Wait till you get the XXI later in the war. No special cautiousness needed.
Instant invisibility.
I'm on my 49th patrol and have the XXI since 5 patrols (march 45, war will be over after the next patrol).
I've never felt so untouchable. And I don't use it's great submerged speed at all. It really seems that this sub is invisible to the enemy. Totally clueless escorts while I decimate the convoy.

TBird

WOW TBird....That is TOTALLY opposite of what I am experiencing.....I'm in February of 1945, in a type XXI on my 40th patrol, and EVERYONE sees me. The aircraft, the DD's, everyone.
I have to travel at TC-16 when snorkel up at depth, or I'm dead instantly, by the AC. Snorkel is useless, they spot it on radar when I'm anywhere near an aircraft. I travel at only 5kt or less.
With the radar destroyed bug on the type XXI, I don't have radar on my snorkel.
I can't let a DD get within 1-2000 yards, or he sees me, and calls his buddies...once they spot me, they never lose me, whether I'm 14m stopped or 275m and silent/stopped.....I'm dead.
I have to kill everyone before they get within 500 meters, or it's too late, they're under the guns, and I'm dead.

My only ace is the speed to 'move' over.
But once they lock onto you, they DON'T lose you.
Eventually they always win.
The only answer is to stay away from them.
FAR away....kill anything within 2000m....or your dead.
If they stumble onto you....they see you, your DEAD, and if you try to move away....they see you, your DEAD.
That's my experience.

WOW what a difference!

Mid `41 in a IXB for me - 36 patrols (tweaked "time in port" from 28 down to 5 days)...
Already I have noticed the escorts are getting more on the job, if I ever make it to `45 I think I`ll be lucky. (also no doubt a nervous wreck in RL)

The game is not wearing off for me, but when before I used to go in with `all guns blazing` - now I sit back more and observe before committing my boat and crew

Good Hunting to all other Kapitans out there

Mid `41 here also, 33 patrols in U-48 same boat I started with Type VIIb. Been pretty lucky so far. Games not wearing off, just more things to do this Summer, plus other Sims I`m playing. The escorts are getting more plentiful, and tougher. Still play as much as I can. Good Hunting. Puts

Strange that my experience is so different.

Some examples of this experience:

-A few patrols ago, I attacked a fairly big convoy s/w of ireland. Calm weather and daylight. I waited submerged in his path.
When he arrived, the leading destroyer crossed in front of me at approx. 1700meters. I couldn't resist sinking him with an acoustic torp. Then I started the engines and headed towards the convoy (silent). A destroyer that covered the side of the convoy was at 160degrees, distance 3000-4000meters. He accelerated after his friend exploded but never came near.
I then fired 3 torps, one at a T3, one at a T2 and one at a troop transport. All 3 hit, but none of them sunk. They just stopped. I decided to sink them later and marked their position on the map.
Meanwhile, I was in the middle of the convoy. There I could, without ever been detected, take out some libertys and victorys. And believe me, I had the periscope up for quite some time (never fully, though).
The destroyers reacted, but they never drove into the convoy to search for me. I was able to sink another one that crossed in front of the convoy (I love those acoustic eels!).

With 4 torps left to sink the previously damaged ships, I dove to 80meters, turned around 180 degrees and headed into the direction of the 3 damaged ships.
I once heard a ping of one of the destroyers that came too near, but the pings lasted only 30seconds and then he was gone to protectthe convoy.
As I reached the first damged ship, the convoy and the escorts were about 7km away, barely visible.
After I sunk the T2, a destroyer headed towards our position, but gave up after a short time (I was already on the way to the 2nd ship which was about 6km away). I sunk the 2nd ship, but this time no destroyer reacted.
I then proceeded to the last one. As the convoy was out of sight by this time, I raised the snorkel. As I manouvered into a good 90degr. position to finish off the last tanker, I suddenly heard explosions.
I raised the periscope and saw several planes throw bombs about 1km away (don't know where they came from).
Although I had the snorkel up for quite some time, the didn't seem to see me (they bombed something, but definately not me).
I lowered the snorkel and continued towards the tanker. Just to see what would happen, I drove with raised periscope all the time. They didn't see this either.
I finally sunk the tanker and set course to bergen.

(ooops....this story got longer than I intended)

-3 patrols ago, I drove more than 2 days submerged with the snorkel up, totally unharmed. It was west of ireland.

-one time, I followed a fast convoy, snorkel up. I checked the position of the convoy from time to time with the periscope. On one of these occasions, I thought it would be good to make a 360degree check.
Oooops...a destroyer about 2km away on 70degrees. So I lowered the snorkel and ordered 100m. At 50meters I released a "Täuschkörper" (english word?) and prepared to be DCed.
To my surprise, nothing happened. Once again, the destroyer hadn't seen me.

-planes: I've never been attacked by planes while submerged and snorkel up. Nor have I been surprised by planes on the surface (in the XXI, the VIIc was totally different).

Possible explanation: whenever I get the message that radar emissions are detected, I immediately order periscope depth. I then ask for the nearest sonar contact. If there's none, the radar emission came from a plane and I dive to 50meters at full speed, changing direction.
If there's a sonar contact, it's a destroyer and I change direction 90 degrees and dive to 80 meters in silent mode (most of the time, the detroyers are far away at this moment, so no worries).
This has always worked so far.

Uuuh, long post. But hey, I post from work

Finally, some infos about my game:
I'm still using v1.2 with the Wmod2.02. Not much more (some sounds and officer fatigue removed)

Greetings
TBird

Edited for spelling and some content

"Your version of 'dynamic' makes me think that you are a flyboy...."

Hahaha....I'm busted. Former Air Force...and Army....but NOT a pilot (although I have had sensor operator time in a modified C-337).
Actually....in all honesty I used to be terrified of flying and barfed almost every time I had to go up in a helicopter (Hueys when I first went in and Blackhawks later on). I even managed to toss cookies aboard a KC-10 flying from Ellsworth AFB back to Offutt AFB when the pilot gave us a peek at Mt Rushmore-it's a wee bit bouncy around those parts . When I started feeling green the gas-passer gave me an envelope and told me to use that--not knowing that there was a barf bag inside I promptly overflowed that all over myself, the refueling technician, and that nifty boom-operator gear :p . It's a bit ironic that after close to 3/4 of a million corporate air miles later I usually sleep like a baby these days. Perhaps I would have done better with a double Bailey's on the rocks pre-flight back in those days
Of course when I cross-trained into PMEL and actually learned how aircraft flew and got into simulations I found that helped as well!

Regards
SGT_Rock
Former "scope-dope" and "sparkchaser"
USAF/USA

Gonna re-install SHIII