USN Thermal Protection on Bombs (green vs. gray)

[Nealius]

TL;DR TImeline of Navy thermal protection on Mk80 series

1967 - Forrestal Fire

c.1972 ~ c.2001 - thermal coated bombs were green (two yellow bands)

c.2002 ~ c.2003 - gray color starts being introduced, but green bombs remain in service (two yellow bands on both)

c.2004 ~ present - gray color fully replaces green (two yellow bands, sometimes three yellow bands)

Long Version

Most of us Naval Aviation nerds know about the Forrestal Fire in 1967, which spurred the USN to research bomb cookoff times and develop a thermal coating for the Mk80 series bombs. However, there's a misconception that thermal protection and a gray color are mutually inclusive, and that all Navy bombs after 1967 should be gray. The color of the bomb body does not indicate thermal protection. The number of yellow bands on the nose of the bomb indicates whether it has thermal protection or not (US Navy Academy document; "Chapter 9 Aircraft Ordnance").

1 yellow band = no thermal protection

2 yellow bands = thermal protection

3 yellow bands = ???? (I have seen this on post-2004 images but cannot find a reference explaining the third band)

So what's the timeline? I cannot find a written resource, but a long search through images on seaforces.org will give a rough timeline for when to use green bombs or gray bombs.

1970; no thermal protection (note single yellow band)

1972; thermal protection begins service (note the inboard bombs have no thermal protection, while the outboard bombs do)

1978, 1982, 1991, 1997 respectively; thermally protected bombs in service are still green

2002~2003; the gray color is introduced with some aircraft loaded with all-green, others loaded all-gray, and others with mixed loads

2004 ~ present; gray seems fully integrated, sometimes seen with three yellow bands instead of two

In conclusion

If you're flying pre-1972, leave bombs default. 

If you're flying 1972-2002ish, use the green bomb textures: 

If you're flying post-2002, use the gray bomb textures (either the in-game ones or the various community mods on User Files):

And on that note, anyone know what three yellow bands means? 

 

 

 

 

 

[ngreenaway]

Maybe this source can help you on three bands?

Chapter 9: aircraft ordnance

 

I found this diagram in it:

Edited March 4, 2022 by ngreenaway

[Nealius]

Thanks! Same document I used to source the two yellow bands. I'm surprised they mentioned it in the figures and not in the text, but that explains why I couldn't find it using the search function.

Apparently BLU-110/111 is just a different explosive filler that is "thermally insensitive." I guess that makes them safer than the standard Mk80s that only have external thermal protection.

[ngreenaway]

Just needed a second set of eyes, I guess

 

I'm sure there's blu110/111 documentation that may discuss further 

[Frederf]

The three bands seems to be reserved simply to visually differentiate the BLU-111/110/117 warheads from their Mk-82/83/84 equivalents. As far as I can tell It can also be taken to mean the use of PBXN-109 instead of Comp H6 as all the USN BLU-100 series bombs have the more insensitive filler.

[Vapor_12]

This is correct, but not "also" so much as "does". Naval Bomb Live Units use PBXN, and MK series munitions use Tritonal. These are, as far as I am aware, a rule. Marks are always Tritonal and BLUs (including penetrators like 109 common in Air Force inventory) are PBXN. 

[Nealius]

@BIGNEWY @Flappie @NineLine Is the time period and availability of green ablative coating being considered for the upcoming fuse options and USN bomb options?

[BIGNEWY]

planned with the fuzes update, and shown in Wags latest video as an option. 

thanks

[Nealius]

13 minutes ago, BIGNEWY said:

planned with the fuzes update, and shown in Wags latest video as an option. 

My question may not have been clear. Will we get both USN gray and USN green with the option? Pre-2002 the USN bombs were green, not gray. Both coatings exist in the DCS file structure.

Wags' video only shows two options: USAF and USN, and makes no mention of what the USN selection will actually look like: gray, green, or dependent upon mission date.

Edited May 20 by Nealius

[Northstar98]

On 5/20/2024 at 11:46 AM, Nealius said:

My question may not have been clear. Will we get both USN gray and USN green with the option? Pre-2002 the USN bombs were green, not gray.

Both options (USN grey and green) already exist in the textures so I think it's a fair assumption that all 3 will come some way or another.

 

One thing I think I should bring up though is shouldn't the textures (i.e. thermally protected or not) be dependent on the bomb variant?

For instance, shouldn't the GBU-31(V)1/B and -31(V)3/B only have the USAF textures available? And the GBU-31(V)2/B and -31(V)4/B (which already exist in DCS) have the USN textures (probably both) available? The same is true for the GBU-38 (though only the AF (V)1 exists in DCS).

You can say the same for the GBU-24 in DCS - the A/B should have the USAF textures, the B/B should have the USN textures.

EDIT: As of DCS 2.9.5.55300 there is a seperate GBU-24A/B and B/B with the appropriate textures (though it would be nice to also get the green thermal coating as well as the grey)

Mk 80 series and Paveway II series are different, they don't have different designations depending on whether they're thermally protected or not, but they do have different warheads (filled with PBXN-109 as opposed to Tritonal) which would be the BLU-111A/B, BLU-110A/B and BLU-117A/B for the Mk 82 (and GBU-12, GBU-38(V)2/B), Mk 83 (and GBU-16, GBU-32(V)2/B) and Mk 84 (and the GBU-10 and GBU-31(V)2/B) respectively.

For all of this, all of the ground work already exists, it just involves copying and pasting some of the existing entries (as has already been done for the GBU-31 series) and having the textures appropriately set for each applicable variant.

Edited May 23 by Northstar98
Addendum post DCS 2.9.5.55300

[Nealius]

The snakeeye fins as well, now that you mention different bomb variants between the service branches. The 3D model has been in the file structure as long as the green and gray coatings have.

On an unrelated note, why is this thread in Customer Support and not in DCS World Topics?

[BIGNEWY]

4 minutes ago, Nealius said:

On an unrelated note, why is this thread in Customer Support and not in DCS World Topics?

moved to wish list