the sense of commercial airliners than Space Shuttle style.

With the move toward methane fuel, coking would be reduced, thus possibly allowing them to fly more than once without refurbishment.

Remember that they explicitly are playing the long game. Falcon 9 reusability may not be a large net cost reduction, but it is also acting as a testbed for the BFR to be much more reusable.
 
A little bit of trivia I recall

The viewing stands for the Apollo missions with the Saturn V were 3 miles away from the pad.

That distance was calculated as the furthest a 50 pound chunk would be thrown if it blew up on the pad....

Just watch out for them 40 pound chunks.... :wink:

But, if you go by the TRA safety code, the published minimum safe distance for a complex research launch greater than O impulse is 2500 ft. :cool:
 
Well don't forget ULA's recently announced Vulcan launch system, which has an arguably even more complex system for recovering just the engines from the first stage that involves various deployments of parachutes AND air capture of the engines via helicopter.....
The Vulcan engine recovery system is far simpler than the Space-X whole booster recovery system. ULA is blowing away the cheap, big, and bulky propellant tank and only recovering the engine pod which is the expensive part of the booster. Aside from the ridiculous proposal to use a helicopter to pluck the engine pod in mid-air, the idea is not bad. If it works.
Not saying recovering rocket parts is easy OR cheap. But everyone (read: general public/media) always seems to forget the challenges and the cost, and are only awed by the wow factor.
This is a commercial launch system. None of the customers paying for the launch care about the WOW factor. All they care about is paying the lowest possible launch price. Period.

Any launch customer wants, and are only willing to pay, the minimum cost to get their payload into space. For decades there was no competition, and nearly unlimited funding, and thus no cost-cutting. With the decreasing number of launches, and foreign competition from the EU, Russia and China, the US launch industry essentially consolidated into 1 old-school launch company, ULA (Lockheed and Boeing) until Space-X proved they could do space launches for less money than ULA.

The DoD has already told ULA they will not pay the development cost for a new engine to replace the inexpensive and reliable Russian RD-180 engine. That's ULA's problem. That issue aside, the only reason to recover the booster (or engines) is economic, so the overall cost to the recover and rehab the engines must be less than the cost of using new hardware as the customer only cares about what they pay for the launch. The customer wants the lowest firm-fixed price launch cost so if that's obtained by reusing the engines, that's fine, but if it cost less just to use everything once, that's what will happen. And ultimately, the ULA price will have to drop to what Space-X charges if ULA wants commercial launches.

And that's going to be tough. Space-X is currently using LOX-Kerosene which is the cheapest high performance propellant available. ULA is planning to use LNG instead of Kerosene which requires a second cryogenic fueling station and therefore more expensive and hazardous. The specific impulse advantage of LOX/LNG is about 3% over LOX/Kerosene but Kerosene has a 40% density advantage over LNG so the fuel tankage is smaller and also not cryogenic so the LV is smaller, has a higher density specific impulse and is cheaper. The Vulcan system also relies on strap-on solids which are less efficient and more expensive then a liquid propellant whereas the Falcon-9 heavy simply adds 2 additional identical LOX/Kerosene booster sections with cross-feed plumbing. Overall a superior and smaller, less expensive launch system.....

Bob
 
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