# Super Rapid Blooming Overhead Chaff **URL:** \ **Category:** Factual Questions\ **Created:** [June 13, 2021, 1:18pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169 "2021-06-13T13:18:41Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![cannonkuo](https://avatars.discourse-cdn.com/v4/letter/c/b9bd4f/32.png) [@cannonkuo](https://boards.straightdope.com/u/cannonkuo)\ **Post date:** [June 13, 2021, 1:18pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/1 "2021-06-13T13:18:41Z")
I read a memo from the Under Secretary of Defense for Policy (Iklé) to Secretary of Defense Weinberger dated 24 June 1982. It says: On June 10, 1982, the Navy released 6 **Super Rapid Blooming Overhead Chaff (SRBOC) launchers** and 1200 Rounds. We are now in receipt of a request for an additional 6 launchers and 1200 more rounds. Navy has indicated that this second request for **Hycor rounds** has a direct impact on Navy readiness. What are super Rapid Blooming Overhead Chaff (SRBOC) Launchers and Hycor rounds? Thank you. ---
**Author:** ![Si\_Amigo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/si_amigo/32/2877_2.png) [@Si\_Amigo](https://boards.straightdope.com/u/Si_Amigo)\ **Post date:** [June 13, 2021, 1:25pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/2 "2021-06-13T13:25:08Z")
Perhaps the specific term is old and we just now call it chaff or simply countermeasures . > **[Mark 36 SRBOC](https://en.m.wikipedia.org/wiki/Mark_36_SRBOC)** > > Pages for logged out editors learn more > > The BAE Systems Mark 36 Super Rapid Bloom Offboard Countermeasures Chaff and Decoy Launching System (abbreviated as SRBOC or "Super-arboc") is an American short-range decoy launching system (DLS) that launches radar or infrared decoys from naval vessels to foil incoming anti-ship missiles. The decoys present false signals and interference to the attacking missiles' guidance and fire-control systems. The Mark 36 SRBOC is similar to the Sea Gnat dec... ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 13, 2021, 5:19pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/3 "2021-06-13T17:19:47Z")
I would imagine that “super rapid blooming” chaff is something that turns from a single launched munition into a chaff cloud very quickly. “Bloom” seems like a reasonably descriptive verb for that process. In case we need to go back further than that, “chaff” is a cloud of fragments of usually-hot metal, intended to either foul the engines of aircraft flying through the cloud, or to act as a decoy for other weapons. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [June 13, 2021, 5:31pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/4 "2021-06-13T17:31:36Z")
“Super Rapid Blooming Overhead Chaff” sounds like the English translation of an anime/manga title. Possibly a slice of life story about a server in a ramen restaurant who aspires to be a calligrapher. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [June 14, 2021, 12:31am UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/5 "2021-06-14T00:31:54Z")
@Chronos nailed “blooming”. Named for the way a chaff cloud looked on an old fashioned analog radar screen. A small spot of light appears and rapidly grows in diameter and brightness then slowly fades over a time of minutes. Like the lifecycle of a flower: quick to appear from a tiny bud, then slow to fade. Here’s chaff: > **[Chaff (countermeasure)](https://en.wikipedia.org/wiki/Chaff_(countermeasure))** > > Pages for logged out editors learn more > > Chaff, originally called Window by the British and Düppel by the Second World War era German Luftwaffe (from the Berlin suburb where it was first developed), is a radar countermeasure in which aircraft or other targets spread a cloud of small, thin pieces of aluminium, metallized glass fibre or plastic, which either appears as a cluster of primary targets on radar screens or swamps the screen with multiple returns, in order to confuse and distract... On a ship you’re probably looking to defeat the homing radars of anti-ship missiles. In an airplane you’re looking to defeat the same sort of homing radars in anti-aircraft missiles, but also ground- or air-based tracking radars. In airplanes the high speed of the passing air helps the disperse the chaff cloud very quickly. Ships don’t have that, but need a larger cloud to protect a larger target. So their chaff rounds need to have something to assist in spreading a compact canister into a WAG hundred-plus foot diameter cloud of RF confusion. Presumably some sort of low explosive to create a dispersing cloud without destroying the flimsy chaff itself. As to the cool anime name, I’d bet that at one time the USN had “chaff launchers”. Then somebody improved those and suddenly they had “rapid blooming chaff launchers”. Then somebody improved _those_ and now (= 1982 when the memo was written) they have “super rapid blooming chaff launchers”. What’s next? “Incredibly awesomely super rapid blooming chaff launchers?” (pronounced “ **I** -Ass-r-bloockel”) of course. You heard it here first! 😉 It appears Hycor was the name of the defense contractor that built the original Mk36 system. Which was later subsumed into first United Defense and later BAE. The point of the memo was that by citing certain buzzwords from procurement legislation, USN was saying “We really _really_ need this right away, so shortcut the usual 5 year red tape procurement process and just place an additional order with the usual supplier for delivery ASAP.” ---
**Author:** ![Si\_Amigo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/si_amigo/32/2877_2.png) [@Si\_Amigo](https://boards.straightdope.com/u/Si_Amigo)\ **Post date:** [June 14, 2021, 12:48am UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/6 "2021-06-14T00:48:33Z")
So where would the Navy have deployed 6 SRBOC at in June 1982? The Persian Gulf? Off of Lebanon? ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [June 14, 2021, 12:58am UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/7 "2021-06-14T00:58:04Z")
> [@LSLGuy](#): > > It appears Hycor was the name of the defense contractor that built the original Mk36 system. But probably not this one (even though they have had the name since 1981.) > **[Hycor Biomedical History | HYTEC 288 Allergy System & NOVEOS](https://www.hycorbiomedical.com/timeline)** > > HYCOR Biomedical has been around since 1981. We provide a detailed timeline of our accomplishments through the years including our entry to allergy with the acquisition of Ventrex, the development of the HYTEC 288 Allergy System, the creation of the... ---
**Author:** ![cannonkuo](https://avatars.discourse-cdn.com/v4/letter/c/b9bd4f/32.png) [@cannonkuo](https://boards.straightdope.com/u/cannonkuo)\ **Post date:** [June 14, 2021, 12:56pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/8 "2021-06-14T12:56:10Z")
Thank you. ---
**Author:** ![cannonkuo](https://avatars.discourse-cdn.com/v4/letter/c/b9bd4f/32.png) [@cannonkuo](https://boards.straightdope.com/u/cannonkuo)\ **Post date:** [June 14, 2021, 12:57pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/9 "2021-06-14T12:57:09Z")
Thank you very much. ---
**Author:** ![Dissonance](https://avatars.discourse-cdn.com/v4/letter/d/85f322/32.png) [@Dissonance](https://boards.straightdope.com/u/Dissonance)\ **Post date:** [June 15, 2021, 1:40am UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/10 "2021-06-15T01:40:25Z")
> [@Si\_Amigo](#): > > So where would the Navy have deployed 6 SRBOC at in June 1982? The Persian Gulf? Off of Lebanon? I highly suspect that they were not deployed by the US Navy; note the language used in the memo. It says: “On June 10, 1982, the Navy **released** ” 6 Super-RBOC launchers and 1200 rounds. In military bureau-speak this terminology usually means they were given (not sold) to another party directly from US stockpiles. The date of the request, June 10, 1982, was near the end of the Falklands War, and the Royal Navy used the Super-RBOC extensively during the conflict. My guess is that the USN transferred 6 launchers and 1200 rounds to the Royal Navy to replace rounds they used countering/trying to counter Exocets, and was noting that the second request for an identical amount would impact the USN’s own readiness by depleting the USNs stockpile so heavily. ---
**Author:** ![Si\_Amigo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/si_amigo/32/2877_2.png) [@Si\_Amigo](https://boards.straightdope.com/u/Si_Amigo)\ **Post date:** [June 15, 2021, 2:00am UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/11 "2021-06-15T02:00:49Z")
That makes sense as I could not find any action around that specific time frame other than the Falklands. It would also make sense as to why the request went all the way to the Secretary of Defense. Did not recall that we helped British out that way. And yes, those Exocet missles were the news of the day back then. One took out a British destroyer , the HMS Sheffield IIRC. > **[HMS Sheffield (D80)](https://en.m.wikipedia.org/wiki/HMS_Sheffield_(D80))** > > Pages for logged out editors learn more > > > > Operation Corporate > HMS Sheffield was a Type 42 guided missile destroyer and the second Royal Navy ship to be named after the city of Sheffield in Yorkshire. Commissioned on 16 February 1975 the Sheffield was part of the Task Force 317 sent to the Falkland Islands during the Falklands War. She was struck and heavily damaged by an Exocet air-launched anti-ship missile from an Argentine Super Étendard aircraft on 4 May 1982 and foundered while u... ---
**Author:** ![MikeF](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@MikeF](https://boards.straightdope.com/u/MikeF)\ **Post date:** [June 15, 2021, 4:07pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/12 "2021-06-15T16:07:40Z")
So, just how effective are these things? When, if ever, has chaff been deployed in the defense of a ship in actual combat? Did it work? Chaff wasn’t deployed in the Sheffield attack. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 15, 2021, 5:53pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/13 "2021-06-15T17:53:42Z")
All of the other posts are talking about chaff being used as a decoy. Am I just imagining that it’s also used for area-denial against aircraft? I mean, I can’t imagine that it’d be good for a jet engine to fly through a chaff cloud. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [June 15, 2021, 6:08pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/14 "2021-06-15T18:08:17Z")
> [@Chronos](#): > > Am I just imagining that it’s also used for area-denial against aircraft? I mean, I can’t imagine that it’d be good for a jet engine to fly through a chaff cloud. For a while that works, until the chaff falls to the ground[\*] or is dispersed by winds. But it could also work against those doing the area denial. Flying above a chaff cloud is an excellent way to hide from search radar. [\*] Or gets caught in power lines and shorts them out. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [June 15, 2021, 7:48pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/15 "2021-06-15T19:48:30Z")
> [@Chronos](#): > > Am I just imagining that it’s also used for area-denial against aircraft? I mean, I can’t imagine that it’d be good for a jet engine to fly through a chaff cloud. I can’t answer to GQ quality, but here’s some semi-informed thinking … Back in my day the idea of chaff as aerial hazard was never discussed as a problem. Either using yours to harm the enemy or being harmed by theirs. (Or yours; as the saying goes: “Friendly fire … isn’t.”) The airborne cannisters we launched were very thin-walled aluminum tubes on the order of 1"+ in diameter and 8" long which promptly burst apart in the airstream. Even though they each contained umpteen million little slivers of aluminized ultrafine glass fiber, the total volume of material was only a few cubic inches. Which rapidly disperses over a few thousand cubic meters of air. A sufficiently dense cloud of such aluminum and glass would certainly be bad, akin to flying through a volcanic ash cloud. But the output of a volcano is measured in tons per minute, not ounces per each. ---
**Author:** ![Dissonance](https://avatars.discourse-cdn.com/v4/letter/d/85f322/32.png) [@Dissonance](https://boards.straightdope.com/u/Dissonance)\ **Post date:** [June 15, 2021, 10:45pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/16 "2021-06-15T22:45:22Z")
> [@MikeF](#): > > So, just how effective are these things? When, if ever, has chaff been deployed in the defense of a ship in actual combat? Did it work? Chaff wasn’t deployed in the Sheffield attack. During the 1973 Arab-Israeli War [Israeli vessels were “targeted by as many as 52 Soviet-made anti-ship missiles”, but none hit their targets.](https://en.wikipedia.org/wiki/Yom_Kippur_War#Naval_War) How much of that was due to chaff/flares and how much was due to ECM is anyone’s guess. In 1988 during [Operation Praying Mantis](https://en.wikipedia.org/wiki/Operation_Praying_Mantis) the Iranian missile boat _Joshan_ fired a Harpoon at US vessels that “was successfully lured away by chaff,” and some HY-4 Silkworm missiles were later fired at SAG (Suface Action Group) Delta and the frigate USS _Gary_ “but all missed because of evasive maneuvers and use of decoys by the ships. A missile was probably shot down by _Gary_ 's 76 mm (3.0 in) gun. The Pentagon and the Reagan Administration later denied that any Silkworm missile attacks took place, possibly in order to keep the situation from escalating further - as they had promised publicly that any such attacks would merit retaliation against targets on Iranian soil.” During Desert Storm in 1991, the battleship USS _Missouri_ was attacked by a Seersucker anti-ship missile. The missile was ultimately destroyed by a Sea Dart missile fired by HMS _Gloucester_, but accounts vary as to if the Seersucker had already been decoyed away by the _Missouri’s_ chaff and/or jammers before being destroyed. There is a _really, really_ deep-dive into the incident [here](https://wwiiafterwwii.wordpress.com/2019/07/21/missile-attack-on-battleship-uss-missouri/). ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [June 15, 2021, 11:24pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/17 "2021-06-15T23:24:07Z")
> [@Dissonance](#): > > A missile was probably shot down by _Gary_ 's 76 mm (3.0 in) gun. That’s some nice shooting. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [June 16, 2021, 2:40am UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/18 "2021-06-16T02:40:03Z")
Radar guided anti-aircraft cannon are a thing. A rather deadly thing if you’re a jet. Yep, even the main battery on a DD does double duty as anti-aircraft. The “missile” in question was probably more of a cruise missile with aircraft-like performance versus a sea skimmer with supersonic performance. Muc hless the current and immediate future hypersonic perfornance. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 16, 2021, 1:57pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/19 "2021-06-16T13:57:31Z")
> [@Dissonance](#): > > During the 1973 Arab-Israeli War [Israeli vessels were “targeted by as many as 52 Soviet-made anti-ship missiles”, but none hit their targets.](https://en.wikipedia.org/wiki/Yom_Kippur_War#Naval_War) How much of that was due to chaff/flares and how much was due to ECM is anyone’s guess. Also don’t forget to account for how much was due to the missiles just sucking. Remember all those stories from the 1990s Gulf War, about Patriot missiles shooting down Scuds? It turns out that almost all of those were just the Scuds failing on their own. ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [June 16, 2021, 2:08pm UTC](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169/20 "2021-06-16T14:08:47Z")
> [@Chronos](#): > > It turns out that almost all of those were just the Scuds failing on their own. At that stage in a ballistic missile’s flight, that’s all they can do. An anti-ballistic missile is aiming for a warhead kill, attempting to pre-detonate or disarm the only part of the missile intended to do damage. Apparently it happened sometimes, although not as often as initially claimed. (For instance, a Patriot hit on the body of the missile at that stage would still look impressive but could leave the warhead intact to do its damage at the target.) [Next page](https://boards.straightdope.com/t/super-rapid-blooming-overhead-chaff/944169.md?page=2)