Multi-wavelength Laser Backscatter Measurements of LOX-Kerosene Rocket Plumes

Abstract

The Ballistic Missile Defense Organization's (BMDO) Innovative Science and Technology Experimentation Facility (ISTEF(1)) is located on the Kennedy Space Center at Cape Canaveral Florida. The ISTEF conducts research and development in the area of passive and active electro-optical science and technology for missile defense and its location provides a unique opportunity to observe a large number of rocket launches. Atlas II first stage engines use LOX-kerosene as the propellant and are representative of a number of tactical and theater ballistic missiles. Incomplete (non-stoichiometric) combustion of LOX-kerosene leads to soot formation, the presence of which could be a useful threat discriminant or identifier. The concentration and size of the soot particles is extremely important when modeling the signature from LOX-kerosene plumes. Previously, ISTEF measured the laser radar cross sections of LOX-kerosene plumes in the visible and NIR. This paper reports the results of follow-on measurements, which greatly improve the accuracy and sensitivity of the previous measurements. To our knowledge these are the only multi-wavelength, in-situ measurements of laser-radar cross sections of LOX-kerosene plumes. Absolute (calibrated) laser radar cross sections of both the plume and hardbody were measured at wavelengths of 532nm and 1064nm simultaneously at altitudes ranging from 1km to 20km. Significant variation between the visible and NIR laser radar cross sections as a function of altitude was measured which implies that the particle size distribution has a strong dependence on altitude. The laser illuminator was a frequency doubled pulsed Nd:YAG transmitting at both 532nm and 1064nm with a pulse width of 10ns and repetition rate of 10Hz, and the laser backscatter receiver was a 0.5 meter telescope with APD detectors.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1999
Accession Number
ADA390081

Entities

People

  • Andrew Grunke
  • Brad Griffis
  • John Streyjewski
  • Joseph Salg
  • Michael Lovern

Tags

Communities of Interest

  • Advanced Electronics
  • Sensors
  • Weapons Technologies

DTIC Thesaurus Topics

  • Altitude
  • Backscattering
  • Ballistic Missiles
  • Detectors
  • Electromagnetic Scattering
  • Laser Beams
  • Laser Radar
  • Lasers
  • Measurement
  • Particle Size
  • Particles
  • Passive Sensors
  • Propellants
  • Radar Cross Sections
  • Recording Systems
  • Reflectance
  • Repetition Rate

Fields of Study

  • Physics

Readers

  • Missile Defense Systems.
  • Molecular Photonics/Laser Physics
  • Spectroscopy.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers
  • Space
  • Space - Hall-Effect Thruster
  • Space - Space Objects