RTB speeds.

rudewarrior · 04-13-10, 10:35 PM

Hi.

Read quite a few books on the Atlantic War, but I didn't see anything on this particular subject. I'm curious about the speeds at which they returned to their bases. I assume that they would return at top speeds in order to get the weapons platform reoutfitted as quickly as possible, and back to fighting. However, would this cause engine issues?

I never found any references to it in the books I have read so far. They only talk about having enough fuel "to get home." Yeah buddy, I know. But how fast?

Thanx.

timmy41 · 04-13-10, 11:20 PM

considering the ranges at which they operated, I seriously doubt they could RTB at anything beyond cruising speed without having a bit to spare for bad weather and detours. Plus, all machines fail, especially ones that are used almost 24/7, and were built by rushed industry that may not have had all the proper tools available at times. There are not always spare parts available, so one does not want to risk any frivolous damage from running a machine too hard too long that may not allow them to get home at all. on top of all that and more, this is the 40s, and lots of these things were designed in the early 30s.

brett25 · 04-14-10, 01:31 AM

i just finished reading Iron Coffins by Herbert Werner, you can read here that many of the u boat casualties later in the war were the U boats returning to their bases in the Bay of Biscay. The allies were waiting for them and the uboat's last leg home often became a turkey shoot for the allied aircraft. So depending on how you opted-either you returned slowly under water, undetected, or all out full throttle running the gauntlet. Either way your chances were not good, as, on average, only one out of every four boats would make it back.

HW3 · 04-14-10, 02:49 AM

I doubt they would have had enough fuel left, after patrolling for several weeks, to return to base at anything other than regular cruising speed.

Weisia · 04-14-10, 04:55 AM

If I remember correctly the engine would overheat in SHII if you use flank speed to long. Seems quite logical to me that if you use a diesel in high RPM for a long period of time that the possibility of a break down increases.

Jimbuna · 04-14-10, 06:41 AM

Quote:

Originally Posted by HW3

I doubt they would have had enough fuel left, after patrolling for several weeks, to return to base at anything other than regular cruising speed.

Agreed....flank speed was only used for convoy interceptions and for as short a period as possible because of the wear and tear/maintenance issues it created.

sharkbit · 04-14-10, 07:44 AM

Quote:

Originally Posted by jimbuna

Agreed....flank speed was only used for convoy interceptions and for as short a period as possible because of the wear and tear/maintenance issues it created.

It sounds like those diesels could be maintenance nightmares.
I'm reading Clay Blair's "Hitler's U-Boat War:The Hunters" and it is filled with instances of boats aborting patrols due to engine problems.

04-13-10, 10:35 PM	#1
rudewarrior Sonar Guy Join Date: Apr 2005 Location: Middlebury, VT, USA Posts: 378 Downloads: 165 Uploads: 2	RTB speeds. Hi. Read quite a few books on the Atlantic War, but I didn't see anything on this particular subject. I'm curious about the speeds at which they returned to their bases. I assume that they would return at top speeds in order to get the weapons platform reoutfitted as quickly as possible, and back to fighting. However, would this cause engine issues? I never found any references to it in the books I have read so far. They only talk about having enough fuel "to get home." Yeah buddy, I know. But how fast? Thanx.

04-14-10, 01:31 AM	#3
brett25 Seasoned Skipper Join Date: Mar 2008 Location: Oakland CA, USA Posts: 737 Downloads: 570 Uploads: 0	i just finished reading Iron Coffins by Herbert Werner, you can read here that many of the u boat casualties later in the war were the U boats returning to their bases in the Bay of Biscay. The allies were waiting for them and the uboat's last leg home often became a turkey shoot for the allied aircraft. So depending on how you opted-either you returned slowly under water, undetected, or all out full throttle running the gauntlet. Either way your chances were not good, as, on average, only one out of every four boats would make it back. __________________ http://shmf.larsbundgaard.dk/index.p...1tn5&board=7.0 Last edited by brett25; 04-14-10 at 02:39 AM.

04-14-10, 02:49 AM	#4
HW3 Navy Seal Join Date: Apr 2005 Location: Gresham Oregon Posts: 6,575 Downloads: 458 Uploads: 0	I doubt they would have had enough fuel left, after patrolling for several weeks, to return to base at anything other than regular cruising speed. __________________ "Some ships are designed to sink...others require our assistance." Nathan Zelk

04-13-10, 11:20 PM	#2
timmy41 Weps Join Date: Mar 2010 Posts: 367 Downloads: 9 Uploads: 0	considering the ranges at which they operated, I seriously doubt they could RTB at anything beyond cruising speed without having a bit to spare for bad weather and detours. Plus, all machines fail, especially ones that are used almost 24/7, and were built by rushed industry that may not have had all the proper tools available at times. There are not always spare parts available, so one does not want to risk any frivolous damage from running a machine too hard too long that may not allow them to get home at all. on top of all that and more, this is the 40s, and lots of these things were designed in the early 30s.

04-14-10, 04:55 AM	#5
Weisia A-ganger Join Date: Jan 2009 Posts: 71 Downloads: 65 Uploads: 0	If I remember correctly the engine would overheat in SHII if you use flank speed to long. Seems quite logical to me that if you use a diesel in high RPM for a long period of time that the possibility of a break down increases.