Just completed a patrol where my assigned area was GR69 -- about as far away as possible with our current map.

I intended to go just to see the world down there -- but I intercepted two convoys before I got a third of the way there and ran out of torps.

So I had to go home to pick up some more.

Has anybody actually made it down there yet?

... because it wasn't clear to me that my Type IXC had the range to make it there and back without refueling somewhere.

Maybe this is stating the obvious but If you travel at 1/3 instead of standard speed your range increases hugely.

Yes, I had noticed that the "knee in the curve" for fuel consumption vs range seems to be about 9 knots, depending on sea state.

From Lorient to GR69 is about 13000 km or so, and the best range numbers I could project were about 32600 km -- and then only if I behaved myself and kept the boat slow.

After running intercepts on two convoys, I had spent about 3 days at flank or full speed, reducing my fuel enough that it didn't look like I could make it down there and back.

I suppose if you don't get frisky with the throttle you could make it.

Ive made it to off the Florida coast, sank an unescorted tanker with no armanents. Couldnt hang about though. Made it back to Lorient with aout 2% fuel.. Must go slower on my next trip to the US.

Each boat/engine combination seems to have a sweet spot, a speed which yields the greatest range. For example my testing shows a type VII with the standard engine (ie no supercharger) gets around 24,000km at 7kts. A VII with the MAN engine (exhaust supercharger) gets around 16,000 at 9kts.

Any speeds faster or slower results in les range. Range determined using the navigator range reports.