Help me gas dynamic stabilization, you are my only hope!

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"We can rebuild him. We have the technology. We can make him better than he was. Better, stronger, faster."
 
"We can rebuild him. We have the technology. We can make him better than he was. Better, stronger, faster."

That would cost SIX MILLION in 1972 dollars! Maybe just hack off the burned bits, take some nose weight off and stick in a new motor! This one is kinda like the bionic dog Max, if things go bad you can just put it down.
 
In a continuation of my hijacking of your post, I offer a video of the flight of my Inductor on an F35. I say it was stable most of the way up, which seems to show this does work as long as you have your rocket specs and mass flow dialed in. Hot off the presses:

[video=youtube;1h527geL8JM]https://www.youtube.com/watch?v=1h527geL8JM[/video]
 
Very cool. I had the flight card ready to go but the wind picked up today and the launch ended due to weather. No nozzles, no nose weight. Maybe the next launch in a week at a neighboring club, or at worst two weeks at CRASH. Need to get the B 58 up again, it has been loaded since spring.
 
My reworked Saturn so won't go up until September. The second one might be ready by then too. I had wanted to get one more flight on the first before finalizing the second, but there is a good chance build fever will take over.
 
I talked to Dean Black this past Friday at HellFire-20 about the induction rocket. I confessed that I had trouble understanding the equations. (I would need to go back and look at the paper again more closely.) He said that William Cook has a good grasp of the theory. Dean stressed several times that for a fin-less rocket (without induction) at an angle of attack the CP is very far forward on the rocket body close to the nose.
 
While I can follow the equations, I really can't apply them to a design. I basically just followed his latest reference design. The same way I design monocopters ;)
 
I might add that Dean no longer follows anything on the internet, so that explains why he is so hard to contact. I don't think he has a computer anymore. I believe that he lives in the same town as I do.
 
Good to know. I was worried when he suddenly went dark. If you see him, please fill him in on our efforts.
 
Dean found my related blog post and reports there were two HPR induction rockets at Hellfire and he will pass along links to any flight videos that emerge.
 
If he sends any info, I'll share it here for sure. He said he wasn't present when the rockets flew but will be on the lookout for documentation.
 
The new club rules just came down for sunny and dry Summer flying. Looks like Saturday is out for a GDS test flight. Maybe early September at Tripoli.

My personal interpretations in parenthesis.()

Summer launch restrictions:
No flights in greater than 10 mph winds.
No flights that have the potential to glide. (No oddrocs! NO COSMOS MARINERS - EVER!)
No questionable clusters or staging. (No oddrocs!)
No heads up flights. (No oddrocs!)
No first flights unless a proven design and/or built per manuf. instructions. (No oddrocs!)

Time to get out the Estes Leviathan, it just looks safe and can never start a fire. It is a hard knocks life for the oddroc flyer. Now all I can hope for are gray, snow covered and bitterly cold days. Happy days they will be. All the leaves have fallen and the skies are gray. . . :)
 
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Yeah, unfortunately those gray, snow covered and bitterly cold days areally often windy as well:wink:
 
Well, my NAR club allowed the Saturn V to fly prior to the scouts arriving. It headed up fast and straight...and then took a hard right. It didn't wobble during boost this time nor did it tumble during coast. The lack of tumbling ensured that it landed in the >50' trees. So, this does seem to confirm that GDS rockets should NOT have ducts ahead of the CG. But it leaves the question about why it went cruise missile. A video of the best part is here. I now have no idea what I'm going to do with the new version.
 
Well, my NAR club allowed the Saturn V to fly prior to the scouts arriving. It headed up fast and straight...and then took a hard right. It didn't wobble during boost this time nor did it tumble during coast. The lack of tumbling ensured that it landed in the >50' trees. So, this does seem to confirm that GDS rockets should NOT have ducts ahead of the CG. But it leaves the question about why it went cruise missile. A video of the best part is here. I now have no idea what I'm going to do with the new version.

Great report! I also was, after some debate, able to launch my GDS rocket at the club as the last launch of the day with fire crew. Report to follow once everything is uploaded and works.
 
GDS crash 2.jpgGDS crash 1.jpgGDS crash 3.jpg

I lowered the CG to just below the bottom end of the top launch lug with less nose weight and a revised top section. Used a standard rod, the wind about the same as the first launch. On the edge of stability it coned on the way up, was OK through out the cost and recovered nicely. Hopefully my video will down load from my phancy phone. Flew about like a poorly built scout rocket, or a highly boat tailed sci fi rocket, or scale V2 on the edge. Thanks to my fire crew. The less than straight flight caused a good deal of burn to the second ring. Is this GDS at work? Or is it just less nose weight and a shorter rod?
 
What motor did you use this time? It certainly did get toasty. Sound's like you had reasonable success, whether due to GDS or not. Still not sure if GDS action will occur with those multiple rings.

I had wanted to use something with a longer burn than the F44 but never got around to acquiring one. An F15 might have been next for me had it recovered. My new one is bigger and will get a G-something. But, I don't just want a bigger clone so I have to replan.
 
What motor did you use this time? It certainly did get toasty. Sound's like you had reasonable success, whether due to GDS or not. Still not sure if GDS action will occur with those multiple rings.

I had wanted to use something with a longer burn than the F44 but never got around to acquiring one. An F15 might have been next for me had it recovered. My new one is bigger and will get a G-something. But, I don't just want a bigger clone so I have to replan.

E9 4.
 
Yeah, it looks fine to me. Gives you a good sense of the flight profile.
 
Maybe time to close up those gaps for more GDS action, I can take the burn! I don't know how much more those silly ring fins can take. Maybe better GDS rocket science will help out with getting a pad assignment as this one might be close to going on the Commissar's black list. Must have a better flight!
 
Time to buckle down for some serious GDS action. So last night after the Top Gear rerun and before bedtime I modified the rocket once again to create the Gas Dynamic Stabilized Model III, or what I now call the GDSM III. Having added a bit of weight to the hind end I utilized the heavier nose cone from the Wack Wocket to move the CG up to about a quarter way up the top launch lug.



GDS 3.jpgGDS 3 2.jpg
 
Holy holey induction tube Batman!

My latest thought on mine is to add a smaller, internal tube that resembles a Jetex augmenter tube.
 
Well the Saturn V, SA-667 will, for better or worse, be ready for a September launch. This one is 3.1" dia vs. 2.875", features the LES, and has an internal augmenter tube. You can see the bellmouth in the photo. These were shown to increase thrust on Jetex motors but am not convinced that will apply here. I also don't know what this will do to any GDS action. I'd say there is only one way to find out but there is so much going on here that success won't prove that the augmenter or GDS worked. Similarly, failure could come from many sources. This is bad science...:y:

20880783735_0f79d98bda_z.jpg
 
Well the Saturn V, SA-667 will, for better or worse, be ready for a September launch. This one is 3.1" dia vs. 2.875", features the LES, and has an internal augmenter tube. You can see the bellmouth in the photo. These were shown to increase thrust on Jetex motors but am not convinced that will apply here. I also don't know what this will do to any GDS action. I'd say there is only one way to find out but there is so much going on here that success won't prove that the augmenter or GDS worked. Similarly, failure could come from many sources. This is bad science...:y:

View attachment 270760

But it really looks cool! And with the motor up high you are going to get maximum performance! Good bye to NO GOOD, STINKING, PERFORMANCE ROBBING NOSE WEIGHT! Goodbye fins and launch rod. GDS will do the trick!
 
Just talked to my rocket scientist source over at United Launch Alliance and he is watching this GDS stuff.

Will have to get some secret intel on the innards of that Saturn V 1st stage. Internal augmenter tubes, air induction scoops, wow. We will have to watch out for Red spies and SPECTRE agents. Nose weight will be liquid, shaken, not stirred during the flight.
 
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