Largest scale model rocket ever built to launch 25 April

[Eclipse]

http://www.rocketryplanet.com/content/view/2829/30/

[PlaneFlyr]

Awesome!  I want one.

[NIN]

Thats awesome. Unfortunately, I predict failure.  Spectacular failure. 

[jimmydeanno]

^It looks more viable than anything N. Korea's put out... 

[notaNCO forever]

^It looks more viable than anything N. Korea's put out... 

:clap:

[Eclipse]

Thats awesome. Unfortunately, I predict failure.  Spectacular failure. 

Ditto - my uneducated guess is that one of the reasons the Saturn was multi-stage was that pushing all that
weight from the bottom meant it was top-heavy and prone to tumble, especially in thinner atmosphere, though obviously
this won't get that high...

Can't wait to see the vids, though!

[davidsinn]

Thats awesome. Unfortunately, I predict failure.  Spectacular failure. 

Ditto - my uneducated guess is that one of the reasons the Saturn was multi-stage was that pushing all that
weight from the bottom meant it was top-heavy and prone to tumble, especially in thinner atmosphere, though obviously
this won't get that high...

Can't wait to see the vids, though!

Actually Major you want a rocket to be top heavy. It adds stability. The reason it's multistage is the reduce the dead weight carried to orbit. Also the SIC(bottom stage) burned a different fuel than the SII and SIVB to give it more raw thrust to get off the ground but had a less efficient fuel burn.

[SJFedor]

I predict something worthy of being on failblog.org.

[sardak]

Actually Major you want a rocket to be top heavy.

Correct. It's easier to steer a top heavy rocket. Early in my career, the concept was explained by balancing a household broom. With the brush end up, and the end of the handle in your hand, it takes little hand motion to move the top of the broom. If the heavy end of the broom is in your hand, it takes much more effort to move the end of the handle, and is harder to control where the top end goes. The basic control concepts are the moment arm and inertia.

As for mulit-stage:
From the NASA History Office, "Stages to Saturn, A Technological History of the Apollo/Saturn Launch Vehicles."
http://history.nasa.gov/SP-4206/sp4206.htm

Chapter 1 para 4
The intricacies of a successful lunar mission dictated a multiphased operation, and the Saturn V was a multistage rocket. Early plans for the moon rocket included proposals for a comparatively simple "one-shot" vehicle in the form of a single- stage rocket. For all the attraction of the basic simplicity of a single-stage rocket as compared with a multistage vehicle, designers finally discarded it.

The single-stage concept would have required a rocket of great girth and structural strength to carry all the required propellants. As a single-stage vehicle climbed into space, a considerable weight penalty developed because all the weight of the empty tankage had to be carried along.

This weight penalty severely limited the size of the payload- in this case, a manned spacecraft. The multistage design allowed the first stage, with its big booster engines, to drop off once its rocket propellants were depleted.

The second stage was more efficient because it had relatively less weight to push further into the planned trajectory, and it benefited from the accelerative forces imparted to it by the first stage.

By the same token, the third stage had an even lighter weight and an even higher acceleration. In addition, the multistage approach permitted the use of special high-energy fuels in the upper stages. These considerations played a large role in the development of the Saturn V as a three-stage launch vehicle.

The multi-stage concept for rockets is still the design of choice.

Mike

[Major Lord]

I thought his arranging of the rocket motors in a rectangular pattern was interesting. I would have expected a coaxial arrangement. How do they guarantee that all the motors will ignite simultaneously? One motor out of phase would cause a rather dramatic course alteration I would think. Its very cool though. I think he should carry a sky diver......

Major Lord

[SilverEagle2]

How do they guarantee that all the motors will ignite simultaneously?

We can't. But we can sure try.

I stay away from cluster motor designs for this reason.

Not to mention that I like large diameter, single motor fire trails better.

I am excited to see this launch as a fellow HPR hobbyist.

Really big burn

[freeflight]

I guess this means I need to work on my Estes Saturns

[Pingree1492]

[...]  How do they guarantee that all the motors will ignite simultaneously? One motor out of phase would cause a rather dramatic course alteration I would think. [...]

Which is exactly why the Saturn V rocket worked, and the Soviet Moon Rocket (the N-1) was a spectacular failure.  The Saturn V had only 5 engines in its first stage, each producing 1.5 million pounds of thrust.  The N-1 had 30 engines, each producing "only" about 306,000 pounds of thrust. 

In the N-1's 4 separate launches, the longest flight achieved was for 107 seconds before failure.

Hopefully, these guys have a great launch on Saturday!

[AlphaSigOU]

I thought his arranging of the rocket motors in a rectangular pattern was interesting. I would have expected a coaxial arrangement. How do they guarantee that all the motors will ignite simultaneously? One motor out of phase would cause a rather dramatic course alteration I would think. Its very cool though. I think he should carry a sky diver......

Very carefully, of course. As one who once flew competition model rocketry and worked in the industry the technology has advanced enough that a carefully designed cluster ignition system and igniters will light up that humongous Roman candle. Otherwise, that gigantic Saturn V is going to wind up doing the world's largest landshark impression.

The builder has erred on the side of caution: the fins on the Saturn V model are about 25-30% oversize from true scale, and I wouldn't be surprised if additional nose weight was added to improve the CG-CP relationship. (True-scale Saturns are marginally stable to fly unless in calm wind conditions; it's not unusual for additional noseweight or clear plastic fin extensions to be added.)

For the rabid Saturn V aficionado (like me  ), note that the configuration is correct for the unmanned Apollo 4 launch. There are eight ullage rocket fairings placed on the S-IC/S-II interstage; this configuration only flew on Apollos 4 and 6. The ullage rockets were reduced to 4 for the flights of Apollos 8 through 14 and removed completely for Apollos 15-17 and Skylab 1. Most NASA stock footage of a Saturn V launch is from the launch of Apollo 4 and 6, especially the spectacular sight of staging.

The real Saturn V did suffer from engine malfunctions; two J-2s on the S-II stage failed during launch of Apollo 6, but the instrument unit corrected the malfunction by burning the remaining engines longer. Had the launch been manned, the flight would have been aborted. The center engine of the S-II failed during the launch of Apollo 13 but again the remaining engines compensated by burning longer.

[AlphaSigOU]

Actually Major you want a rocket to be top heavy. It adds stability. The reason it's multistage is the reduce the dead weight carried to orbit. Also the SIC(bottom stage) burned a different fuel than the SII and SIVB to give it more raw thrust to get off the ground but had a less efficient fuel burn.

RP-1 (Rocket Propellant 1 - highly refined kerosene (Jet-A for you pilots out there  ) and LOX (liquid oxygen) for the S-IC; LH2 (liquid hydrogen) and LOX for the S-II and S-IVB. The CSM and LM used hypergolics.

The documentary film collection The Mighty Saturns has camera footage of the interior of the S-IC LOX tank draining its propellants - it's amazing to see how quickly the LOX gets sucked down.

[fyrfitrmedic]

[...]  How do they guarantee that all the motors will ignite simultaneously? One motor out of phase would cause a rather dramatic course alteration I would think. [...]

Which is exactly why the Saturn V rocket worked, and the Soviet Moon Rocket (the N-1) was a spectacular failure.  The Saturn V had only 5 engines in its first stage, each producing 1.5 million pounds of thrust.  The N-1 had 30 engines, each producing "only" about 306,000 pounds of thrust. 

In the N-1's 4 separate launches, the longest flight achieved was for 107 seconds before failure.

Hopefully, these guys have a great launch on Saturday!

Didn't the Russians go with so many engines because of an inability to work out "pogo effect" issues? I seem to remember hearing that...

[AlphaSigOU]

Didn't the Russians go with so many engines because of an inability to work out "pogo effect" issues? I seem to remember hearing that...

They didn't have the materials or technology available at the time for very large rocket engines. If I remember correctly the Russkie R-7 rocket has five combustion chambers but four nozzles (and associated verniers) in each strap-on booster and core. The Saturn V F-1 engine suffered through severe combustion instability problems (in other words it blew itself up) until they were solved by reworking the injector plate design.

[BuckeyeDEJ]

I saw the title of this thread and wondered, "if it's the largest scale rocket ever built, is it 1:1?"

Hey, you never know.

Now back to your regularly scheduled thread.

[PHall]

We have some pretty big rockets out here in California at ROSTOCK out in the Mojave Desert.
We have the added fun of having the guys from Cal Tech and the rocketry club from JPL who bring out the really neat toys.

Which is one of the reasons we have a 40,000 foot altitude limit for a couple of hours on Saturday.

Those big suckers need some room to play!

[sardak]

Here is more info on the rocket and the launch site:

The rocket's homepage:
http://www.rocketsmagazine.com/saturn-v-project/main.html

The launch site in Maryland:
http://www.mdrocketry.org/Launches/HiggsFarm.html#SiteInfo

Mike

[sardak]

Successfully launched and recovered today!  :clap:

Here is the first video I've found, which unfortunately doesn't follow the rocket after it leaves the launch pad. The launch is nothing like a real Saturn. The thrust to weight ratio of this launch was much higher so it "rockets" off the pad (sorry, I couldn't resist). The video captures the rocket again during its descent.

http://tinyurl.com/crym6f

Here's a second video that captures the entire flight. The rocket landed vertically, engine end down, just like the launch configuration.

http://www.youtube.com/watch?v=U_bIanFc_yI

Mike

[AlphaSigOU]

Outstanding! Cluster's Last Stand works! 

[DC]

Here's a better, closer view. You can see the rocket clearly all the way from launch to recovery. There is also a slow-mo replay of the launch at the end.

http://www.youtube.com/watch?v=bj4lj6YSwzg&NR=1

[Major Lord]

Man, launching "D" engines is just not going to be fun anymore after that!  It seems all the really insane people do the coolest aerospace stuff!

Major Lord

[AlphaSigOU]

Man, launching "D" engines is just not going to be fun anymore after that!  It seems all the really insane people do the coolest aerospace stuff!

With LOTS of money to burn! 

Granted, the motors and propellant (I'm assuming they were reloadables) were probably donated but high-power rocketry can quickly spiral out of control in construction and powerplant costs. Awesome wow factor, though!

Scale flight point minus: other than the clouds of steam and partially burned fuel at ground level during liftoff, a Saturn V launch is relatively smokeless (as are all liquid-fueled launches). Congrats to Steve Eve and a dream come true!

[Gunner C]

Zowie!  Wish I could have been there!  Anyone know if he's going to upgrade the system (staging, etc)?

[AlphaSigOU]

Zowie!  Wish I could have been there!  Anyone know if he's going to upgrade the system (staging, etc)?

Don't know, but staging presents some serious challenges to the model and high-power rocketeer.

The ones who really get crafty with live staging on flying scale models are the guys on the S5/S8 (FAI class for scale altitude and scale spacemodeling) teams. The rules essentially rule out most rockets except the Russian Soyuz, Saturn IB/V, Ariane and Space Shuttle. And the Russkies will do everything possible to make their model with operational staging. It's not unusual to see a dozen chutes in the air, and all must land with minimal or no damage.

[Eclipse]

A success!  I'm not a rocket , but it sure looked pretty - it also "landed" standing up!

http://www.youtube.com/watch?v=bj4lj6YSwzg&NR=1

[SilverEagle2]

What was cool was how he separated the beast. An automotive airbag trggered by his altimeter.

Gave me a ton of ideas for my own large project in the planning stages.

[SJFedor]

Wow. I'm pretty impressed. I expected to be watching that video on failblog. Great job!

[PHall]

That thing probably would have triggered the Missile Warning System on many military aircraft, with the resulting release of flares and chaff too!

[SJFedor]

Anyone know how many hoops he had to go through to get permission to do this? From just eyeballing a map, Price MD is inside the ADIZ.

[CadetProgramGuy]

I'm sure it is just the standard FAA Waiver for Model Rocketry.  If I look hard enough I could find it, but it is 245am......

[DC]

Yeah, as big an powerful as it was, it was only designed to go to 3 - 4,000', which isn't too far out of the normal model rocket altitude envelope for multi-stage 18mm and 24mm rockets.

[SilverEagle2]

He probably flew under his HPR clubs standard FAA waiver. Given that the attitude it reached it was a matter of just advising the FAA of the launch window.

Here in Utah we have a standing waiver to 10,000 AGL for all of our scheduled launch days. If they change, we just inform the FAA in advance and they activate it for us.

Now for Hellfire out on the Salt Flats...we also get the ability to call in 50,000 AGL requests and the FAA grants us 15 minute launch windows if workload permits.

They are pretty good to us here.

I am sure the club had a 10,000 AGL waiver in place for that day and he was GTG from there.

Was a sweet launch.

[SJFedor]

He probably flew under his HPR clubs standard FAA waiver. Given that the attitude it reached it was a matter of just advising the FAA of the launch window.

Here in Utah we have a standing waiver to 10,000 AGL for all of our scheduled launch days. If they change, we just inform the FAA in advance and they activate it for us.

Now for Hellfire out on the Salt Flats...we also get the ability to call in 50,000 AGL requests and the FAA grants us 15 minute launch windows if workload permits.

They are pretty good to us here.

I am sure the club had a 10,000 AGL waiver in place for that day and he was GTG from there.

Was a sweet launch.

Yeah, the thing is, I would think the FAA and DHS wouldn't be too keen about anyone launching rockets inside the ADIZ. I'm wondering how they got around that. Launching something out in Utah is a lot different then launching in suburban MD.

Edit: Looks like Price is about 2 miles outside the 30nm ring for DC. So maybe it wasn't an issue.

[sardak]

Per the launch site website at Higgs Farm, MD
# Our waiver is for 17,000' MSL, 16,900' AGL.
# The waiver will run from 9am to 6pm Saturday & Sunday.

Post launch photos and flight data at
http://www.rocketsmagazine.com/saturn-v-project/
There were several "flight recorders" and a GPS which registered a max acceleration of  6.2 to 7.3 g's, max speed of 300+ MPH and max altitude of almost 4700 ft.

Mike

[Gunner C]

Is he going to fly it again?

[NIN]

Is he going to fly it again?

With your Apollo capsule signed by Walt Cunningham, Al Bean & Homer Hickam, I'd put the darn thing in a display case in my living room and be done with it!!

[SilverEagle2]

Launching something out in Utah is a lot different then launching in suburban MD.

Not if the appropriate waiver is in place. We have the same rules as MD.

Not to mention we launch at our regular site we are within 3 miles of a National Security Restriction and when on the Flats, into a very active restricted area.

So in hindsight, you're right...very different. 

[C/MSgt Lunsford]

Nice launch and glade it went well. Congrats.

[RiverAux]

If you look closely at the video there were some folks standing REALLY close to that when it was launched.  Perhaps I watched the NEC talk to much about safety yesterday, but they might have benefited from a little larger no-go zone around the rocket. 

[AlphaSigOU]

If you look closely at the video there were some folks standing REALLY close to that when it was launched.  Perhaps I watched the NEC talk to much about safety yesterday, but they might have benefited from a little larger no-go zone around the rocket.

That was probably the launch/recovery crew, but then the camera does have a way of making things closer than they actually were. It was a 'heads up launch' in which everyone is required to be standing so they can make a quick getaway if the launch went FUBAR.