Updated May 15 2:00 pm:
The HALO team met at the launch site in Hampstead, NC in the wee hours of Sunday morning, May 11th. It was very cold (frost collected on the equipment) with absolutely no wind. Perfect conditions for a balloon flight! As the rocket crew tested out the payload and command electronics and fueled the rocket with nitrous oxide, the balloon crew unfurled the delicate plastic envelope on the protective ground tarp, attached the Kjome launcher and started the inflation process.
As the sun poked up above the horizon, and with just 30 minutes to go before our FAA launch window closed, we ran across 2 nearly empty tanks of helium. Concerned that we would not have enough helium in the balloon to lift the rocket payload, we searched Hampstead and nearby Topsail Beach for helium (not an easy task early on Saturday morning). It turned out the local Food Lion store had two tanks they used for party balloons and sold them to us. This saved the day and allowed us to achieve final flight lift. The rocket crew lifted the payload and stretched the lines tight, the fill tube on the balloon was tied off and the call to the FAA went out for imminent lift off. With just 5 minutes to go before the deadline, we released the balloon at 6:59 am EDT and the rockoon headed up smoothly into the still morning sky on its way to the stratosphere.
Spectacular color video of the balloon and the side of the rocket launch tube could be seen in the command tent. The rocket video was viewable on another monitor, but little could be seen due to the protective plastic wrap around the gondola.
The GPS telemetry downlinked via packet radio in APRS format started to get weak after the rockoon exceeded 23,000 feet. The signal faded completely into the noise and we unable to record any more usable position and altitude reports from that point onward. We think that the internal antenna for the packet transmitter put most of the radio signal up and down, but very little signal made it towards the horizon as the payload headed out nearly 120 miles out over the Atlantic.
At 8:21 am, we were calculated the estimated altitude of the rockoon based on the ascent rate to be around 60,000 feet. I said, "Since we are now above 49,000 feet, the barometric rocket safety switches are now armed and the rocket can be fired at anytime." Of couse, we were hoping to reach at least 100,000 feet before firing off the rocket. Just 30 seconds later, I happened to be looking at the video of the balloon envelope and thought that the balloon looked pretty full. Just then, one of the seams tore wide open, dumped out all of it's helium and the balloon just folded up into a long streamer of plastic! As the rocket and gondola dropped rapidly, I shouted out to Ed KE4ROC, "Fire that rocket NOW!". We had just over a minute to issue the fire command before the safety switch disarmed the rocket at 49,000 feet.
Ed keyed down the 2 meter transmitter and anxiously entered the firing code via touchtones. Nothing happened...He tried another time...nothing...and then a third (we had only seconds left before the safeties cut in). All of a sudden there was a bright flash and a cloud of smoke and the rocket leaped out of the gondola and off towards space. Bits of plastic tape and the plastic covering shredded off and fluttered past the camera view as the gondola continued its rapid descent. Miracously, the camera had survived the rocket exhaust blast and continued to work flawlessly until the gondola splashed into the Atlantic Ocean.
We were treated to flashes of video from the rocket for about 30 seconds showing tantalizing views of the curve of the Earth. Since the rocket was spinning around, the ATV signal fluttered in and out and made it difficult to lock onto a good picture. After that, the video signal ceased and the rocket parachuted down into the Atlantic. We estimate our peak altitude at 38 nautical miles. Both the gondola and the rocket splashed down about 120 miles east of the launchsite and 50 miles from the nearest land. Since the GPS signals were unavailable, we were unable to direct the chase boat to an accurate splashdown location. The rocket and gondola were very small straws in an extremely large haystack and as a result, the chase boat did not recover the payloads.
Although we did not achieve space (defined as 51 nautical miles in altitude), we did set several records: The first amateur launch of a rockoon (rocket launched from a balloon), the highest launch of a hybrid rocket (hybrid referring to the nitrous oxide/asphalt fuel combination), and the highest flying hybrid rocket to date. (de Bill Brown WB8ELK)