The XPRS launch allowed for three days (Fri-Sat-Sun) of commercial motor launches and one day (Monday) for experimental motors.  Unfortunately, the weather on Friday washed out most of the day.  The morning started out just fine, but it rapidly deteriorated into high winds, rain and cold temperatures.  In fact, all of the nights were very cold this year, getting down into the low 30's.   The weather on Saturday was much better and then on Sunday it was nearly perfect. 

The launch pads were very busy during Saturday and Sunday.   There were lots and lots of exciting flights.   One in particular was Adrian Carbine's successful N-to-N two-stage that went over 40,000 feet, reached about Mach 2, and was safely recovered.   It was an awesome flight!  Well done Adrian!   A photo of his launch and some more details about it are presented at the bottom of this page.

The experimental launch on Monday was not nearly as busy.  This was undoubtedly due to the fact that the largest experimental launch of the whole year (Balls 14) was held just one week prior.  At any rate, the highlight of the XPRS EX day had to be Tom Rouse's two-stage with three M-motors in the booster and an N-motor in the sustainer.  Unfortunately, it took off at a very severe angle and was traveling horizontally to the west when it staged.  The sustainer lit and headed toward the edge of the playa and probably well beyond.  They were still out recovering it when the launch closed.

As far as my own flights go, I (Vern) successfully launched Angelfire on an M1939 to over 15,000 feet. Angelfire was carrying my new GPS radio downlink electronics on this flight and it seemed to work very well. I also successfully flew Starfire on an M2200 Skidmark motor to just under 5000 feet. My only other flight was with my Nike Dart on a K185 to just over 10,000 feet.  It too was successful without any damage being incurred.   I'm already looking forward to next year!

This view is looking towards the flight line from the 500 foot pads at XPRS.  It was taken on Sunday morning, Sept. 25, 2005.  

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Two views of the XPRS flight line from a digital camera on-board Starfire.  Starfire was about 0.5 miles away and 2000 feet high at the point these photos were taken.  The camera is a Canon S40 4Mpix digital camera.  It snaps about 100 photos while Starfire descends on parachute.

I'm standing next to Angelfire just prior to launch on a 98mm AeroTech M1939 full M motor.  Angelfire is 11 feet tall and 5.15 inches in diameter.  It weighed 52 lbs with the motor installed.   Angelfire reached 15,329 feet in a picture perfect flight.  The dual deployment system deployed the main parachute at about 1000 feet and Angelfire touched down less than half a mile away.

The playa pretty much destroyed the paint job on the body tube and nosecone.   Both  were  severely scratched up after being dragged around by the parachute. 

Ever wonder what it would be like to be "danger close" to the launch of an Aerotech M1939 full M-motor?  Here is your chance to experience it.  Shon Heiner placed his camcorder up close to the launch pad to capture this short liftoff video.

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Six pages of analysis of the data from the ARTS recording altimeter is presented below.  You can click on each page individually to see an image of it, or you can get all six pages at once in a higher resolution PDF document.

Some interesting things can be seen in this flight data.  The two MissileWorks altimeters reported the peak altitude to be 15,198 and 15,461 feet.  The ARTS altimeter reported the peak altitude as 15,351 feet based on the accelerometer and 14,830 feet based on the pressure sensor.  These readings are all very close.  The largest difference is only 4.3%.   The MissileWorks altimeters were responsible for firing the ejection charges.  It appears that the apogee charge was possibly fired a little early.  A glitch in the ARTS acceleration data indicates the apogee change was fired at about 14,589 feet.  Slightly before the ARTS detected apogee on either the barometric or inertial data. However, it is not possible to know for sure if the MissileWorks fired early or if the ARTS detected apogee late. 

The acceleration data shows a small event at about 5.7 seconds into the motor burn.  Interestingly enough, the published thrust curve for the M1939 also shows a hint of this same event.  Apparently something happens as the motor nears burnout.  This can be seen in page 5 of the flight data.  Motor burnout occurred at 3,400 feet.

Maximum acceleration was 6.9 G's.  Peak velocity was 985 ft/sec (672 mph).  Angelfire reached apogee in 32 seconds.  After that, it descended on the drogue chute for 2.1 minutes and then deployed the main at about 1000 feet.  It descended on the main chute for 40 seconds.  Total flight time was 3.3 minutes.

The drogue chute descent rate was 114 ft/sec.  The main chute ejection charge fired at 1000 feet so Angelfire was within 8.8 seconds of hitting the ground if the main had not been deployed.  The main was not fully inflated until Angelfire reached about 840 feet.  The main chute descent rate was 21.5 ft/sec and Angelfire only spent 40 seconds on the main until it touched down. 

Vern standing next to Starfire just prior to launch on an AMW M2200 Skidmark motor.  Once you see one of these motors it will become an instant favorite!  They generate a very loud "crackling" sound with lots of black smoke and tons of titanium sparks flying everywhere.  This was the tenth flight of Starfire.  It reached 4,755 feet and was safely recovered.

Ground video of the Starfire flight.  Greg Fannin shot this video from the XPRS flight line using a handheld camcorder. Turn up the sound and enjoy!

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"Pad Cam" video of the Starfire liftoff.  Shon Heiner placed his camcorder up close to the launch pad to capture this liftoff video.  In this video you can begin to appreciate how much of the hot metal sparks from this motor reach the ground.  They rain down all around the launch pad!

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Unfortunately, there is no on-board video from this flight.  The on-board camcorder stopped tracking at the instant the motor ignited.  Apparently the acceleration was more than the mini-DV camcorder could tolerate. This has never happened before. The camcorder did not resume recording until well after apogee when Starfire was on parachute.

Greg Fannin launched his "Orange Crush" at XPRS 2005 on a long burning Cesaroni N1100 in an attempt to break the N-motor altitude record.  The rocket is a 4" diameter carbon fiber airframe with a conical fiberglass nosecone and aluminum fins.  This flight should have exceeded 40,000 feet. However, a very strange thing happened shortly after leaving the launch pad. The rocket did almost a full 360 degree rotation in the pitch plane and then continued on up in the same direction that it was originally going! A short video of the loop as well as some analysis and discussion of it can be found on the page at the link below. 

Adrian Carbine launched his 17 foot, 96-lb, N-to-N two-stage project on Sunday afternoon at XPRS 2005.  The booster motor was a CTI N2500 and the sustainer motor was an AT N2000.  The flight was flawless except for the fact the main parachute was deployed at apogee.  It reached 40,098 feet.

Click here to read all about it

Adrian said "I'm really happy about the CO₂ based staging.  It was right on for timing with a sudden separation after coasting down from the Mach 1 boost, and the sustainer motor lit up right on schedule.  The altitude was less than simulated, due to arcing over and maybe a little coning at Mach 2, but the flight overall went better than I could have hoped for."

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Photos from XPRS 2004 can be found here.