Basic Information

Name

DS-1

Launch date:

28 November, 2015

Rocket description

- 58mm glass-epoxy airframe

- 4 fins, glass-epoxy

- maple elliptical nosecone

- 24 in. circular parachute

Payload

- Raven altimeter

- BRB900 GPS transmitter

- outboard mounted microcamcorder

Liftoff mass

1.900 kg.

Flight objectives

- First flight of DS rocket;
- Confirm flight operation of new deployment system

 

Motor details

Motor name

Impulser

Propellant

KNSB

Grain mass

268 grams

Nominal impulse

316 N-sec

Class

H

 

Additional information

-        Stability Margin = 2.75 (initial)

-        Impulser-X casing used (Impulser casing lost in Flight Z-22 incident)

 

Weather conditions

Temperature

-8°C

Wind

SW 5 km/hr

Sky

Clear, bright sun

Other

Humidity 67%

Ceiling

unlimited

 

Launch Event Description

Setup of the rocket went smoothly with one glitch. The BRB receiver did not show GPS indication after BRB transmitter powered up. The transmitter was re-started and after an unusually long delay, the receiver finally showed GPS reception. I used the hand-held camcorder (with scope tube) to attempt to film the complete flight. A second tripod-mounted camcorder was used to film the liftoff. After verifying the sky was clear, the countdown proceeded. About a second after ignition switch was closed, the rocket soared off the pad, climbing straight upward. The motor burned for about 2 seconds and the rocket was visible part of the way to apogee. The sun glinting off the rocket was noticed a couple of time during the climb to apogee. A “pop” sound of the apogee charge was heard after a short while and the smoke cloud from the pyro charge was clearly seen, illuminated by the sun against the deep blue sky. The rocket was not sighted until a second ‘pop’ sound was heard as the chute pyro fired. We spotted the rocket descending nicely by parachute, and after about a half minute, the rocket gently touched down about a thousand feet away. We then proceeded to enter the BRB GPS coordinates into the hand-held GPS unit. Landing site was indicated as 0.15 miles away. When we reached the touchdown site, we saw that the rocket appeared to be in perfect condition after this maiden flight. Raven beeped out an apogee of 2682 feet.

 

Flight Analysis

Event:

Time (sec)

feet

metres

Apogee

12.75

2681

817

Separation

13.92

2665

812

Main deployment

44.08

523

159

Touchdown

60.93

-

-

Range

-

1102

336

Descent rates:

ft./sec.

m/sec.

 

Free-fall

73.4

22.4

 

Main parachute

29.6

9.02

 

 

Post-flight analysis and comments:

Post-flight examination confirmed that the rocket was overall in great shape except for one missing launch lug. Examination of the motor, however, revealed an anomaly. The motor casing had suffered a burn-through, approximately 1x2 cm, toward the nozzle end. The aft rocket body section suffered some minor heat damage as a result. Apparently, the burn-through was a result of using the longer Impulser-X casing, with greater space between the four grain segments (Impulser-X holds 5 segments). The grain spacers were 27.5mm, compared to typical 10mm spacing.

 

Raven baro and accelerometer graph:                                                

Barometric and axial acceleration data                                                 DS-1\DS-1_Raven.jpg

 

Big Red Bee

Launch and landing locations with flight path                                       DS-1\DS-1_BRB.jpg         

 

Photos:                                                                                                         

Rocket on pad                                                                                              DS-1\DSCN0250a.JPG

Liftoff and ascent                                                                                        DS-1\DS-1_ascent_capture.jpg

                                                                                                                        DS-1\DS-1_ascent1.jpg

                                                                                                                        DS-1\DS-1_ascent2.jpg

                                                                                                                        DS-1\DS-1_ascent3.jpg

                                                                                                                        DS-1\DS-1_ascent4.jpg

Descending by parachute                                                                          DS-1\DS-1_chute_capture.jpg

                                                                                                                        DS-1\DS-1_near_touchdown.jpg

Rocket at touchdown site                                                                         DS-1\DSCN0256a.JPG

                                                                                                                        DS-1\DSCN0258a.JPG

Motor casing burnthrough                                                                        DS-1\ds-1_003a.jpg

 

Video:                                                                                                           

Liftoff viewed from tripod camera                                                          DS-1\DS-1_tripod_camera.MP4