Random Paper of the Day

rk wrote...sniped
Lot of good stuff in this one, a must read.

-- rk

http://klabs.org/history/papers/low_69.pdf

George M. Low
1969

Abstract
The flawless performance of the five manned Apollo flights is
attributed to reliable hardware; thoroughly planned and
executed flight operations; and skilled, superbly trained crews.

Thanks rk - fascinating reading.

This paper talks about how it was that the Apollo program worked so well.
But even so, on the micro level, it involved thousands (tens of thousands)
of people putting in a great effort. Played out in real time to the world,
it took 'get it right the first time' to a new level.

One of the greatest legacies of Apollo is quality control and
organisational methodologies. But was Apollo way ahead of other industrial
efforts, or not. Is it like a mother lifting a car off her child's crushed
hand (a superhuman effort beyond normal expectations) or did we get exactly
what we paid for?

- Peter

rk wrote...

Oops, left off the url:
http://klabs.org/rk/papers/reliability/sandler_72.pdf


Gack! Could you supply a username and password as well please?

- Peter

In article ,
says...
Peter Smith wrote:
[...]
Amazing.

Seconded!


One of the greatest legacies of Apollo is quality control and
organisational methodologies.

Well, *two* of the great legacies, but outside of that, yes, I agree!

The only caution is to understand the scale of a tool. The kind of
organisation methods(*) that was necessary and appropriate for the
~400,000-man Apollo project is massive overkill of a 10-person
engineering team. You don't need a formal CCB (Change Control Board) if
everyone has lunch at the same table.

* If "biology" is the study of life and "chemistry" is the study of
chemicals, the "methodology" is the study of methods, not any particular
method.


Well, coordinating people for large projects was nothing new, using size and
number of people involved as the metric. For instance, take a look at the
construction of the Empire State Building. And they did that with low
technology and without Microshaft Project!

Was it really low-tech by the standards of 1930? The building did have a
Zeppelin mooring mast, after all. State of the Art broadcasting
facilities (including one of the very first FM transmitters). And unlike
the mis-designed World Trade Center, the tallest building in NYC. as of
the 1940s, *did* survive the impact of a big airplane, a B-25 during
World War II.


For organizational (or organisational if you prefer) methodologies, a lot was
taken from the missile programs where they were developing systems management
and even took a lot of the military folks. Ironically, JPL was developing
much of the same, as they learned through their missile programs and early
space shots but was not, from what I understand, the driver for Apollo as the
military folks were. A reference on this is Stephen B. Johnson's _The Secret
of Apollo_.

Around here, we talk a lot about Astronaut Autobiographies, and Chaiken
is considered a book rather than a person. We talk about Jenkin's work
documenting the Shuttle, and Baker's History of Manned Spaceflight. Yet
Johnson's book is *seriously* underdiscussed around here. As but one
example, Johnson does a compare/contrast between two roughly comparable
programs, the basically successful early Mariner flights and the
unsuccessful early Ranger flights.


Nevertheless, I think what was accomplished, in the time that it was
accomplised, was beyond normal expectations. For instance, take a look at the
time from the first unmanned Apollo CSM unmanned flight to the first Apollo
manned flight; and then from that first manned flight to the first lunar
landing.

And the guts needed to send Apollo 8 to the Moon after the failure of
the second Saturn V flight. Compared to today, the balance between risk
and reward was weighted much more toward reward than risk. (Of course,
we suffered with Apollo 1 and Apollo 13...)


Now, one of many good themes in Low's paper was stressing simplicity, in
particular with respect to the interface, [...]

One of my favorite quotes:
…there are two ways of constructing a software design: One way is to
make it so simple that there are obviously no deficiencies and the other
way is to make it so complicated that there are no obvious
deficiencies”. -- C.A.R. Hoare, The 1980 ACM Turing Award Lecture

Almost as good:
The price of reliability is the pursuit of the utmost simplicity. It is
a price which the very rich find most hard to pay. -- Sir Anthony Hoare,
1980.
--
Kevin Willoughby lid

The loss of the American system of checks and balances
is more of a security danger than any terrorist risk.
-- Bruce Schneier

"Kevin Willoughby" wrote in message
...
In article ,
says...
Peter Smith wrote:
[...]
Amazing.

Seconded!


One of the greatest legacies of Apollo is quality control and
organisational methodologies.

Well, *two* of the great legacies, but outside of that, yes, I agree!

The only caution is to understand the scale of a tool. The kind of
organisation methods(*) that was necessary and appropriate for the
~400,000-man Apollo project is massive overkill of a 10-person
engineering team. You don't need a formal CCB (Change Control Board) if
everyone has lunch at the same table.
Yeah, but you still need someone to jot it down and write a memo later

Kevin Willoughby wrote:

Around here, we talk a lot about Astronaut Autobiographies, and Chaiken
is considered a book rather than a person. We talk about Jenkin's work
documenting the Shuttle, and Baker's History of Manned Spaceflight. Yet
Johnson's book is *seriously* underdiscussed around here.

Mostly because it's not very sexy. All too often this group is
sci.space.history.shallow_fanboy.

D.
--
Touch-twice life. Eat. Drink. Laugh.

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

In article ,
(Derek Lyons) wrote:

Kevin Willoughby wrote:

Around here, we talk a lot about Astronaut Autobiographies, and Chaiken
is considered a book rather than a person. We talk about Jenkin's work
documenting the Shuttle, and Baker's History of Manned Spaceflight. Yet
Johnson's book is *seriously* underdiscussed around here.

Mostly because it's not very sexy. All too often this group is
sci.space.history.shallow_fanboy.

D.

I remember the snot I got when I made a question a couple years ago
and I asked for some hard number or other about shuttle flight data;
everyone acted like I was a moron for not knowing who or what
"Jenkins" was. Jesus Christ, but pardon me for preferring the actual
NASA flight data and in-flight anomaly list (e.g., "the Green Book"),
which is what we used as a reference in space station design work . .
.. Sorry, folks, but big coffee table books are fine and all, but
they're called "secondary sources" rather than "Bibles". :-/

--
Herb Schaltegger, B.S., J.D., GPG Key ID: BBF6FC1C
"The loss of the American system of checks and balances is more of a security
danger than any terrorist risk." -- Bruce Schneier
http://dischordia.blogspot.com
http://www.angryherb.net

On Fri, 25 Feb 2005 15:45:05 -0600, Herb Schaltegger wrote:

Sorry, folks, but big coffee table books are fine and all, but
they're called "secondary sources" rather than "Bibles". :-/

Real bibles have math and lotsa numbers

--
Chuck Stewart
"Anime-style catgirls: Threat? Menace? Or just studying algebra?"

On Fri, 25 Feb 2005 21:15:11 GMT, (Derek Lyons)
wrote:

Mostly because it's not very sexy. All too often this group is
sci.space.history.shallow_fanboy.

....Ah-ah-ah, D. Some of us are obviously *not* shallow. Some of us
possess too much girth to be shallow.

OM

--

"No ******* ever won a war by dying for | http://www.io.com/~o_m
his country. He won it by making the other | Sergeant-At-Arms
poor dumb ******* die for his country." | Human O-Ring Society

- General George S. Patton, Jr

In article ,
says...
From what I understand the Twin Towers did survive the strike of the much
bigger airplanes structurally and it was the heat from the fire that brought
them down. I could be wrong.

Basically right, but a couple of notes:

(1) The requirements for the WTC included surviving the impact a big
jetliner. (B-707, iirc, which is very roughly in the same weight class
as the plane that hit the towers.) So the collapse of the towers was a
failure to meet the specifications.

(ii) To the extent that I understand the failure, the structural steel
in the WTC, in and of itself, could not tolerate high heat for an
extended time period. (Back in the days when I would burn down
buildings for a living, the rule of thumb was that if the steel reached
1000 degrees F for 10 minutes, it would soften significantly.) The
structural steel in the WTC was covered with a spray-on foam thermal
insulation. When the planes hit the towers, they disintegrated. The
resulting dust moving at high speed sandblasted the ins ululation from
the steel. The fire then finished the job.


Massive failures are often multipoint failures. Engineers are taught to
build systems with sufficient redundancy to withstand any foreseeable
single-point failure. It's the multipoint failures that are messy. A
couple of on-topic examples: Challenger was brought down by the
combination of cold o-rings and bad management. Apollo 13 was almost
destroyed by a chain of failures, including bad paperwork trails when
the ground-support voltage was doubled, dropping the O2 tank, not
verifying that dropping the tank caused no problems within, an
unorthodox detanking procedure of running the heaters for an extended
period of time, and instrumentation that couldn't correctly report the
actual temperature of the tank. (There may be more, I don't recall.)

Back to the WTC, and getting political for a moment: if the building had
stood until it was evacuated, the loss of life would have been an order
of magnitude less. The USA seems willing to accept that level of loss of
life to terrorist attack without the need to go to war against those who
had neither any involvement in the attack, nor WMD. Thus, the war in
Iraq is the most extraordinary multipoint failure that I'm aware of.
--
Kevin Willoughby lid

The loss of the American system of checks and balances
is more of a security danger than any terrorist risk.
-- Bruce Schneier

On Sat, 26 Feb 2005 14:51:29 -0500, Kevin Willoughby
wrote:

(1) The requirements for the WTC included surviving the impact a big
jetliner. (B-707, iirc, which is very roughly in the same weight class
as the plane that hit the towers.) So the collapse of the towers was a
failure to meet the specifications.

....Guys, there's one other thing that for some reason keeps getting
left out of the WTC collapse discussions. The initial structural
collapse in both cases occurred on one floor. Had this occurred within
the top three floors, we would have not had a collapse. However,
specifically in the case of the first tower to collapse, when that
initial floor collapse happened, it allowed ten *intact* floors to
slam down on the floor underneath the collapsed one. This set up a
cascade effect that saw each descending floor receive the mass of all
the floors above it slamming down on top of it. Based on simulations,
had only the top three floors or less collapsed, the rest of the tower
would still be standing.

OM

--

"No ******* ever won a war by dying for | http://www.io.com/~o_m
his country. He won it by making the other | Sergeant-At-Arms
poor dumb ******* die for his country." | Human O-Ring Society

- General George S. Patton, Jr