Maximizing range/time on station

[grislyatoms]

What measures do y'all take?

FWIW, I am patrolling from Pearl. I'll run standard to Midway, top off the tanks, then run* to just east of the Okinawan (archipelago?) string of islands. Lots of good traffic there. Can't spend a whole lot of fuel there (just under 1/4 of a "tank", as I need just over half to get back to Midway). On station, though I use fuel somewhat unrestricted. If I need to run at flank to get in a good position, I will.
It's interesting to send in a patrol report and hear "Okay, proceed to South China Sea and intercept shipping there." No can do, subpac, not enough fuel.

* I run ahead slow until the batteries are recharged, dive until they are depleted, surface, ahead slow until they are recharged, rinse and repeat. Seems to give me the best range.

Any tricks/other strategies?

[Torplexed]

Originally Posted by grislyatoms

I run ahead slow until the batteries are recharged, dive until they are depleted, surface, ahead slow until they are recharged, rinse and repeat. Seems to give me the best range.

That strategy may be costing you range. When you're fully re-charging batteries all the time one set of diesels is devoted solely to that task costing you mileage and range. You range you get underwater from the batteries doesn't make up for what you are losing on the surface. You best bet is to remain on the surface as much a possible using batteries only in an emergency or an attack. That's what the superlative air-search radar is for. You don't have to crawl underwater for hours like U-Boats did because aircraft are less of a threat.

[grislyatoms]

Hmm, I wondered about that.
On my way back from photographing Hiroshima bay, 2nd patrol, I couldn't reach Midway even with just over 1/2 fuel left. I tried every speed setting possible. Granted, I had taken some damage from one of the coastal guns, but the diesels/fuel tanks were intact, to my knowledge.

The only way for me to get to Midway was doing what I described. Any other method and I was out of fuel 700-800 miles from Midway.

[Saturnalia]

Running at 10-12 knots seems to be the most fuel efficient setting. How long are you staying out there?

[Torplexed]

Your best bet is not using anything higher than 8-9 knots when on long missions and you're not pursuing a target. You should be charging batteries at 1/3 speed so they charge at a fast rate, thus when they are charged, you will get maximum speed.

Ironically, if you go slower than the standard setting you'll burn more fuel because your diesels are using fuel at a higher rate than you are moving through the water.

[Brenjen]

Charging batteries uses more fuel, running above or below standard uses more fuel. I use standard for everything on the surface & 1/3 for everything submerged with very few exceptions. Use everything else sparingly & you'll never run out of fuel.

That's with RFB, vanilla never seemed to run out of fuel regardless of what I did lol

[razark]

Originally Posted by grislyatoms

Hmm, I wondered about that.
On my way back from photographing Hiroshima bay, 2nd patrol, I couldn't reach Midway even with just over 1/2 fuel left. I tried every speed setting possible. Granted, I had taken some damage from one of the coastal guns, but the diesels/fuel tanks were intact, to my knowledge.

The only way for me to get to Midway was doing what I described. Any other method and I was out of fuel 700-800 miles from Midway.

Did your batteries get damaged? I took damage to my forward batteries off the coast of Japan, and every time I asked, I was told the range to Midway was too far for my current fuel usage. Eventually, I noticed the batteries were still charging, even though they wouldn't take any more charge.

Switched to standard propulsion, and Midway was no longer out of range.

Razark

[grislyatoms]

Sounds like a case of me putting 2 and 2 together and coming up with

I knew about the recharge at 1/3 (says as much in the manual) but was assuming slower = less fuel used regardless.

There had to have been something damaged, then, on the boat if things are as y'all say. Running diesels only I should have been able to make Midway.

Did your batteries get damaged?

That's possible, I suppose, but then I think using the electrics would have worsened the range situation, not improved it.

Okay, that begs a couple of questions.

1. When y'all leave from Midway (assuming you top off your tanks there) and arrive just off the Japanese/Okinawan coast, how much fuel have you used?
2. All things being equal, if it takes me 1/2 my fuel to get to a certain point, I should be able to return to my starting point with the other half? Or is their something I'm not accounting for or have overlooked?

In any event, thanks for the tips/advice. I'm going to try running standard/surface and see if I get an improvement.

[Inner Sound]

In the Balao I'll arrive off Japan with 70% to 75% fuel left from Midway.

[Brenjen]

I go from pearl to Japan, patrol & return to pearl 99% of the time with no stop offs at Midway either on the way out or back in. That said I usually have very little fuel left.

When I leave from & return to Midway on a patrol to Japan I usually have a 1/4 tank of fuel left.

Recharge your batteries @ standard speed & see if that doesn't make all the difference.


(I use RFB & RSRDC btw)

[Akula4745]

Also remember you can turn battery charging off to save fuel... if you get down to the nitty gritty. Every since I adopted the standard 10.5 knot surface speed I have not had any fuel complications.

[Munchausen]

No Damage

• Recharge batteries at 1/3 speed.
• Cruise on the surface at 10 knots.

Any Damage

• Determine max battery charge (usually less than 100%).
• Charge batteries at 1/3 speed.
• Manually disengage batteries when "full."
• Cruise on the surface at 10.