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Horn, Jennifer R.

Publications and source records attributed to Horn, Jennifer R..

Augmentation of orbital debris shielding for Space Station Freedom

Augmentation concepts for the Space Station Freedom (SSF) are described in detail and advantages and disadvantages of various proposals are evaluated. It is pointed out that early augmentation of SSF debris shielding, which would take place 6-9 years after the First Element Launch, could provide the greatest advantages to the program in terms of weight, cost, and safety benefits. Potential augmentation concepts include an attached, rigid aluminum second bumper; the multi-shock shield concept; a mesh double bumper concept; a debris shield augmentation element; a multi-shock airbag protection concept for 2-10 cm debris; and a debris sweeper. Requirements for and operation and deployment of these concepts are described in detail and an example of the augmentation effect on cumulative SSF probability of no-failure from debris and meteoroid impacts is given. An estimate of predicted encounter rates between debris and a 100 m radius sphere around SSF is presented.

Christiansen, Eric L.↗

Shielding requirements for the Space Station habitability modules

The design, analysis, development, and tests of the total meteoroid/debris protection system for the Space Station Freedom habitability modules, such as the habitation module, the laboratory module, and the node structures, are described. Design requirements are discussed along with development efforts, including a combination of hypervelocity testing and analyses. Computer hydrocode analysis of hypervelocity impact phenomena associated with Space Station habitability structures is covered and the use of optimization techniques, engineering models, and parametric analyses is assessed. Explosive rail gun development efforts and protective capability and damage tolerance of multilayer insulation due to meteoroid/debris impact are considered. It is concluded that anticipated changes in the debris environment definition and requirements will require rescoping the tests and analysis required to develop a protection system.

Avans, Sherman L.↗

An analysis of penetration and ricochet phenomena in oblique hypervelocity impact

An experimental investigation of phenomena associated with the oblique hypervelocity impact of spherical projectiles on multisheet aluminum structures is described. A model that can be employed in the design of meteoroid and space debris protection systems for space structures is developed. The model consists of equations that relate crater and perforation damage of a multisheet structure to parameters such as projectile size, impact velocity, and trajectory obliquity. The equations are obtained through a regression analysis of oblique hypervelocity impact test data. This data shows that the response of a multisheet structure to oblique impact is significantly different from its response to normal hypervelocity impact. It was found that obliquely incident projectiles produce ricochet debris that can severely damage panels or instrumentation located on the exterior of a space structure. Obliquity effects of high-speed impact must, therefore, be considered in the design of any structure exposed to the meteoroid and space debris environment.

Schonberg, William P.↗