Did Obi-Wan Kenobi know how to destroy the Death Star without the help of the stolen plans?

Question

At the end of Star Wars: A New Hope, the Rebel Alliance, with the help of the stolen plans of the Death Star and an accurate proton torpedo shot from Luke Skywalker's X-wing guided by the Force, destroyed the Death Star, but, throughout the film up to that point the figure of Obi-Wan Kenobi was always present and played a vital role regarding the fate of the gargantuan battle station.

Throughout a sequence of events in the film, Obi-Wan Kenobi's words and actions demonstrated that he not only knew of the galactic import of the Death Star but also how the battle station worked.

First, the old hermit felt its power during the destruction of Alderaan.

I felt a great disturbance in the Force as if millions of voices suddenly cried out in terror and were suddenly silenced. I fear something terrible has happened.

Then, on board the Millennium Falcon, while following a lone TIE/LN starfighter, Kenobi, from a good distance, detected the space station.

INTERIOR: MILLENNIUM FALCON -- COCKPIT.
The distant star can be distinguished as a small moon or planet.

LUKE: Look at him. He's headed for that small moon.

HAN: I think I can get him before he gets there...he's almost in range.

The small moon begins to take on the appearance of a monstrous spherical battle station.

BEN: That's no moon! It's a space station.

Obi-Wan said that neither fighting or surrender were viable choices, but a third option was available to them. The old Jedi was able to navigate his way through the station and deactivate the Death Star’s tractor beam generator.

We have to break the tractor at its power source in order to execute a clean escape, Luke. The tractor beam is coupled to the main reactors at seven locations.

At the climax of the movie, using his newfound abilities, Obi-Wan Kenobi was able to guide Skywalker during the Battle of Yavin so that he could successfully destroy the Death Star with proton torpedoes.

It is not unreasonable to think that Obi-Wan could have discovered potential weaknesses in the battle station that he could have exploited in order to destroy the Death Star, but, he never did because his priority was to save Princess Leia and his new friends and honor a old one (Leia's father)'s request which led him to confront Darth Vader with his further heroic death.

In view of the foregoing, I ask whether there are sources (canon or Legends) that detail the idea that Obi-Wan Kenobi knew how to destroy the Death Star without the use of the stolen technical schematics of the Empire's planet-destroying Death Star.

Answer 1

No

There's no real proof that Kenobi knew anything about the Death Star, only that he was able to quickly piece together disparate bits of information into a coherent picture. This speaks more to his experience, wisdom, and talents as a Jedi.

I felt a great disturbance in the Force as if millions of voices suddenly cried out in terror and were suddenly silenced. I fear something terrible has happened.

Through the force, Kenobi felt the sudden deaths of billions of people as Alderaan was destroyed. That required no knowledge of who, what, or why it had happened, only the consequences. Being the experienced Jedi and general that he was, he could probably make a few educated guesses as to who had done it, and even where those lives had been lost.

That's no moon! It's a space station.

I suspect one of the novelisations would clarify this, but Kenobi was, using his wisdom and experience, able to make a guess that the Empire would have built something capable of destroying a planet, and that it would have to be pretty big.

He'd already felt countless lives to be lost through the force, then to find that Alderaan had been destroyed. He shows that he's already made this connection earlier in the same scene.

Han Solo : Our position's correct, except... no Alderaan.
Luke Skywalker : What do you mean? Where is it?
Han Solo : That's what I'm trying to tell you, kid; it ain't there... It's been totally blown away.
Luke Skywalker : What? How?
Obi-Wan Kenobi : Destroyed, by the Empire.

As for knowing how to deactivate the tractor beam so they could escape, he knew that because they found the information in the Death Star's own computers. His experience during the Clone Wars would have given him plenty of insights into how such systems worked and since there's no indication that the Death Star's tractor beams were any different to those that had been in use during his service, there's no reason why he wouldn't be familiar with them.

As for the absolute core of your question, "Would he have known the Death Star's fatal weakness?"

Why would he. Kenobi's connection to the force and military experience gave him enough insight into the situation to help get the Falcon away again, but, as Rogue One shows, that specific flaw in the Death Star was deliberately put there in secret by Galen Erso.

It had come to the attention of the Rebel Alliance because of the efforts of Jyn and Cassian, but there's no way that Kenobi would have known that. He could have guessed that was specifically the vital information that R2 was carrying, since a planet-destroying battle station is a fairly big threat to freedom in the galaxy and knowing how to destroy it would be vital information. After all, there's no such thing as coincidence. But there's no suggestion in the film that Kenobi attempted to access that data.

Answer 2

Let's back up and consider some parts of the story that don't line up very neatly

Obi-wan didn't know what the Death Star was until he sensed it through the Force

Alderaan has been wiped out. Obi-Wan wouldn't have any reason to hide knowledge of the Death Star from anyone on the Millennium Falcon. Then we have this scene

LUKE: [The TIE fighter that just attacked us] followed us!
BEN: No. It's a short range fighter.
HAN: There aren't any bases around here. Where did it come from?
(snip)
LUKE: Look at him. He's headed for that small moon.

Up until this point Ben has only been skeptical of chasing the fighter. If he really knew what it was, he would have said something instantly. Remember, they had gone to great lengths to avoid the Empire on Tatooine. It wouldn't make sense to Obi-Wan to just sit back until the Empire had captured them in a tractor beam.

Obi-Wan was not privy to what was in R2D2

He scarcely recognizes the droid when he first sees him in ANH. Remember, Leia's recording does not say what information R2D2 contained, only that it was "information vital to the survival of the Rebellion". For all he knows, it could just contain plain old ordinary intelligence. It's not until Leia tells Han and Luke what he's carrying that anyone else (still alive at any rate) knows what he has in him. We never see Obi-Wan try to get at the information itself.

The Death Star was still a closely guarded secret

They've spent years building it and only, once it's ready to be used, do they start doing so in public. Han is incredulous at the size

HAN: It's too big to be a space station.

So a hermit on Tatooine will know more about this than a smuggler who regularly gets gossip?

The Death Star would have been exceptionally hard to destroy from within

It is not unreasonable to think that Obi-Wan could have discovered potential weaknesses in the battle station that he could have exploited in order to destroy the Death Star, but, he never did because his priority was to save Princess Leia and his new friends and honor a old one (Leia's father)'s request

You're right that he wanted to save his friends (Luke in particular), but the idea that Obi-Wan could have gotten access to a critical area of the station without being detected doesn't square with how he moved about. Obi-Wan sneaks around to avoid detection and gains access to areas of the station that aren't very well guarded. It's only once he realizes there's a trap waiting for them in the hangar that he baits Vader into finding and fighting him, which draws the guards away from the Falcon.

Anywhere that could destroy the ship would likely be some sort of engineering area, and would have taken a lot longer to both access and then execute any plan resulting in destruction (in both Death Stars, the only thing that does that trick is the main reactor exploding). Then you have to hope that any commands to the system(s) can't be overridden somewhere else in the station. Finally, you have to hope you won't be overpowered in said location before the main reactor goes critical. That would require intimate knowledge of how the Death Star worked (far more than even some cursory scan of the schematics would afford you) and an inordinate amount of luck to ensure it wouldn't be undone.

Answer 3

No, and he doesn't need to

His spiritual advice to Luke was to "Use The Force", merely encouraging Luke to trust his feelings more than his targeting computer (which already proved to be imprecise moments before) in a moment of high-stakes tension.