Questions about late war aircraft patrols/GWX

[silentwayIII]

I'm in April of 44' about 500k north of Scapa Flow. Throughout this patrol, the frequency of my submarine being detected by aircraft, while surfaced is very high. Sometimes, the number of aircraft are as many as six that head towards me when they make radar contact with my boat.

Is this realistic or not? I would think two aircraft together is a push, but six seems unrealistic. The quantiy of aircraft patrolling the English Isles would have had to be in the many hundreds (my guess) if what I'm encountering is an example of the coverage.

Because of the frequency of the patrols, the amount of time I have on the surface...to recharge batteries, compressor and air is almost always too little to get the job done unless the weather is too severe for patrol aircraft to fly in.

While the snorkle is great, unless we are in late 44' there is no way to detect aircraft above you until, many times, its too late.

German submarine activity in and around the British Isles continued until the end of the war although not very successfully. The majority of the boats sent on these patrols were standard boats with some upgrades, nothing special. Many survived these patrols.

So...is the numbr of aircraft and the frequency of contact amped up a bit or not?

silentwayIII

[melnibonian]

Historically speaking the allies had saturated the air in the areas where U-Boats were operating. From 1944 onwards there were cases where U-Boats travelled submerged and had no time to recharge the batteries (due to allied air cover). In the Iron Coffins the trip from France to Norway of the VIIC of H. Werner was totally submerged. I think GWX models the allied air cover very well. The idea is that there are far too many planes and if you stay on the surface you die. If you dive you might die, and in general if you manage to survive the war you're a lucky s*&%$ of a b*&^*%. Exactly as in reality.

[Jimbuna]

Don't disagree with a word mel says :nope:

Allied air coverage is depicted as historically accurate as research allows (believe me, there has been a huge amount of effort put in). :yep:

Just thinking out loud here, but is it possible you are running at TC and are getting the impression that contacts are too frequent :hmm:

I have fallen into that mistaken belief in the past whilst testing air cover :oops:

[melnibonian]

On a further note to add to Jim's post, the old joke between the Panzer Divisions soldiers (they were prime targets) during the Summer of 1944 in France concerning the air cover was: "If you see a white wing on the sky it's the USAAF, if you see a black wing it's the RAF and if you see no wings it's the Luftwaffe" (Slightly paraphrased but the meaning is the same) :yep:

[silentwayIII]

Thanks for the quick replies. This being the case, the only way to traverse these open areas was to use the snorkle. How easy/hard was it for an aircraft to make contact with a submarine because its snorkle was a meter or two above the water.

I remember reading at some point in time that the radar footprint of the snorkle was left too large by the devs. Has this been changed in GWX or not?

silentwayIII

[melnibonian]

Thanks for the quick replies. This being the case, the only way to traverse these open areas was to use the snorkle. How easy/hard was it for an aircraft to make contact with a submarine because its snorkle was a meter or two above the water.

In reality the U-Boats were not using the snort all the time. They usually travel submerged on batteries and used the shnorkel for 2-3 hours every day to recharge the batteries and ventilate the boat (some times they were surfacing for an hour or two as well). Basically the shnorkel allowed the boats to be invisible to planes (as they were under water "all" the time), but if a DD was in the vicinity things were difficult. Because of that U-Boats were not travelling more than 20-30 miles per day.

[Jimbuna]

The schnorkel was detectable to radar, especially with the advent of the 3cm then the 10cm radar (or vice versa) page 347:

http://books.google.com/books?id=wpFMWeLmp4cC&pg=PA347&lpg=PA347&dq=radar+schnorkel&source=web&ots=foE4UUbzYk&sig=D57WUBYsgCGxQ8-hSHwo6-d_vxM

Remember, periscopes were also detectable, and they were much smaller in cross section.

[Safe-Keeper]

The Radar Warning Receiver is your best friend. I always buy it first thing when embarking on late-war campaigns. I can't begin to count how many times it's saved my hide:up:.

[Penelope_Grey]

Radar warning is a good buddy, especially if you are driving something that doesn't dive on a whim.:up:

[TarJak]

If you run a Type IX then on the occasions when you do get to the surface run with decks awash so your diving time is reduced. It slows you down on the surface but does make for a quicker dive.

Another trick I use is to leave the schnorkel up when running surfaced which will give you a few extra seconds on flank speed with the diesels as you dive. Probably not totally realistic but allowable in the game and I'd rather keep diving at 10-12kt until my tail is underwater than get blown up!

[Kpt. Lehmann]

Notes:

1) If you are sailing late war patrols, be sure to read up on how to use the "Late War Sensors" optional mod that is INCLUDED with GWX. (You can find a full description in the GWX manual.)

2) Was the over-large radar cross section of the snorkel head reduced by GWX... Yes it has been reduced... though it still detectable by enemy radar, albeit with lesser effectiveness.

[Cezbor]

Another trick I use is to leave the schnorkel up when running surfaced which will give you a few extra seconds on flank speed with the diesels as you dive.

This trick is very usefull when you're under attack peformed by fast fighter-bomber planes (f.e. Mosquitoes). It's one of my most prefered tactics for type IX boat. It saves you an extra 3-5 seconds. In many cases those extra seconds decide about your fate:yep: .

[Kpt. Lehmann]

For anyone wishing to play in a realistic way when using the schnorkel, do not exceed 5 knots speed when submerged.

In RL, submerged speeds any higher than 5 knots would cause tremendous vibrations followed by structural failure and loss of the schnorkel itself. (When the schnorkel is deployed.)

[dize]

The schnorkel was detectable to radar, especially with the advent of the 3cm then the 10cm radar (or vice versa) page 347:

http://books.google.com/books?id=wpFMWeLmp4cC&pg=PA347&lpg=PA347&dq=radar+schnorkel&source=web&ots=foE4UUbzYk&sig=D57WUBYsgCGxQ8-hSHwo6-d_vxM

Remember, periscopes were also detectable, and they were much smaller in cross section.

i think this is debatable. in reality the increased usage of the snorkel presented the allies with a noticeable problem. alled cvl hunter killer groups in the atlantic got dissolved in late 44, coz the snorkeling uboats where impossible to find, with the usual means of radar patrol planes/dd's.
i think the article on british radar technics in uboat.net is very enlightening...

But in October 1944, the Allied became aware of two worrying developments: The appearance of a new class of U-boats, and the fitting of the "Schnorkel (http://www.uboat.net/technical/schnorchel.htm)" to U-boats. The latter was virtually undetectable by 10cm ASV radar. In a meeting on 22 November, it was decided that developments of the 3cm ASV radar offered the best hopes, although experiments with 1.25cm radars were also conducted. The work was undertaken both in Britain, under the aegis of B.J. O'Kane, and in the USA, where the US Navy started the aptly called "Project Hawkeye" in the Radiation Laboratory of the MIT. However, the tests were not concluded before the end of the war.

imho, the ability to detect the snorkel or even the periscope on a rather regular basis, is a bit of a myth. remember that asw aircraft where always on the bottom of the priority list, when it came to getting the latest radar stuff.

[Jimbuna]

The schnorkel was detectable to radar, especially with the advent of the 3cm then the 10cm radar (or vice versa) page 347:

http://books.google.com/books?id=wpFMWeLmp4cC&pg=PA347&lpg=PA347&dq=radar+schnorkel&source=web&ots=foE4UUbzYk&sig=D57WUBYsgCGxQ8-hSHwo6-d_vxM

Remember, periscopes were also detectable, and they were much smaller in cross section.

i think this is debatable. in reality the increased usage of the snorkel presented the allies with a noticeable problem. alled cvl hunter killer groups in the atlantic got dissolved in late 44, coz the snorkeling uboats where impossible to find, with the usual means of radar patrol planes/dd's.
i think the article on british radar technics in uboat.net is very enlightening...

But in October 1944, the Allied became aware of two worrying developments: The appearance of a new class of U-boats, and the fitting of the "Schnorkel (http://www.uboat.net/technical/schnorchel.htm)" to U-boats. The latter was virtually undetectable by 10cm ASV radar. In a meeting on 22 November, it was decided that developments of the 3cm ASV radar offered the best hopes, although experiments with 1.25cm radars were also conducted. The work was undertaken both in Britain, under the aegis of B.J. O'Kane, and in the USA, where the US Navy started the aptly called "Project Hawkeye" in the Radiation Laboratory of the MIT. However, the tests were not concluded before the end of the war.

imho, the ability to detect the snorkel or even the periscope on a rather regular basis, is a bit of a myth. remember that asw aircraft where always on the bottom of the priority list, when it came to getting the latest radar stuff.

Your correct when you use the word 'debatable'. However, the article you quote clear does not state or use the term 'was not' but merely 'virtually', which infers that it was detectable some of the time.
I have seen reports on the internet where pilots (late in the war) have reported faint signals which upon further investigation have led them to U-boats lying just beneath the surface.
I'm at college right now, but I hope someone can post a link to one of those web pages. I will attempt to in a few days or so after my exams :up:

[Pablo]

Your correct when you use the word 'debatable'. However, the article you quote clear does not state or use the term 'was not' but merely 'virtually', which infers that it was detectable some of the time.
I have seen reports on the internet where pilots (late in the war) have reported faint signals which upon further investigation have led them to U-boats lying just beneath the surface.
I'm at college right now, but I hope someone can post a link to one of those web pages. I will attempt to in a few days or so after my exams :up: Hi!

Not a web page, but:

The schnorchel failed for several reasons: it slowed the boat to a mere five or six knots, stretching transit times to a point where a patrol would last only a few days; the vibrations made it very difficult to operate the periscopes effectively; the device often failed or filled with water causing serious problems for the crew; the schnorchel could be observed by 3-cm radar despite German efforts to provide stealth capabilities. Blair, Clay, Hitler's U-Boat War: Part 2 p. 709

[Jimbuna]

Cheers Pablo :up: ....you took me direct to the page (it goes on to discuss the structural faults with the type XXI) :know: