Rocket Recovery

Bridgerland Radio Rocket Recovery
Activity Report
Guy Hatch N7WAT
June 20, 2010
This was the second BARC activity in support of the Experimental Sounding Rocket Association, headed by Dr. Paul Mueller. Last year’s experience confirmed the need for radio tracking of the rockets. BARC again this year offered to field a team of amateur radio operators, with beacon transmitters and directional antennas, to assist with this effort. This year’s radio team included Guy Hatch, N7WAT, Stan Wellard, W7SJW, Ron Felstead, KF7EQQ, and Ron’s 11 year old grandson, Jacob Hansen, KF7KPR, who had just received his Technician license on June 10. We were joined by Ron’s wife, Kathie, two more grandsons, 11 year old Bennett and 13 year old Tristan Felstead, and Guy’s son, Daniel. Kevin Kesler, KE7AAF, joined us at Green River, but was not able to stay long enough to witness a launch. However, he did assemble and test his antenna and UHF equipment and was ready to go. Six university teams had initially signed up, but two dropped out just prior to the competition. This left BYU, Embry-Riddle Aeronautical University, from Daytona Beach, Florida, UCLA, and USC-Long Beach. UCLA was preparing two hybrid-fuel rockets and was planning to do a static firing of a motor identical to the one they built for their larger rocket prior to launching their larger rocket.
 
Our radio team preparations included purchase of two 70 cm Yagi antennas and building of three offset attenuator kits. Guy’s VHF base station antenna mast was partially rebuilt to include a new omni-directional antenna with a weather vane flag mounted at the top. Two direction-finding practice sessions were held in the weeks prior to the activity. These were held at the Lundstrom Park in Logan, and were also attended by Tom Carlisle, KF7EBX and Rik Stallings, N7XZ, who were not able to go to Green River this year, and Kevin Kesler. We contacted John Mabey, Simplex Frequency Coordinator of the Utah VHF Society, to request frequencies for our activity. He assigned us 145.750 and 145.570 MHz simplex and 5 frequencies in the 70 cm band, separated by 50 KHz, starting at 439.000 MHz, going up, for our beacons. Rik Stallings programmed the two BARC transmitters and his two, which he graciously loaned to us.
Ron had recently purchased a mobile Yeasu HF/VHF transceiver, an LDG YT100 automatic antenna tuner, and an 80/40 meter NVIS antenna system. Guy brought his Kenwood TS-120S transceiver, an MFJ-949C antenna tuner, and a G5RV dipole, which he hoped to mount on the base station mast. We all had HT’s, including Jacob. We also used two FRS radios for communications with launch control and some of the search teams.
We started from Logan about 9 a.m. on Wednesday, June 16, stopping to pick up Jacob, Tristan, and Bennett on the way. We arrived at the John Wesley Powell museum in Green River City at about 3 p.m., but had to wait until about 6 p.m. for Paul Mueller to lead us to the launch site. Wednesday’s weather was very windy from about Price, south; constant at about 30 mph, with gusts to over 40. This wind apparently worked loose one of two folding tables strapped to Ron’s roof rack somewhere between Price and Green River, and it blew away without being noticed. He had to find room for the remaining table inside his pickup shell, or it would also have blown away. On arrival at the launch site, we selected an area for camp/observation post/radio station and made hasty preparations for the night. Gratefully, the wind died down a bit after midnight and from the next morning on, we had clear skies and only occasional breezes, warming to over 90 degrees by late afternoon. We were all very grateful for Ron’s shade tent!
 
There were four launches and no explosions this year. BYU’s rocket was ready first and launched into a slight breeze from the north-east. Unfortunately, higher elevation winds were going north. Their drogue parachute unintentionally pulled their main parachute out with it at apogee, approximately 10,000 feet up. Yes, it did drift -- over the bluff about a mile away. We had both radio and visual contact with it until it dropped behind the ridge, at a bearing of 10 degrees, so we at least knew where to start the search. Since the BYU launch was just before 3 p.m. and two other rockets were ready to go, launch control decided to have all three launches go in quick succession, with all search teams released together after the third launch. Guy accompanied the BYU team, Ron and Jacob worked with the Embry-Riddle team, whose rocket also accidentally deployed its main parachute at apogee, along with its drogue parachute, and drifted about two miles further than the BYU rocket at a bearing of about 40 degrees. Unfortunately, Long Beach decided not to use a radio beacon. Very unfortunately, their main parachute also deployed at apogee into a rather brisk high altitude wind, carrying it well beyond binocular view before dropping below the ridge at a bearing of 34 degrees at last sighting, when it was still at least 10 degrees above the visual horizon and settling very slowly. The BYU rocket was located a few hundred feet beyond the ridge, about 1 mile from launch, and was quickly recovered. Ron and Jacob found an S1-S2 signal from the Embry-Riddle rocket beacon upon reaching the first ridge, then went over a second ridge to get an S4-S5 signal in the same direction. At each point, the ERAU search team looked back for directions from Ron, helping keep them on track in a very complex pattern of hills and gullies. They eventually found their rocket, nosecone buried like a solitary fence post in the ground just beyond the third main hill and about three miles from launch. On return, they all confirmed that without Ron and Jacob’s guidance, they probably would not have found their rocket within the 2 hour limit. Unfortunately, without a radio beacon, and with a very long drift, the Long Beach rocket search was postponed until Friday morning. On departure, the search team stopped by our observation site to get a compass bearing. Due to the required distance from launch, observers were asked to stay so far away from the launch rail that they could not see the distant ridgeline to get a visual fix on the last sighting. We were considered part of the launch team and allowed to stay at our chosen site, which was about 600 feet from the launch rail and had an excellent view of the down-range. Friday morning we gave the Long Beach team our last visual bearing of 34 degrees, which lined up with the Green River City municipal airport about six miles away, and they set out at about 9 a.m. We received a radio report from launch control that LC had received a cell phone call from about 1 mile before the airport to report that the Long Beach team had found their rocket. They were fortunate to be able to carry their rocket only about a mile to a power line access road to get a ride back to the launch area, returning a little past noon and very tired and hot. They reported that they had spread out in a line of six searchers, each on a ridge-line, and keeping visual contact with the next on each side as they swept the terrain in the planned direction. They were very grateful for our direction and vowed to use a radio beacon next year. They all vowed to work on their parachute-release mechanisms, too!
We had a bit of a problem raising Guy’s antenna mast. Seems there was still just enough wind to make it rather shaky, and it did a back-flip and nosed, top end first, into the ground, snapping the PVC antenna pipe near its base and breaking the mast in three places. Fortunately a piece of broken PVC pipe and some duck tape (AKA rocket tape) enabled a much shorter, but effective, mast to be erected, placing the VHF antenna about 15 feet up. This worked very well for our local simplex communications, but wasn’t high enough to mount the G5RV. Guy hooked his HF rig to Ron’s NVIS antenna we checked into the Beehive Utah net at 12:30 p.m. on 7272 KHz on Thursday. During the day, Friday, while we waited for UCLA to prepare to launch their smaller rocket, we had a chance to try out Ron’s HF rig. He had good signal report from the Beehive Utah traffic net and was pleased to have learned some basics of running his system.
During the morning, Friday, the boys went exploring over to the Nine-Mile reservoir about a half mile East of our site. Jacob checked in regularly and reported that they found a muddy patch, with trees around it, and chased some frogs. After a prolonged period trying to fix a leak in their liquid nitrous oxide plumbing system, UCLA was ready to launch by about 3:30 p.m. Friday. About noon, Friday, we started to pack up camp, except for the shade tent and our tracking equipment, then waited, and waited. The launch was spectacular; well worth the wait. That little rocket took off straight up and disappeared from site in less than two seconds – and kept going! A few seconds later, someone called out that they saw a piece coming down to the North, without a parachute, and they followed it visually to impact. Moments later, someone else noticed the main parachute deploy at about 1500 feet, almost directly overhead. The slight breeze carried it toward Nine-Mile reservoir, where it dropped out of site, but with a clear radio signal indicating that the avionics package was intact and with the parachute-attached portion. Daniel, Jacob, and Tristan took off on a dead run, along with the UCLA recovery team. Jacob called in to report the rocket was hung up in a tree, then called in the altimeter reading when the team got it down. One would have thought he had been a ham for years; very professional and confident. The free-falling object turned out to be their motor – about 5 pounds of aluminum pipe. The tether strap to the motor was not frayed or broken, so the carabineer (not found) attaching it to the rest of the rocket probably broke, allowing the motor section to fall separately.
All in all, we did well! Three rockets with tracking beacons were found within the 2 hour window, one with definite benefit of the radio beacon and directional antenna to help find it. All of the launches exceeded 10,000 feet, with recovery of all electronics hardware and some great video taken by one of the rockets. Our visual observation of their launch helped Long Beach limit their search to the correct area and eventually find their rocket. A spare, fully charged car battery we brought for backup radio power was loaned to launch control for the UCLA launch when the launch rail battery went dead. There were no injuries. Damage was limited to two of Ron’s tables and Guy’s antenna mast. Great learning experiences were had by all. Tristan and Bennett will probably work toward getting their Technician licenses and their own HT’s by next year. Ron will be working HF on his new system. We will have to call this one a success.
73
Guy N7WAT