Article 1561
By Peter Schurke, November 2009
 

Dateline:  Seattle—November, 2009

Fresh off of an incredible year in the Team America Rocketry Challenge, the budding rocket engineers at Seattle’s Ingraham High School are taking on a new challenge:  Designing rockets for NASA!

Last year, all three teams from a small academy program within Ingraham High School—the Ingraham Aerospace Sciences Academy (IASA)—were the only teams from the Northwest to make it to the finals of the Team America Rocketry Challenge (TARC).  The smallest and youngest of the three teams, Team Charlie, had an incredible day and finished in seventh place—earning the IASA an invitation to submit a proposal to participate in NASA’s Student Launch Initiative in 2009-2010.

A dedicated group of ten returning students worked hard to put together a detailed proposal for a science project and a re-usable rocket.  They submitted their proposal on October 1st, and received notification from NASA on October 22nd that their proposal had been accepted.  They are now working on a detailed preliminary design for their Preliminary Design Review (PDR) which is due to NASA on December 5th, 2009.

The requirements of the SLI project are as follows:

  • The vehicle shall carry a student-designed science payload.
  • The vehicle shall be developed so that it delivers the science payload to a specific altitude of 5,280 feet AGL.
  • The vehicle shall be designed to use a standard launch rail.
  • For new teams (us), the maximum total motor impulse provided by the entire vehicle shall not exceed 2560 Newton-seconds (K-class).  This total impulse constraint is applicable to any combination of single, clustered, or staged motors.
  • The vehicle shall use solid motor propulsion using ammonium perchlorate composite propellant (APCP) motors.  Teams will have a choice of motors from which to choose.
  • The launch vehicle and science project shall be designed to be recoverable and reusable.
  • Separation at apogee will be allowed, but not advised because main deployment at apogee increases the risk of drifting outside the recovery area.  Exception:  Separating at apogee to deploy a drogue parachute.  Dual deployment and shear pins are encouraged.
  • Rockets should not be so complicated that preparation of the vehicle and payload on launch day shall exceed 4 hours.  At the end of the 4 hour preparation period, the team must be prepared to launch.
  • All vehicle and payload components will be designed to land on the field within the square mile of recovery area.
  • Rockets should not have time-critical experiments.  Payloads with electronics or recorders must be able to sit on the launch pad for up to an hour before launch to accommodate possible range and weather delays.
  • Rockets will be launched from a standard firing system that does not require additional circuitry or special ground support equipment to initiate the flight or complicate a normal 10 second countdown.
  • Data from the science project shall be collected, analyzed, and reported by the team following the scientific method.
  • A tracking device shall be placed on or in the vehicle allowing the rocket and payload to be recovered after launch.
  • A scale model of the team’s proposed vehicle must be constructed and flown prior to the Critical Design Review (CDR) to verify the flightworthiness of the design.
  • All teams must successfully launch their full-scale rocket prior to Flight Readiness Review (FRR).  The purpose is to verify the vehicle structure and recovery systems and the team’s performance.  A flight certification form will be filled out by an L2 or higher NAR/TRA observer.
  • The following items may not be used in building the rocket:
    • No flashbulbs.  The recovery system must use commercially available low-current electric matches.
    • No forward canards.
    • No mach-busters.
    • No forward-firing motors.
    • No rear-ejection parachute designs.
  • An Educational Engagement plan must include at least two projects that engage a combined total of 75 or more younger students in rocketry.  Comprehensive feedback on the activity must be developed and submitted.

Some specifics on “Project:  Rainier”

A copy of the team’s proposal is available at our website:  www.ingrahamrocketry.org/sli.html

(Disclaimer:  the website is still extremely elementary.  Increased sophistication is in progress…trust me).  Updates will be made as the project progresses.

As their science project, the students chose to place a large stabilizing gyroscope at the vehicle’s approximate center of mass and measure how effectively (or not) the gyroscope “fights the ambient forces that attempt to deviate the rocket’s attitude from straight up”.  Because the gyroscope does not actively control any of the flight surfaces it is technically classified as “passive stabilization”.

Dual-redundant altimeters are planned to control deployment of a drogue at apogee and a main at a yet-to-be-selected altitude.  An accelerometer-based altimeter will be used as the primary deployment altimeter for sensing apogee, while a barometric-based altimeter will be used as the backup deployment system.  This arrangement utilizing two different altimeters with two different failure modes was chosen to increase reliability of the deployment system.

 A third altimeter for gathering accelerometer and barometric data and a GPS telemetry system is planned, and will be placed in the nose cone of the vehicle.  The nose cone bulkhead will then be shielded to prevent signals from the transmitter from interfering with the deployment systems.  This will allow the students to capture telemetry data in real time, as well as the data stored on the altimeters; the GPS will also serve as the required tracking device.

 The rocket will be intentionally designed so that when fully loaded it will be at the minimum end of the stability range.  This will give the students the ability to fly control flights with the gyroscope inactive while also giving them the greatest possible opportunity to sense an increase in overall stability when the gyroscope is active.

 At this time, we are in the process of selecting and ordering parts, designing an electronics package for sensing, measuring, and logging the effect of the gyroscope on the flights of the vehicle, and refining the overall design of the vehicle.

 Updates will be periodically posted to the team’s website, as well as sent to the new (and absolutely gorgeous) Northwest Rocketry website.