"since the airline had started flying jets five years earlier." -> "since their introduction by the airline five years earlier"? Or similar? Just trying to avoid the quick repeat of "jet".
Changed to "It was the first fatal accident on a Pan Am jet aircraft since the company had taken its first delivery of the type five years earlier." It still reads wonky but other wordings imply that Pan Am was the company that had first flown jet aircraft. It didn't.
"The exact way that the ..." reads strangely to me, but I guess it's a pref/ENGVAR thing, I would see it as "The precise way in which the..."
I've been staring at that one for a while and think it might be an ENGVAR thing. I could reword it as "the precise mechanism of the ignition of the fumes..." etc., but that comes over as overly pretentious to me.
Aircraft name is in italics in the infobox and in plain text (but quotes) in the main part of the article.
Done
"in San Juan, Puerto Rico to" comma after Puerto Rico.
Done
"The flight left San Juan at... " reiterate, "Flight 214 left ..." because previous sentence talks about a different flight.
Done
"got off the plane in Baltimore" -> "disembarked in Baltimore".
Done
You've used a comma separator in other articles for altitudes in feet, that worked for me.
Done
"on fire.[5][1](pp1,3) " order, and a space between , and 3.
Done. I wasn't aware the {{rp}} template allowed me to put a space in there.