IMNSHO I must disagree.

It is the political influences that cause most of the poor management within
NASA.  Granted, you have some senators that are wanting to look good by sticking
their fingers into the NASA business but the NASA higher management is doing the
same in return in order to get more money and power to do its thing.
The internal workings (?) of NASA are so infected with political intrigue that
most decisions are not based on engineering expertise but on political concerns.
This politics starts at the top with the interface with the politicians and goes
down to the lowest rank and file employee trying to keep his/her job by
satisifying his/her boss's petty concerns about how something will look in a
briefing or a report.







barry_ma%[email protected] on 03/30/2000 07:59:59 PM

Please respond to barry_ma%[email protected]

To:   emc-pstc%[email protected]
cc:    (bcc: Oscar Overton/Lex/Lexmark)
Subject:  RE: Mars Lander EMC problem?




Lou,

IMHO, the "poor management" problem does not only belong to NASA, also to the
senate committee. The committee should help NASA improve their Verification and
Qualification procedure.

Not long ago NASA had a failed mission due to a design mistake omitting
transition unit for propelling force in Pound to Kilogram. Pretty soon they had
the second failed mission. This time it is because "The software ... was not
properly implemented" (see the NASA report below).

Are all these overlook mistakes are forgivable to taxpayers?

Barry Ma
[email protected]
---------- Original Text ----------

From: "Lou Gnecco" <[email protected]>, on 3/30/00 2:20 PM:


Sen. McCain is on the committee that oversees NASA. He recently said that the
basic problem is poor management. IMHOP he's right.
lou

--------------

Scott Lacey

Below is an excerpt from the complete NASA report.

<<Premature shutdown of descent engines.
PLAUSIBLE. A magnetic sensor is provided in each of the three landing legs to
sense touchdown when the lander contacts the surface, initiating the shutdown of
the descent engines. Data from MPL engineering development unit deployment
tests, MPL flight unit deployment tests, and Mars 2001 deployment tests showed
that a spurious touchdown indication occurs in the Hall Effect touchdown sensor
during landing leg deployment (while the lander is connected to the parachute).
The software logic accepts this transient signal as a valid touchdown event if
it persists for two consecutive readings of the sensor. The tests showed that
most of the transient signals at leg deployment are indeed long enough to be
accepted as valid events, therefore, it is almost a certainty that at least one
of the three would have generated a spurious touchdown indication that the
software accepted as valid.  The software - intended to ignore touchdown
indications prior to the enabling of the touchdown sensi!
!
ng logic - was not properly implemented, and the spurious touchdown indication
was retained. The touchdown sensing logic is enabled at 40 meters altitude, and
the software would have issued a descent engine thrust termination at this time
in response to a (spurious) touchdown indication.
MOST PROBABLE CAUSE OF LOSS OF MISSION>>


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