by Dan Kirk

Parts List
1 NAR standard egg
1 scrap of BT-20 about 2-3" long
1 Body Tube BT-20 8.5" long
3 Fins 3/32" Balsa
1 Crepe paper streamer about 1.75 x 18"
1 Kevlar shock cord about 36"
1 Estes engine block to fit BT-20
1 Launch lug, 1/8 x 2"

After seeing a few Egglofters DQ at NAR meets, I thought it might be fun to build a rocket that purposely ejects the egg -- preferably right over the spectators' heads.  That's it!  For those weenies who always complain when I try something new, a Weenie-Seeking Missile!

I toyed with various ideas for opening the capsule at apogee. I realized that the egg only had to survive the boost phase of the flight, and since this flight would DQ anyway, there was no need to keep the egg enclosed.

So I settled on making the egg itself serve as the nose cone.  How to make a shoulder?  Borrowing a page from Model Rocket Design and Construction, I cut a scrap of BT-20 sliced it open lengthwise, overlapped the ends, and rolled it just tight enough to fit inside another BT-20.  A few drops of CA kept it from unrolling, and I CA'd it to the egg.  Some excess CA ran down the egg and glued it to the table.  I carefully removed it, but a chip of shell was missing.  The membrane inside was still intact, so I patched it with The Handyman's Secret Weapon: Duct Tape.  Once the CA was dry and the patch was in place, the egg could sit neatly on top of the booster.

The booster was an old Streamer Duration model based loosely on the Wizard.  It already had a Kevlar shock cord mounted externally, but any type of shock cord and mount would do.  Since I wasn't concerned with duration, I used a small, cheap crepe paper streamer.  The shock cord is not attached to the nose.

I put the nose in place, and then glued the launch lug to a fin, making sure the rod would clear the egg.  Since I wanted the egg to eject nose-down, hopefully pointed at anyone who had laughed at my numerous DQ's, I selected a long delay.

I tested my design at KCAR's first launch at our new HPR field.  No weenies showed up.  I aimed the rod carefully, hoping for a direct hit with maximum collateral damage.  The rocket performed flawlessly, boosting to a good altitude and arcing over before ejecting the egg.  Someone observed, "Hey, your rocket ejected something!" My aim was not as good.  The egg sploitched about 50 yards to the right of the group.  I'll have to work on that.

Duct Tape

Gluing the shoulder on the egg

Needs a lug

On the pad

Click Here For Fin Pattern