Space Forum / Shuttle / October 2007

On his Challenger website, Jon Berndt writes as follows:

"Both the right and left hand rock and tilt actuator positions were
known up until just prior to the disintegration of the 51-L stack
(Footnote 20)."

Jon's 'Footnote 20' is this link:

http://history.nasa.gov/rogersrep/v3n44.htm

Jon then refers to these plots as his "Figure 9:"

"According to the telemetry (as shown in the plots in Figure 9) both
SRBs had their nozzles canted so as to thrust slightly inward and
towards arresting a positive roll rate (see next paragraph), when they
were 'liberated' from the ET."

However (as you can better see in the NASA link provided above), the
data in Jon's "Figure 9" ends at t+70 seconds, well before any
"liberation." So what Jon states is not "shown" at all.

This is akin to the troubled history of JSC's Arnie Aldrich and Tom
Moser on the same subject, as inconsistently given in closed-session
testimony (but not beginning until February 7, 1986, more than ten
days after the Challenger catastrophe).

(Forum chatter has it that Jon Berndt now writes for the Houston
Chapter of the AIAA.)

JTM -- www.mission51l.com