You'll notice that initial tilt straightened right out to vertical. Now let's back up before the launch...
First off I seem to have misplaced my stainless steel seal disc, required for AT Super Thunder 98mm reloads, at home. I have yet to really dig for it but emailed David Reese, fellow TAP and proprietor of Wildman West Rocketry, and he Kindly said he'd loan or sell his spare to me. I purchased his so now there are two such 98mm discs in my home; handy.
I'd performed a bit of prep the night before but, as previously noted, I'm slow. The wind was kicking up from zero to substantial as my prep wrapped up. I was committed to launching, however, so I just kept moving forward. As I neared the LCO table I encountered Kurt Gugisberg; the TAP who'd signed off on my L3. He noted that there wasn't a 1515 rail at the 500' pads but offered to grab one from the club's trailer. He then kindly walked with me out to the pad and helped me load up this 44lb beast.
Earlier this month (Feb) I learned that my GoPro Hero 5 camera shoots 240 fps in 720p at Holtville. I'd never noticed the resolution increase from 480p since I'd apparently never explored the camera's UI. Dum. In any event I was all psyched to shoot this M4500 liftoff at 240fps and was indeed running the camera in this mode while the rocket was on the pad.
Then I headed in to the LCO table, manned by David Reese, only to learn that I'd neglected to connect the installed initiator leads. Dum. I then walked out to the pad pausing the GoPro on the way. I connected the leads and headed back to the table. Note that I hadn't restarted the camera. I realized this but the wind seemed to steadily increase so I opted to skip the slow-mo vid of this launch and instead shot the above still sequence hand-held.
Liftoff was essentially instantaneous and the Mega Cowabunga quickly roared to a lofty altitude. I'd estimate that flame to be roughly 10-11 feet long. Again Epic. I saw the ejection at apogee but then lost site of the rocket under 'chute. Luckily I had a clean Comm-Spec transmitter signal and began walking downwind (East) following that signal. I ended up trekking 2 miles E-NE and found the rocket intact:
I'm estimating the endpoints of the above line drawn in Google Earth but they're pretty close. Kurt noted that the owner of that property where my rocket landed was speculated to have gathered many previous rockets and may have them in a spare room. Noted, Kurt, but mine escaped such a fate this day.
My new Raven4 altimeter seems to have worked flawlessly alongside the Raven3. The average of the two devices is:
Altitude (AGL): 9,668 ft
Speed: 811 MPH (speed of sound is 771MPH @ 73˚F so mach 1.05)
Acceleration: 37.6 gees
Here are screen grabs from the Featherweight Interface Program:
Raven4: (altitude, speed, accel)(tabular)(acceleration only, thrust curve)
Raven3: (altitude, speed, accel)(tabular)(acceleration only, thrust curve)
As I slowly walked the Meg'Cow' back toward my car I noticed that the sustained winds had shut the range down. Kurt then handed me both 1515 rail guides as they'd separated from the rocket under intense acceleration. Oops. I'm grateful the ascent ended up so vertical!
So I remain a big fan of Aerotech Super Thunder propellant. Having now flown their L2500 and M4500 I'd like to fly the M6000; as prompted by David Reese. Look for this flight in the future but I still have to fly the CTI M6400; hopefully at Holtville Havoc in March. Thanks for reading!
Addendum: I forgot to mention that I lost my CD3 (CO2) assembly. It ejected the 'chute then ejected itself from its attachment to the shock cord. If you found a CD3 assembly on Lucerne Dry Lake after the launch please consider returning it. Thank you.
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