Strikeshield lightning ground

[Fred Ficarra]

The man is a fraud.

Regardless of our opinions about the cause and affect of lightening, I agree with every word Arlyn said about Thompson.Oh, thanks Gord.

 

[Gord May]

Not Dr. Gord

Yes, Dr. Thomson is now in private enterprise, but he has a little bit of legitimate scientific background, unlike Gord & Fred & Alryn.Curriculum Vitae: Ewen McKenzie ThomsonEducation Ph.D., Electrical Engineering, University of Queensland, Australia, 1985; Thesis: Lightning in Papua New Guinea Abstract M.Sc. (Honors), Physics, University of Auckland, New Zealand, 1973; Thesis: RF Characteristics of Lightning Abstract B.Sc., University of Auckland, New Zealand, 1971 High school - Kings College (Dux), Auckland, 1963-1967Employment history2001- present President & CEO Marine Lightning Protection Inc.1986- 2003 Associate Professor in Electrical Engineering, University of Florida1985-1986 Assistant Professor in Electrical Engineering, University of Florida1982-1984 Provisional Visiting Assistant Professor in Electrical Engineering, University of Florida1981-1982 Research Assistant in Electrical Engineering, University of Florida1978-1980 Lecturer 1, Physics Department, University of Papua New Guinea, Papua New Guinea1974-1977 Senior tutor, Physics Department, University of Papua New Guinea, Papua New Guinea1973 High School Teacher, Science Department, St. Peters College, Auckland, New Zealand Curriculum Vitae: Ewen ThomsonPersonalName: Ewen McKenzie ThomsonAddress: 3215 NW 17th Street, Gainesville, Florida, 32605-2511Phone: (352) 373-3485FAX: (352) 373-3485E-mail: thomson@marinelightning.comURL: http://www.marinelightning.comBiographical Age 53, born in Otahuhu, New Zealand, Married, US Permanent ResidentEducation Ph.D., Electrical Engineering, University of Queensland, Australia, 1985; Thesis: Lightning in Papua New Guinea Abstract M.Sc. (Honors), Physics, University of Auckland, New Zealand, 1973; Thesis: RF Characteristics of Lightning Abstract B.Sc., University of Auckland, New Zealand, 1971 High school - Kings College (Dux), Auckland, 1963-1967Employment history2001- present President & CEO Marine Lightning Protection Inc.1986- 2003 Associate Professor in Electrical Engineering, University of Florida1985-1986 Assistant Professor in Electrical Engineering, University of Florida1982-1984 Provisional Visiting Assistant Professor in Electrical Engineering, University of Florida1981-1982 Research Assistant in Electrical Engineering, University of Florida1978-1980 Lecturer 1, Physics Department, University of Papua New Guinea, Papua New Guinea1974-1977 Senior tutor, Physics Department, University of Papua New Guinea, Papua New Guinea1973 High School Teacher, Science Department, St. Peters College, Auckland, New ZealandProfessional Societies American Geophysical Union, Institute of Electrical and Electronic Engineers, Lightning Protection InstituteHonors: NASA Certificate of Recognition, 1996 & 1997; Research Achievement Award, University of Florida, 1992; Supervisor Outstanding Undergraduate Research Project in Electrical Engineering, 1988; Outstanding Supervisor of an Undergraduate Core Laboratory, 1987; Supervisor Outstanding Master's Thesis in Electrical Engineering, 1987; Supervisor Outstanding Undergraduate Research Project inElectrical Engineering, 1984 Postgraduate Scholarship, University of Auckland, 1973; Physics Prize, University of Auckland, 1973. Curriculum Vitae: Ewen ThomsonPersonalName: Ewen McKenzie ThomsonAddress: 3215 NW 17th Street, Gainesville, Florida, 32605-2511Phone: (352) 373-3485FAX: (352) 373-3485E-mail: thomson@marinelightning.comURL: http://www.marinelightning.comBiographical Age 53, born in Otahuhu, New Zealand, Married, US Permanent ResidentEducation Ph.D., Electrical Engineering, University of Queensland, Australia, 1985; Thesis: Lightning in Papua New Guinea Abstract M.Sc. (Honors), Physics, University of Auckland, New Zealand, 1973; Thesis: RF Characteristics of Lightning Abstract B.Sc., University of Auckland, New Zealand, 1971 High school - Kings College (Dux), Auckland, 1963-1967Employment history2001- present President & CEO Marine Lightning Protection Inc.1986- 2003 Associate Professor in Electrical Engineering, University of Florida1985-1986 Assistant Professor in Electrical Engineering, University of Florida1982-1984 Provisional Visiting Assistant Professor in Electrical Engineering, University of Florida1981-1982 Research Assistant in Electrical Engineering, University of Florida1978-1980 Lecturer 1, Physics Department, University of Papua New Guinea, Papua New Guinea1974-1977 Senior tutor, Physics Department, University of Papua New Guinea, Papua New Guinea1973 High School Teacher, Science Department, St. Peters College, Auckland, New ZealandProfessional Societies American Geophysical Union, Institute of Electrical and Electronic Engineers, Lightning Protection InstituteHonors: NASA Certificate of Recognition, 1996 & 1997; Research Achievement Award, University of Florida, 1992; Supervisor Outstanding Undergraduate Research Project in Electrical Engineering, 1988; Outstanding Supervisor of an Undergraduate Core Laboratory, 1987; Supervisor Outstanding Master's Thesis in Electrical Engineering, 1987; Supervisor Outstanding Undergraduate Research Project inElectrical Engineering, 1984 Postgraduate Scholarship, University of Auckland, 1973; Physics Prize, University of Auckland, 1973.Courses taught at University of Florida Circuits I (EEL3111), Circuits for non-EE majors (EEL3003), Electromagnetic Fields I & II (EEL3472, EEL3473), Lightning (EEL5490), Electromagnetic Fields and Applications I & II (EEL6486, EEL6487)Major Research Projects1. Lightning protection of boats Promoting lightning protection of boats through IBEX, workshops, and web page http://www.thomson.ece.ufl.edu/lightning/. Developing alternative theory to existing ground resistance to explain and predict sideflash formation. Earlier work was based on a resistive model for ground resistance and resulted in a video and publication directed at the lay person.2. Electromagnetic theory Extension of fundamental EM theory (Thomson, 2000; Thomson, 1999; Thomson, 1985; Thomson et al.,1985) applied to lightning modeling.3. Models for sources of dE/dt Analyzing data obtained with the Kennedy Space Center multiple station wideband electric field system (MSWEFS) to develop physical models for the sources of dE/dt. The experimental design, described in Thomson et al. (1994), followed earlier systems; (i) for measuring horizontal electric fields (Thomson et al., 1988a,1988b); (ii) for investigation of lightning characteristics in Papua New Guinea (Thomson, 1980a; 1980b; 1978), and; (iii) for testing a design for a ground flash counter (Clegg and Thomson, 1978)Publicationsa. ReviewedThomson, E.M., Concerning Charge and Current Distributions on a Propagating Lightning Channel Expressed in Retarded Time, IEEE Trans. Electromag. Comp., under revision. Davis, S.M., and E.M. Thomson, Leaders and return stroke fine structure in new terminations to ground in subsequent strokes, J, Geophys. Res., under revision. Thomson,E.M., Exact Expressions for Electric and Magnetic Field from a Propagating Lightning Channel with Arbitrary Orientation, J. Geophys. Res, 104, no.D18, 22293-22300, 1999. Thomson,E.M., Location of sources of radiation using a weighted hyperbola technique, NASA Tech. Briefs, 22, 64, 1998. Medelius, P. J., Y. Yariv, E.M. Thomson, and S. Davis, Frequency and phase compensation in a pulse transmission system, 21, 54, NASA Tech. Briefs, 1997.Thomson, E.M., P.J. Medelius, and S.Davis System for locating the sources of wideband dE/dt from lightning, J. Geophys. Res., 99, No D11, 22.793-22,802, 1994.Thomson, E.M., Lightning and sailboats, SGEB-17, Florida Sea Grant College Program Publication, 1992.. Georgiadis, N., M. Rubinstein, M. A. Uman, P. J. Medelius, and E. M. Thomson, Lightning-Induced Voltages at Both Ends of a 448-m Power Distribution Line, IEEE Trans Electromag. Comp., 34, 451-460, 1992. Thomson, E.M., A critical assessment of the US code for lightning protection of boats, IEEE Trans. Electromag. Comp., 33 (2), 132-138,1991. Rubinstein, M., A.Y. Tzeng, M.A. Uman, P.J. Medelius and E.M. Thomson, An experimental test of a theory of lightning-induced voltages on an overhead wire, IEEE Trans. EMC, 31 (4), 376-383, 1989.Bils, J.R., E.M. Thomson, M.A. Uman, D. and Mackerras, Electric field pulses in close lightning cloud flashes, J. Geophys. Res., 93, 15,933-15,940, 1988.Thomson, E.M., P. Medelius, M.A. Uman, A remote sensor for three components of transient electric fields, IEEE Trans. Ind. Electr., 35, 426-433, 1988a.Thomson, E.M., P.J. Medelius, M. Rubinstein, M.A. Uman, J. Johnson, and J.W. Stone, Horizontal electric fields from lightning return strokes, J. Geophys. Res., 93, No. D3, 2429-2441, 1988b.Thomson, E.M., A theoretical study of electrostatic field wave shapes from lightning leaders, J. Geophys. Res., 90, 8125-8135, 1985.Thomson, E.M., Uman, M.A., Beasley, W.H., Speed and current for lightning stepped leaders near ground as determined from electric field records, J. Geophys., 90, 8136-8142, 1985. Thomson, E.M., Galib, M.A., Uman, M.A., Beasley, W.H., Master, M.J., Some features of stroke occurrence in Florida lightning flashes, J. Geophys. Res., 89, No. D3, 4910-4916, 1984.Thomson, E.M., Characteristics of Port Moresby ground flashes, J. Geophys., Res., 85, 1027-1036, 1980a. Thomson, E.M., The dependence of lightning return stroke characteristics on latitude, J. Geophys. Res., 85, 1050-1056, 1980b.Thomson, E.M., Photoelectric detector for daytime lightning, Electronic Letters, 14, 337-339, 1978. Clegg, R.J., and Thomson, E.M., Some properties of EM radiation from lightning, J. Geophys. Res., 84, 719-724, 1979. Thomson, E.M., Ground currents in Port Moresby lightning, Science in New Guinea,5(2), 67-79, 1977. Thomson, E.M., Daytime photography of lightning, Science in New Guinea,5(2), 79-85, 1977.

 

[David11054]

Arlyn and Fred

I hold no brief for Thompson, nor am I aware of any products he has for sale. His research and articles are totally in agreement with the other articles and books I have read on the subject.I would be interested in any contrary research you could quote. But simple name calling carries little weight, and is certainly impolite. I wish you wouldn't do it.To repeat, I have not read any research that says grounding decreases the chances of being hit.DavidLady Lillie

 

[abe]

I don't know anything about the subject.....

that said.... the great curriculum vitae listed by G May does not automatically classify someone as an honest person. South Korean physician who claimed he cloned a dog with a great cv, was all false and now under arrest. Ten years ago at University of Irvine Medical Center....infertility Argentinan guru fled back to Argentina after unethical practices. Again I do not know Thompson, I read a little about it...but academic greatness does not automatically imply that you will business man with integrity.abe, the unknowledgable

 

[Ross]

I am always amazed

when such talent as is claimed by Dr Thompson goes unacknowledged by his peers. Has any of his voluminous work been subject to peer review? He is obvivously self published but I didn't read any titles published in scientific journals that were subject to peer review.

 

[Gord May]

Peer Reviewed

Read to the bottom of the list for peer reviewed articles*, including those co-authored with Martin A. Uman (who has forgotten more about lightning than all of us will ever know):* IEEE Transactions, Journal of Geophysical. Research, NASA Tech. Briefs, etc.I wish I’d never started offering references, and had just left it to the proponents of “magic bullets” to offer proof of performance from independent third party peer-reviewed sources. Dr. Thomson is not the most eminent authority (tho’ he has some authority), but his “Lightning & Sailboats” has been cited in the academic literature. Notwithstanding, the booklet is not a scientific treatise, but merely a practical tutorial intended for a general audience. Dr Thomson, and I, have the Arizona Courts on our side:“ESE Air Terminals Ruling by US Federal District Court”http://www.lightningsafety.com/nlsi_lhm/ESE_court_case.pdf

 

[Capn Dave]

Oh Boy Gord Ya did it now!!!:{

Merlin is the authorty on lightning, along with earth wind and fire. These are all basic elements. Don't believe me just ask Fred. Because of Fred's theory I went out and bought a couple of trees to plant on my boat. Living in the lightning capitol of the U.S. and being an EE for NASA (retired) We did find grounded objects do hit by lightning more than ungrounded objects. Someone made the discovery a few years back that electricty wants to take the shortest path to complete the curcuit. With a tall grounded object, one would suspect it meets these requirements.Then again I have watched lightning hit shorter masts on boats rather than the tall ones. Also it seems if there are a bunch of grounded masts in close proximity it produces a ground field, when a strike occurs in this field the dammage seems to be far less that when a grounded boat is all by itself.This is just a personal obsveration. Another is we are using the term grounding when we should be using the term bonding. The goal being to spread the current out over a larger area.Fair WindsCap'n Dave

 

[Arlyn Stewart]

Dr. Thomson and his science

A subsequent University of Florida professor offers some clarity; William J. Becker, "Lightning protection systems do not prevent lightning strikes. They may, in fact, increase the possibilities of the boat being struck."I would say that is a significant professional contradiction to Dr. Thomson's assertion that ungrounding boats are hit at equal or greater numbers than grounded.Look, my problem with Thomson is not that he became an expert witness for hire, or that he went into private business selling grounding systems... every expert is free to reap rewards for his hard work and study.My problem is that he took the survey reports of a quantity of struck boats and determined that those which had lightning protection systems had grounded mast and those that didn't had ungrounded mast and that is far from reality and therefore a practice of very bad science. True science does not draw those kinds of conclusions.He then quotes that research as the basis for his theory that an ungrounded mast will be hit as often as a grounded mast and thus there is no advantage of being ungrounded.I'm simply saying, he did not prove that from his surveys as he claims he did, because many if not most of his "ungrounded boats" were very likely grounded. Almost all sailboats with an inboard will have grounded mast regardless if they have a lightning protection system, this via the power train and incidental grounds made by antenna, lighting, and other mast mounted instruments.Moreover, I agree that all inboard boats should have lightning protection systems, but lacking proof that unbonded boats are hit at the same rate as bonded boats, the trailer sailor with an outboard (most outboards do not offer a ground path) may in fact have better survivalbility by staying ungrounded than trying to ground when it is so difficult, if not impossible to do adequately.

 

[Ross]

What percentage of sail boats

suffer lightning strikes each year? I submit that the events are random, rare, totally unpredictable. The presence or absence of "lightning protection" can't be used as a factor in a statistical analysis until a control group of protected boats and a control group of unprotected boats has been exposed to a significant number of equally severe stroms over a multiple year period. I suppose that a marina of a few hundred boats would serve as a valid sample. But how many storms over a period of how many years is needed to show the value of lightning protection.

 

[Bill Roosa]

The IEEE says....

for safety, you need to have some sort of prefered electrical path to ground from an air element to the ground element.Now I'm just an old army officer and not a real bright one at that but is not the IEEE the OFFICIAL standard writting group on things that deal with electricity.I side with Ross, acts of God cannot be prevented but you can reduce your risk. All we are talking about is some connectors and wire.With that all said, I heard that you could short out lightning by grounding your mast to the keel and using a really big metal bottle brush for the air element. Seems that all the little points on the air element (vs one for a standard element) allow positive ions to "leak" into the surrounding atmosphere at greatly reduced voltages and the resulting "positive ion field" shorts out the negative ion field in the cloud base. While a lightning bolt has lots of current it only last for a fraction of a second. The bottle brush is up there all the time "giving off" positive ions so the current would be quite low.Anybody ever heard of this before or have a counter theory?Also, has anybody ever put a volt/amp meter between their air and ground elements. This might be a great way to get a sense of how "charged up" the clouds are around you. Could even be used as a lightning warning system.I'v got my ear muffs on so have at it!

 

[Tom S]

Arlyn does Thomson actually state that ungrounded

masts are struck more often or are you taking his writing and his limited study as him implying that.I have read a lot of what he has written (with the crital eye of an EE and skeptic) and nowhere did I get the feeling the data and the writing suggests that ungrounded masts are struck more often. I felt it was a toss up and for you to possibly suggest that ungrounded masts (or lightly grounded masts through incidental conductivity )are less likely to get hit is no more based in anything other than a guess than anything.The one thing that DID stand out from the study was that boats that had a good solid ground for lightning typically had much less damage to a the boat. So if there is one thing the study did show is that if I was on a boat and lightning did happen to hit I'd rather have a properly grounded mast. Thats a fact that is tough to dispute

 

[Arlyn Stewart]

Thomsons argument

...the likelihood that lightning will strike a boat does not depend on whether the boat is well grounded or not. There is some support for this in the experiences of marine surveyors. Nine marine surveyors in Florida, each of whom had surveyed more than 200 sailboats in their career, reported that between 2% and 67% (on average 34%) of the boats they surveyed for any reason had a lightning protection system. Of the boats that they surveyed because of a lightning strike, they reported that between 0% and 67% (on average 29%) had a protection system. While the individual estimates varied widely between surveyors, there is no support for the argument presented by some sailors that they should not ground their sailboat since it will increase the chances of it being struck by lightning. (Thomson)Tom, you be the judge of what Thomson is saying and whether his application of the data is reasonable... I've read it carefully and find his application unreasonable in the context that it is improper to conclude that a boat without a lightning protection system has either a grounded or ungrounded mast.

 

[Bill Roosa]

Come on Cpt'n Ron

Lets go sailing! The weather has cleared, I've weighed my lightning chain and it looks like a good breeze is a blow'n.I'd invite Tom S. and Ross but I think they are still desirous of hashing out the finer points of Dr. Thomson's paper.

 

[Ross]

I hope this horse is dead

If not, then keep a stick handy.

 

[Old Salt]

chargrined if I the words that I have written

*o

 

[LloydB]

Proposed new study

participants must state if protection system IS or IS NOT installed. Power boats not allowed to participate because lack of 100% response after end of season. Each participant will be required to install golf clubs.

 

[Ross]

Where's that stick?

We can still beat this horse.

 

[Bill Roosa]

Lets form a tiger team

and do some in depth research as to what exactly constitutes a "dead horse". Perhaps we could also write a manual that directs the correct riding of a dead horses. We could also get congress involved. They could edict that the horse is not realy dead and then we could ride it again.My boss actually has a list of about 50 ways to "ride a dead horse". Such is my work environs.

 

[Old Salt]

Ya'll should shred cigarettes and sprinkle tobacco

It was mentioned before and its vaild now. The one that wrote it earlier is just as ignorant as any. No knowledge of technology but talks like an expert. Makes me laugh . Hell if it was 1632 I bet you all would hang Galileo 'cos he said the earth revolved around the sun !!!Blasphemy ! LOLYa'll make me laugh. 'Specially those that don't know nothin' about what an electron is.Keeping believing that anyone with any technical knowledge is talking voodoo and if you can't undertsand it it MUST be wrong. Fools and there followers are easily misled. I see a lot of folks are following the LCD factor (Least common Demoninator).Beware all you seafarers, do not sail west you might fall off the face of the earth.LOL, Fools

 

[Bill Roosa]

Old salt

What is the scientific basis for you suposition? Does the brand of tobacco matter? Should I cover the deck in specific places or just a general "apease the gods" type of coverage. Does menthol work better or worse than regular? How do I keep the tobacco on deck once the storm winds arive? Is there a prescribed time period to get mamimum effectiveness like within 1 hour of a storm or do I just make it a daily event? ;-) Will this interfere with my present grounding system? ;-)These are the things I (and other inquiring minds) need to know if we are going to evaluate your work.