Either I'm extremely dense or Scotty's sense of humor is extremely subtle, because it took me 34 years for the penny to drop on this one.
Decker: "Don't worry. She'll launch, on schedule, if we have to tow her out with our bare hands. Right, Scotty?"
Scotty: "Aye. Er, that we will, sir."
"We" is not the subject of the sentence in Decker's line, but only of the dependent clause. So Scotty's not saying, "Yes, she will launch on schedule." He's saying, "Yes, we will have to tow her out with our bare hands."

Maybe it went over my head because I was only 11 at the time...

Decker: "Don't worry. She'll launch, on schedule, if we have to tow her out with our bare hands. Right, Scotty?"
Scotty: "Aye. Er, that we will, sir."
"We" is not the subject of the sentence in Decker's line, but only of the dependent clause. So Scotty's not saying, "Yes, she will launch on schedule." He's saying, "Yes, we will have to tow her out with our bare hands."

Maybe it went over my head because I was only 11 at the time...
