Millennium II

(photo by Steve Rogers)

(Additional photos and video will be posted as they come in.)

Flight Summary

A successful Level 3 Certification flight occurred on June 16, 2001 in McGregor, TX.

There was low wind during the launch and a healthy opening in the clouds permitted good visibility.  The rocket weighed 54 lbs. loaded.  It was made from non-brittle phenolic reinforced with two layers of kevlar/carbon fiber cloth.  The fins were a laminate of 1/8" G10 covered with tapered plywood covered with kevlar/carbon fiber cloth and finished with a thin fiberglass sanding veil.   Rocket height was 7 1/2" dia by 10 1/2 ft tall . 

The M1315 produced a graceful lift-off.   The launch was picture perfect with a peak altitude of about 5,000 ft.   The 2 ft RocketMan 24D drogue was deployed on schedule by the AltAcc backed up with the Missile Works  RRC˛X 40k altimeter.  This stabilized the descent rate at 80 fps.  The 12 ft Sky Angle Cert3 XX-L main was deployed at roughly 1000 ft by the Missile Works.  This slowed the descent rate to 13 fps.  A subsequent backup charge was fired by the AltAcc at 546 ft AGL.   The rocket was in visual range except for the last meter or so during touchdown which occurred at 2 minutes 7 seconds.   The rocket was recovered without damage and carried back by Marlin Philyaw and Matthew Barnett.

AltAcc Data
           Drogue Fired at:    19.4375 sec   (5138 ft AGL) barometric
               Main Fired at:   90.7500 sec  (546 ft AGL)   barometric
  Max Pressure Altitude:   5138 ft AGL @ 19.4375 sec
    Max Inertial Altitude:    5366 ft AGL @ 19.3750 sec
Maximum Acceleration:    185.61 ft/sec*sec (5.8G) @ 06250 sec
Minimum Acceleration:    -56.49 ft/sec*sec (-1.8G) @ 5.8750 sec

(The drogue deployment produced roughly 4.8 G spike.  The main deployment charge produced roughly -7.8 G followed by  4.6 G when the main deployed.)

Graph of flight from AltAcc

Missile Works Data
        Maximum Altitude:   4966 ft AGL barometric

Here is one wilted, tracking powder covered builder and rocket shortly before launch. The booster was left unpainted this time so that construction using carbon fiber/kevlar would be visible.

Previous flights on M motors

Feb 13, 2000 in Windom, TX
(design info for that rocket)

Deployment Scenario
Detailed Plans: bottom section (435k), electronics section (410k)
The layout for the altimeter interface board has been improved since the launch.
RockSim: simulation results (pre-flight and post-flight), rocksim file

The rocket utilized a non-brittle phenolic airframe lined with couplers and covered with kevlar and fiberglass.  Four 1/2" 7-ply aircraft grade centering rings were used in the bottom half of the rocket.  Aluminum rail buttons were screwed into the centering rings with lengthened screws and epoxied in place.   Slow-setting West Systems epoxy was used thruout and was heated to allow it to flow into roughened surfaces.  An aluminum thrust/retainer ring was used to effectively transfer thrust to the motor mount tube, fins, and airframe.  One-eighth inch G-10 fiberglass was said to be sufficient for the fins.  However, to further stiffen the fins, kevlar/carbon fiber cloth was epoxied on each fin face.  The fins were then inserted into notched and grooved centering rings and reinforced at the motor mount and the airframe with fiberglass tape.  Externally, epoxy/phenolic filets were used.
A SkyAngle level III cert chute was chosen for the main and a high deployment speed 6 ft cargo chute was chosen for the drogue.  Tubular nylon with a 4,000 lb rating was used for the webbing and shackes rated at 1500 lb working load were used for attachments.  Each end of the webbing had two x filled box stitches securing a loop.  The ends were covered with nomex sleeves and tape was used to cover the exposed the webbing where it attached to the shackles thus insulating them from the deployment charges.  1/2 inch stainless steel U-bolts with a 5 inch diameter were used on both ends of the payload compartment and the bottom section of the rocket.   An improved metal nose cone attachment was added.  Redundancy consisted of 2 altimeters utilizing 4 separate LES units.  Each altimeter was mounted in a separate small altimeter compartment to minimize air volume.  These were mounted inside another payload compartment (open,  cover with LES) to further seal them from the deployment gasses.  Gaskets were used.  Shear pins were used and tested for both the main and drogue parachute compartments.  The amount of charge used in the LES was based on ground testing of deployment and no interaction occurred between the charges.  Both altimeters were tested for barometric deployment.   The AltAcc was also G-force tested as per the instructions.  An arming/safe interface board was connected to the altimeters in advance to minimize the probability of prep wiring errors.  To arm/disarm altimeters, short/unshort matches, and connect/disconnect the 4 electric matches, one had only to plug in the connectors (access hatch/connectors).    Molex connectors and screw terminal connections were chosen to survive extreme vibration during flight.  New tested batteries were installed.

A detailed checklist used during preparation and launch.  To insure proper ignition, a Magnalite igniter was enhanced with 4 slivers of Blue Thunder and mounted on a wooden dowel.  Electric matches were utilized inside tightly wrapped Saran-wrapped charges to prevent separation of the powder from the matches. These were placed in 1 1/2" pvc pipe caps, covered with flame-resistant insulation and the top was sealed with masking tape.  The altimeters were armed and tested during final assembly and functioned correctly.  The system was disarmed, safed and taken to the pad.  On the pad, it was impossible to see the AltAcc LED, so the rocket was safed, disassembled, unsafed, re-armed and checked for the proper blink sequence.  It showed all was ok, so the rocket was again safed, re-assembled, etc.

Rocket Description:

	Alex was very patient and helpful. He is shown here holding the paperwork in preparation for the launch. Wilson.... oops. I meant to say Buzz is hiding behind the fin section.
	Matthew did an excellent job of photographing the events leading up to the launch.  He is shown here shortly before countdown.

Video of  Flight (1.75MB)

July 8, 2000 in McGregor, Tx

(photo by Brian Wheeler)

The Aerotech M1315W is a very enjoyable motor to watch in action. The flight was beautiful and the redundant electronics, 4 charges, and shear pins all worked perfectly.  The drogue deployed on schedule followed soon by the wisp of the redundant charge.  The attitude of the parts was reasonable when the main charge blew out the main on schedule.  The backup charge for the main operated correctly after after the primary blew.  The main could be seen floating freely beside the rocket but did not open while the rocket was in view above the horizon.  The 6 ft chute was insufficient to prevent damage to the airframe, so no real advantage existed using such an oversized drogue.  I believe that a smaller drogue would have allowed sufficient airspeed for the drogue to open.

(on the way to the launch pad)