So for some reason I'm drawing a blank here. How do you narrate failed Astrogation checks to plot a course?

Do you allow your players to retry?

Any suggestions would be hugely appreciated, thanks in advance!

Typically, if there is no Despair, but failure, the Navicomp will reject it. Just like if you put an address that does not exist in your navigation unit. If threat is rolled, but they have success, you can tac on some extra time to the trip. Both Fail, and threat, then they have to redo it, and now the check will take longer. Failure with advantage, the trip didn't take, but they see their mistake, and redo the roll with a boost, or reduced time on the skill check.

Triumph, the set a new record for that run. Or found a new faster path.

Despair, they might have flown in to close and damaged the inertial dampener, or even the hyperdrive. Multiple Despairs in one roll...they might get lucky and have just enough time to make to escape pods before the ship breaks apart or blows up.

Or, in a slightly less fatal scenario, the navcomp is cooked on multiple Despairs. If your PC's aren't on a deadline, then an Astrogation check would be unnecessary. If you're keeping track of time (such as the PCs needing to be someplace in time) or during a combat encounter (being harried by TIEs or pirates), then an astrogation check should take several rounds. Failure could mean doing it all over again. Failure and threat can mean the computer crashes and has to be rebooted, delaying you a round before you can try again, success and threat means it takes an extra round or so before you can get out of Dodge, and so on and so forth.

If it's in combat I say that they are so stressed that they put the wrong numbers in, like they accidentally hit the wrong button at some point while typing and they have to do it again.

Outside of combat I say the computer is having trouble due to a large amount of traffic and they need to find a different route by trying again.

And if they fail too many times I just say "forget it" and they arrive slightly late.

Easy. The ship makes the jump to Hyperspace but . . . .

- They use more fuel that expected resulting in higher restock fees at the destination

- The trip takes longer

- The route is interdicted by a customs checkpoint

- The Arrival Warning system doesn't ping and they overshoot their destination

- Hey, that's Bespin not Coreliia!

- There's a rattle in the engine that they cant identify

- Something is wrong and the ship vibrates ever so slightly, making it impossible to sleep.

Just watchTESB it has plenty of astrogation failures. Here's another example;

Admiral Ozzel : [ appearing onscreen with Captain Piett ] Lord Vader, the fleet has moved out of lightspeed and we're preparing to...
[ Ozzel stops, and suddenly begins to choke, clutching at his throat ]
Darth Vader : You have failed me for the last time, Admiral! Captain Piett?
Captain Piett : Yes, my lord?
Darth Vader : Make ready to land our troops beyond their energy field, and deploy the fleet, so that nothing gets off the system.
[ beside Piett, Admiral Ozzel utters one last strangled gasp, and falls over dead ]

First of all, I only have my players make Astrogation checks when the result matters; as in, if they're trying to escape pursuit, or are under a time limit to get where they're going, or they need to emerge in precisely the right spot. But if the check results don't matter to the story, I just handwave it.

This actually makes it much easier for me as a GM to determine what the various symbols mean in a given situation. For example, if the players are fleeing Imperial pursuit successes means it takes fewer rounds to calculate the jump, while failure means it takes longer. Which gives the Imperials more time to shoot at them. If they're in a hurry to get someplace, failure can mean they emerge in the wrong place (either too far out from their destination planet, or in the wrong system alltogether) while Threat means the actual travel time takes longer. And for precision jumps failure means they miss their mark, with whatever consequences that has in the given situation.

They end up in a different place than they intended or in the middle of an astroid field. Maybe they fly out of Hyperspace and crash on a known or unknown planet in the middle of nowhere. Maybe they damage the ship somehow.
On a despair, the hyperdrive may be damaged beyond repair.

Make it interesting and fun! Don`t let failures end the game or result in a stand-still. The show must go on!

First of all, I only have my players make Astrogation checks when the result matters; as in, if they're trying to escape pursuit, or are under a time limit to get where they're going, or they need to emerge in precisely the right spot. But if the check results don't matter to the story, I just handwave it.

This actually makes it much easier for me as a GM to determine what the various symbols mean in a given situation. For example, if the players are fleeing Imperial pursuit successes means it takes fewer rounds to calculate the jump, while failure means it takes longer. Which gives the Imperials more time to shoot at them. If they're in a hurry to get someplace, failure can mean they emerge in the wrong place (either too far out from their destination planet, or in the wrong system alltogether) while Threat means the actual travel time takes longer. And for precision jumps failure means they miss their mark, with whatever consequences that has in the given situation.

I do this as well, however the one sticking point has been when they're trying to explore a new route or such. I don't want to handwave something so potentially important, but rolling over and over can be a pain. Of course, any explorer worth their salt should have more than a rank in Astrogation!

I GM with the idea that Success should not be required to progress the story, if they fail then there should still be a suitable resolution and no need to re-roll, there fore I use Krieger22's method for Astrogation. After all making them roll again just to succeed Can bring players out of the story too easily, especially when you can just say "well this is going to take the Nav Comp a while, I'd say (insert number of rounds/minutes/hours here to suit the scene). You can leave it to its task and help the others deal with your immediate threat."

But I try to apply this thinking to all skills, I didn't take the time to develop a story where not finding a particular clue ends the adventure!

Of course if they are searching for cred sticks or loot then failure will mean only a paltry haul.

This method also avoids the awkward "Move over, give me a try even though my Dice pool is half of yours" moments.

First of all, I only have my players make Astrogation checks when the result matters; as in, if they're trying to escape pursuit, or are under a time limit to get where they're going, or they need to emerge in precisely the right spot. But if the check results don't matter to the story, I just handwave it.

This actually makes it much easier for me as a GM to determine what the various symbols mean in a given situation. For example, if the players are fleeing Imperial pursuit successes means it takes fewer rounds to calculate the jump, while failure means it takes longer. Which gives the Imperials more time to shoot at them. If they're in a hurry to get someplace, failure can mean they emerge in the wrong place (either too far out from their destination planet, or in the wrong system alltogether) while Threat means the actual travel time takes longer. And for precision jumps failure means they miss their mark, with whatever consequences that has in the given situation.

I do this as well, however the one sticking point has been when they're trying to explore a new route or such. I don't want to handwave something so potentially important, but rolling over and over can be a pain. Of course, any explorer worth their salt should have more than a rank in Astrogation!

I actually had this happen not so long ago in my EotE campaign. The players signed on as deep space explorers blazing a new hyperspace route into a vast nebula. I put the base difficulty at Hard, upgraded twice because of the various hazards you can run into when jumping blind, and then with three setback dice on top of that to illustrate a never-before travelled route.

Of course, since this was a big part of the adventure I had prepared unique tables for what to do with up to 5 Advantage or Threat as well as Triumph and Despair. Failure meant things took longer, and since they only had so much consumables this would mean less time to explore in the nebula before having to return and resupply. It all worked out pretty well, and the next time we play that campaign they're heading back in to explore further.

For me, I look at it like this. A bad astrogation jump can entail the following:

1.) Can't find up to date jump data for the planet. Can't program coordinates and calculate the jump. Wasted time, must get the updated data (this is especially useful when they fail while jumping mid-combat).

2.) Data entered wrong, cannot jump. (again, useful in mid-combat to make them start the check over, or to instead make a computers check to find and fix the data entry mistake).

3.) Data entered wrong, did jump. (Here you let them get away, but now you can have them come out of hyperspace in a weird location, or suffer some kind of astrogation mishap halfway there that damages the ship, or drops it out of hyperspace in a nest of pirates, nebrays, a black hole, whatever).

4.) Equipment failure. (you pushed it too hard, and now the hyperdrive busted. Mechanics check in back of ship to repair. You have to clean the ship, Chewie. Do you want mynocks? that's how you get mynocks!).

5.) Wrong planet. (Some planets have similar names or coordiantes, the party can show up at the very,very wrong place unexpectedly. )

6.) Detour (It might take the party much longer to get there, which can cause htem to miss a contact or rendezvous, or make their contact upset with them for being late (upgrading difficulties of checks)

That said, most astrogation checks for routine travel shouldn't be very hard, or shouldn't even require a check. The only time I'd require an astrogation check for a hyperspace jump is when the check is being made under duress, or when time is a major factor, so the speed with which people arrive is an important thing to keep track of. If the PCs are just traveling and it's not a race or under stressful circumstances, I'd jsut allow them to jump.

The other point to consider is how failed are we talking? Just bog standard no successes? Hey look, you forgot to carry the one, your nav computer suffered a blue screen of death and has to reboot - you're going nowhere and you take a bit more time to recalculate. No big deal, unless you're under fire, of course.

With the threats, that's when you start piling on the little things. They use more fuel and the trip costs more, the trip takes way longer and so on. Save the big things - off course into an imperial stronghold, bouncing too close to a supernova, expensive and time consuming repairs to the hyper-drives - for the despairs.

Thanks everybody. Some brilliant suggestions here.

Biggest takeaway for me...if it's not important to the story, don't bother with the check.