The airplanes in FotRSU are, for the most part, TMO v1.7, with some "improvements" in the AI_Kill-ability (like they're on steroids)... They used to calls the airplanes in TMO "Ducimus's Evil Airplanes". In FotRSU beta v0.63 (Fall of the Rising Sun v2 basically), they are "AOTD_MadMax's version of Ducimus's Evil Airplanes"...
In other words, they are bumped-up a bit. The thing to do is to have your air search radar on all of the time, even if the Japanese have radar detection by then. Do like Rockin Robbins does in that tutorial video above, only make the circle bigger for FotRSU. I've been using 10nm lately. This means that as soon as a plane is detected, you need to determine how close it is going to come to you. If it looks like it'll be within about 8.6-9.2nm, dependent upon the weather, crash dive and get down to 150 foot. Rockin Robbins stays down for about five minutes. With that longer range you might use in FotRSU, you should give them 8-10 minutes before you come up to PD at "Ahead One Third" - no faster than that - before you stick your scope up for a look-see. If you "see" a plane, check the Nav Map asap, and figure-out where he is and which way he's going. Take her back down to 150 for a bit longer if it's close. Don't hesitate. If you hear bombs, do like below and change course and stay down for 30 minutes or more. If you don't see anything, come up to radar depth, again at no more than "Ahead One Third". You go faster, you'll kick-up too much wake, and that will be seen. You should "see" the plane on radar still, hopefully traveling away. Once he gets out of that 10nm circle, ~then~ you can come up and do it all over again. Take it up to Ahead Standard once you're up top, and recharge them batteries.
If during your first encounter with a plane, they happen to "see" you (pay attention to if they turn toward you), after you crash dive and get down to 150 foot, change course at least 15 degrees and then do no more than "Ahead One Third" (again). This time though, stay down for 30 minutes or more. Come up cautiously again, checking the periscope before coming up to radar depth, and again - go no faster than "Ahead One Third"! You want to be moving, just in case you have to dodge something, but not moving so much that you disturb the water surface so much. The thing is, once you're seen, the one plane will call all of his nearby buddies, and they'll all come trying to find you now, and get a piece of your boat, so they will basically swarm on you for a while. If there is a carrier nearby, they have a tendency in the game (stock included) to launch all that they have at you. It generally takes 30 minutes for them to lose your scent, and maybe then, the AI will reset to no detection... but these are planes, and it can take them a bit to respond sometimes, and they will generally go to a location further up your last known route. Once you're seen, it might take until dark to get them off your trail, hence the course change, and not doing more than Ahead One Third while under. If you're seen again, change course again. Once nightfall hits, resume your original course, only now, make sure you've not altered the course so much that you'll run aground on reef or island, like someone else we know...
In TMO, the planes can "see" your boat down at 100-120 feet. Figure that a little deeper in FotRSU. The current airplane behavior will be part of an overall AI behavior mod choice, once we get things set for finalized release. We're not sure how we'll configure the AI choices just yet, but there will be at least an "Easy" and "As-is" setting. In real life, the planes were extremely dangerous and were not trifled with by most US boats. FotRSU has its planes set like that, only they might be a bit thicker than real life, once there is a detection of your boat, but read some of the patrol reports of real subs, and you'll find that having five and six encounters a day was not all that unusual in some areas...
