© 1999 - 2018 Standard Heater Tube, LLC

234 W. Bandera Rd. #350

Boerne, TX 78006


Phone: 830-755-8695

Fax: 830-755-8697

Email: davidm@standardheatertube.com

Mr. Heater Tube Sez

Mr. Heater Tube Sez he has wondered, in a quizically amazed way, about the recent antics of ASTM Subcommittee J, as they proceed to falsify specifications for heater tubes in D3241. Mr. Tube Sez we should all be able to read and to use clear technical specifications; that we don't need muddled, undefined, requirements.


Mr. Tube affirms the reality that a tube requirement can hardly be undefined and constrained by specification all at one and the same time. It's a heater tube oxymoron!

King Tube remarks that he's talking about the recent insertion of general comments masquerading as "specs," requiring "Rotational cut buffing technique with polishing compound to achieve mechanical surface finish."


The King of Heater Tubes states that since we already have clear, objective, numerical mechanical surface finish specs (which we fully meet), what purpose is served by adding to D3241 this irrational gibberish that nobody understands?

Mr. Heater Tube's Google search for "rotational cut buffing" produced an amazing array of techniques for rotary buffing car parts. Mr. Tube thought, "What the Hey???" King Tube knows his own rotational process is patented and published, while nobody knows what other's do. Mr. Tube sees their resulting scratched finish and understands they produce an inferior product. Mr. Heater Tube Sees and Sez that they confuse a "scratchy tube" with a "polished" one.  Sad!!!

The Master Crafter of Heater Tubes Sez he has carefully reviewed all manner of un-named polishing compounds, from blasting sand to the finest talc. Then, he Sez from the Specification there is no way to know which one(s) produce a mechanical surface finish ASTM finds desirable, or who to ask, or how they would know, or why they even care. King Sez his tubes already fully meet all specs for mechanical surface finish. He Sez this was documented by the Energy Institute Report back in 2006. Mr. Tube just Sez, "Wow!!!"

Then, Mr. Heater Tube uses logic to reason that since the specification presents no definition or description of an acceptable polishing compound at all, then it must actually be unimportant. In turn, that fact is evidence of dishonesty; adding something unnecessary and undefined and meaningless to the specification. And, if the specs are dishonest, why bother with them? Mr. Tube Sez we'd all be better off without dishonesty and without a false tube specification.

Mr. Heater Tube Sez he understands how users of D3241 are bewildered by falsified specs: falsified by overlaying undefined terms onto hard numerical specs. The resulting    meaningless and irrelevant requirements are right there for everybody to see! Asked whether competing techniques of a competitor meet the new specification, King Tube Sez, "I've got no real idea what those imposters are doing! Or, what  ASTM is thinking!"


He adds, "We still make the finest tube on the planet. We can also now accommodate an inferior tube with a scratched finish for those who prefer it, so just give us a call either way."


Mr. Heater Tube occasionally casts his eye across the pond and sees some rather silly goings-on.

Mr. Heater Tube recently heard from someone there who insisted that our product, which is created and used extensively in ASTM D-3241 testing for thermal stability of aviation (jet) fuel, is "unsuitable." This is so, they say, because Def Stan 91-91 prohibits it's use (claims it "shall not be used"). The King of Heater Tubes is delighted to proclaim the contrary as an obvious reality and the truth.

Mr. Heater Tube recognizes Def Stan 91-91 as an aviation fuel specification of the British Ministry of Defense (MOD). Mr. Tube clarifies that since we do not manufacture, sell, test, or use aviation fuel in our business, it is  a puzzle how anyone would try to apply Def Stan 91-91 at all. He further Sez that, clearly, anything associated with the purchase or sale of jet fuel, or it's use, is outside the scope of our business interest. He Sez, as a conclusion, that our interest lies in making high quality heater tubes for D3241 testing, and that is our sole business activity.

The King declares that since Def Stan91-91 is a fuel specification, it isn’t, and cannot be, a tube specification. He Sez tube properties are actually enumerated in ASTM D3241, which is contained within, but is separate from, Def Stan 91-91 fuel specification.

Mr. Heater Tube notices that ASTM D3241, as implied by its name, is authorized by and is property of ASTM International, an international standards organization, while Def Stan 91-91 is property of and authorized by the British Ministry of Defense. The fuel specification used across the pond no more extends to specifying heater tube properties than does a specification for, say, English tea. The King proclaims that Def Stan 91-91 is not directly applicable to, and is actually irrelevant to, specifications for our product tube.

Mr. Heater Tube Sez he has read the truth in the Foreword to Def Stan 91-91 that, "This standard has been developed solely for the use of the MOD and its contractors in the execution of contracts for the MOD." Mr. Tube just Sez this sentence is important. It clearly and directly limits the scope and purpose of the document. It's only about, specifically, affairs of the British MOD. Mr. Tube sees and Sez that the deliberate location of this limitation (through the document Foreword) indicates and establishes it as primacy to, priority over, and supremacy over other inferior comments --- such as a minor and contrary note buried deep in the document.

The King of Heater Tubes has faithfully considered the urgent plea that is carefully hidden deep within that note, a plea offered to the effect that product of some manufacturers "shall not be used." The actual full note does say: "Thermal Stability is a critical aviation fuel test and while competition among equipment manufacturers is to be encouraged, aircraft safety must remain paramount. It is known that there are heater tubes being supplied by sources other than the original equipment manufacturer (OEM). Until the alternative manufacturer's tubes have been demonstrated to be equivalent to the OEM's test pieces, to the satisfaction of the AFC, they shall not be used. A list of manufacturers whose heater tubes have been found to be technically suitable is as follows: a) PAC - Alcor b) Falex." This note is famously, pompously, British.

Mr. Heater Tube sees and Sez how this note brings up something else exclusively British that is called the AFC or "Aviation Fuels Committee" and he Sez how this note speaks to "the satisfaction of the AFC." Mr. Heater Tube has no problem pointing out that the "satisfaction of the AFC" isn't a tube property at all, and isn't specified or defined within D3241 (the official document that establishes tube specifications, which is already referenced within Def Stan 91-91). Mr. Tube Sez this silly criterion simply cannot even be applied at all because the "satisfaction of the AFC" isn't a measurable or quantifiable tube property of any kind. The King of Tubes Sez It seems to be more of a statement about a political preference or agenda of some unidentified kind and purpose, and the King of Tubes is simply uninterested in anyone's political preferences. Also in this regard, Mr. Heater Tube chimes in that our product originates solely with us. He Sez it is ours and belongs to us (until sold, by us), and it is manufactured by us. Accordingly and per accepted word usage and meaning, Mr. Heater Tube is certain that we are the Original Equipment Manufacturer (OEM) of our own product. The King of Heater Tubes proclaims the notion absurd that an outside entity is, or may be, exclusively or even actually our OEM (or anyone else's OEM). The King of Heater Tubes would never permit or allow our inert product to be any threat of any kind to aircraft safety, as evidenced through worldwide usage for nearly two decades. Mr. Heater Tube Sez it is past time that the AFC wake up to reality and smell the American-made coffee.

Mr. Heater Tube Sez that heater tube properties are carefully and completely enumerated and clearly specified within D3241 itself. He Sez our product meets every specification and there is no dispute about this fact. Def Stan 91-91 cannot factually alter that in any way. Mr. Heater Tube affirms that it also isn't possible for Def Stan 91-91 to both follow, and simultaneously alter or even ignore, the specifications in D3241. That is a critical  problem with Def Stan 91-91. Mr. Heater Tube Sez it must be so.

Mr. Heater Tube takes note that Def Stan 91-91, a jet fuel specification, also embodies dozens of other important physical and chemical tests in addition to the specification for high-altitude thermal stability of fuel as measured by ASTM D3241. Mr. Tube affirms that D3241 only attempts to set forth and establish heater tube properties (the supplier of an inert testing coupon is not a tube specification, so it also isn't and cannot be a "critical material property"). By incorporating D3241 as a fuel spec, British MOD has already given its tacit assertion and agreement to use the official set of heater tube criteria that are incorporated therein. The insertion of contrary language within Def Stan 91-91 creates, itself, a conflicted and duplicitous double message. Def Stan 91-91 users are simultaneously mandated to strictly follow the procedures and practices (and tube specifications) outlined in D3241, and then, also, to capriciously alter the formal, official heater tube requirements of D3241. Mr. Heater Tube Sez that is, literally, nonsense.

Mr. Heater Tube claims it is self-evident that neither the British MOD, or ASTM ,or any other standard-setting agency, has authority to establish criteria for who may manufacture tubes. Their job would seem to involve developing and writing fuel specifications and even the technical tube requirements, and then to encourage users to voluntarily apply the test in the agreed manner. As they themselves say,  the fuel specification and entire document itself "has been devised solely for the use of the MOD and its contractors in the execution of contracts for the MOD."

The King of Heater Tubes happily proclaims that there are far-reaching consequences to the MOD's mandated limitation that the entire document "has been devised solely for the use of the MOD and its contractors in the execution of contracts for the MOD." The King announces that, accordingly, if you are not an MOD contractor, you can freely use our product. If you are not involved in executing MOD contracts, you are free to select us as the supplier. And, if you are doing business involving other than the British Ministry of Defense, your business activity is outside the parameters of Def Stan 91-91, which simply doesn't apply.  Because of this clear limitation to the use or applicability of Def Stan 91-91, we make it our practice to not intentionally sell our product to the British MOD or any of its contractors who may be involved in the execution of MOD contracts. If you are not among that exclusive group, we welcome the opportunity to talk to you about your heater tube requirement. It is a clear fact that the document has nothing at all to do with private transactions; ones used throughout the world but not involving the MOD. Factually in this case, Def Stan 91-91 is irrelevant. Def Stan 91-91 is a true fuel spec, not a tube spec.

As policy, we do not contend against or argue with people seemingly determined to mis-interpret and mis-apply Def Stan 91-91.        


Mr. Heater Tube Sez you cannot resolve a political problem by proposing a technical solution. He Sez political problems need political solutions.

To people who ask why his company has had trouble obtaining an ASTM supplier listing, Mr. Heater Tube Sez it is politics.

Mr. Tube points to factual evidence: Per official, written, ASTM guidelines, all a listing requires is equivalence and product availability,  Mr. Heater Tube sez these are both in evidence via this website, and that one political problem is that ASTM won't follow it's own guidelines.

Mr Heater Tube also wonders why ASTM tries to endorse and certify another supplier, which is contrary to their own clear words in D3241 that listed suppliers aren't endorsed or certified.

Mr. Heater Tube also wonders at efforts to "approve" and "sanction" the former monopoly supplier by incorrectly naming them as "original" equipment manufacturers. Mr. Tube Sez, "What about us? We're as original as can be!"

The King of Heater Tubes proclaims it is clearly wrong for ASTM to favor the former monopoly supplier in any way, when they could just as easily comply with their own Antitrust policy. The King Sez Antitrust law prohibits unreasonable restraint of trade and promotes open competition but ASTM avoids competition altogether and with a large toe on the scale.

King Tube Sez 19 years of restraining trade is profoundly unreasonable on its face.


Mr. Heater Tube has discovered that Statistics can't ever prove equivalence. He Sez there's three plenty good scientific reasons as to why:

The King of Heater Tubes proclaims (as shown elsewhere here), that (1) Equivalence is a scientific fact. There's no question to be answered. It is silliness to think that statistics can prove or disprove an essential fact.

The Master Crafter of Heater Tubes Sez it's factual that chemical and mechanical  equivalence is an inherent quality built in to every particular alloy produced by an aluminum mill -- of which there are dozens. He knows, and Sez, that 6061-T6 heater tube alloy, aka aircraft aluminum, has all of its properties permanently, irreversibly, and quite deliberately fixed from the get-go; there is nothing a tube supplier can do to change these basic chemical or mechanical properties or, consequently, equivalence, after that alloy batch is produced. Certainly rubbing a tube with abrasive goo changes no properties at all. Mr. Tube considers this self-evident.

Mr. Heater Tube also Sez that since a practical working definition of equivalence doesn't exist, (2A) there's no statistical criterion to apply, and nothing for a statistical evaluation to confirm. He also Sez that (2C) statistics can't prove something that's undefined or non-existent in the first place


The Heater Tube Proud Provider proclaims it's also not possible for Equivalence to be proven statistically (3) because of Reaction Kinetics. Mr. Heater Tube Sez it is evident from freshman Chemistry that reaction rates generally double for each 10 degree C increase in temperature, and this rule applies to rates for fuel deterioration reactions. So, he Sez, Equivalence would mean generally equal reaction rates. Yet, Mr. Heater Tube Sez that the standard for  equivalence is often expressed as equal breakpoint plus or minus five degrees. Any tubes which vary by a halving or doubling of reaction rate simply cannot be called equivalent --- so it doesn't matter whether statistical trickery indicates so, or not.

Mr. Heater Tube agrees with what Mark Twain Sez: that there are three kinds of lies; lies, damned lies, and statistics.