Basic Information

Name

Z-24

Launch date:

19 March, 2016

Rocket description

- 63.5mm aluminum airframe

- 4 fins, birch plywood, reduced span

- birch elliptical nosecone

- 3 ft. ellipsoidal parachute

Payload

- Raven altimeter

- BRB900 GPS transmitter

- Smoke charge (activated by Raven)

- Apogee Backup Timer

Liftoff mass

2.343 kg.

Flight objectives

- Test modified parachute deployment method

 

 

Motor details

Motor name

Impulser

Propellant

KNSB

Grain mass

303 grams

Nominal impulse

357 N-sec

Class

I

 

Additional information

To improve reliability of parachute extraction, a disc was installed on the parachute tether. The disc is intended to pull out the parachute directly, rather than extracting chute by pulling out shroud line connection. Also the amount of masking tape retaining the nosecone was increased by 14%. A ground test verified improved operation.

 

Weather conditions

Temperature

0°C

Wind

WNW 10-15 km/hr

Sky

Clear; clouds approaching from west horizon

Other

-

Ceiling

unlimited

 

Launch Event Description

When we arrived at the launch location, we noticed quite a lot of water in surrounding fields due to snow melt. Taking the wind speed and direction into account, we chose a launch site to hopefully provide for touchdown on dry (snow covered) ground. There was enough snow remaining on the ground to allow for use of the sled for hauling. Setup of the rocket once again went smoothly. A checklist was used to facilitate setup. Raven confirmed all four pyro charges had continuity. Backup timer was tested and confirmed to be operating nominally. A camcorder was set up on a tripod to capture liftoff.  I used the hand-held Sony camcorder (with scope tube) to attempt to film the complete flight. After verifying the sky was clear, the countdown proceeded. Immediately after ignition switch was closed, the rocket soared off the pad, veering slightly into the wind. The motor burned for about 2 seconds. The rocket was visible most of the way to apogee, with the bright sun illuminating the fluorescent orange paint, and reflecting in “flashes” off the chrome bands. About five seconds after disappearing from sight, a white smoke cloud appeared, signaling a successful apogee separation event. The rocket was then sighted tumbling down, visually made clear by occasional flashes of the sun glinting off the rocket. A second smoke cloud then appeared, resulting from the backup pyro charge firing. The rocket continued to tumble, with no sign of a smoke trail, for another 20 seconds or so. A smoke cloud suddenly appeared as the parachute charge fired, accompanied by a ‘pop’ sound a second later. The parachute immediately blossomed and the rocket gently drifted earthward, carried downrange by the wind. A thin wisp of smoke suddenly appeared, trailing the rocket on its final descent. Rocket touched down in a snow-covered field. We then programmed the BRB GPS coordinates into the Garmin hand-held GPS unit, which indicated the landing site was 0.15 miles away.

 

When we arrived at the touchdown site, the rocket appeared to be in perfect condition. We noticed the smoke charge had burned, as we’d expected.

 

Before packing up, we used the portable wind vane and anemometer to measure and record the wind direction and speed.

 

Flight Analysis

Event:

Time (sec)

feet

metres

Apogee

13.2

2776

846

Separation

14.3

2764

842

Main deployment

41.3

831

253

Touchdown

80.9

-

-

Range

-

484

148

Descent rates:

ft./sec.

m/sec.

 

Free-fall

78.1

23.8

 

Main parachute

18.1

5.52

 

 

Post-flight analysis and comments:

Post-flight examination confirmed that the rocket was in great. The improved chute deployment worked well. The Apogee Backup Timer system apparently worked nominally, as pyro charge had fired.

The reason for the delayed Smoke Charge firing was a result of a setting used for the Raven 4th channel. As this channel is normally intended as a backup for the main chute pyro, the default condition is “altitude less than 700 feet”. For future flights, this condition will be changed to “any altitude”.

 

Raven baro and accelerometer graph:                                                

Barometric and axial acceleration data                                                 Z-24\Z-24_Raven.jpg

 

Big Red Bee

Launch and landing locations                                                                   Z-24\Z-24_BRB.jpg

 

Photos:                                                                                                         

New launch pad                                                                                           Z-24\DSCN0288.JPG

Z-24 Rocket on pad                                                                                     Z-24\DSCN0291.JPG

Liftoff (view from tripod camera)                                                            Z-24\nikon_1.jpg

                                                                                                                        Z-24\nikon_2.jpg

Liftoff and ascent (hand-held camera)                                                   Z-24\Z-24_sonycapture1.jpg

                                                                                                                        Z-24\Z-24_sonycapture2.jpg

                                                                                                                        Z-24\Z-24_sonycapture3.jpg

                                                                                                                        Z-24\Z-24_sonycapture4.jpg

Apogee pyro smoke cloud                                                                         Z-24\Z-24_sonycapture5.jpg

Backup pyro smoke cloud                                                                          Z-24\Z-24_sonycapture6.jpg

Rocket free-falling                                                                                      Z-24\Z-24_sonycapture7.jpg

Parachute pyro fires                                                                                   Z-24\Z-24_sonycapture8.jpg

Chute deploys and opens                                                                           Z-24\Z-24_sonycapture9.jpg

                                                                                                                        Z-24\Z-24_sonycapture10.jpg

                                                                                                                        Z-24\Z-24_sonycapture11.jpg

Gentle descent                                                                                             Z-24\Z-24_sonycapture12.jpg

Smoke trail is seen                                                                                      Z-24\Z-24_sonycapture13.jpg                                                                                                                       

Rocket at touchdown site                                                                         Z-24\DSCN0294.JPG

                                                                                                                        Z-24\DSCN0295.JPG

                                                                                                                        Z-24\DSCN0296.JPG

Author with Z-24 at landing site                                                               Z-24\DSCN0298.JPG

My brother using power screwdriver to reel-up ignition wires          Z-24\DSCN0301.JPG

 

Videos:                                                                                                         

Liftoff from remote camera                                                                     Z-24\Flight_Z-24_Nikon.MP4

Rocket free-falling followed by parachute deployment                     Z-24\Z-24_freefall.MP4