U-boat vs. aircraft

[sublynx]

I found this extremely detailed description of a aircraft vs. U-boat combat from August 1943. Having read it I realise that it is not at all unrealistic for a U-boat to have some chance of survival against aircraft even in a surface fight.

http://www.uboatarchive.net/U-615ASW-6Crockett.htm

For the interested U-boatarchive also has all the war diaries of U-615. The fourth and last one reconstructed by BdU.

[Benti]

that read gave me some chills.
Thank you for sharing, I didn't know that u-boats were able to put up such a fight against so many aircraft.
In game I only risk a battle with an aircraft if it's late in war and my sub is equipped with two Flakvierlings and the double 3,7cm heeresflak.

benti

[Sailor Steve]

Part of the problem is that an aircraft downed can be replaced by a dozen more. A U-boat with a hole in the pressure hull is nothing more than a slow torpedo boat.

Aircraft shot down by U-boats - around 120.
http://www.uboat.net/history/aircraft_losses.htm

U-boats sunk by aircraft - around 250.
http://www.uboat.net/allies/aircraft/forces.htm

[sharkbit]

Originally Posted by Sailor Steve

Part of the problem is that an aircraft downed can be replaced by a dozen more. A U-boat with a hole in the pressure hull is nothing more than a slow torpedo boat.

Aircraft shot down by U-boats - around 120.
http://www.uboat.net/history/aircraft_losses.htm

U-boats sunk by aircraft - around 250.
http://www.uboat.net/allies/aircraft/forces.htm

I just recently read on uboat.net, concerning the Fight Back Order issued to the U-boats for a time, that Air Marshal Sir John Slessor, head of Coastal Command, said he would gladly trade an aircraft and its crew for a sunk u-boat.

http://www.uboat.net/history/fight_back_order.htm

I've gotten a little bored with aircraft in SH3. Same routine-aircraft spotted, crash dive, run submerged for a while, surface, repeat as necessary.

I've never really been surprised by aircraft. Not saying it will never happen though late war.

So with all that in mind, I've been experimenting with some randomness. Now when I get the aircraft spotted message, I pause the game, roll two dice, modify the roll by year, night, and/or radar warning. The result times 10 is the number of seconds before I can crash dive. Un-pause and start a timer and wait. If I get a "We're under attack!", I immediately crash dive or fight back, depending on situation.

It can be a little disconcerting watching a B-24 Liberator bearing down on you and not being able to do anything while the clock is ticking.

I think it nicely simulates the possibility of a surprise attack out of the sun or clouds, a lookout daydreaming, or a slow dive.

I'm still experimenting with the times though to find a happy medium. 15 seconds is waaay too long, and 5 seconds seems too short but it feels like 10 seconds may be too long as well. I've been noticing that with fighter type aircraft, they're on you really quick and attacking and then I've seen Swordfish coming and the bridge crew can finish their morning coffee before they have to crash dive.

[Vince82]

simulates the possibility of a surprise attack out of the sun or clouds

@Sharkbit: Many don't understand, I think, that this is what actually happend a lot. And that is a big reason why planes where really feared by commanders.

I like that you use dice to simulate a more realistic outcome.

In game Metox and radar can be edited a using silent3ditor to make it less effective. Decreasing the Metox arc to say 270 for example. This simulates detecting less aircraft due to new secret 10cm radar which was introduced by the allies. I'm curious to know what you think of this.

[Zosimus]

I think the concern over airplanes is overdone. Sure, they can damage you and sink you, but you can fire back and win. Destroyers are much more dangerous. When was the last time an airplane dropped more than 100 depth charges on you? Or rammed you? Or kept you under so long you thought you'd never shake him off?

[Vince82]

When surprised by an aircraft it's almost always better go full speed, take evasive maneuvers and fight. After the initial attack dive.

I'm sure it's in the GWX manual.

[scott_c2911]

The only time i have been surprised by an aircraft or a small formation is when ive missed the radar signals detected warning and even then I just dive. The only time an aircraft has caused damage is from its guns and not its bombs and thats if i choose to give it some lead out of boredom more than anything. Destroyers have accounted for all of my ingame deaths and I regard them as my most dangerous foes. I have homing torps now though so I can have a crack back. Its April 1945 in my career so its not long now before its all over. This is my last patrol. Ive been at it for nearly 12 months and have been going since August 1939. That report was a cracking read Ive got to say and thanx to the op

[Foggy]

I have an Officer that has multiple skills (one being cannon, another being torpedo, the third I think is Helmsman). He is always posted in either the torp room (giving a large bonus there) or on the top of the conning tower during surface runs. When I get alerted that we've spotted enemy aircraft, I make sure that he's on the conning tower, then I use a Petty Officer that has the Flak skill and I put him on the flak gun. With both of them present, the skill bar is full for the flak gun, and I tell him to engage targets at medium or long range and let him have at it. The guy never seems to miss. He'll take out 4 planes and we'll keep on trucking without a scratch. Sometimes I have to turn the boat to make sure the flak gun can still aim at where the planes are coming from, but his accuracy is ridiculous lol. His accuracy probably isn't realistic, but he sure keeps us safe from the birds lol.

[U-15]

Originally Posted by Zosimus

I think the concern over airplanes is overdone. Sure, they can damage you and sink you, but you can fire back and win. Destroyers are much more dangerous. When was the last time an airplane dropped more than 100 depth charges on you? Or rammed you? Or kept you under so long you thought you'd never shake him off?

Zosimus,

http://www.uboat.net/boats/u570.htm

It's not a risk worth taking.
Stay deep, and hopefully stay safe.

I always tell my crew that if I wanted to shoot planes down I would have joined the Luftwaffe

[Vince82]

Recently posted by Armistead in the SH4 forum, same thing, they are also discussing air attacks:

depends on your mods, if playn stock you can survive a couple direct bomb hits, when in real life, that would be it for your sub. same with surface ships, one shell could easily be the end of your ship. a few mods give these results, so you don't mess with planes or gun battles with escorts on the surface....

[vanjast]

Read the book 'Conflict over the Bay' by Norman Franks, which covers RAF Coastal Commands hunt for Uboats during May-August 1943.
This is the critical time period where tactics on both sides were evolving wrt to UBoat-vs-Aircraft.

Essentially the Allies developed 'search blocks' in the Biscay Bay, where many aircraft would patrol. This area was wide enough so that a UBoat would not be able to cross it without surfacing to recharge batteries, thus a better chance of being detected by ASW - Aircraft as well as Hunter Killer groups.

Every one of Donitz's fight it out tactics brought only limited success and was quickly nullified by a change in allied tactics.

- If a single UBoat tried to fight on the surface, a single aircraft would attack. Invariably it meant a damaged or sunken UBoat. A damaged Uboat would have to return to port.
Allied aircraft usually carried only enough 'DCs' for one attack (sometimes they would use half their ordinance for a second attack to foil the Kaleun).
If the Uboat did not sink, if the aircraft wasn't badly damaged, it would circle the sub until other aircraft, hunter killer groups arrived, or had to leave for shortage of fuel.

- Eventually Donitz ordered 3 Uboat formations to transverse the search blocks on the surface.
What the allies did when discovering this, was to circle the sub group calling in more aircraft and HK groups. Up to five aircraft would be circling the 3 boats like vultures waiting to pounce.

Communication between aircraft, and between subs did not exist so neither in each group knew what the other was up to until they did something. Also keeping subs in formation while watching the vultures was a big problem and usually one sub went out of formation - the aircraft would nearly crash into each other descending on this unforunate sub.
With the ensuing chaos, the other subs would then try to submerge - very few got away unscathed.

If not enough a/c coulld be called in, a HK group could arrive within a few hours... and the Kaleuns definitely didn't want this. Some subs got away only to be hammered by HK groups that were guided in by the aircraft.

I'm not sure whether SH3 takes all these factors into account but one can confidently say that you should crash dive.. even for a seagull

[Zosimus]

Originally Posted by U-15

Zosimus,

http://www.uboat.net/boats/u570.htm

It's not a risk worth taking.
Stay deep, and hopefully stay safe.

I always tell my crew that if I wanted to shoot planes down I would have joined the Luftwaffe

WTF?

http://www.defensemedianetwork.com/s...ipher-machine/

"On the morning of Aug. 27, 1941, U-570, under the command of Kapitänleutnant Hans-Joachim Rahmlow, surfaced off the coast of Iceland and was immediately spotted by a British Hudson bomber on anti-submarine patrol. As the Hudson dove to attack, Rahmlow ordered a crash dive..."

As we said before, don't crash dive. Fire back, wait till the attack passes, and then dive.

"... but before U-570 could escape, it was bracketed with four depth charges. The U-boat suffered only minor damage, but the inexperienced crew, many suffering acutely from seasickness, panicked."

Second mistake. Don't panic. The boat was barely scratched.

"Rahmlow himself was new to U-boats and U-570 was his first operational command. U-570 surfaced and crew members unfurled a white sheet. Rahmlow, meanwhile, sent out a radio message to U-boat command stating what happened and that he had surrendered."

Don't surrender. What's the point?

[Zosimus]

My Most Dangerous Moment with Aircraft

I had been creeping up on a convoy in poor weather when I got pinged. I immediately went to 179 meters depth, but with three escorts circling me one of them always seemed to get in a lucky ping. Finally, after almost 3 hours, I shook them off.

The convoy was long gone, but I surfaced in 9 km (moderate) visibility and began following the escorts as they headed (medium speed) back towards the convoy. After two hours I had kind of located the convoy. I knew that it was somewhere to the southeast of me because I saw an escort come from that direction doing its little search dance. Meanwhile the three escorts were SSW of me as I was threading the needle trying to get close enough to the convoy to see a cargo ship and determine the exact course so I could go out and around to take it on.

It was at that moment that a fighter aircraft showed up heading towards me from south by south east. Obviously, as you know, the real danger was not the aircraft. The problem was all four escorts immediately made a beeline for my position.

I did not crash dive. We manned the flak gun and we fired at the onrushing plane as it strafed us. It didn't hit us, and we didn't hit it. As soon as it passed we crash dived. After another hour in the depths of the ocean they gave up on us and I surfaced to find it raining heavily.

I gave up on the convoy and went in search of better weather.

[U-15]

@15#

http://www.uboatarchive.net/U-570/U-570INT.htm

V. CAPTURE OF "U 570"

"At approximately 0830 on the morning of 27th August, 1941, "U 570" submerged in position about 62° 15' N. and 18° 35' W. to obtain some respite from heavy seas which had already caused much seasickness among her inexperienced crew. At 1050 the captain decided to surface again and brought the U-Boat up from a depth of approximately 90 ft. What happened next can only be attributed to the lack of training of the Commander. Rahmlow entirely forgot to make any observation for hostile aircraft before exposing his ship. It so happened that a Hudson aircraft "S" belonging to 269 Squadron, and piloted by Squadron-Leader Thompson, was almost immediately overhead. "U 570" perceived her danger too late and, while she was attempting to crash dive, the aircraft dropped a stick of four 250 lb. depth charges, at an angle of 30° to the U-Boat's track. These exploded close to her, the nearest being about 10 yards away. One minute after the water disturbance had subsided "U 570" surfaced again, bow down, and 10 to 12 of her crew came on deck. The aircraft attacked with guns until a white flag was waved from the conning tower. It was established by interrogation of prisoners that, at the moment of the attack, confusion reigned within the U-Boat. The detonation of the depth charges, the smashing of instruments, the formation of gas, thought by the crew to be chlorine gas, and the entry of a certain amount of water apparently convinced Rahmlow that his boat was lost, for her ordered the crew to don life-jackets and mount the conning tower."

Zosimus, if you have an elite crew and an experienced commander, I accept you may have a fighting chance in a one on one with an aircraft; but only if you are forced to fight it out, because you can't submerge in time.

However, as we both know, Rahmlow was inexperienced, this being his 1st war patrol and out of a compliment of 43, only 4 had completed a war patrol.
As you can see from the quoted text, after the initial mistake of surfacing before checking for aircraft, the situation became compounded by panic and inexperience amongst crew and officers.
The article goes on to say that the seas made it impossible to man the guns, so a fight was out of the question even if the crew had the will to do so.

1st mistake: Surfacing in broad daylight; irrespective that there are upset tummies all over the boat.
This mistake compounded by not carrying out proper air surveillance.

2nd mistake: Resurfacing after being attacked.
The Engineering Officer was one of the 4 that had patrol experience.
Rahmlow should have dived as deep as possible and used his EO's knowledge to assess the situation.
Repair the damage and carry on, or surface and surrender.

As I haven't being in a situation that has required me to make instant life determining decisions, I am certainly not going to criticize somebody for making the wrong mistakes in a real life situation.

From a strategic point of view this is a U-boat that was lost from its main purpose, i.e. the sinking of enemy merchant vessels.
This purpose requires the U-boat to be undetected to maximise its chances of success.
Something, that brawling it out on the surface with aircraft is not going to enhance those chances.

Ok, call me unadventurous if you like, I can take it.