Accession Number:

ADA390081

Title:

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

Descriptive Note:

Corporate Author:

NICHOLS RESEARCH CORP ARLINGTON VA

Report Date:

1999-02-01

Pagination or Media Count:

21.0

Abstract:

The Ballistic Missile Defense Organizations BMDO Innovative Science and Technology Experimentation Facility ISTEF1 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 NdYAG 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.

Subject Categories:

  • Antimissile Defense Systems
  • Liquid Rocket Propellants

Distribution Statement:

APPROVED FOR PUBLIC RELEASE