Feasibility study of a stand-off gap switch in exploding bridgewire initiator
 

The following report was written by my Daddy...He is a real student of the quantitative...If one were to compare his writing to mine, one would find that the only difference is that I quantise the subjective.



Accession Number : AD0602920

Title :

Descriptive Note : Summary rept.

Corporate Author : AEROJET-GENERAL CORP DOWNEY CA

Personal Author(s) : Bryla, Theodore N.

Handle / proxy Url : http://handle.dtic.mil/100.2/AD602920 Check NTIS Availability...

Report Date : 18 DEC 1962

Pagination or Media Count : 83

Abstract : The investigations were conducted to establish the feasibility of incorporating a high voltage switch within the electrical header of an exploding bridgewire initiator and to determine the electrical capabilities of the voltage switch to meet missile safety and functional requirements. Two types of high voltage switches were designed, developed, and fabricated within the electrical header of an EBW initiator. The electrical capabilities of these voltage switches were evaluated under various environmental conditions. Their conformance to the required design parameters established the feasibility of including a high voltage switch within the electrical header. Various stand-off gap switch (SOGS) and stand-off voltage switch (SOVS) engineering models were studied in the feasibility investigation. Fifty prototype SOVS initiator headers of the final design configuration were fabricated. These units, designed for a coaxial input, utilize the electrical voltage breakdown characteristics of an aluminum-oxide coating for the voltage switch.

Living proof that the apple doen't fall too far from the tree... You may want to consider writing your more intellectual pieces in crayon though.... so that the less edjumatated among us can have a chance at knowledge also....;) Sometimes, even I have to resort to Webster to help in the deciphering lol

EBWs are buggy whips.

Why? It is obvious to anyone actually paying attention:

1. Uncertainty of the actual DDT phenomena in the IP (bow wave or hot spots?)
2. The extreme sensitivity of initiation threshold to IP explosive specific surface area and density
3. Timing effects of the BW location, residual stress and morphology
4. Poor pressure output at the initial pressing necessitates the use of further boosters

Slappers are the way to go. Way better safety with the increased dI/dt requirements. No DDT issues due to the prompt initiation of a high density pressing after the flier smacks it. Further increased safety by separating the explosive from the electrical circuit.

Of course, there are always lasers...

Er...um...yeah.

I thought it was about quick release explosive charged umbilical connections for missiles in the silos...not some cowboys and buggies with lasers on their heads.

by slappers due you mean TBI, through bulkhead initiators?

you still need a device to initiiate a shockwave and EBW's are useful there.

but I don't know why he was investigating putting the switch in the EBW

Didja check the date on that feasibility study? It was done before most of you Boyz were even a glimmer in your Dadys eye....

I did see the date. That is a pretty early application of the concept for improving safety and other stuff.

Compared to what came before, EBWs are a huge improvement. As a materials person I find them interestingly complex. We'll probably stop using them long before we fully understand all of the phenomena involved.

(sitting a few hundred yards from where EBWs were likely invented)

actually, I was doing my first rocket experiments as a kid in 62, but did not use EBW's until mid 80's and I consider them the only item to use for setting off explosives.


but can anyone answer why they would want to put the switch internal to the EBW?

Reduce dwell time and possible interference.

Tabs. I don't want to cast doubt on your paternal lineage, but the punctuation and spelling in the above missive is certainly enough to arouse suspicion.

The point is to show the analytical mind...

If it wasn't quantifiable it didn't exist for him...he was a "Scientist"