Star Wars Episode IV: A New Hope 1977 quotes, page 8

It is a period of civil war. Rebel spaceships, striking from a hidden base, have won their first victory against the evil Galactic Empire.
During the battle, Rebel spies managed to steal secret plans to the Empire's ultimate weapon, the DEATH STAR, an armored space station with enough power to destroy an entire planet.
Pursued by the Empire's sinister agents, Princess Leia races home aboard her starship, custodian of the stolen plans that can save her people and restore freedom to the galaxy....

And now, Your Highness, we will discuss the location of your hidden Rebel base.

This will be a day long remembered. It has seen the end of Kenobi. It will soon see the end of the Rebellion.

General Jan Dodonna

The battle station is heavily shielded, and carries a firepower greater than half the star fleet. Its defenses are designed around a direct large scale assault. A small one-man fighter should be able to penetrate the outer defense.

Pardon me for asking, sir, but what good are snub fighters going to be against that?

Dodonna

Well, the Empire doesn't consider a small one-man fighter to be any threat, or they'd have a tighter defense. An analysis of the plans, provided by Princess Leia, has demonstrated a weakness in the battle station. But the approach will not be easy. You're required to maneuver straight down this trench and skim the surface to this point. [shows the pilots an exhaust port on the computer screen] The target area is only two meters wide. It's a small thermal exhaust port right below the main port. The shaft leads directly to the reactor system. A precise hit will start a chain reaction which should destroy the station. [shows the pilots a demonstration of a torpedo traveling down the shaft and striking the reactor, destroying the station instantly] Only a precise hit will set up a chain reaction. The shaft is ray-shielded, so you'll have to use proton torpedoes.

Wedge Antilles

That's impossible, even for a computer!

Luke

It's not impossible; I used to bullseye Womp rats with my T-16 back home. They're not much bigger than two meters.

Dodonna

Then man your ships, and may the Force be with you.