Experimental Sounding Rocket Workshops

Update 5/27/09: No Workshop Before Competition: Due to the problems with the Tropos 2 hybrid rocket, we will not hold the Experimental Sounding Rocket Workshop before the Competition. In the next few weeks, we will continue to experiment with the igniters and conduct another motor static firing. This firing will use a horizontal "trapeze" type test stand to better measure thrust. We also hope to conduct a static test at the Competition as a demonstration (and to gather additional data). Once the propulsion issues are corrected, we will rebuild the Tropos 2 in the summer/fall.

Update 4/28/09: Disappointing Flight of Tropos 2 Hybrid Rocket: ESRA and the Utah State University Experimental Sounding Rocket Club launched the "Tropos 2" hybrid rocket on April 25th. We had ignition troubles from the start, and on the third attempt, the rocket lifted off. But it didn't develop full thrust, climbed relatively slowly, and nosed over and flew more or less horizontally at an altitude of about 200 feet before impacting at a shallow angle about 500 feet from the launcher. The recovery sequence started, but didn't have enough time or altitude to fully deploy. The airframe and avionics were destroyed, but the parachutes, oxidizer tank, plumbing, and motor were mostly undamaged. Postflight examination showed that only 1/3 of the fuel was consumed. We believe it is due to a single igniter not being energetic enough to quickly, fully, and reliably ignite the motor (we used two igniters on the first attempt but only one fired--more details are on the Tropos 2 page). We plan to redesign the igniters and may do another static firing soon. But rebuilding the airframe will take longer.

Update 4/14/09: Successful Static Firing of "Tropos 2" Hybrid Motor: ESRA and students from the Utah State University Experimental Sounding Rocket Club successfully fired the caramel/nitrous oxide hybrid motor for the "Tropos 2" rocket being developed for future Experimental Sounding Rocket Workshops. The motor developed approximately 170 pounds of thrust and burned for approximately 17 seconds (with significant thrust--it burned much longer as the nitrous blew down). This successful test paves the way for a planned launch of the Tropos 2 on April 25th in Utah's west desert.

Update 2/17/09: A Workshop is tentatively planned for June 2009, immediately before the 4th IREC. The Tropos 2 rocket is being built and major tests will commence soon. A Workshop may be held depending on interest and success of the Tropos 2 test program.

Overview

ESRA conducts Experimental Sounding Rocket Workshops for college teams interested in starting a rocket program for participation in the launch competitions. At these workshops, students and faculty members are shown the design process and rationale behind the “Tropos” series of hybrid rockets.

In the workshop, the participants learn to do basic performance calculations, how to use software to do more sophisticated analysis, how to manufacture various rocket components (nozzles, nose cones, etc.), how to pack parachutes, and how to cast a hybrid motor. They also learn how to load the nitrous oxide oxidizer and conduct a static motor firing. And finally, they get to travel to a launch site and launch the Tropos.

First Experimental Sounding Rocket Workshop (2006)

Details on the First Workshop can be found here.

Second Experimental Sounding Rocket Workshop (2009)

The Second Experimental Sounding Rocket Workshop is tentatively scheduled for June 22-24, 2009, right before the 4th IREC. The plan is to have the workshop on the Monday through Wednesday before the competition, drive to Green River on Wednesday night, and then launch the workshop rocket on the first day of the competition (Thursday) as a non-competing demonstration launch. Then workshop participants are welcome to watch the rest of the competition as they desire.

The workshop will show how to build the latest in the Tropos series, the Tropos 2. This rocket will use a nitrous oxide/caramel hybrid motor, and should be less expensive and easier to build than the Tropos 1. The overall airframe is expected to be about 8 feet long and 8 inches in diameter. While the goal was to have parts and materials costs for the Tropos 1 less than $1500, the goal for the Tropos 2. will be less than $1000, with less machining required as well.

Tentative Schedule

Monday, June 22, 2009

8:00     Welcome/Intro
9:00     Basics of Experimental Sounding Rockets/Hybrid Demo
9:45     Break
10:00   Tropos 2 Overview
11:00   Tropos 2 Motor Design

Noon Lunch Discussion: Regulatory Issues and Safety

1:00 Tropos 2 Motor Casting
3:00 Composites Manufacturing: Tropos 2 Nosecone or Boattail Layup

6:00 Dinner/Social

Tuesday, June 23, 2009

8:00     Overall Design Approach/Sequence of Major Tests
9:00     Flight Performance/Stability
9:45     Break
10:00   Propulsion Calculations
11:00   Tropos 2 Oxidizer System and Injector

12:00 Lunch Discussion: Different Ways to Run a Student Program

1:00     Tropos 2 Fuselage Assembly and Mounting on Launch Rail
3:00     Oxidizer/Injector Flow Test
5:00     Install Motor

5:30    Break for Dinner (on your own)
7:00     Meet Back at Shop, Transport Launch Rail to Airport
8:30     Motor Static Firing at Logan/Cache Airport

Wednesday, June 24, 2009