Held on Saturday, December 16, 1995 at the University of Alabama in Huntsville
The following text was taken, with permission, from an article by Larry Scarborough, which was published in the January-February 1996 issue of the Southeastern Space Supporter, newsletter of HAL5.
On December 16, 1995 the HALO gondola design was put to its first test. After input from Al Wright, Bill Axenroth, Ron Creel and other, less official members of the design committee, I constructed a 40% scale model from wood and cardboard. This mock-up was constructed to give concrete thinkers such as myself something solid to contemplate.
The real gondola will be called upon to carry the HALO rocket via balloon to 100,000 feet. The rocket must arrive there without freezing in the near-space environment. Having risen above most of the drag of the Earth's atmosphere, the gondola must then orient the rocket nearly to vertical to insure the highest possible trajectory upon launch.
One major challenge for the gondola team is how to keep the rocket properly aimed as it leaves this carrier. The diameter of the HALO rocket is not uniform. The top part will house the oxidizer tank. The bottom part consists of the solid fuel tube. This narrow end of the rocket is trimmed with exaggerated fins. They have to be big to be functional in the rarefied air twenty miles up.
The mock-up was made to study how a system of rails running parallel to the gondola's axis might give a rocket a good start. Some of the rails contact the front (or fat) end of the rocket. Another series of rails confines the fin tips, steering the back (or skinny) end of the rocket.
To hold the gondola (and therefore the rocket's flight path) vertical, an outrigger or boom was suggested as a counter-weight. 3-point suspension was devised as a way to minimize swaying.
The stand-in for the rocket in the 40% gondola mock-up was a paper towel roll with a plastic 7-up bottle glued to one end. Masonite fins were attached to the other end. This crude model slid smoothly along the rails of the gondola when pushed by hand.
When this demonstration of the rail system was brought before the assembled multitude of rocket scientists and engineers who are building the actual HALO rocket, I saw Tim Pickens' eyes light up. In the techno-babbel that laymen such as myself find so confusing and at the same time awe-inspiring (like fat end and skinny end), Tim made a suggestion: Slap a D-motor on that sucker's tail and we'll see how that gondola-thang is really gonna work.
Knowing the frailty and imprecision of my cardboard mock-up, I must confess to a moment of doubt. Could Tim be pulling my naive, non-rocket scientist leg? But then I remembered the legend of Tim Pickens and his flying steam iron. So per his instructions, I slapped a D-motor on the tail end of the cardboard tube.
The morning of December 16 dawned crisp and clear. Tim and Gene Hornbuckle were already at the UAH ballfield when I got there. Tim devised an aluminum spar from which the gondola was suspended. It bobbed and swung and then twisted slowly in the wind.
We observed the gondola for stability. The three-point suspension limited the swaying. We attached various tails to the boom to see whether maintaining a constant orientation to the wind (a la a weather vane) would increase stability (it did not).
So the thing could hang straight. But could it stay vertical as the rocket exited? Could the rocket even get out without its fins getting tangled in the rails? The real test was yet to come. Greg Allison showed up in time to preside over a brief countdown.
Up to this point in my life, my engineering feats have been, for the most part, earthbound. Things like screening in the porch or paving the sidewalk. And they have not come under the scrutiny of real rocket scientists. Rather than aeronautical and astronautical (up in the sky for all to see, successful or not), my experiments have tended toward the biological, basement projects in which failure could be easily and privately dealt with on a dark night with a shovel in the back yard.
In the brief seconds of that countdown, I played the whole scenario over in my mind. The rocket would disintegrate on launch; the D-motor would spew sparks onto the gondola and my contribution to the conquest of space would go up in smoke; Greg's hair would redden in anger; Tim would roll his eyes; Gene would utter a thoughtful, Hmm.
I would retort defensively, Dadburn it, I'm a doctor, not an engineer.
The strangely dilated time of that countdown finally ran out. Greg closed the circuit. The rocket rose cleanly from the gondola. And quickly. Before the gondola had time to spin or tumble out of control from the recoil of that mighty D-motor, that sucker was out of there (see how well I have mastered the technical jargon?).
We lost sight of the projectile as it arched like a suicidal Scud back to the ground behind some local dormitories. The sleeping Steve Mustaikis was roused by what must have sounded to him like a sonic boom (even rocket scientists sleep in on Saturday when they are students). But I knew that the loud crack that announced the rocket's re-entry could only be the impact of a plastic 7-up bottle on the unforgiving December earth.
The post-mortum was brief. Shoulda had a parachute was the harshest criticism I heard. Neither the bottle nor the cardboard tube would ever fly again. But while the rocket bit the dust (quite literally), the gondola survived entirely intact and proved the basic soundness of its design and construction.
I learned that day that you don't have to be a rocket scientist to make even technical contributions to Project HALO. Ad Astra per ammo-tourism.
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