May 23/24 night shadowing and interception approach CS1/BC1

[Antonio Bonomi]

Hello everybody,

@ Paul Cadogan

first of all we all hope that the " Super-Hurricane Matthew " will avoid to hit the islands and the population and will use his power on the sea, ... so we can have you always able to chat with us my friend ...

You raised a very important, ... I shoud say a fundamental point here Paul, ... that was surely one of the reasons of the many geographical positioning errors by the navigating Officers on the various warships, ... that of course became bigger and bigger as they did travel huge distances crossing several meridians ( very critical up there ) and parallels ( much less critical ).

This is the reason why I invite once again everybody to acquire as much as possible cartography ( Marcatore ) and navigation information in order to follow this thread.

Just a couple of confirmations for everybody to understand can be immediately realized by the fact that the Royal Navy Admiralty war room always wanted to know the precise geographical positions of every unit and whenever possible was cross checking them with someone else confirmation ( airplanes versus cruisers ) ... more, ... if you look above on the decoded messages link you will realize that there is on them the direct confirmation of what I am saying, because :

- Hood decoded msg at 05.43 communicated her being in position ( Point H ) : 63° 20' N and 31° 50' W

- CS1 (Norfolk-Wake-Walker) communicated at 06.37 that Hood was sunk in position : 63° 21' N and 31° 41' W ( 31° 47' W for David Mearns ) while at 06.15 he did communicate that Hood was sunk in position : 63° 20' N and 31° 50' W ... ... which is the exact Hood communicated position at 05.43 ...


Of course on the Norfolk they were sure ( highly confident ) of their own geographical positioning on that moment, but unfortunately they were a lot more incorrect than on board the Hood ( Commander Warrand was just perfect about it ), and in fact as you can easily realize by comparing the 2 geographical positions, ... they communicated the sinking place being a North East position compared to the Hood position at 05.43 ... ...which of course is impossible given course and speed ( to west ) sailed by the Hood from 05.43 until 06.00.

Now you can realize 2 things easily, ... why the Admiralty war room always wanted geographical position confirmations, ... and why David Mearns trusted immediately Commander Warrand ( correct ) and NOT the Norfolk information ( surely incorrect ).

There is for sure a tolerance margin we need to take in account while doing this work, ... and we all must be aware about it, ...so your point is correct, the sea current as well as the cartography tolerances are variables, like the real speed and their fixed point last reference with ground or stars, ... but for our purpose, ... there is one thing will help us a lot, ... and it is the cross checking of the bearings among the various warships.

It is by cross checking the bearings among all warships and knowing precisely some positions ( Hood wreck is the most important here because it is perfect ) we can reproduce backwards the all ship tracks from 06.00 of May 24th, 1941 ... until the 19.22 of May 23rd, 1941 when Able Seaman Newell on board the HMS Suffolk saw the Bismarck and the Prinz Eugen for the first time in the Denmark Strait minefield communicating their geographical positions from her own being : 105 JBAH 4.

We need to re-construct the tracks from meridian 24 until 32, ... so crossing 8 meridians and from above the parallel 67 until parallel 63 , ... going down 5 parallels too.
It is a rectangular area large around 200 sea miles ( 25 sea miles average meridian width times 8 meridians 25x8= 200 ) and 300 sea miles high ( 5 parallels crossed with each parallel being 60 sea miles width so 5X60 = 300 ).

On the around 10-11 hours we are talking about ( from 19.23 until 06.00 ) sailing at an average speed of 28 knots, ... they covered more or less 280-290 sea miles inside this area in a diagonal run.

I invite everybody to acquire as many information as you can about this area, because the knowledge of it will be fundamental to understand the all reasoning we are going to make.

I made a real paper map in scale of course, ... if you do it, ... this will surely help you too, ... ... than I have my computer map as well, ... using the Mercatore projection.

https://en.wikipedia.org/wiki/Mercator_projection

Bye Antonio

[wadinga]

Hi Paul,

Good luck with the storm. Tropical weather has both general benefits and specific nasty negatives.We all need to remember these ships were experiencing real weather conditions and are not just mathematical graphing exercises.

Windeage on the hull and movement of the water mass do confuse DR. Different vessels experiencing different conditions with different navigators get different results. We have established Suffolk was reporting a position 14/20 miles wrong. We know Prinz Eugen and possibly Bismarck were 90 miles out.

However if Hood's DR was so close to the wreck site and we know PoW's reported offset to Hood then the track is probably quite good.

As to Norfolk's navigational error, do we have any idea, based on the position they gave for Hood's sinking compared with the wreck site?

Antonio is right about bearings but there are bearings and bearings. The bearings on PoW salvo plot are visual gyro relative bearings and are high quality. M/F D/F are far lowere angular accuracy and a few unjustified lines on a chart with no provenance are extremely suspect and may be no more than guesswork.

Alberto, the tracks leading up to Denmark Straits are part of this thread. You keep telling Wake-Walker what he should have been able to see because he was 19 miles from something. Some smoke? Even were the analysis to prove the BCF was within 19 miles or 20 or 25, just because a different person looking at a different thing in different conditions can identify something, it proves nothing. Norfolk logged the BCF at 05:50!

All the best

wadinga

[Antonio Bonomi]

Hello everybody,

@ Wadinga,

YES, you are right Sean and I agree with you on this :

We all need to remember these ships were experiencing real weather conditions and are not just mathematical graphing exercises.
Windeage on the hull and movement of the water mass do confuse DR.
Different vessels experiencing different conditions with different navigators get different results.
We have established Suffolk was reporting a position 14/20 miles wrong.
We know Prinz Eugen and possibly Bismarck were 90 miles out.
However if Hood's DR was so close to the wreck site and we know PoW's reported offset to Hood then the track is probably quite good.

The Hood and PoW track above is quite good ... ... Suffolk error growing thru the time, reaching the range of 20 to 30 sea miles, ... an entire meridian to meridian distance up there.

You asked :

As to Norfolk's navigational error, do we have any idea, based on the position they gave for Hood's sinking compared with the wreck site?

YES, ... I do, ... it is around 10 to 15 sea miles.

Both Norfolk and Suffolk were communicating a position more to east compared to the geograpical position they really where on that moment, ... and this is the " key " to realize what happened that night.

Bye Antonio

[Antonio Bonomi]

Hello everybody,

@ all,

I like to congratulate here this Royal Navy Officer : Commander John Warrand

Commander_Warrand_photo.jpg (89.84 KiB) Viewed 1383 times

Not only for this :

Tedd Briggs was one of only three men aboard to survive the tragedy (1,415 were confirmed lost). In both publications and recorded interviews, he refers to the sacrifice made by the squadron's navigating officer Commander John Warrand, who stood aside and allowed him to exit the compass platform first.

But also for having allowed David Mearns to find the Hood wreck since his personal performance was perfect being the BC1 squadron Staff Navigating Officer on board HMS Hood with ViceAdm Lancelot Holland.

In fact, after the all track run by Hood we can see above, his error margin was less than one sea mile.

Chapeaux Guys ... to this courageous, honorable and very competent Royal Navy Officer ...

This is when you realize what the " Royal Navy Highest Traditions " statement means.

Bye Antonio

[Alberto Virtuani]

Ciao, Alberto

[dunmunro]

The position of the wreck is not necessarily the position of the sinking.

Norfolk's estimate of the sinking position was made after the fact, well after the Hood had sunk and there was no way for Norfolk to know the exact position of the sinking.

[Antonio Bonomi]

Hello everybody,

@ Dunmunro,

you wrote :

The position of the wreck is not necessarily the position of the sinking.

Norfolk's estimate of the sinking position was made after the fact, well after the Hood had sunk and there was no way for Norfolk to know the exact position of the sinking.

I agree with you on both statements Duncan.

David Mearns on his book clearly explains that on page 187 with the box searching area and the drift of wreckage area, we are in any case on the range of a couple of sea miles.

In fact Norfolk provided an estimate position based on their own position and some evaluations they made looking at the Hood sinking area, just as David Mearns explains from page 107 to page 113 on his book.

The evident but absolutely NOT intentional error, does demonstrate that the Norfolk real geographical position on that moment was around 10-15 sea miles West compared to where they assumed to be based on their navigation calculations and transmitted 2 times, ... at 06.15 and 06.37, ... that was to the Eeast of the exact position David Mearns demonstrated being right.

Simple and very logic, ... mostly now well demonstrated.

Bye Antonio

[Antonio Bonomi]

Hello everybody,

@ All,

here the clean map with Hood and PoW correct tracks from 22.00 of May 23rd, 1941 until 05.43 of May 24th, 1941.

Map_trial_Hood-PoW_33.jpg (44.72 KiB) Viewed 1355 times

Are we all OK about it ?

Bye Antonio

[wadinga]

Hello All,

The fact that Holland was mislead into believing Lutjens was much further east was first really brought to public light in Graham Rhys-Jones excellent book https://www.amazon.co.uk/Loss-Bismarck- ... 1557505330 IMHO the best book on the subject by far in recent years. It had been mentioned before but not given any prominence. Those who have pilloried Holland unjustly have failed to take this into account.

It is a nice thing to praise Hood's navigator, but it would be unfair to denigrate the professionalism of, say Suffolk's navigator, David Howse. Hood's very size and fine lines may have meant she was thrown off her desired course less than the slab-sided Counties were.

One should be careful with a phrase like

Suffolk error growing thru the time, reaching the range of 20 to 30 sea miles, ... an entire meridian to meridian distance up there.

unless one points out that the German squadron's position is 90 miles out Yes ninety whole miles. Does that reflect badly on German equipment and skill/competence? No, not necessarily. I have been reading Jack Broome's "Convoy is to Scatter" where PQ17 and the cruiser escorts had a 20 mile navigational bust. It references an RN expert called to explain details at the court case brought by Broome for libel. The navigational expert who pointed out that not only magnetic compasses are inaccurate in high latitudes because of field dip, but even the gyro compass is less reliable because the earth's rotation is different to conditions further south.

Which ships passed north of Iceland in much higher latitudes? Which ships had the bigger navigational error? Which ships passed south in lower latitudes? Exactly

Duncan observed

well after the Hood had sunk and there was no way for Norfolk to know the exact position of the sinking.

This absolutely right, since Norfolk was so far to the NE it took a long time to get nearby for a sight on oil patch and debris.

All the best

wadinga

[Antonio Bonomi]

Hello everybody,

@ Wadinga,

I agree on all you wrote above. No one is denigrating anybody.
I was just pointing out someone evident credits allowing David Mearns finding the Hood mainly because of his precision.

I agree that the Germans even made bigger errors compared to Suffolk and Norfolk.
Everybody navigating and plotting on board Suffolk and Norfolk was just trying to do his best. No doubts for me.

However, this does not change my point, the 2 County class heavy cruisers were more to West compared to what they have been communicating all the way thru ... and their errors were increasing as time was passing, ... hour after hour.

Do you agree about this simple concept and statement ?

You wrote :

It had been mentioned before but not given any prominence. Those who have pilloried Holland unjustly have failed to take this into account.

You know that soon they will all need to change their mind about it.
They have been incorrect for 75 years and now the correct prominence will be provided.

Bye Antonio

[Antonio Bonomi]

Hello everybody,

@ All,

I think it is time to reveal the truth about what really happened that night.

Here it is. First you have to read very carefully the Suffolk and Norfolk radio messages I show you using the Admiralty Operation summary format that Dunmunro nicely showed us several times.

Read the Suffolk 00.09, the Norfolk 00.17 and the Suffolk again at 00.28.

Suffolk_Norfolk_radio msgs_early_24_May_1941.jpg (83.45 KiB) Viewed 1295 times

Plot them following my example on the map here below yourself, and after ... just ask yourself if ViceAdm Holland did the right approaching manoeuvre, ... obviously evaluating carefully the 3 radio communication inputs above mentioned that he received.

Holland_decision_inputs_03.jpg (44.39 KiB) Viewed 1295 times

@ Wadinga,

do you think there is enough " preminence " doing it in this way Sean ?

ViceAdm Lancelot Holland fully deserve it now, ... after 75 years ...

Please allow me here to highlight once again the " Royal Navy Highest Traditions " as it shows clearly.

Bye Antonio

[paulcadogan]

WOW!!

Antonio, that is simply brilliant! The turn to the north was no mistake, it was a keenly calculated move to ensure interception based on the cruisers' position reports - which later turned out to be too far east due to DR error.

If the cruisers' position reports had not been wrong, Holland would very likely have intercepted the Germans on that course.

Then when there was no sign of the enemy, he swung back to what should have been a parallel course.....

What about the position when Suffolk regained contact at 0247??

BTW - As of 5 PM EDT, Hurricane Matthew is still crawling along northwards at 7 mph, still SE of Kingston. We are having rain but no wind yet. Winds not expected to exceed 45 - 50 mph in eastern Jamaica.

[Antonio Bonomi]

Hello everybody,

@ Paul Cadogan,

many thanks for your nice compliments, ... ViceAdm L. Holland fully deserve all my efforts on revealing the truth now.

I think now everybody understands a bit better my post closing signature and why I choose it.

You got perfectly what happened ... ... as it is clear to be understood showing it this way.

Just the way it really happened.

Here what you asked for 02.56 :

Suffolk_msg_0256.jpg (25.71 KiB) Viewed 1269 times

and how it shows on the map, confirming Suffolk incorrect geographical position reports ( absolutely NOT intentional ) :

Holland_decision_inputs_04.jpg (46.09 KiB) Viewed 1269 times

Now it is obvious that at a certain point ViceAdm Holland understood that something was not right, ... and I can only correlate it to the fact that they got Suffolk and Norfolk radio messages with RD/F bearings and understood clearly that the positions they were both reporting was incorrect as they where BOTH to the West of their reported position, ... and at that point, ... all happened was clear for ViceAdm Holland.

That is the reason why he turned to South West at 02.03, just as you correctly understood too.

No errors made by ViceAdm Holland.
Somebody else made NO Intentional mistakes, ... but they did it, ... NOT ViceAdm L. Holland

Bye Antonio

[Cag]

Hi All,

Excellent work Antonio!

It does seem to get lost in the story of the loss of Hood the fact that Holland did, with often accepted and understandable errors in positional reports, get his ships into a position to engage Bismarck and Prinz Eugen which does deserve recognition.

I do have both the Suffolk and Norfolk May ships logs if you require anything please let me know.

Glad to hear that Mathew is passing by without too much damage I hope, take care Mr Cadogan!

As always best wishes
Cag

[paulcadogan]

Thanks Antonio...that is the position I estimated just viewing the chart on the screen.

So my next question would have been, why did Holland not adjust his course based on that position....BUT I quickly realized that he would have deduced that the position was wrong. Why? He had wisely sent his destroyers to spread out and search that area - and they had not reported anything.

So he was then able to deduce that the correct position was further east and made his course adjustments accordingly, knowing that at some point his course and that of the Germans would intersect - hopefully at a point where he would sight them.

He got it right...

To Cag: Thanks! Here in Jamaica, we are getting off relatively easy - in the hills above Kingston where I live, just intermittent rain yesterday and now just light winds. The hurricane is, however going to directly hit the extreme south western tip of Haiti. Maximum sustained winds are at 145 mph as of 5 AM EDT.