Jennifer Kitaygorsky

Spacecraft and launch vehicles especially face some unique environmental EMC challenges, which will be discussed in this talk.

Lightning is a threat to launch vehicles not only when there’s a nearby thunderstorm. In fact, it is far more likely for a launch vehicle to trigger lightning – which is caused by the presence of the vehicle itself and often occurs in the absence of naturally occurring lightning.

Lightning avoidance criteria were developed and gradually improved due to the lightning strikes to Apollo 12 and Atlas-Centaur 67 (AC-67) launch vehicles. The Apollo 12 mission was launched on November 14, 1969, from launch pad 39A at the Kennedy Space Center, triggering lightning and causing major electrical disturbances 37.5 and 52 seconds into the flight. The AC-67 was launched on March 26, 1987, from the Eastern Test Range. The vehicle triggered lightning at 49 seconds into the flight, resulting in the loss of the vehicle.

The lightning avoidance criteria rules generally work well to prevent triggered lightning, but they put expensive constraints on launches and missions. As launches become more ubiquitous it may be time to think about lightning protection of launch vehicles as opposed to following strict lightning avoidance rules. This talk will present the unique challenges of lightning protection for launch vehicles.

Static electricity can be another challenge to reusable launch vehicles. The launch vehicle will triboelectrically charge to a large potential if flown through clouds. During flight the vehicle potential becomes high enough that the vehicle will start to discharge through extremities, causing RF interference with antennas. Commercial aircraft easily avoid this problem by strategic placement of static wicks at vehicle extremities. The static wicks may not be a good solution for launch vehicles.

Finally, the concept of spacecraft charging due to high energy electrons in orbit will be presented, and mitigation techniques will be discussed.

Biography:

Jennifer Kitaygorsky is a Principal Scientist at Electro Magnetic Applications (EMA). She manages projects, consults and supports aerospace integrators in areas of electromagnetic environmental effects (E3), EMI, EMC, and EME. She has extensive experience in computational electromagnetics (CEM), as well as specialized testing/measurements.