Edwards air show B-1 speed record attempt

"Gene Nygaard" wrote in message
...
On Fri, 24 Oct 2003 16:55:34 -0700, "Tarver Engineering"
wrote:


"John R Weiss" wrote in message
news:_Bimb.21153$HS4.74853@attbi_s01...
"Tarver Engineering" wrote...

And you start with pounds as the basis and convert to have the fuel
vended,
no matter what units of volume are used. Then the weight of the
airplane is
checked to see if the fuel got onboard.

So, the FE begins with a takeoff weight, calculates the fuel to be
ordered
and leaves the weight on the dash for the pilot to cross check.

Nope! It is apparent you don't know at all what you are talking about.

In "a high reliability sysetm" such as that in a 777 or 747-400, the
fuel
vendor
is simply told the "final fuel" figure in kilograms

My goodness Weiss, you mean what I wrote in the first place is completely
correct. At least my explanation of the process leaves the glider 767
safety report as a possibility.

You must be forgetting the first problem with the Gimli
glider--inoperative onboard fuel gauges.

Nygaard, if they had bought the fuel by weight, there could have been
confusion about liters.

On Fri, 24 Oct 2003 17:14:36 -0700, "Tarver Engineering"
wrote:


"Gene Nygaard" wrote in message
.. .
On Fri, 24 Oct 2003 09:12:12 -0700, "Tarver Engineering"
wrote:


"Gene Nygaard" wrote in message
.. .
On Fri, 24 Oct 2003 08:15:17 -0700, "Tarver Engineering"
wrote:


"Gene Nygaard" wrote in message
.. .
On Thu, 23 Oct 2003 12:46:36 -0700, "Tarver Engineering"
wrote:

snip
Why not "pounds", like an aircraft?

Because there are too many engineers too stupid to understand the
simple fact that those pounds are, by definition, units of mass
exactly equal to 0.45359237 kg.

I find it unlikely that there are many engineers that can not operate
a
calculator.

Show me a calculator that will figure out *which* pounds are being
used, so that they get converted correctly.

Aircraft already have units of measure. Why use different units? Why is
anyone working in NASA Operations that does not know aircraft units?

What you write is a non-sequitur.

You also underestimate the effects of systematic miseducation. The
mere existence of a conversion factor from pounds to kilograms on a
calculator isn't going to undo the fact that some favorite teacher has
drummed into someone's head the notion that pounds are always units of
force and not units of mass, so you can't really convert between
pounds and kilograms. In fact, in today's screwed up world, there are
a number of textbooks which tell you just exactly that.

Why change from the units of aerospace to some other arbitrary set of
units
in the first palce?

Because it is the interdisciplinary and International System of Units.
There is no reason to have to learn different units of measure for
each activity we engage in.

When we engage in industry, we must use the language of that industry, as
well as the existing infrastructure. A big part of training to do
engineering is to apply a reference and measurement system applicable to the
problem. Aerospace is expressed in feet, pounds, clockwise and attempts to
use alternative SI units have resulted in problems.

Such changes have taken place in the past, of course. But when the
air speed indicators of many aircraft were changed in the second half
of the twentieth century, they weren' t changed to metric. Instead,
they were just changed from one Fred Flintstone unit to another.

How is the arbitrarily selected "metric system" inherently better than
another "system of measurement"?

You complained about arbitrary change. So why is it only "arbitrary"
in your definition if it is to the metric system, and not arbitrary if
it is from one Fred Flintstone unit to another?

That's about as silly as if the United States were to change now from
inches of mercury to millimeters of mercury for altimeter settings.

millibars.

No, that's not what I said, and not what I meant.

In my 20 20 hindsight I can say for a fact that
attempting to apply si units to aerospace has come at the cost of
confusion
and we are very fortunate to have avoided toumbstones.

In fact, the calculator is the end of any need to change to si
units, as si is a slide rule reality.

Any time you make a conversion, at least other than by factors that
are exact powers of 10, you lose something.

Perhaps, but not enough to matter from an engineering, of operational
standpoint.

Certainly enough to matter.

Such added "signifigant digits" of accuracy are a false advantage.

What "added 'significant digits'" are you talking about?

Did you understand this next part at all?

Often the "something" which you lose is the sense of how precise a
measurement is.

It isn't just a "false advantage"--like I said, you've lost something,
even if you have a appropriate number of significant digits, and even
more so if you have too many of them. Or, if you add an explicit
"plus or minus" to replace what was implicit in the original
measurements, you've lost readibility and conciseness of expression.

What we lost is a spacecraft, to prople being silly about political
correctness.

We lost a spacecraft because the vendor didn't follow the specs, and
because of sloppiness and indecisiveness on the part of NASA.

Go read the NASA Inspector General's followup report, NASA Use of
Metric Assessment, on this at
http://www.hq.nasa.gov/office/oig/hq...s/g-00-021.pdf

[from the cover letter there]
Following the loss of the Mars Climate Orbiter, the NASA Office of
Inspector General initiated a review of the Agency’s use of the metric
system. By law and policy, the metric system is the preferred system
of measurement within NASA. However, our review found that use of the
metric system is inconsistent across the Agency. A waiver system,
which was required by law and put into effect to track metric usage
and encourage conversion, is no longer in use. In addition, NASA
employees are given little guidance on the Agency’s policy and
procedures regarding use of the metric system.

Based on our review, we made eight recommendations intended to improve
the use of the metric system within NASA in accordance with national
policy and NASA guidance. We recommended NASA:

• reexamine the Agency’s effort to convert to the metric system and
develop a new approach for converting to the metric system,
• closely monitor technical interfaces between metric and English
units,
• reinvigorate the metric waiver system, and
• use the metric system as the preferred system for interactions with
the public


Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/

"Tarver Engineering" wrote...

That's about as silly as if the United States were to change now from
inches of mercury to millimeters of mercury for altimeter settings.

millibars.

Hectopascals.

"Tarver Engineering" wrote...

Nygaard, if they had bought the fuel by weight, there could have been
confusion about liters.

But, as you pointed out, industry has to adapt to the infrastructure. The
infrastructure has been dispensing fuel in gallons or liters for years. The
ability to "[buy] the fuel by weight" does not exist in commercial aviation.

"Tarver Engineering" wrote:


"phil hunt" wrote in message
...
On Thu, 23 Oct 2003 12:46:36 -0700, Tarver Engineering
wrote:

Which gallon US or Imperial ?

Either would do; in my figures below i was using Imperial gallons
(because I know how big they are).

Why not "pounds", like an aircraft?

Pounds aren't as unit of volume.

Immagine that.

True of course...but aircraft fuel is indeed measured in pounds
because you need to know how much weight you have.
--

-Gord.

"John R Weiss" wrote in message
news:BMjmb.20410$e01.40419@attbi_s02...
"Tarver Engineering" wrote...

Nygaard, if they had bought the fuel by weight, there could have been
confusion about liters.

But, as you pointed out, industry has to adapt to the infrastructure. The
infrastructure has been dispensing fuel in gallons or liters for years.
The
ability to "[buy] the fuel by weight" does not exist in commercial
aviation.

All fuel is bought as weight, that is how an aircraft works. The fact that
you pay for volume is a book keeper's issue.

"John R Weiss" wrote in message
news:BMjmb.20187$Tr4.43241@attbi_s03...
"Tarver Engineering" wrote...

That's about as silly as if the United States were to change now from
inches of mercury to millimeters of mercury for altimeter settings.

millibars.

Hectopascals.

I never saw an hectopascal baro-correction.

"Gord Beaman" wrote in message
...
"Tarver Engineering" wrote:


"phil hunt" wrote in message
...
On Thu, 23 Oct 2003 12:46:36 -0700, Tarver Engineering

wrote:

Which gallon US or Imperial ?

Either would do; in my figures below i was using Imperial gallons
(because I know how big they are).

Why not "pounds", like an aircraft?

Pounds aren't as unit of volume.

Immagine that.

True of course...but aircraft fuel is indeed measured in pounds
because you need to know how much weight you have.

And you burn some pounds per hour, at some SAT.

"Tarver Engineering" wrote...

millibars.

Hectopascals.

I never saw an hectopascal baro-correction.

So, that doesn't make it any less an international standard for altimeter
settings.

On Fri, 24 Oct 2003 09:42:09 -0700, Tarver Engineering wrote:

Why not just admit that SI is just another arbitrarily bounded measurement
system and get over the eurocentic ego trip?

Of course SI is arbitrary -- all measurement systems are. Though it
isn't Eurocentric, particularly, since a third of its fundamental
base units were invented outside Europe.

--
"It's easier to find people online who openly support the KKK than
people who openly support the RIAA" -- comment on Wikipedia
(Email: , but first subtract 275 and reverse
the last two letters).