ASK 't Harde, 2 October, 2009 - Thursday 1 October was the usual preparation day. Three towers were build: NAVRO's 6 meter and 3 meter (HPR) launch towers and NAVRO's motor test stand. While preparation en certification of the rockets and their motors took place several motor tests were done by the NAVRO. These were motor tests CMT0901-CMT0903 (CMT0904 was done Friday). These test motors have our Kalinitrox as propellant and have just a single Bates-grain. The flight motor will have six grains. CMT0901-CMT0903 were all similar in composition, but each had a slightly smaller throat diameter. This could be seen in the results of the tests, as the motor pressure steadily rose.
The next day we woke up with very rainy weather. After preparations were done the last motor test was done. CMT0904 was a rerun of yesterdays CMT0903, thus having the same throat. After a little more than 3 seconds the safety membrane gave way. This means that the pressure in to motor had reached a value of more than 8000 kPa (80 Bar) and to safe the equipment the brass safety membrane breaks, which creates a second, much wider throat that lowers the pressure in the motor. Later is was discovered the throat was not cleaned after the last test and thus probably was clogged up with residue from the third test. More information can be found on the CMT0901-CMT0904 pages.
The first launch of the day was that of Pleun Punt's classic UFO. It's flight was successful and its onboard altimeter registered a maximum altitude of 80.5 meters (265 foot). The red flare of its Ceseroni Pro38 H120 Red Lightning could clearly be seen. Next was the flight of SRP15 "Menhir's". Although successfuly flown last May and thereby having won the 2008-2009 season of DARE's Scrambled Eggs competition, in flight it soon became unstable. It crashed after in erratic flight.
The next pair of rockets were Fred van Arkel's somewhat familiar locking rocket "Geinig Jolig Luchtvaartuig Beta" (Great Jolly Launcher Beta) and senior DARE member Hein Olthof's Aeolus. Before either was launched Aeolus fell partially out the launch tower as one rail guide broke lose. The rocket was quickly made safe, but could not be repaired to be launched this day. It was replaced by Olga Motsyk and Bryan Tong Minh's The Princess. Which was launched after the "Geinig Jolig Luchtvaartuig Beta" had a misfire. The Princess' flight was also very unstable and it too crashed. After an other attempt the AeroTech H128W of the "Geinig Jolig Luchtvaartuig Beta" misfired again and hereby it ended NAVRO and DARE's launches.
One the other side of the field one other launch took place. For a jubilee NERO had made their H12 rocket at the a last minute. The rocket had a great flight and reached some 1200 meters (4000 foot) and successfuly parachuted. Fortunately NERO finally ended their string of failed parachute deployments of recent years.
The bad weather, the day was interrupted several times because of the rain, and the failed launches made for a miserable day. The altitude record on a NLD launch for a successful flight of 80.5 meters will probably stand for some time to come. DARE's SRP-motor of 2009, which was used in all three DARE rockets, proved to be a highly unreliable motor. The problem was most likely bad alignment of the Bates grains in the motor. At the last launch many SRP rockets also were unstable too, but then the strong winds were given blame (which was not the case at this launch). Looking back, most would probably have flown better with another motor.