BlazingAngel665
Propulsion Lead, Agile Space Industries
- Joined
- Nov 17, 2015
- Messages
- 87
- Reaction score
- 3
Brief background, I grew up in Kansas. There wasn't a NAR or Tripoli group nearby, so I did things solo. I started with monthly runs to a hobby shop about an hour and a half away to pick up packs of Estes motors. Eventually I started doing custom propulsion. I did this for about three years. I realized that my large field and lack of neighbors was about to go away and needed to find a club to fly with. This meant getting certified.
This story starts in June after my first supersonic flight. I decided I had reached the limits of my phenolic tube and balsa wood roots and that I needed an all fiberglass rocket. My first stop was OpenRocket. By that evening I had a roughed in blueprint for a rocket.
(Ignore the buggy CoG calculation, it thought my booster section was massless at the time)
The design was based upon Madcow Rocketrys excellent Black Brant II. Im a big fan of the boat tail on this rocket. The thin walled fiberglass tubing was also excellent quality. I am less of a fan of the conical nose cone, so I replaced the nose cone with a 4:1 ogive one. My next change was to stretch the fuselage to accommodate the longest 38mm motors. The airframe is now long enough for a 6GXL case and a drogue. Finally an avionics bay and forward fuselage made the rocket even taller and added dual-deployment capability. With the design complete, orders went out to Madcow Rocketry, Apogee Components, and Amazon.
Over the next week parts began to trickle in. My room began to look suspiciously like the Vehicle Assembly Building. Unfortunately, life intervened at this point in time, and I only had a few free weekends before September. I assembled the motor mount, but that was all. As I left for college my rocket parts migrated with me. I joined MIT's rocket team. We go out to Amesbury, MA and Burwick, ME, for launches.
With the first team launch quickly approaching, I needed a rocket. With a few tubes of 5 minute epoxy, a box of parts, and some good friends I entered the workshop at 1 pm.
I walked out ten and a half hours later, carrying a flyable, but still very incomplete rocket.
I borrowed electronics from Rocket Team. The first flight had a Marsa 54L and a Stratologger CF. The parachute is a 30in nylon chute. I'm not in love with the final decent rate of about 10m/s. It seems too fast. One of these days I'll put a larger chute on the vehicle. The drogue is a 12in.
The rocket flew under the pseudonym Albino Beaver in homage to its semi-transparent body and MITs mascot. A picture perfect flight sent the vehicle to 1050ft. A bystander was kind enough to video the launch and find me on the internet to share the footage. That video is [video=youtube;ivNKMSJnqeU]https://www.youtube.com/watch?v=ivNKMSJnqeU&index=1&list=FLgBqAFriBrftRkj304eiiVw[/video]. Or a picture:
Unfortunately, my fin application didnt survive the landing. One fin popped out. It was a quick fix, but I decided to reinforce all the fins with a fiberglass overlay.
In theory, overlays are awesome, but in practice, I need practice. My overlay turned out so ugly that three coats of bondo, five coats of primer, and four weekends worth of sanding were required to restore the rocket to a presentable state.
With the fins firmly attached, I turned my attention to the electronics suite. The original av bay was a piece of balsa wood with a circuit board zip tied on one side and a battery on the other side. This sufficed for a mid-power flight, but was insufficient for anything more powerful. To remedy the av bay I added a camera, a backup battery, an arming switch, and connectors to the avionics bay. This all attached to a 3D printed sled.
The Arduino Uno underneath the red flag is an avionics payload that is preparing for a test flight. It sends back live telemetry via an Xbee wireless radio. It will be tagging along on my next flight.
The camera is an 808 #25. It runs about $11 from various online retailers. It is light and cheap, but Im underwhelmed by its behavior. Sometimes it decides to take an unscheduled day off. Other days it works fine. I highly recommend the Marsa. Its easy to use and very functional. The Stratologger is a mainstay of the hobby, probably due to its reliability. On my rocket its purpose is purely as a redundant backup. Power comes from 2 9v batteries. The Stratologger gets one to itself, to make sure I get my rocket back. The Marsa, GPS, and transmitter share the other.
The red flag itself is one of my favorite features. A small microswitch is held by the sled. The switch is wired as normally closed. Two washers create a small channel for the pin attached to the flag. When the pin is inserted, the switch opens, deactivating the Marsa and the Stratologger. This system allows me to keep the pyros off and disarmed until the rocket is ready to launch. The remove before flight tag makes the whole system look and feel professional, despite being mostly cobbled together.
This is the whole rocket laid out on the integration table. Its ready to fly. The only thing left to do is to give it a name and a paint scheme. Hopefully, I can be slightly more creative than on my first attempt.
(Flight Ready)
What do you think guys? I'm taking her out for the third time this Saturday. I'm aiming to get my L1 cert if the fins will stay on. (trapezoidal fins, I know, but these look so nice)
This story starts in June after my first supersonic flight. I decided I had reached the limits of my phenolic tube and balsa wood roots and that I needed an all fiberglass rocket. My first stop was OpenRocket. By that evening I had a roughed in blueprint for a rocket.
(Ignore the buggy CoG calculation, it thought my booster section was massless at the time)
The design was based upon Madcow Rocketrys excellent Black Brant II. Im a big fan of the boat tail on this rocket. The thin walled fiberglass tubing was also excellent quality. I am less of a fan of the conical nose cone, so I replaced the nose cone with a 4:1 ogive one. My next change was to stretch the fuselage to accommodate the longest 38mm motors. The airframe is now long enough for a 6GXL case and a drogue. Finally an avionics bay and forward fuselage made the rocket even taller and added dual-deployment capability. With the design complete, orders went out to Madcow Rocketry, Apogee Components, and Amazon.
Over the next week parts began to trickle in. My room began to look suspiciously like the Vehicle Assembly Building. Unfortunately, life intervened at this point in time, and I only had a few free weekends before September. I assembled the motor mount, but that was all. As I left for college my rocket parts migrated with me. I joined MIT's rocket team. We go out to Amesbury, MA and Burwick, ME, for launches.
With the first team launch quickly approaching, I needed a rocket. With a few tubes of 5 minute epoxy, a box of parts, and some good friends I entered the workshop at 1 pm.
I walked out ten and a half hours later, carrying a flyable, but still very incomplete rocket.
The rocket flew under the pseudonym Albino Beaver in homage to its semi-transparent body and MITs mascot. A picture perfect flight sent the vehicle to 1050ft. A bystander was kind enough to video the launch and find me on the internet to share the footage. That video is [video=youtube;ivNKMSJnqeU]https://www.youtube.com/watch?v=ivNKMSJnqeU&index=1&list=FLgBqAFriBrftRkj304eiiVw[/video]. Or a picture:
In theory, overlays are awesome, but in practice, I need practice. My overlay turned out so ugly that three coats of bondo, five coats of primer, and four weekends worth of sanding were required to restore the rocket to a presentable state.
With the fins firmly attached, I turned my attention to the electronics suite. The original av bay was a piece of balsa wood with a circuit board zip tied on one side and a battery on the other side. This sufficed for a mid-power flight, but was insufficient for anything more powerful. To remedy the av bay I added a camera, a backup battery, an arming switch, and connectors to the avionics bay. This all attached to a 3D printed sled.
The camera is an 808 #25. It runs about $11 from various online retailers. It is light and cheap, but Im underwhelmed by its behavior. Sometimes it decides to take an unscheduled day off. Other days it works fine. I highly recommend the Marsa. Its easy to use and very functional. The Stratologger is a mainstay of the hobby, probably due to its reliability. On my rocket its purpose is purely as a redundant backup. Power comes from 2 9v batteries. The Stratologger gets one to itself, to make sure I get my rocket back. The Marsa, GPS, and transmitter share the other.
The red flag itself is one of my favorite features. A small microswitch is held by the sled. The switch is wired as normally closed. Two washers create a small channel for the pin attached to the flag. When the pin is inserted, the switch opens, deactivating the Marsa and the Stratologger. This system allows me to keep the pyros off and disarmed until the rocket is ready to launch. The remove before flight tag makes the whole system look and feel professional, despite being mostly cobbled together.
This is the whole rocket laid out on the integration table. Its ready to fly. The only thing left to do is to give it a name and a paint scheme. Hopefully, I can be slightly more creative than on my first attempt.
What do you think guys? I'm taking her out for the third time this Saturday. I'm aiming to get my L1 cert if the fins will stay on. (trapezoidal fins, I know, but these look so nice)