Question about bomb fusing

[Angus]

Hello , i read the flight manual but i have not found any info on this . We can choose the Nose or Noseand Tail or Tail fuse . What effect gives this setting ??

 

I guess the nose setting detonated the bomb at the impact ( on ground or target ) .

The Tail make explode the bomb in the air ( Near the ground ) . but i don't see for Nose/Tail ....

 

I'm right or wrong ???

[SUI - Mustang]

I would imagine that tail fusing is for a bit of a delayed explosion to get a bit of penetration. Maybe good for tanks or bunkers. Maybe Tail + Nose is just for more reliability?

[Art-J]

^ Mustang is right, although I don't think DCS models penetration vs fusing that precisely (if at all).

[IvanK]

This is typical of MK80 series bombs utilizing mechanical fuses like the M904/M905:

 

Tail fusing simply refers to Arming the Tail fuse solenoid in the rack such that when the bomb is released the wire that connects the rack and the tail fuse is held by the rack. This then extracts the safe arming wire from the fuse. The fuse is then free to start its arming process.

The same process occurs with nose fusing. Dual fusing is used to increase reliability in case a fuse fails.Tail fusing has nothing to do with penetration or detonation delay.

 

 

WRT penetration etc this is preset generally by fixed components in the fuse train called Detonation Delay units (DDU's) these typically come in various delays. Depending on the type of target/penetration required a specific DDU is selected and fitted during the bombing up process.

 

So on dropping the fuse goes through its arming process. Once armed the fuse train is ready to go bang. On impact the impulse goes through the DDU where it gets delayed by the DDU delay then to the explosive for the detonation.

 

When a bomb is dropped SAFE or jettisoned the rack fuse arming solenoids are not powered so the fuse arming wires are not held. As the bomb drops the fuse arming wires leave with the bomb. Since the wires are with the bomb the fuse cannot arm and the bomb "should" not detonate on impact.

 

In the case of MK82SE then typically the Fusing is performed by an inertia operated fuse like the FMU54. These fuses require the deceleration of the bomb caused by the drag petals opening to arm the fuse. Again a DDU can be used to delay the detonation post impact. the Drag petals are also held closed by a wire and retaining band again going routed through the Tail fuse arming solenoid on the rack. So if jettisoned the Drag petal wire and retaining pin go with the bomb ... the petals cant open so the fuse wont arm. In DCS this currently bugged as when you jettison MK82SE the fins still open ... they shouldn't.

Edited July 29, 2016 by IvanK

[SUI - Mustang]

The same process occurs with nose fusing. Dual fusing is used to increase reliability in case a fuse fails.Tail fusing has nothing to do with penetration or detonation delay.

 

Interesting! Why would you want to choose only one fuse then? Can you have different DDU's on the nose and tail fuse, giving you the option to choose between the two delay settings on the go? If not, why not have both fuses armed always to have better reliability?

[trippylummox]

In real life, you can have different types of fusing on the same bomb. Being able to choose nose/nose tail/tail affords the pilot a choice as to how the weapon will be employed. Does he need an air burst or penetration detonation. In the case of the same type of fuse used in both nose and tail it's more of a reliability decision. We wouldn't want insurgents to dig up a 500 to 2000 pound IED...

[mvsgas]

There are so many option on bomb fuzing in RL, it depends on many factors. Some bombs may carry two fuses, some may carry one. Some weapons, the fuzing wire is on the arming solenoids, some are wired to the pylon. Depends on the bomb, the fuzes used the aircraft and the desired effect.

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Edited July 30, 2016 by mvsgas

[Angus]

Thank you for these explanations :thumbup:

[ESAc_matador]

There are different behaviours... For Penetration usually tail fuzes are used, preventing them to be damaged while penetrating. But, also, you can configure one for instant detonation and the second for delay detonation. Pilot chooses the type of target, and select which to use. Or use both to ensure explosion.

 

Example. Dropping a bomb in a hangar.... better to delay the explosion till the bomb goes through the roof. Same in jungles.

 

Things like that. I don't think is modelled in dcs.

[autogyro]

Be aware there is a fuse arming table in the Dash 34 manual regarding nose/tail fusing.

 

From what I recall setting the wrong fuse setting (tail on a low drag Mk82) will make the bomb a dud.

 

I'll have to see if I can find it again.

[mvsgas]

Some examples

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