In his The Death of the President (1967), William Manchester writes that JFK aide Larry O'Brien said there is "tension on the plane" between LBJ's "people" & JFK's. 

Mrs. Kennedy enters the stateroom where LBJ, his wife, Lady Bird, & Judge Sarah T. Hughes are waiting.  LBJ shakes Jackie's hand & says:
   
"This is the saddest moment in my life".*

Mrs. Hughes will be the 1st woman to administer a Presidential oath.  She has been appointed to the Federal bench in Texas by JFK.  As she is about to begin, someone says:
 
"What about a Bible"?


JFK kept his personal Bible in the nightstand of his private cabin.  It was quickly brought up to the stateroom.  The leather cover bears a gold cross & on the inside are the initials "JFK".

Cecil Stoughton prepares to take "the most important photograph of his life".  It is 2:38 p.m. (CST).

 LBJ officially becomes the 36th President of the United States.  

His first order is brief: "Let 'er roll".*


*from The Death of a President.