I'm thinking a form of suspension too. That seems like the best bet for keeping the exterior of the egg at least from breaking. Not sure what would be best though...

I was thinking some sort of fluid or gel suspension system could do the trick...

Warren Musselman

Yes, green jello is an option, neutral buoyancy fluids such as mineral oil maybe salt water, etc, but I think it needs to be a spring loaded sled as well, maybe more. At least 2 time constants in the system for sure.
J

I will admit that the more you guys talk about this, the more I think about this challenge. I wasn't talking about jello necessarily, but something like a mineral oil filled payload bay. The egg will float in mineral oil (5W50 is what I'm thinking) and if done right, thrust will push it down in the oil, but the oil will slowly flow around the egg cushioning the impact shock of the fast burn motor.

By the way, I'm thinking we should do this like the Single Shot Sweepstakes - pick a single motor and use it as the core rule. The H999 is what I'm thinking... any comments?

Warren Musselman

I like it. Fastest H motor ever made, and not likely to be dethroned soon. Should give eggs a nice ride 😀

Note, however, that if the egg will float in mineral oil, it will not be pushed downwards when it lifts off. It will continue to float as the mineral oil is drawn down harder than the egg.

I'm surprised at you Chris - floatation only will occur at rest - the egg as a unit will sink under thrust. I was guessing it would float - ideally there will be neutral boyancy. I sense an experiment on whether eggs float in motor oil or mineral oil or water. I can see a payload bay lined with a plastic bag full of some vicous but not too viscous liquid or gel with the egg(s) floating in the fluid..

Another substance that comes to mind is KY Jelly...

So what is the point of this? Just flying without scrambling the egg doesn't seem to be enough... Should it be maximum altitude without scrambling the egg? Maximum parachute duration? Nearest landing to the pad or some kind of marker? Highest acceleration?

Warren Musselman

Highest acceleration would be fun. Possibly lightest weight at liftoff so an accelerometer would not be needed? This should equate to highest acceleration. As for being surprised at me - why? If the egg floats at 1g, it will float under any acceleration. Try it in the car sometime with a helium filled balloon. When you turn, the balloon leans INTO the turn, not because it is not feeling any inertia or centrifugal force, but rather because the air around it feels MORE centrifugal force. The egg will only sink in the liquid if it would have sunk naturally. In neutral buoyancy, it will not change its location purely from the acceleration - it will maintain its position. If the egg is positively buoyant, it will always be positively buoyant. Suddenly increasing the gravity would not change this, and from the egg's point of view, there is no difference between launching it on a rocket and suddenly increasing the gravity 10-100 times. If you don't think this is correct, please explain why - I would love to know if I'm wrong. However, all logic and physics that I know would imply that it would not sink in a liquid that it is positively buoyant in from a force acting on both the egg and the liquid.

You may be right... I'm just going with the common sense view that a solid object floating in a liquid will move within the liquid under acceleration.

Warren Musselman

Warren,

Green jello was a joke referring to my Utah days where it is considered one of the major food groups. But gel would not be a bad choice, and maybe part of a composite cushioning system.

Generally only if there is a differential in density, but as we have decided the fluid should be matched for density and incompressible. There is an exception in biology/medicine which applies in head trauma, but thats because it is more akin to a thin film than a fetus sitting in a big sac. So the brain gets banged around and more importantly ablated by having to traverse ridges. Now a salt water solution in a centrifuge will change over time but for .3sec punch not sure whether it matters whether oil or H20.

One obvious material would be yolk/egg white itself which has the advantage of adding to breakfast the next day. The problem with just one time constant IMO as Chris has alluded to is that the yolk is gonna get slammed down--again think density gradient centrifuge. Here is where I think a sled on the right suspension might just take enough edge off liftoff, and the jerk accompanying burnout.

IMO, highest altitude, 2 eggs, and no yolk breakage. If everyones yolks get popped, highest altitude no shell breakage.
J

Personally I think we need a test flight before we determine the final rules for the contest... I want to see what an "average" rocket with an H999 does to an egg yolk.

Warren

Well given that the yolk can be broken with a quick jerk or two in your hand, I believe its a foregone conclusion that it will be broken but who knows. I'm all for a test flight 🙂 Then decide the rules, I do like the idea of 2 eggs for sure.
J

all i have to say is tempur pedic! its what astronauts use in the back of their chairs... that can easlly take many G's we also used to use pantyhose as a net of sorts, by putting the egg inside the hose the strech the hose like its supspended in the middle, Id like to enter this, what is the motor casing needed for warp 9? I have 29/180 and 29/240.

🙄 of course my luck ill burn through another 29 MM case (ive burned through 3 29mm motor casings now 2-180's and 1-120 2 of which were redline motors used... hmm? 🙄 this is getting kinda rediculos!

I think you guys are nuts, which is why I like you guys. This sounds great, and leads to a lot of experimenting. Very nice. 🙂

the temper pedic is an amazing material--actually over the summer I got to try one in a motel in GJ. Nice ride, slept like the dead and awoke w/o the usual backache. The ads are even more impressive with a fat guy jumping up and down on the bed while a glass of wine a few feet away is undisturbed. But the astronauts sustain what 6 gees? This poor egg will have to survive maybe 8 times that.

Your point is right on, tho, Dr Sutter, IMO. The foam you mention is visco-elastic material which both has a spring action and a damping action. I think thats whats needed here.
John S

I think the egg needs to be suspended in oil with about a mm or less space around the egg. The egg will float on the oil and when thrust hits, it will sink into the oil like the piston in a shock absorber with the oil squeezing past the egg into the forward part of the chamber. I'd definitely go with a thinner oil to start with... say extra virgin olive oil... and maybe work up to 20W50 if need be. Worst case you can use 90W hypoid gear oil.

Warren

I maintain that the egg would not sink if it began floating.

On the other hand, if an oil could be found where the egg was basically neutrally buoyant, the force would be spread over the entirety of the eggshell, and it would work fine. A liquid suspension would make the egg feel essentially no force, other than the yolk and white being smashed around. If it could be worked out, that would be the way to do it.