2013 Launch Reports

SLRA Spring High-Power Launch, April 6 2013, Elsberry MO

First launch with St. Louis Rocketry Association. Bad weather had caused the cancellation of the first several attempts to have a launch at the high-power site in Elsberry. April 6 was quite windy, but otherwise good flying weather.

I had built my first mid-power rocket, an Aerotech Arreaux, in January and flew it for the first time here. I carried a BoosterVision GearCam and a JollyLogic AltimeterTwo. However, I zeroed the altimeter at home the night before the launch, rather than immediately before the flight, so I did not get good data.

The flight looked good and the strong wind carried the rocket far into the cornfield under parachute. It took me some time to locate it; it had narrowly missed landing in a drainage ditch (containing water) but had drifted just beyond it. It was somewhat beat up, especially the forward end of the booster section's body tube. After looking at my video, I saw that after the rocket landed, the wind caught the parachute and picked it up, throwing it some distance through the stump cornstalks. I was able to repair the dinged body tube edges by dremeling away the ragged parts, but the decal around the forward end of the booster section had to be removed.

Arreaux, Flight #1:

Motor: AeroTech EconoJet F20W-7

Altitude: Unknown

Max Velocity: Unknown

Result: Landed in field, then dragged by wind; successful recovery, minor damage (repaired)

(TODO: images & videos)

GARLO 2013, July 6 2013, Champaign IL

Having had no luck making it to another SLRA launch since April (May launch rained/flooded out, June launch occurred while I was out of town), I made the trip up to Champaign Illinois to check out Central Illinois Aerospace's big annual event, GARLO 2013 (Great Annual Rocket Launch of 2013).

The original date was June 29, but the event was – surprise – rained out. I arrived at the park about 12:30 pm, about ten minutes ahead of the rainstorm that would send GARLO 2013 Part I packing. Fortunately, the CIA returned the next Saturday, July 6, to launch again. During the three hours I was there, more than fifty rockets launched, including two flights of my Arreaux. I wanted to see how it would perform on the smaller E20-4 motor, since I might have an opportunity to fly it at the July 20 Science Center event but need a low-altitude flight due to the size of the field.

The weather was muggy and there was virtually no wind at 1:00 pm when I launched my E flight. Although a breeze would have made us all more comfortable, the calm conditions made for beautiful, straight flights and short walks to recover rockets. The Arreaux reached 401 feet in altitude on the E20-4 with a perfect deployment and a soft touchdown in the grass only about a hundred feet from the launch pad. (The first launch attempt was a misfire, but it fired on the second attempt with a new igniter.)

About an hour later I had the Arreaux prepped for the F flight and was on the pad at 2:15. The wind was beginning to pick up and the rocket weathercocked quite a bit as it climbed. Judging by the video, it did go just beyond the edge of the park (it looked much further away) but the under parachute it drifted back toward the launch pad. It ended up about a hundred yards from the pad, having touched down on a narrow sidewalk between two soft green soccer fields. However, apart from a little scraping on one of the fins, there doesn't appear to be any damage.

Upon recovery, though, I found that the motor had been ejected. Fortunately, the parachute deployed despite this, or the Arreaux would have sailed out of the park and demolished itself on the roof of the adjoining apartment building or the parking lot surrounding it. The motor ejection was visible on the on-board video. I believe this to be because the instructions for the EconoJet motor state that a cardboard spacer ring needs to be installed in front of the motor to make the forward end of the motor meet the forward end of the motor mount (the EconoJet motors are shorter than a standard F motor). However, the spacer rings were not included with the motors as the instructions indicated, so I disregarded this instruction. I just pushed the motor in until it reached the end of the motor mount, which left a gap between the end of the motor and the retaining hook. I reasoned that the hook would still keep the motor from ejecting…I was wrong. I need to figure out how to deal with this before I fly my other two Fs (unless I just save them for the next rocket). The E motor doesn't have this problem because the 24-to-29mm adapter makes everything match up properly.

However, all's well that ends well. The Arreaux reached 712 feet altitude on the F20 motor (climbing at much more of an angle than on the E flight) and a maximum velocity of 133 miles per hour. Before I fly this rocket again I want to check its mass and CG and possibly move the camera further back so improve wind stability.

On both flights I flew the Adept Rocketry SB20 Beeper with two nuts tied to the activation jumper. On both flights the ejection charge properly started the beeper, although with it inside the payload compartment it was not really loud enough to be much use in finding the rocket if it were lost.

Weather conditions: overcast, calm, 77 F, 71% RH

Arreaux, Flight #2: Motor: AeroTech E20W-4

Altitude: 401 feet

Max velocity: 88 mph

Motor burn time: 1.4 sec

Peak acceleration: 5.8 G

Average Acceleration: 2.8 G

Coast time to apogee: 4.4 sec

Apogee-to-ejection time: 1.9 sec

Ejection altitude: 359 feet

Average descent velocity: 12 mph

Total flight duration: 26.3 sec

Result: Landed on grass; successful recovery, no damage

(TODO: images & videos)

Arreaux, Flight #3:

Motor: AeroTech EconoJet F20W-7

Altitude: 712 feet

Max velocity: 133 mph

Motor burn time: 1.9 sec

Peak acceleration: 11.1 G

Average acceleration: 3.2 G

Coast time to apogee: 7.0 sec

Apogee-to-ejection time: -0.3 sec

Ejection altitude: 682 feet

Average descent velocity: 12 mph

Total flight duration: 45.9 sec

Result: Ejected motor but parachute still deployed; landed on paved sidewalk; successful recovery, inconsequential damage

(TODO: images & videos)

St. Louis Science Center event, July 20 2013, St. Louis MO

St. Louis Rocketry Association was invited to do a public outreach program by the St. Louis Science Center as part of their commemoration of the anniversary of the Apollo 11 moon landing. We had several tables where SLRA members showed off their projects, and raffled Quest StarHawk kits for kids to build and fly on-the-spot. A photographer from the St. Louis Post-Dispatch covered the event.

(TODO: images)

SLRA August Park Launch, August 17 2013, Valley Park MO

This was the first launch I'd attended at Buder Park, which SLRA shares with the Greater St. Louis Model Association. We launch in the northern part of the park while GSLMA flies radio-control aircraft on the south side.

Since space is limited, this is mainly a low-power launch, although I had planned to try my Blue Phenix Jr. on F20 and F42 motors. However, before I did this, I launched my Arreaux on an E20, and it drifted into the trees on the north side of the park. Efforts to retrieve it the next day were unsuccessful. So I decided not to risk launching my other rocket (besides which, we did not have a blast deflector for the rail launcher).

The weather was perfect, and lots of current and former members and nonmembers and kids launched model rockets. I used my new Casio camera to capture some high-speed (240 fps) video of a few launches.

Arreaux, Flight #4:

Motor: AeroTech E20W-4

Altitude: Unknown

Max velocity: Unknown

Result: Rocket caught in treetop approx. 60 above ground; unrecoverable

(TODO: images & videos)

SLRA Fall High-power Launch, October 26 2013, Elsberry MO

My Level 1 certification attempt was successful! We had perfect weather with clear skies, temperatures in the low 60s and 10-15 mph winds. Several other fliers had high-power launches, including another H, a J, and an M (which broke its nozzle upon ignition and snuffed before it got off the pad).

My rocket wobbled a bit off the pad and weathercocked a couple of hundred feet to the northwest as it coasted. The ejection was about a second late, but got the chute out and drifted back to the east, landing about 500 feet east of the launch pad. The only thing wrong with the flight itself was that the nose cone separated from the payload section, which was not intended. When assembling the rocket before flight I found that the holes I drilled for the shear pins were not big enough and I couldn't get the pins in, so I just used painter's tape to make a tight fit between the nose cone and the forward tube. I think the excessive force of the chute opening, due to the late ejection charge, yanked it out anyway. I had the forward shock cord in place as a precaution, so no harm was done.

For this flight I flew both the Jolly Logic AltimeterTwo and the Featherweight Raven, intending to test the Raven and compare its data against the AltimeterTwo. However, upon recovery, I found that the Raven had acquired good data but the AltimeterTwo failed to detect the launch (it was still blinking in the “ready to launch” state). So the numbers below are derived from the Raven data.

I had my camera set up, but at launch time I mistakenly hit the shutter button instead of the video record button - so, no video. I should get some good launch videos next weekend at Midwest Power, though.

Weather conditions: clear, windy (from W 10-15 mph), 64 F, 45% RH

Wildman Shapeshifter Jr., Flight #1:

Motor: Cesaroni Pro38 261H120-14A (9 second delay)

Altitude: 1428 feet

Max velocity: 204 mph

Motor burn time: 2.0 sec

Peak acceleration: 7.0 G

Coast time to apogee: 8.2 sec

Apogee-to-ejection time: 1.9 sec

Ejection altitude: 1371 feet

Average descent velocity: 22.4 ft/sec (15.3 mph)

Total flight duration: 71.4 sec

Result: Landed in field; successful recovery, no damage

Flight data file (viewable with the Featherweight Interface Program)

I had intended to try the Blue Phenix Jr. on a G79, but due to the high wind I decided against it. It can wait for a calmer day.

(TODO: images & videos)

Midwest Power 11, November 1-3 2013, Princeton IL

Day 1

I arrived at the launch site about 1:00 pm after a four hour drive from St. Louis. It was quite cold, windy, and overcast, with rain showers moving in later in the afternoon, but there were still many people already flying rockets. I had no plans to fly anything Friday - I just wanted to get my bearings and ask about taking the written test for my Tripoli Level 2 certification. I watched some launches, and was put in contact with a Tripoli Prefect who proctored the test for me. I passed with a perfect score and got my certification form signed off, still thinking at this point that I might attempt my J flight on Sunday. I stopped by the Wildman Rocketry trailer to purchase an I175 motor to fly on day 2.

Day 2

Conditions were a little better than the day before. It was still cold and windy, but the threat of rain had passed, and there wasn't much blue sky to be seen. I prepped my rocket with the I175 motor, and was still unable to get shear pins to thread into the pinholes in the nose cone - that will still require some more work. I loaded the AltimeterTwo and the Pratt beeper into the forward section and took the rocket out to the pad.

Everything with the launch appeared to work just fine, except that the beeper battery apparently died shortly after I got the rocket sealed up. Apparently that was not a fresh battery. The trajectory was very stable, there was a good ejection, and the rocket drifted off to the south-southeast under parachute. I found a landmark on the horizon and headed off into the field after it. Before I found it, however, my cell phone rang - another rocketeer had run across my rocket while retrieving his own, and called my number, which was labeled on the payload compartment. Based on Google Tracks (screenshot below) I estimate that it landed about 2500 feet from the launch site (the track turns around where I met the gentleman who found my rocket).

Weather conditions: Overcast, windy (from N 12-19 mph), 47 F, 58% RH, Baro 30.00“ rising

Wildman Shape Shifter, Flight #2:

Motor: Cesaroni Pro38 411I175-14A (11 second delay)

Parameter Raven reading AltimeterTwo reading

Altitude 3171 feet 3278 feet

Max velocity 326 mph (Mach 0.43) 298 mph (Mach 0.39)

Motor burn time 2.0 sec 2.2 sec

Peak acceleration 8.4 G 9.1 G

Average acceleration 6.3 G

Coast time to apogee 14.4 sec 13.0 sec

Apogee-to-ejection time 0.2 sec -0.6 sec

Ejection altitude 3169 feet 3170 feet

Descent rate 18 mph 18 mph

Flight duration 135 sec 135 sec

Result: Landed in field; successful recovery, no damage

Flight data file (viewable with the Featherweight Interface Program)

Retrieval track (.kml file viewable with Google Earth)

Day 3

I had been considering trying a single-deploy flight on a J290 to get my Level 2 certification this weekend, and kept going back and forth on it. I eventually decided to wait, and go back to my original plan of getting a dual-deploy system, and possibly a radio tracker, working for that flight. Instead, I decided to fly my Blue Phenix Jr. on Sunday, which hadn't had a single flight yet.

Weather conditions were much better on Sunday. It was still chilly, but the sky was almost cloudless and there was much less wind. I prepped the Blue Phenix Jr. for its first flight with a single-use F26-6 “Black Max” (smoky) motor. The flight was very stable and straight, and everything looked good until ejection when the nose cone popped out of the forward section. I had been concerned about that happening and had taped it for as tight a friction fit as I could get, but with the heavy nose cone on this rocket it was still not enough - it will need pop rivets added to hold it in place before it can fly again. Fortunately the nose didn't hit anything on the ground and the AltimeterTwo was not damaged by the fall.

Upon recovery, I found that the body tube had a small (less than one inch) zipper, which will need to be cut down. The zipper also left a slight fraying on the nylon shock cord, which I hope will not be a problem in the future, since there's no way to replace it. The altimeter indicated that the “six second” ejection delay was actually 8.7 seconds.

Weather conditions: clear, breezy (from S 10-12 mph), 52 F, 52% RH, Baro 31.24” rising

Blue Phenix Jr., Flight #1:

Motor: AeroTech F26FJ-6

Altitude: 837 feet

Max velocity: 132 mph

Motor burn time: 1.6 sec

Peak acceleration: 5.1 G

Average acceleration: 3.7 G

Coast time to apogee: 6.2 sec

Apogee-to-ejection time: 2.5 sec

Ejection altitude: 733 feet

Average descent velocity: 62 mph (Altimeter was ballistic with nose cone)

Total flight duration: 18.1 sec (Altimeter was ballistic with nose cone)

Result: Landed in field; small zipper and minor fraying of shock cord due to late ejection

I bought several additional motors to last through the rest of this year and into next, including the J290 for my next certification flight, whenever that ends up being.

(TODO: images & videos)