What I call my 15 nanoseconds of media fame is related to research I coordinated in Communications Through Plasma During Hypersonic Flight. I’ll explain more below. This research led to my being interviewed for two publications including being quoted in Scientific American.
- Plasma Puzzle, Guy Morris, Aviation Week & Space Technology, p. 58, Mar 30, 2009.
- Piercing the Plasma, Mark Wolverton, Scientific American, p. 28, Dec. 2009. http://www.scientificamerican.com/article/piercing-the-plasma/
At about Mach 10 and above, a high energy plasma field develops around the vehicle. Plasma, sometimes called the fourth state of matter, is when electrons start to dissociate from molecules. A common example is neon in a sign. It is the dissociation that produces the light. Around a vehicle this causes a high attenuation of radio frequencies causing communication blackout. That is, people on the ground are no longer able to communicate with the vehicle. I sometimes call this the electromagnetic version of the sound barrier. The pressures and temperatures (above 5000 C) are enough to start breaking molecules apart (more or less.) This was a known problem for the Galileo and Apollo space missions during re-entry. The Space Shuttle was also sometimes affected by this. I managed several research projects into methods for communicating under these conditions.
FYI. Depending on whom you ask, “hypersonic” means above Mach 6. I tried to coin the phrase “plasmasonic” for when an aircraft is generating plasma, but it didn’t catch on.
Fun fact: The Space Shuttle used to enter the atmosphere at about Mach 26.
Perhaps my biggest accomplishment in this area was to hold a workshop specifically on this topic (funded by the Air Force Office of Scientific Research) with over 30 specialists attending. The main activity was to identify all known possible solutions to the problem and rank them. The intent was to help decide where research dollars should be spent.
- Charles H. Jones, Report From the Workshop on Communications Through Plasma During Hypersonic Flight, held August 2006, Boston, MA; Defense Technical Information Center website: http://handle.dtic.mil/100.2/ADA496640
Other related publications:
- Madhusudhan Kundrapu and Michael Keidart, Department of Mechanical and Aerospace Engineering, The George Washington University; and Charles Jones, Air Force Flight Test Center, Optimum Beam Wavelength for Laser-Based Directed Energy Systems and Electrostatic Mitigation Approach for Uninterrupted Telemetry during Testing, Journal of Directed Energy, Volume 4, Number 2, Winter 2010 http://www.deps.org/store/merchandise/journal.html
- Michael Keidar, Madhusudhan Kundrapu, Minkwan Kim, Iain D. Boyd, Charles H. Jones, and Brian Mork, Approaches To Mitigate Disruption Of Telemetry During Directed Energy Testing, Proc. International Telemetering Conf., Vol. XXXXIV, (2008) Paper 08-07-04.
- Starkey, M. Lewis, and C. Jones, Plasma Telemetry in Hypersonic Flight, Proc. International Telemetering Conf., Vol. XXXVIII, (2002) Paper 02-15-2
- Ryan P. Starkey and Mark J. Lewis, and Charles Jones, Plasma Sheath Characterization for Telemetry in Hypersonic Flight, International Telemetering Conf., Vol. XXXIX, (2003) Paper 03-28-01
- Saravanakanthan Rajendran, Michael Keidar, Iain D. Boyd, Charles H. Jones, and Brian Mork, Modeling of Plasma Formation Due to Laser Irradience During Directed-Energy Testing, Proc. International Telemetering Conf., Vol. XXXXIII, (2007) Paper 07-07-03.
- Charles H. Jones, Recommendations From the Workshop on Communications Through Plasma During Hypersonic Flight, Proc. American Institute of Aeronautics and Astronautics Air Force T&E Days 2009, Paper AIAA-2009-1718.
- Charles H. Jones, Potential Solutions to Communications During Plasmasonic Flight, Proc. International Telemetering Conf., Vol. XXXXV, (2009) Paper 09-18-01.
- Madhusudhan Kundrapu, Michael Keidar and Charles H. Jones, Electrostatic Approach for Mitigation of Communication Attenuation during Directed Energy Testing, Proc. International Telemetering Conf., Vol. XXXXV, (2009) Paper 09-18-04.
- Jones and M. Whelan, Hypersonic Test Instrumentation, International Test & Evaluation Association Workshop, Lancaster, CA (2000)
- Starkey, M. Lewis, and C. Jones, Active FlowField Modification For Plasma Telemetry, International Test & Evaluation Association Workshop, Lancaster, CA (2002)
- Saravanakanthan Rajendran, Michael Keidar, Iain D. Boyd, Charles H. Jones, and Brian Mork, Modeling of Laser Ablation Process During Directed Energy Testing, Proc. International Test & Evaluation Association Workshop, Ridgecrest, CA, (2007).
- Michael Keidar, Minkwan Kim, Iain D. Boyd, Charles H. Jones, and Brian Mork, Disruption Of The Radio Signal Due To Plasma Formation During Directed Energy Testing And Mitigation Approaches, Proc. International Test & Evaluation Association Workshop, Lancaster, CA, (2008).