At 01:04 PM 8/10/2005, I sent e-mail to Dr. Richard Gilbrec: (NASA):
Shuttle piggybacking on an external foam insulated
tank is conceptually wrong, since foam always have tendency to peels during lift-off. How I see, it is because during
lift-off tank violently vibrates (jerks). These jerks produce foam shake-off (“bathing birds”) effect. In addition,
small packets of high-low air pressure are created around a tank. As a result, we have tearing off forces applied to the foam.
Every shuttle launch is a Russian roulette enterprise. We are lucky that for many years we were very lucky.
One of the possible (temporary) solutions
to this problem is to apply over foam a high-temperature-resistant external coating. In addition, to smother a lift-off, a
current vehicle stabilization control system must be replaced by a system with significantly shortened reaction time.
On the same day,
I received a reply::
:
Dear Mr. Flikop,
Your suggestion to Dr. Richard
Gilbrech has been received by the NASA Engineering and Safety Center (NESC) system. Thank you for contacting NESC and
for your suggestion on the use of a high-temperature-resistant external coating applied to the foam of the External tank and
your comment to replace the current vehicle stabilization control with one with a shortened reaction time to respond to lift-off
emergencies. We will review your submittal through our NESC review process (Dr. Gilbrech is part of this process) to determine
the appropriate course of action. I will provide the results of the NESC review to you. In the meantime, if you
have any questions, please feel free to contact me.
Thank you!
Peggy Chun
Systems Engineering
Office
NASA Engineering
and Safety Center
At 12:24 PM
8/23/2005, I sent another e-mail::
Dear Peggy,
I want to add some corrections to my message.
To
find a reason why foam is shedding from the external tank, NASA has to consider that tank is a FLEXIBLE body filed with liquid.
During liftoff, tank deforms in all three dimensions. Deformed tank skin cracks foam and loosens it.
Shivering of a tank
skin, tank vibrations, trajectory correction jolts and small packets of high-low air pressure created around a tank produce
a foam shake-off (“bathing birds”) effect.
A highly-tear-resistant and flexible coating applied over the foam
can prevent its shedding.
On 8/25/2005 I received a reply::
Dear Mr. Flikop,
Sorry it has taken me awhile
to respond to you. I have been on travel status this week to a different NASA center. Thank you for the additional
observation. I will add this to your original submittal to enhance the information. Please feel free to contact
me if you have any additional information or questions. I do not have any results of the on-going reviews, yet.
Sincerely,
Peggy Chun
Systems Engineering
Office
NASA Engineering
and Safety Center
On 11/16/2005, I received the following e-mail:
Dear Mr. Flikop:
This is
an update of the status on the review of the suggestion which you submitted to the NASA Engineering and Safety Center (NESC)
regarding coating the External Tank foam and some additional information. The NESC has reviewed your suggestion
through our NESC processes and determined that it should be given to two technical groups set up to establish both the
root cause of the foam problems and to determine and implement a solution.
As a result, the NESC has already forwarded a copy of your suggestion to the technical tiger team (composed
of NASA, industry and academic experts) investigating the External Tank foam debris anomalies and we plan to provide
your recommendation directly to the Shuttle Program for additional review. Due to the overwhelming number of suggestions,
the Shuttle Program will not contact you directly unless your idea is implemented, but should you have any questions regarding
the status, please feel free to continue to contact Ms. Chun or myself.
Answers to email inquiries about
foam loss have been posted by the Shuttle Program at: http://www.nasa.gov/returntoflight/main/email_responses.html.
For further information about
the possible causes of the foam loss and recommendations by the External Tank Tiger Team please see the External Tank Tiger
Team Interim Report at: http://www.nasa.gov/pdf/136219main_FS_ET_Tiger_Team_Report.pdf.
Thank you! We appreciate
your concern, your ideas and your thoughts.
Mark Terrone
NASA Engineering and Safety Center
Systems Engineering Office