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Steve Baughman
Web Updated Jul 3
© 1999
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MK V UPGRADES - PARADISE 3 - HEART OF TEXAS 99 - RDS DEAL
Austin, TX - This is the third of our regular series of online updates designed to help keep viewers informed of XRV program development and spread the word about significant launch events. Since the last update, the XRV was launched seven more times, with four of these flights using the XRV Mk IV booster and three flights on the new Mk V booster. This brings the total number of flights in the XRV development program up to thirty-three, with the total burned impulse now equivalent to 40,283.3 Ns since July of 1998.
XRV RECEIVES AVIONICS UPGRADES AND NEW MK V BOOSTER
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The XRV Mk V weighs almost 20 lbs when in a full 5120 Ns configuration. Photo by Rita Baughman
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Flight simulations using wRASP indicated ascents likely to exceed 20 seconds in duration when using virtually any 75mm power configuration. Unfortunately, the Telemetry Microcontroller Unit (TMU) version 0.3 software was designed to provide only 20 seconds of hi-res (20 Hz) ascent time before switching to its low-res (2 Hz) mode. This was clearly inadequate to provide accurate integration of accelerometer readings for altitude measurement. After a short discussion with lead programmer Jim Baughman, the TMU software was modified to allow for 30 seconds of hi-res flight. This version 0.4 software upgrade also included a correction to the pressure scaling constant that was erroneously set at 111 feet per A/D unit instead of the more accurate 103 feet.
Then something weird happened that we would not be aware of until after Heart of Texas 99. Apparently, in our eagerness to demonstrate the extended Undo functions inherent in the Linux operating system, we somehow undid all the changes that we had just added to the software, and then burned the new microcontroller. The result was a microcontroller which was labeled as version 0.4, but which had none of the intended version 0.4 changes. The end result of this error would be delayed drogue deployment after apogee on ascents lasting more than 20 seconds, as well as artificially high altitude values reported by the TMU's reporting algorithm. These effects were not detected until data reduction of the HOT99 flights. Read on to learn more...
PARADISE 3 A SUCCESS DESPITE MARGINAL WEATHER
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The XRV Mk IV burns a K550W on flight 28 at Paradise 3. Photo by Brett Noake
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This author, as it turns out, was perhaps the most excited of the group for a couple of reasons. First of all, I had recently completed work on the improved XRV Mk V booster and avionics upgrades, and I was beside myself with enthusiasm and eagerness to begin my flight testing of these new capabilities. Secondly, it was I who volunteered to be the launch coordinator of Paradise 3, since Tripoli Hill Country prefect Lou Catozzi was unable to attend.
With my less than one year's experience in high powered rocketry, I was apprehensive about my ability to put all the pieces together in a timely and organized fashion to produce a successful launch. Thankfully I had a lot of help from many folks from all over Texas and the launch went very well in spite of what turned out to be marginal weather. The winds were fierce on both days, with a steady 15 mph wind gusting to 25, and a low cloud ceiling in the mornings which would slowly rise as the day progressed. This provided a challenge to flyers who either had to fly below the clouds, or shoot for a fleeting gap between them. In spite of these challenges, over 140 flights were made during the course of the weekend.
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Jim Long certified to level 3 at Paradise 3 after the cloud ceiling lifted high enough. Photo by the author |
Due to my responsibilities as launch coordinator, I did not have the time on Saturday to do any flying. Though on Sunday I was eager to debut the XRV Mk V for it's inaugural flight, in light of the high winds and cloudy conditions, better judgement prevailed and I did not fly the Mk V, instead settling for some respectable flights with the ever reliable Mk IV.
Flight 27 was made on a J415W rated motor, but due to user error during downloading (inserting serial cable while powered on), all flight data was lost. I chalked it up to mental exhaustion and continued with my flying. Flight 28 in the XRV program was made on a K550W, but again mental exhaustion due to my coordinator role caused me to lose the flight data thanks to a stupid mistake. This time, in my eagerness to demonstrate the TMU's one-touch arming feature to an inquisitive onlooker, I forgot that to do so would wipe all the previous flight data which I had not yet downloaded to my laptop. After extracting my boot from my posterior I concluded that it's really tough to run a launch and fly rockets at the same time. The worst part is, with no data to examine, I was not alerted during Paradise 3 that the TMU software was actually version 0.3 masquerading as 0.4.
XRV MK V BURNS L-RATED MOTOR AT HEART OF TEXAS 99
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Coordinator Ed Jacoby at the HOT99 range head. Photo by the author.
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Vendors in attendance included Trailing Edge Technologies and Odyssey Productions from the Dallas area, and Giant Leap Rocketry from Baton Rouge, Louisiana. Delicious BBQ brisket was catered both days by a group from the Eden Chamber of Commerce, the Eden Public Library, and a San Angelo girl's softball team. We had never eaten so well at a rocket launch before! Hill Country Tripoli will donate $250 of the launch fees from P3 and HOT99 to benefit the Eden Public Library.
Ed did a fabulous job running the launch, which I appreciated greatly since that meant I could do some serious flying! The weather was fairly windy both days (it is ever not windy in west Texas?), with early morning clouds burning off totally by mid afternoon. Over the weekend 30 flyers chalked up an impressive 99 flights, more than half of which were J impulse or greater.
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The XRV Mk V debuted at HOT99 on flight 30 using a 75mm K560W motor. Photo by the author. |
Flight 30 in the XRV program was made using a 75mm Aerotech K560W motor in the XRV Mk V. After some initial problems with a shorted pad cable, the K560W roared to life and months of waiting were brought to a close with the beautiful ascent of the Mk V. The rocket deployed the parachutes and landed within a couple hundred yards.
Unbeknownst to me at the time, the post-flight TMU download reported an erroneously high altitude, and the rocket had experienced a delayed drogue deployment, due the TMU version mix-up mentioned above. All Mk V flights experienced similar issues but deployed the recovery systems appropriately regardless. The actual performance of flight 30 was 470 mph in 4.1 seconds, 8 g's and a maximum altitude of 7087 feet.
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On flight 31 the XRV Mk V reached over 629 mph using an L850W motor. Photo by Mike Hudgeons.
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Saturday night was spent with a few other die-hard rocketeers, launching lightstick and strobe-equipped G80 powered rockets into the night sky and then walking in the dark to retrieve them. Most, but not all of the rockets were recovered successfully. At midnight I retired to the Morocco motel in Eden for a good dose of air conditioning and sleep. I arose Sunday morning to a deliciously greasy breakfast at the motel cafe, and headed back out the launch site. Speaking of the launch site, here are a couple of tips: (1) Tarantulas are not overly poisonous and can be handled. (2) Rattlesnakes are potentially deadly and cannot be handled. It's important to watch where you step in west Texas, contact your local Texan for more details.
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Rocket recovery offers the chance to see the lovely Texas countryside. Photo by Mike Hudgeons |
At this point I couldn't help myself from loading up a 75mm motor in the Mk V. I selected another K560W, and loaded and prepped the rocket for a fifth flight at this event. I had high hopes for matching my previous record of six flights in a weekend (NTHP14), however it was not to be. Though the rocket scorched off the pad in typical 75mm fashion and hit 6881 feet with a maximum velocity of 486 mph and maximum g-loading of 8.4 g's, the stiff breeze and a late drogue deployment made for a lot of downrange drift. I spent about an hour retreiving the rocket with some help from it's radio tracking transmitter, while enjoying the company of Gary Estes, who accompanied me on the recovery. To my surprise, when we returned most of the rocketeers had left and the site was being packed up, though it was only about 3:30 pm Sunday with four and a half hours remaining on the FAA waiver. I reluctantly called it a day though the weather at this time was ideal.
On examination of all flight data, it was obvious that the TMU software version 0.4 upgrades were not present. Though not visible on any of the Mk IV ascents, the longer duration of the Mk V ascents caused the TMU to switch into lo-res (2 Hz) mode before apogee, which artificially 'stacked' the readings after 20 seconds and caused a delayed drogue deployment. Though this did not interfere with pressure altitude measurements, it caused significant errors in altitude measurements derived through integration of acceleration data. It was then discovered that the A/D scaling function for pressure readings was still set to 111 instead of 103. These issues have been fully addressed in the new version 0.5 TMU software, which is now ready for testing on an L850W-equipped XRV Mk V on July 17, in Windom, Texas.
Flight data:
Flight 29
Flight 30
Flight 31
Flight 32
Flight 33
BAUGHMAN SELECTED TO BURN DEMO RDS N-MOTOR AT BLACK ROCK IN 2000
At this time we are very pleased to announce that a verbal agreement has been made between Steve Baughman, developer of the XRV Rocket Chronicles, and Mike Gillette, owner of Rocket Dyne Systems (RDS). Mr. Gillette has agreed to provide an RDS N-rated 98mm motor reload and the use of an appropriate motor case free of charge to Mr. Baughman, in exchange for Mr. Baughman providing extensive photo and video coverage, internet publicity, and launch reporting of the event for RDS. The launch is to be held in the Black Rock desert of Nevada early in the year 2000, using Mr. Baughman's XTRM rocket, a two-stage capable RDS Hercules RD-300.
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