Basic Information
Name	Z-21
Launch date:	3 October, 2015
Rocket description	- 63.5mm aluminum airframe - 4 fins, birch plywood, reduced span - birch elliptical nosecone - 3 ft. ellipsoidal parachute
Payload	- Raven altimeter - Minicamcorder (HD) - Microcamcorder - BRB900 GPS transmitter - Smoke charge (high output) - Apogee Backup Timer
Liftoff mass	2.503 kg.
Flight objectives	- Confirm operation of Backup Timer by video

Motor details
Motor name	Impulser
Propellant	KNDX
Grain mass	301 grams
Nominal impulse	354 N-sec
Class	I

Additional information

Microcamcorder mounted externally (near C.P.), forward facing, to capture smoke plume from Backup Timer pyro charge, to verify firing of pyro following expected time delay from liftoff.

Weather conditions
Temperature	14°C
Wind	S 10 km/hr with gusts to 15
Sky	Sunny; partly overcast with scattered cirrus clouds
Other	Humidity 56%
Ceiling	unlimited

Launch Event Description

Setup of the rocket once again went smoothly with no glitches. A checklist was used to facilitate setup. Raven confirmed all three pyro charges had continuity. A video camera was set up 250 feet from the pad (at the launch controller station) to capture liftoff and initial ascent. I used the hand-held camcorder (with scope tube) to attempt to film the complete flight. After verifying the sky was clear, the countdown proceeded. When ignition switch was closed, a gentle ‘pop’ sound was heard from the igniter and a second later the rocket soared off the pad, climbing very straight. The motor burned for about a second and the rocket was clearly visible much of the way to apogee. We heard a faint “pop” sound of the apogee charge. The smoke cloud from the charge was then sighted and shortly after a trail of smoke was seen, together with a second smoke cloud. The free-falling rocket was readily seen, aided by the trail of smoke and occasional “flash” as the sun glinted off its reflective tape. The breeze carried the descending rocket downwind. At about 500 ft. altitude, the chute pyro charge fired, and the chute was seen to quickly deploy and fully blossom. Rocket seemed to descend unusually slowly for the first 10 seconds or so of descent. Then it started to gyrate, as if caught by a wind gust, once it was a few hundred feet above the ground. Touchdown site was estimated at about 300 metres away. The landing locator was used to record the direction of touchdown, as a redundant measure to help ensure recovery. The GPS readings from the BRB receiver were then entered into the Garmin hand-held GPS unit. The distance was indicated at 0.21 miles 338 m.). We proceeded to follow the direction indicated by the GPS. A while later the rocket was recovered, in great shape, exactly where touchdown had been indicated. Raven beeped out a max altitude of 2621 feet.

Flight Analysis
Event:	Time (sec)	feet	metres
Apogee	13.1	2622	799
Separation	13.9	2609	795
Main deployment	42.3	531	162
Touchdown	70	-	-
Range	-	1066	325
Descent rates:	ft./sec.	m/sec.
Free-fall	77.3	23.6
Main parachute	13.9/18.8	4.2/5.7

Post-flight analysis and comments:

Post-flight examination confirmed that the rocket was in perfect shape after landing. The Apogee Backup Timer system once again worked nominally, as pyro charge had fired, and the out-board video footage confirmed a smoke plume at the 16 second mark. The on-board video footage was very good, and also captured the backup pyro smoke plume. The high output smoke charge produced a readily visible trail. The Raven data confirmed, as suspected, that the rocket descended unusually slowly when the chute first deployed. There may have been an updraft, as the descent occurred over the side of a hill. The hand-held camera footage captured nearly the entire flight. The scope tube made this possible.

Raven baro and accelerometer graph:

Barometric and axial acceleration data Z-21\Z-21_Raven.jpg

Acceleration during motor burn Z-21\Z-21_Raven_burn.jpg

Big Red Bee

BRB GPS tracking of flight Z-21\brb_mapped.jpg

Photos:

Rocket on pad, with my brother Blair looking on Z-21\DSCN0029a.JPG

Liftoff and ascent Z-21\ascent-1.jpg

Z-21\ascent-2.jpg

Liftoff, capture from on-board camera Z-21\ob_liftoff.jpg

Ascent, capture from tripod camera Z-21\ascent_tripod.jpg

Ascent, capture from on-board camera Z-21\ob_ascent.jpg