15 inch nose cone at local army surplus

[Donaldgranger]

really its 15" by about 3 and a half feet long made of fiberglass its heavy its big any good for a big rocket or no! the guy wants 45 dollars for it!

 

[CarVac]

really its 15" by about 3 and a half feet long made of fiberglass its heavy its big any good for a big rocket or no! the guy wants 45 dollars for it!

Put fins on it and fly it!

No body tubes necessary.

 

[bandman444]

really its 15" by about 3 and a half feet long made of fiberglass its heavy its big any good for a big rocket or no! the guy wants 45 dollars for it!

Post a picture. I wanna see.

 

[Donaldgranger]

ok but i will have to go back to store!

 

[bandman444]

You will just have to get it!


Stop by your construction supply store and test fit some sonotube. $5-7/ft grab 12ft and build something really cool.

I'm just a motivator.

 

[4kids49]

Wow 15 inches! This might be up CWBullets alley.

 

[JPVegh]

$45 bucks and you didn't buy it? Sounds like a bargain to me.

 

[Coop]

$45? I'd have been ALL over that.


Later!

--Coop

 

[fyrwrxz]

45 bucks???-crap- my stupid mailbox cost more than that! Whut's wrong wid you ,Wilis??? Even if you never fly it- heck you got a real nosecone!!!

 

[TopRamen]

I'm with the "Buy it and Fly it" Folks.

 

[jimzcatz]

How sure are you on measurements. I see cones like this alot and they are usually from an AGM-78 Standard Arm. But of courseI could be wrong. Does it hae a shoulder, or just flush?

 

[Donaldgranger]

no shoulder just a hollow fiberglass cone but i thought something could be made to give it a shoulder??

 

[Handeman]

no shoulder just a hollow fiberglass cone but i thought something could be made to give it a shoulder??

I'm with the buy and fly. If you build the rocket with a 98mm or larger MMT and keep the whole thing below 125 lbs fight ready, you should be able to do L2 cert with a 75/5120 L2200G. That would be a very cool cert flight! Then when you get it back, stuff a M in it and do L3 right away!

 

[cwbullet]

No doubt about it. Under 100 and it would be in my living room.

 

[Frozenferrari]

I'm with the buy and fly. If you build the rocket with a 98mm or larger MMT and keep the whole thing below 125 lbs fight ready, you should be able to do L2 cert with a 75/5120 L2200G. That would be a very cool cert flight! Then when you get it back, stuff a M in it and do L3 right away!

If im not mistaken, you must build a new rocket for L3? I thought it was against the rules to use a rocket you already had for L3...
Thats what I had been told before...

Dang 15" dia thats crazy. I wanna see a pic!

 

[MasonH]

If im not mistaken, you must build a new rocket for L3? I thought it was against the rules to use a rocket you already had for L3...
Thats what I had been told before...

Dang 15" dia thats crazy. I wanna see a pic!

My understanding from talking with my L3CC was that as long as the building of the rocket is properly documented, you can use the same rocket for an L2 AND L3 flight, but you have to complete all the proper paperwork AFTER you get your L2. The L3 Cert Package cannot be submitted until after the L2 flight, methinks.

 

[tsai]

I think it depends on NAR vs TRA. For NAR, you have to get the design package/construction plans approved before you begin construction. (See section 3.2)

Since you can't actually start the process until you are L2, that prohibits using the same rocket for both L2 and L3.

Cheers,
- Ken

My understanding from talking with my L3CC was that as long as the building of the rocket is properly documented, you can use the same rocket for an L2 AND L3 flight, but you have to complete all the proper paperwork AFTER you get your L2. The L3 Cert Package cannot be submitted until after the L2 flight, methinks.

 

[MasonH]

I think it depends on NAR vs TRA. For NAR, you have to get the design package/construction plans approved before you begin construction. (See section 3.2)

Since you can't actually start the process until you are L2, that prohibits using the same rocket for both L2 and L3.

Cheers,
- Ken

True, I have not looked into TRA cert requirements. What I posted was relevant only to the NAR.

 

[Handeman]

If im not mistaken, you must build a new rocket for L3? I thought it was against the rules to use a rocket you already had for L3...
Thats what I had been told before...

Dang 15" dia thats crazy. I wanna see a pic!

I'm not sure if that would work or not. Can you work with Tripoli TAPs to build a L3 rocket and use it for L2 cert also? Or do you have to be L2 already to begin the L3 process with the TAPs?

 

[3stoogesrocketry]

A member of our club used a 7.5 inch fatboy for all three cert flights . Contact your taps before doing anything.

Eric

 

[Fuddrucker]

Here is one that is about 7 feet tall and about 20+ inches in dia. My son saw it in Idaho at a surplus store.

...Fudd

 

[dh4664dh]

Use the nosecone as the entire rocket. Cut slots in the nosecone lower section and put a 6 inch (or larger) tube inside the nosecone. This tube becomes the airframe. Attach the root of the fins to the outside of this tube, along with a couple of centering rings and a top bulk plate to connect to the recovery harness. Then create a separate motor mount which slips into the tube only as far as being flush with the bottom so you can use rear ejection for the recovery.

It might be a good idea to enable a way to put weight at the top of the nosecone in case you need to add it.

There is enough space around the base for additional motor tubes which can be glued in, ala air starts. Or put in an av-bay and use dual deploy. The possibilities are endless!

 

[Onebadhawk]

Pic's ,,, Pic,s ,,, Pic's,,,,

Teddy

 

[dh4664dh]

I was not sure if onebadhawk wanted pictures of what I was proposing for a design, so I went ahead and defined the design in RocSim, both with a single 98mm motor and then with a single 98mm motor plus three 75mm motors. The designs are shown below.

I then simulated the designs:
- A single 98mm CTI 1450 Classic >>> over 7700 feet
- A single 98mm CTI 1450 Classic and three 75mm K510 Classic >>> over 14000 feet

 

[CarVac]

I was not sure if onebadhawk wanted pictures of what I was proposing for a design, so I went ahead and defined the design in RocSim, both with a single 98mm motor and then with a single 98mm motor plus three 75mm motors. The designs are shown below.

I then simulated the designs:
- A single 98mm CTI 1450 Classic >>> over 7700 feet
- A single 98mm CTI 1450 Classic and three 75mm K510 Classic >>> over 14000 feet

View attachment 145816

What's the CG with motors installed?

You may not need THAT much stability, especially since it'll have a huge base.

 

[Onebadhawk]

I wanted to see pics of the nose cone,,,,
but the design you came up with is very cool.....
I wasn't aware that a larger base increased stability......
The diameter looks so large that it would decrease stability.......

Teddy

 

[DizWolf]

I wanted to see pics of the nose cone,,,,
but the design you came up with is very cool.....
I wasn't aware that a larger base increased stability......
The diameter looks so large that it would decrease stability.......

Teddy

Base drag is how saucers go (mostly) straight up without fins. Mini maggs and other stubbie rockets show it well too.

 

[Onebadhawk]

Base drag is how saucers go (mostly) straight up without fins. Mini maggs and other stubbie rockets show it well too.

That makes perfect sense,,,,,,,,,,
I never thought of that.......

Teddy

 

[dh4664dh]

For what I created in RocSim, CP is 31.55 inches from nosecone tip.
- The CG for the loaded single 98mm motor was 27.49 inches, compared to 24.89 inches unloaded.
- The CG for the loaded 4 motor version was 30.59 inches compared to 24.98 inches unloaded.
I did add 4 pounds of weight to the nosecone tip to keep the CP and CG apart, if only by one inch for the loaded 4 motor version.

I know RocSim does not handle large bases very well and Apogee recommends creating a conical pyramid behind the rocket to determine stability. I did not do that.

The simulation of the 4 motor version used an air start for the three 75mm K510 motors of 10 seconds after takeoff, which is about 3 seconds after burnout of the central 98mm M 1450. In real life, I would set the altimeter to 2 seconds after burnout because it takes about a second for the Ks to come up to pressure.

And if I were to actually build it, the fins would have a smaller span to prevent flutter. Rear ejection means the pointy end hits the ground first, so the fins should be somewhat protected. I would add another tube from the back to act as the avbay and use a TenderDescender to enable dual deploy, especially needed from 14000 feet.

So if the nosecone is still for sale... it would be cool to have a central 98 (or 150mm) surrounded by three 75mm tubes.

 

[kpotter]

really its 15" by about 3 and a half feet long made of fiberglass its heavy its big any good for a big rocket or no! the guy wants 45 dollars for it!

Now wait just one minute here. You live in DE, are a member of MDRA and you have to ask whether or not to buy this thing ? There is no debate here, go get it, bring it to Red Glare, name your price and make a profit !