U-Boat Targeting Wheel

BROJD · 10-21-09, 07:15 PM

On p. 423 of Clay Blair's Hitler's U-Boat War: The Hunters, Blair writes that the rules and restrictions on U-Boats targeting ships during the first year of WWII were so complicated that the Kriegsmarine issued a special wheel device to sort out what could and couldn't be targeted.

Has anyone read or heard about this elsewhere? Does anyone have a photo or sample of one of these wheels? The Historian of the German Naval Association hasn't even heard of this.

GoldenRivet · 10-21-09, 11:29 PM

That would be the Kriegsmarine Glücksrad.

It was a circular device segmented into 8 sections with a rotating arrow affixed to the center.

The commander would spin the arrow with one good fling and it would point to a section when the arrow stopped whirling. Whatever option the arrow pointed at would determine the course of a pending attack situation.

the options which the arrow might stop on were:

1. Attack with the Deck Gun
2. Attack with torpedo while submerged
3. Attack with torpedo while surfaced
4. Let the ship pass by
5. Crash dive, go deep, go silent
6. Call the Luftwaffe
7. Be More Aggressive
8. Please ask again later

It was a very frustrating device to use as the arrow would often stop spinning between the options, forcing the commander to try again.

this cost valuable seconds in an attack situation.

Occasionally the option pointed to by the arrow once it stopped spinning wouldnt even apply to the given situation.

In February 1940, KaptLt. Johann Bernard, in command of U-101 had to spin the little arrow no less than 7 times before the arrow pointed to something vaguely appropriate to his situation.

strangely for the first 3 spins, it landed on "be more agressive", the 4th spin resulted in the arrow coming to rest upon the "Please ask again later" option.

After waiting approximately 7 agonizing minutes so that it would be "later", kaptLt. Bernard attempted to use the device a 5th time, this time it landed on "Call the Luftwaffe" however he was several hundred miles outside of any aircraft range.

On his 6th attempt the device frustratingly said "Please ask again later" once more.

The enfuriated commander dashed the Glücksrad upon the command room floor. this lodged the arrow on "Crash dive, go deep, go silent" therfore it was the only thing he was able to do for the remainder of the patrol.

as a result of the U-101 Glücksrad Incident, BdU collected up all of the Glücksrad devices and they were destroyed; commanders were told to take whatever actions they felt the situation demanded.

unfortunately not a single authentic example of the Glücksrad exists today

GoldenRivet · 10-21-09, 11:52 PM

An Artists conception of the Glücksrad device

U2222 · 10-22-09, 05:10 AM

Very creative...well done

RConch · 10-22-09, 06:23 AM

What kind of response is "Please try again later".
What is it, a freaking "8 ball".

Beyond Blair's book I have not run across a single reference to this item. I thought this was someone pulling his leg and discounted it as fake.
Thanks for bringing it up.

BROJD · 10-22-09, 08:51 AM

GoldenRivet -- Bravo. That certainly made my morgen.

Rconch -- Someone sent me some pictures of a Widmann'sche Prisenscheibe wheel that appears to be a targeting wheel for neutral and friendly merchants. I've sent it to the Historian at the German Naval Association for his take on it since my German isn't good enough to read the details.

10-21-09, 07:15 PM	#1
BROJD A-ganger Join Date: Jul 2007 Posts: 77 Downloads: 32 Uploads: 0	U-Boat Targeting Wheel On p. 423 of Clay Blair's Hitler's U-Boat War: The Hunters, Blair writes that the rules and restrictions on U-Boats targeting ships during the first year of WWII were so complicated that the Kriegsmarine issued a special wheel device to sort out what could and couldn't be targeted. Has anyone read or heard about this elsewhere? Does anyone have a photo or sample of one of these wheels? The Historian of the German Naval Association hasn't even heard of this.

10-21-09, 11:29 PM	#2
GoldenRivet Subsim Aviator Join Date: Mar 2007 Location: Texas Posts: 8,726 Downloads: 146 Uploads: 0	That would be the Kriegsmarine Glücksrad. It was a circular device segmented into 8 sections with a rotating arrow affixed to the center. The commander would spin the arrow with one good fling and it would point to a section when the arrow stopped whirling. Whatever option the arrow pointed at would determine the course of a pending attack situation. the options which the arrow might stop on were: 1. Attack with the Deck Gun 2. Attack with torpedo while submerged 3. Attack with torpedo while surfaced 4. Let the ship pass by 5. Crash dive, go deep, go silent 6. Call the Luftwaffe 7. Be More Aggressive 8. Please ask again later It was a very frustrating device to use as the arrow would often stop spinning between the options, forcing the commander to try again. this cost valuable seconds in an attack situation. Occasionally the option pointed to by the arrow once it stopped spinning wouldnt even apply to the given situation. In February 1940, KaptLt. Johann Bernard, in command of U-101 had to spin the little arrow no less than 7 times before the arrow pointed to something vaguely appropriate to his situation. strangely for the first 3 spins, it landed on "be more agressive", the 4th spin resulted in the arrow coming to rest upon the "Please ask again later" option. After waiting approximately 7 agonizing minutes so that it would be "later", kaptLt. Bernard attempted to use the device a 5th time, this time it landed on "Call the Luftwaffe" however he was several hundred miles outside of any aircraft range. On his 6th attempt the device frustratingly said "Please ask again later" once more. The enfuriated commander dashed the Glücksrad upon the command room floor. this lodged the arrow on "Crash dive, go deep, go silent" therfore it was the only thing he was able to do for the remainder of the patrol. as a result of the U-101 Glücksrad Incident, BdU collected up all of the Glücksrad devices and they were destroyed; commanders were told to take whatever actions they felt the situation demanded. unfortunately not a single authentic example of the Glücksrad exists today __________________

10-21-09, 11:52 PM	#3
GoldenRivet Subsim Aviator Join Date: Mar 2007 Location: Texas Posts: 8,726 Downloads: 146 Uploads: 0	An Artists conception of the Glücksrad device __________________

10-22-09, 05:10 AM	#4
U2222 Sparky Join Date: Feb 2006 Location: High Peak, UK Posts: 156 Downloads: 43 Uploads: 0	Very creative...well done __________________ A Big Thank You To All The Modders Who Make Sub Simming Such A Deep Experience

10-22-09, 06:23 AM	#5
RConch Captain Join Date: Jul 2002 Location: No. Virginia Posts: 619 Downloads: 518 Uploads: 0	What kind of response is "Please try again later". What is it, a freaking "8 ball". Beyond Blair's book I have not run across a single reference to this item. I thought this was someone pulling his leg and discounted it as fake. Thanks for bringing it up. __________________ "Noch und Noch" Prowling the Nord Atlantik with GWX 3.0.

10-22-09, 08:51 AM	#6
BROJD A-ganger Join Date: Jul 2007 Posts: 77 Downloads: 32 Uploads: 0	GoldenRivet -- Bravo. That certainly made my morgen. Rconch -- Someone sent me some pictures of a Widmann'sche Prisenscheibe wheel that appears to be a targeting wheel for neutral and friendly merchants. I've sent it to the Historian at the German Naval Association for his take on it since my German isn't good enough to read the details.

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