How popular were bomb delays

[InProgress]

In movies we always see instant explosions, while it's known that some targets are better to be hit with few second delays, like ships or buildings for better effect. Clod taught me that most bombs were delayed. Shallow bombing gives you automatically x seconds of delaye, same goes for other options of attack you choose. In box you can choose it as you wish.

 

But how about real life, was it popular? Used often, all the time or not very much? 

While I assume huge bombing runs over cities had delay because it's better to have bomb explode inside building than on its roof. But how about typical ground attacks on static or moving objects like bridges, tanks, trains, bunkiers. By the logic I would choose no delay while attacking moving objects since they can't run from it. While stuff like bridge I would bomb with big delay for more accurate (low) approach. How was this in real life?

[THERION]

As far as I know during the bombing raids over Germany the British bombers did bomb delays.

They had even fuses with chemical reaction so that the bombs would go off after hours and

eventually days.

 

Today's bomb disposal squads in Germany still find some US and British bombs with armed

fuses that didn't go off because the chemical reaction was disturbed (wet and soft ground).

[-SF-Disarray]

It varied by target and bomb application, as you would expect. The bombs the Japanese used to attack ships often had a delay, sometimes they were just modified battleship artillery shells like at Pearl Harbor. The effect being the bomb would detonate inside the ship, bypassing the armor, often to devastating effect. The Germans made extensive use of delay fuses in their terror bombing campaigns, sometimes referred to as 'morale bombing' in Spain and England. They would set some bombs to explode on or shortly after impact while others were set to go off minutes or hours after impact. This was done for various reasons but mostly to have a demoralizing effect on the bombed populous but also in an attempt to develop fire storms. The Germans got very good at the latter, and the former was found to be ineffective as the impersonal nature of bombing and being bombed didn't work on human psychology the way military theorists thought it would though they did have an effect on clean up and casualty recovery efforts. I imagine the US and British bombing campaigns used delay fuses for similar effect.

Edited May 2, 2018 by Disarray

[InProgress]

Interesting... how about active battles? They could not use hours and day delay since targets had to be destroyed immediately  but was some short delay used or on contact? And why this and not another?

[Aap]

2 minutes ago, EAF_T_Therion said:

As far as I know during the bombing raids over Germany the British bombers did bomb delays.

They had even fuses with chemical reaction so that the bombs would go off after hours and

eventually days.

 

Indeed. These bombs generally had secondary fuses that went off, when somebody tried to disarm the bombs. It causes a lot more headache, if a target like a runway or a factory was bombed with such bombs, as it could shut down the area for a couple of days, as the bombs could explode any time - or kill sappers that were trying to disarm then. So, depending on target and purpose, there were instant fuses and delay fuses to up to three days of delay. There were also fuses that activated certain time after release, intended to make bombs explode in the air instead of after impact.

[Sharpe43]

6 minutes ago, InProgress said:

Interesting... how about active battles? They could not use hours and day delay since targets had to be destroyed immediately  but was some short delay used or on contact? And why this and not another?

Usually a bomb fuse in an active engagement would be set for a number of seconds allowing an aircraft to get clear of the blastzone.

[InProgress]

But you don't need to be in any blast zone. No one says you have to drop it 10m from the ground.

[Aap]

16 minutes ago, InProgress said:

But you don't need to be in any blast zone. No one says you have to drop it 10m from the ground.

 

No one says that you cannot drop from 10m either, if needed. So, there were fuses for various bombing methods, targets and purposes, designed to explode before impact, at impact, with short delay or long delay.

[InProgress]

Yea but I mean what was usual way? Did they drop it with delay or on contact. Lets say it's enemy land, there could be aaa guns so it's not safe to fly low, they drop them from 500+ meters. Just to bomb usual ground mixed stuff, trucks, vehicles, tents, supplies etc.

[7.GShAP/Silas]

10 minutes ago, InProgress said:

Yea but I mean what was usual way? Did they drop it with delay or on contact. Lets say it's enemy land, there could be aaa guns so it's not safe to fly low, they drop them from 500+ meters. Just to bomb usual ground mixed stuff, trucks, vehicles, tents, supplies etc.

 

 

Why do you think it is not safe to fly low in enemy land?  Flying at the height of tree-tops is often the safest and smartest thing to do which is why it was and is done.

 

Do you mean Ju-87s divebombing?  That's a particular type of operation that comes with it's own variety of risks and vulnerabilities.  I've heard stuka pilots say they would release at ~400m, and I've seen footage with stukas dropping bombs from a more gentle dive at ~150m.

Edited May 2, 2018 by 7.GShAP/Silas

[InProgress]

Because is WoL you will never get hit by random aaa gun because there are not any. But if you fly on server that has random aaa guns all over map and you never know where, you will get shot down easly. It's not a challenge to hit low flying aircraft with a nice medium caliber gun.

[Royal_Flight]

1 hour ago, EAF_T_Therion said:

As far as I know during the bombing raids over Germany the British bombers did bomb delays.

They had even fuses with chemical reaction so that the bombs would go off after hours and

eventually days.

 

Today's bomb disposal squads in Germany still find some US and British bombs with armed

fuses that didn't go off because the chemical reaction was disturbed (wet and soft ground).

 

The Germans used to drop naval mines by parachute with a delayed fuse, with the idea that they would go off before hitting the ground which would wreck buildings with the lateral blast. 

 

The British experimented with mines as well and ultimately ended up developing 4,000lb ‘blockbusters’ for the same purpose. 

The average night bomber loadout was one of these plus several bundles of incendiaries, to knock buildings over and then set them on fire. 

[7.GShAP/Silas]

38 minutes ago, InProgress said:

Because is WoL you will never get hit by random aaa gun because there are not any. But if you fly on server that has random aaa guns all over map and you never know where, you will get shot down easly. It's not a challenge to hit low flying aircraft with a nice medium caliber gun.

 

 

Again, in the war and online flying low enough to mow the grass will keep you alive far longer than flying at an intermediate altitude like 1-2k when you're worried about AAA and enemy fighters.  If you're in a stuka and really want to be safe, you should be at ~4k anyway.  Every time I see someone fly an IL-2 or stuka at 200m-1k altitude I laugh.

 

In BoX, with the VVS you need to set your bombs to a 5 second fuse to ensure detonation at very low altitude, otherwise your bombs will often fail to explode.  I can only assume it's historical, but I've never seen reference to it in what I've read. 

Edited May 2, 2018 by 7.GShAP/Silas

[busdriver]

3 hours ago, InProgress said:

But you don't need to be in any blast zone. No one says you have to drop it 10m from the ground.

 

There is the obvious reason for fuze arm delay...to penetrate the ground/shell/structure/armor to get to a more vulnerable part of a target. The delay also has a psychological aspect on troops coming out of bunkers/shelters/fox holes/ditches/craters.

 

Just as an example, not the actual numbers but a reasonable estimate, think of the frag pattern of a 500kg general purpose bomb as having radius of a little over 600 meters. Airplanes dropping from low altitude or in a steep angle face the real hazard of becoming a "frag mort." There are three basic techniques to avoid becoming a frag mort.

1) Fuze arm delay

2) Minimum altitude for weapon release

3) Minimum lateral separation from the other bombers' target/point of impact

 

Number 1 works for the pilot WRT to his own bombs, part of this calculus includes things like having sufficient time of fall for a mechanical fuze to arm. If the bomb doesn't have enough time of fall the fuze doesn't arm, and the bomb is a dud (so number 2 is a factor for you). Other factors to consider are the altitude and airspeed at release. Up to this point, every bomb in the sim is a low drag general purpose weapon. Meaning you need more speed to exit the frag blast the lower you drop unless you have added a delay.

 

If you are a wingman on a low altitude attack then number 2 and 3 are extra considerations in dealing with your leader's bombs and other flight members. Stay above 600 meters and you're probably safe...FWIW there is no established extra margin of error for secondary explosions.

Edited May 2, 2018 by busdriver

[Talisman]

2nd TAF low level fighter bomber strikes, like Crossbow sites with Mosquito for example, used a mix of 10-second and 30-second delay fused bombs.  Eight to ten aircraft flying in pairs, first armed with 30-second delay bombs and the remainder with 10-second delay bombs.

Source: Royal Air Force 1939 - 1945, Volume III, The Fight is Won, by Hillary St. G. Saunders, Her Majesty's Stationery Office 1954.  Price 13s. 6d.

 

Happy landings,

 

56RAF_Talisman