This is my first attempt at a 2 stage rocket using my home made "Sugar" propellant rocket motors. This is basically a test of the ability to do an in flight ignition of a motor.
Above is the rocket used for the 2 stage Launch test. The body is my standard 3" PVC, plastic fins heat welded and epoxied to the body and a wood nose cone.
I used two of my home made 555 timers for this launch. The first timer was located in the booster section and set for 3.5 seconds. The second timer was in the sustainer section and set to deploy the parachute 8 seconds after separation.
The motors were two small 1"x9" grain, KNO3/Sugar 65%/35%. The lower booster stage is an old motor section that had seen a number of flights and was at the end of its useful life. I decided to just let the booster free fall/tumble as a means of recovery. With the large fins and being an unstable object I assumed it should land reasonably soft.
Here is the liftoff of LT-23. Good ignition and liftoff.
Here is the ignition of the second stage right on time. I should have set the timer slightly sooner, as the rocket was starting to arc over at this time. The dark spot circled is the motor exhaust at ignition.
Here you can see the trail as the rocket passes through (of course) the only cloud in the area. Visual contact was maintained with the rocket for the entire flight, although video resolution was to poor for images.
The parachute deployment charge went off at the set 8 seconds, however, the deployment charge burned through the line and the rocket body came to earth seeking a core sample. I used a very cheap polypropylene rope, and I knew it was risky, but I was out of my good braided nylon. At any rate the rocket landed in a grassy area of the deserted farm. Again, it figures, I have 630 acres of open farm ground, without a bit of vegetation and the rocket lands in tall grass!
The nose cone and parachute were another matter. The parachute floated gracefully with just the weight of the nose cone. I didn't think it was ever coming down. I think it was riding the thermals created by the sun heating the dark soil. The parachute was still in the air after I had walked about a 1/4 mile in search of the rocket main body. It stayed in the air between 10 and 15 minutes.
Here is a photo of the upper section of the rocket buried a foot in the ground.
Here I am trying to pull out the upper section from the ground, believe me. It was no easy task!
Finally, its out. Look at how far in the ground it was buried!
Here's my core sample, it took another 15 minutes to poke all the dirt out. Amazingly, both sections of the rocket were completely undamaged. The only damage I could find was a small dent in the 9 volt battery.
Here I bring in the nose cone and parachute, they were over 3/4 mile from the launch site.
In retrospect it was a good flight, a little quicker timing on the sustainer would be in order. If it had not been for the cheap rope used on the recovery line, the recovery would have been perfect. The air start of the sustainer motor was successful, and the rocket was recovered virtually undamaged.
Click here for a video of the flight. Warning: Rated PG 13 for language!
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