Recent from talks
Nothing was collected or created yet.
Mark 77 bomb
View on Wikipedia
The Mark 77 bomb (MK-77) is a United States 750-pound (340 kg) air-dropped incendiary bomb carrying 110 U.S. gallons (416 L; 92 imp gal) of a fuel gel mix which is the direct successor to napalm.
Key Information
The MK-77 is the primary incendiary weapon currently in use by the United States military. Instead of the gasoline, polystyrene, and benzene mixture used in napalm bombs, the MK-77 uses kerosene-based fuel with a lower concentration of benzene. The Pentagon has claimed that the MK-77 has less impact on the environment than napalm. The mixture reportedly also contains an oxidizing agent, making it more difficult to put out once ignited, as well as white phosphorus.[1][2]
The effects of MK-77 bombs are similar to those of napalm. The official designation of World War II-era napalm bombs was the Mark 47.[3]
Use of aerial incendiary bombs against civilian populations, including against military targets in civilian areas, was banned in the 1980 United Nations Convention on Certain Conventional Weapons Protocol III. However, the United States reserved the right to use incendiary weapons against military objectives located in concentrations of civilians where such use would be determined to cause fewer casualties and/or less collateral damage than alternative weapons.[4]
Use in Iraq and Afghanistan
[edit]MK-77s were used by the United States Marine Corps during Operation Desert Storm[5] and Operation Iraqi Freedom.[6] Approximately 500 were dropped, reportedly mostly on Iraqi-constructed oil filled trenches. They were also used at the Battle of Tora Bora during the Afghan War.[2]
At least thirty MK-77s were also used by Marine Corps aviators over a three-day period during the 2003 invasion of Iraq, according to a June 2005 letter from the UK Ministry of Defence to former Labour MP Alice Mahon. This letter stated:
The U.S. destroyed its remaining Vietnam era napalm in 2001 but, according to the reports for I Marine Expeditionary Force (I MEF) serving in Iraq in 2003, they used a total of 30 MK 77 weapons in Iraq between 31 March and 2 April 2003, against military targets away from civilian areas. The MK 77 firebomb does not have the same composition as napalm, although it has similar destructive characteristics. The Pentagon has told us that owing to the limited accuracy of the MK 77, it is not generally used in urban terrain or in areas where civilians are congregated.[7]
This confirmed previous reports by U.S. Marine pilots and their commanders saying they had used Mark 77 firebombs on military targets:
Then the Marine howitzers, with a range of 30 kilometers [181⁄2 mi], opened a sustained barrage over the next eight hours. They were supported by U.S. Navy aircraft which dropped 40,000 pounds [18,000 kg] of explosives and napalm, a U.S. officer told the Herald. "We napalmed both those [bridge] approaches," said Colonel James Alles, commander of Marine Aircraft Group 11. "Unfortunately there were people there ... you could see them in the cockpit video. They were Iraqi soldiers."
According to the Italian public service broadcaster RAI's documentary Fallujah, The Hidden Massacre, the MK 77 had been used in Baghdad in 2003 in civilian-populated areas. However, Marine pilots stated to the San Diego Union-Tribune that the targets of the bombings were Iraqi soldiers defending civilian infrastructure such as bridges, as opposed to targeting civilians directly.[8]
In some cases where journalists reported that the U.S. military has used napalm, military spokesmen denied the use of "napalm" without making it clear that MK-77 bombs had actually been deployed instead.[2][9]
U.S. officials incorrectly informed UK Ministry of Defence officials that MK-77s had not been used by the U.S. in Iraq, leading to Defence Minister Adam Ingram making inaccurate statements to the UK Parliament in January 2005.[10] Later both Adam Ingram and Secretary of State for Defence John Reid apologized for these inaccurate statements being made to Members of Parliament.
Variants
[edit]Later variants of the bomb were modified to carry a reduced load of 75 U.S. gallons (284 L; 62 imp gal) of fuel, which resulted in the total weight decreasing to around 552 pounds (250 kg).
- Mk 77 Mod 0 - 750 lb (340 kg) total weight with 110 U.S. gallons (416 L; 92 imp gal) of petroleum oil.
- Mk 77 Mod 1 - 500 lb (230 kg) total weight with 75 U.S. gallons (284 L; 62 imp gal) of petroleum oil.
- Mk 77 Mod 2
- Mk 77 Mod 3
- Mk 77 Mod 4 - Approx 507 lb (230 kg) total weight with 75 U.S. gallons (284 L; 62 imp gal) of fuel (Used during the 1991 Gulf War)
- Mk 77 Mod 5 - Approx 507 lb (230 kg) total weight with 75 U.S. gallons (284 L; 62 imp gal) of JP-4/JP-5 or JP-8 fuel and thickener (Used during the 2003 invasion of Iraq)
- Mk 78 - 750 lb (340 kg) total weight with 110 U.S. gallons (416 L; 92 imp gal) of petroleum oil. No longer in service.
- Mk 79 - 1,000 lb (450 kg) total weight with 112 U.S. gallons (424 L; 93 imp gal) of napalm and petrol. No longer in service.
See also
[edit]References
[edit]- ^ RAI documentary, English, Italian, Arabic
- ^ a b c MK-77, GlobalSecurity.org
- ^ MK-77 - Dumb Bombs
- ^ "CCW Protocol III 1980 - United States of America reservation text". icrc.org. Archived from the original on 1 April 2013. Retrieved 20 June 2009.
- ^ AR 600-8-27 p. 26 paragraph 9-14 & p. 28
- ^ Napalm
- ^ "UK Ministry of Defence letter to Alice Mahon (document)". Archived from the original on 17 July 2012. Retrieved 8 December 2005.
- ^ Officials confirm dropping firebombs on Iraqi troops Archived 21 February 2016 at the Wayback Machine
- ^ U.S. acknowledgment of use of "napalm" (i.e. MK-77) and white phosphorus
- ^ UK Parliament 10 Jan 2005 UK Parliament 11 Jan 2005 Archived 28 July 2005 at the Wayback Machine
Endnotes
[edit]- MK-77 Dumb Bombs, Federation of American Scientists
- Lennox, Duncan (1994). Jane's Air-Launched Weapons 2005-2006. ISBN 978-0-7106-0866-6.
- Army Regulations 600-8-27 dated 2006
External links
[edit]- 'Dead bodies are everywhere', Sydney Morning Herald, 22 March 2003 - probably the first published report on Mk 77 use in Iraq
- Napalm by another name: Pentagon denial goes up in flames, Sydney Morning Herald, 9 August 2003
- US State Department Response to Illegal Weapon Allegations, 27 January 2005
- US lied to Britain over use of napalm in Iraq war, The Independent, 17 June 2005
- Parliament misled over firebomb use, Daily Telegraph, 20 June 2005
- The Hidden Massacre by Sigfrido Ranucci, Video documentary shows actual chemical bombing on civilians in Fallujah with testimony of interviewed U.S. soldiers - English, Italian and Arabic Archived 1 December 2005 at the Wayback Machine, Rai News 24, 8 November 2005
- US forces 'used chemical weapons' during assault on city of Fallujah, The Independent, 9 November 2005
Mark 77 bomb
View on GrokipediaDevelopment and History
Origins as Incendiary Weapon
The Mark 77 bomb was developed by the United States Navy in the early 1950s as a 750-pound incendiary munition designed to deliver sustained fire against soft targets, including dug-in troops and exposed materiel.[1] Its primary mechanism involves a thin aluminum casing filled with approximately 110 gallons of a kerosene-based fuel gel mixture, which a small high-explosive burster disperses upon impact to create a large area of burning gel that adheres to surfaces and resists extinguishment.[1] [2] This configuration evolved from World War II-era incendiary bombs such as the M-47, which used similar gelled fuels for area denial, but scaled up for greater payload and dispersion effectiveness in post-war carrier-based aviation.[1] Initial testing of the Mk 77 Mod 0 occurred in February 1953 at the U.S. Naval Proving Ground in Dahlgren, Virginia, focusing on modifications to reduce capacity to 75 gallons for improved aircraft handling during catapult launches and arrested landings on carriers.[3] These evaluations confirmed the bomb's operational viability for low-altitude, high-speed delivery from naval aircraft, emphasizing its role in generating intense, persistent flames to deny terrain and incinerate targets without relying on fragmentation or blast effects.[3] The fuel gel, distinct from later napalm-B formulations by using a gelling agent with lower benzene concentrations and additives like oxidizing agents for enhanced ignition, prioritized clinginess and burn duration over explosive yield.[2] Unlike high-explosive ordnance, the Mk 77's incendiary origins reflect a doctrinal emphasis on psychological and suppressive effects through fire, building on lessons from incendiary campaigns in prior conflicts where gelled fuels proved effective against concealed positions in vegetated or urban environments.[1] Early variants lacked stabilization fins, relying on aircraft release dynamics for unguided dispersion, which aligned with its purpose as a low-precision area weapon rather than a pinpoint strike tool.[2] Subsequent modifications, such as canted fins tested in the mid-1950s, refined trajectory stability without altering the core incendiary payload.[5]Post-Vietnam Adaptations and Production
Following the Vietnam War, the U.S. military phased out traditional napalm production, destroying the last filled napalm canisters by March 2001, while adapting the Mark 77 bomb as its primary incendiary munition.[1] This evolution from earlier M-47 and M-74 bombs involved shifting the fuel gel composition from gasoline thickened with benzene and polystyrene to a kerosene-based jet fuel mixture gelled with polystyrene and augmented by an oxidizing agent, producing a similar sticky, incendiary effect without the napalm designation.[6] The adaptation addressed post-war scrutiny over incendiary weapons, including public backlash and the 1980 Convention on Certain Conventional Weapons' Protocol III restricting use against civilians, by emphasizing employment against military targets like entrenched troops.[1] The Mark 77's design was refined for U.S. Navy carrier operations, featuring a thin-skinned aluminum casing without stabilizing fins to prioritize fragmentation and fuel dispersal over precision, with variants such as Mod 0 tested for structural integrity under catapult stresses up to 15.1 g forward.[7] Later modifications, including reduced fuel loads to 75 U.S. gallons in some configurations, decreased total weight from the standard 750 pounds to enhance aircraft compatibility and payload efficiency.[5] Production occurred in limited batches post-Vietnam, tailored for specific contingencies rather than mass stockpiling, with several hundred units manufactured in the 1990s to support naval aviation.[1] This enabled deployment of approximately 500 Mark 77 bombs during the 1991 Persian Gulf War, primarily against Iraqi forces in open trenches.[8] The U.S. maintained the Mark 77 as its sole incendiary bomb type into the 2000s, producing additional quantities as needed for operations in Iraq and Afghanistan, underscoring its niche role in area-denial against soft targets.[6]Design and Technical Specifications
Composition and Fuel Gel Mixture
The MK-77 bomb is filled with approximately 110 US gallons (416 L) of a gelled fuel mixture that serves as its primary incendiary agent, enabling the weapon to disperse burning gel upon rupture of its thin aluminum casing.[1] Early variants, such as the Mod 0, employed napalm as the filler, weighing about 668 lb (303 kg), which consisted of gasoline thickened with a polystyrene and benzene admixture to create a sticky, persistent incendiary.[9] Subsequent modifications, including the Mod 5 used in operations post-1991, shifted to a kerosene-based jet fuel (such as JP-5 or similar) thickened primarily with polystyrene, reducing reliance on benzene compared to napalm-B's formulation of roughly 46% gasoline, 33% benzene, and 21% polystyrene.[10] This adjustment aimed to mitigate toxicity concerns associated with benzene while maintaining the gel's adhesive and combustion properties, allowing sustained burning at temperatures exceeding 1,000°C (1,800°F) over targeted areas.[8] The gel's viscosity ensures it fragments into clumps upon impact, promoting wide-area fire coverage rather than immediate evaporation.[2] Ignition is provided by pyrotechnic charges rather than a high-explosive burster, preserving the fuel's integrity until dispersal and activation, which enhances effectiveness against soft targets like vegetation or personnel in the open.[1] This composition renders the MK-77 a tactical incendiary distinct from conventional high-explosive ordnance, optimized for denial of area through fire rather than blast fragmentation.[10]Physical Characteristics and Delivery Mechanisms
![Mark 77 bomb loaded on F/A-18 Hornet][float-right] The Mark 77 bomb features a thin-walled, cigar-shaped aluminum body designed for fragmentation upon impact to disperse its incendiary filler. Standard configurations lack stabilizing fins, classifying it as a non-stabilized, unguided munition.[9] The Mod 0 variant weighs 750 pounds (340 kg) total, containing 668 pounds (303 kg) of napalm gel filler, while the Mod 1 and Mod 4 variants are lighter at approximately 500 pounds (227 kg), with a filler capacity of about 75 gallons (284 L) or 450 pounds (204 kg) of gelled gasoline or kerosene-based mixture.[9][11] Suspension is provided by two lugs spaced 14 inches (36 cm) apart on the body, enabling compatibility with standard bomb racks.[11] Ignition is achieved through nose and tail igniters, such as the M23 with AN-M173 fuze, which activate on impact to ignite the dispersed fuel gel; variants may incorporate white phosphorus, sodium, or magnesium-Teflon for enhanced ignition against land or water targets.[9][11] The bomb's thin skin ensures rapid rupture, promoting wide-area fire coverage rather than structural integrity post-impact.[1] Delivery occurs via free-fall release from fixed-wing aircraft, primarily carrier-based fighters like the F/A-18 Hornet employed by the U.S. Marine Corps.[12] Drops are typically conducted at low altitudes to optimize the incendiary pattern and minimize wind dispersion of the fuel gel.[12] The munition attaches to multiple-ejector racks or single stations, with release mechanisms using pneumatic pistons to impart initial separation from the pylon.[13] No guidance systems are integrated, relying on the pilot's aim and aircraft stability for targeting.[1]Variants and Modifications
Predecessor and Successor Models
The Mark 77 incendiary bomb evolved from earlier U.S. napalm munitions, specifically the M-47 and M-74 bombs deployed in the Korean War (1950–1953) and Vietnam War (1955–1975).[1] The M-47, a 500-pound bomb containing approximately 110 U.S. gallons of napalm (a mixture of gasoline thickened with polystyrene), served as the primary unguided incendiary weapon for area denial and anti-personnel effects prior to international prohibitions on napalm following the 1972 U.S. suspension of its use.[1] The M-74, a cluster-dispenser variant, released smaller napalm-filled submunitions for broader fire coverage.[1] No direct successor models have replaced the Mark 77 in U.S. service as an unguided fuel-gel incendiary bomb, though incremental modifications—such as Mod 2, Mod 3, and Mod 4—refined its design for improved dispersal and reduced weight, with the Mod 4 variant totaling about 507 pounds including 75 U.S. gallons of fuel gel and seeing use in the 1991 Gulf War.[1] Related firebomb designations like the MK-78 (500-pound) and MK-79 (1,000-pound) represent scaled variants within the same family rather than sequential successors.[1] Precision guidance kits, such as the Joint Direct Attack Munition (JDAM), have been integrated with Mark 77 casings for enhanced accuracy in recent operations, but these do not constitute new bomb models.Specialized Configurations
The Mark 77 bomb features several modifications tailored to operational requirements, primarily differing in payload capacity, fuel gel composition, and structural adaptations for aerial delivery. The Mod 0 configuration is a 750-pound (340 kg) non-stabilized, cigar-shaped aluminum bomb designed for incendiary effects against both land and maritime targets, containing approximately 110 U.S. gallons (416 liters) of gelled fuel mixture.[9] This variant emphasizes high-volume fire coverage through aerodynamic ejection from low-altitude, high-speed aircraft.[2] The Mod 1 adaptation reduces the bomb's weight to 500 pounds (227 kg) by modifying the Mod 0 casing to hold 75 U.S. gallons (284 liters) of fuel gel, enabling compatibility with a broader range of carrier aircraft while retaining incendiary functionality for area denial.[11] Handling equipment, such as specialized bands, supports assembly and loading for this lighter variant.[14] Later iterations, including Mods 4, 5, and 6, incorporate refined fuel gels for improved safety, stability, and reduced toxicity compared to earlier gasoline-benzene blends. The Mod 5 specifically employs a kerosene-based jet fuel gel with lower benzene content, weighing approximately 507 pounds (230 kg) and carrying 75 gallons (284 liters), optimized for forcible ejection and sustained combustion in diverse environments.[1][2] Mods 4 and 5 primarily differ in gel formulation to enhance ignition reliability and minimize premature dispersal risks during transit.[2] These configurations pair with dedicated fuzing, such as the MK 13 initiator exclusive to Mod 5, to ensure precise arming sequences.[15] Production of these mods sustained U.S. Navy training and deployment needs into the early 21st century, with adaptations reflecting post-Vietnam shifts toward less volatile energetics.[16]Operational Deployment
Use in 2003 Iraq Invasion
U.S. Marine Corps aircraft deployed the Mark 77 bomb during the early stages of Operation Iraqi Freedom, the 2003 invasion of Iraq, primarily to target Iraqi Republican Guard positions and other military assets during the ground advance toward Baghdad. On March 31, 2003, as coalition forces pushed northward from Kuwait, Marine aviators released the first of these incendiary weapons against troop concentrations, leveraging the bomb's ability to create sustained fire over area targets to disrupt enemy formations and fortifications. Delivery was typically via AV-8B Harrier jump jets, which carried the 750-pound munitions from forward operating bases or aircraft carriers in the Persian Gulf.[1][4] Between March 31 and April 2, 2003, U.S. forces expended approximately 30 Mark 77 bombs on designated military objectives, selected to avoid proximity to civilian populations, as per operational records cited in subsequent disclosures. These strikes were part of broader close air support missions supporting the 1st Marine Expeditionary Force's rapid maneuver through southern Iraq, where the bombs' gel fuel mixture proved effective in igniting fuel depots and armored vehicle clusters amid urban-adjacent terrain. Pre-positioned stocks, including hundreds of partially loaded units on maritime prepositioning ships, facilitated rapid deployment from storage in Diego Garcia and other regional sites, enabling sustained sorties without immediate resupply delays.[17] Pentagon officials confirmed the employment of these firebombs in August 2003, emphasizing their role in neutralizing paramilitary holdouts while adhering to rules of engagement that prioritized precision over indiscriminate area denial. No verified instances of use extended beyond the initial invasion phase into prolonged occupation operations, with total deployments remaining limited compared to conventional ordnance like precision-guided munitions. Post-action assessments by Marine aviation units highlighted the Mark 77's utility in low-threat environments for psychological impact on exposed infantry, though logistical constraints—such as the need for manual fuze setting and vulnerability to anti-aircraft fire—restricted broader application.[4][1]Employment in Afghanistan Operations
The Mark 77 bomb (MK-77) was not employed by U.S. forces during operations in Afghanistan, in contrast to its documented use in the 2003 Iraq invasion.[8] U.S. military statements have explicitly denied the deployment of napalm or equivalent incendiary munitions, including the MK-77, in Afghan theater engagements following the 2001 invasion.[18] This absence aligns with operational preferences for precision-guided munitions and conventional explosives in rugged, populated terrains where area-denial incendiaries posed higher risks of unintended spread due to variable wind and vegetation conditions.[1] Claims of MK-77 use in Afghanistan have surfaced in advocacy reports but lack corroboration from declassified military records or independent verification, often conflating it with other fire-starting agents like white phosphorus employed for illumination or screening rather than primary incendiary effects. No specific strike incidents, sortie data, or after-action reviews attribute MK-77 drops to Afghan missions across major phases like Operation Enduring Freedom (2001–2014) or Resolute Support (2015–2021). U.S. Central Command and Marine Corps deployment logs emphasize alternatives such as Joint Direct Attack Munitions (JDAMs) and thermobaric weapons for close air support against insurgent positions.Military Rationale and Effectiveness
Tactical Advantages in Urban and Insurgent Warfare
The Mark 77 bomb provides standoff fire-starting capability against insurgents embedded in urban structures, where close-quarters combat otherwise exposes ground forces to ambushes, improvised explosive devices, and fortified positions. Its payload of approximately 110 gallons of gelled JP-4/PS kerosene mixture disperses upon impact to cover an area of up to 200 meters, igniting combustibles and sustaining burns that penetrate light cover such as wooden or masonry buildings common in insurgent-held cities.[8] This mechanism reduces the necessity for infantry to conduct risky room-to-room clearances, which in operations like the 2004 Second Battle of Fallujah resulted in over 50 U.S. fatalities during initial assaults on booby-trapped homes.[19] By consuming oxygen and generating dense smoke, the resulting fires can flush hidden fighters into open kill zones or neutralize them through thermal and asphyxiation effects, exploiting the insurgents' reliance on concealment over mobility.[20] In insurgent warfare, where adversaries operate in decentralized cells within civilian-integrated urban grids, the bomb's area-denial properties hinder re-infiltration and logistics, as sustained conflagrations render zones temporarily uninhabitable and destroy caches of ammunition or fuel often stored indoors.[20] Unlike kinetic munitions that may leave structures intact for reuse, the incendiary effect structurally weakens buildings through charring and collapse, based on the gel's adhesion and combustion temperature exceeding 1,000°C, which exceeds the ignition points of typical urban materials like drywall and furniture.[8] U.S. military assessments of similar flame-based systems highlight their efficacy against cave and bunker networks adaptable to urban analogs, minimizing troop exposure while imposing psychological disruption on fighters unaccustomed to prolonged fire threats.[20] Comparative doctrine from Marine Corps urban operations emphasizes that such weapons complement precision strikes by addressing dispersed, low-signature threats, with empirical tests showing incendiaries outperform blast effects in propagating through enclosed spaces riddled with insurgents. However, deployment requires accounting for wind and fuel volatility to optimize scatter patterns, ensuring maximal coverage against clustered positions while adhering to targeting protocols that prioritize verifiable military utility over incidental spread.[21]Empirical Outcomes and Comparative Analysis
The Mk-77 bomb, deployed by U.S. Marine Corps AV-8B Harrier and F/A-18 aircraft during the March-April 2003 invasion of Iraq, targeted entrenched Iraqi paramilitary and Fedayeen Saddam forces south of Baghdad, including positions near Nasiriyah. Pentagon officials confirmed its use on August 4, 2003, noting its incendiary effects disrupted defensive lines and supported Marine advances, though aggregated battle damage assessments did not isolate Mk-77-specific casualties from combined arms operations.[4][22] No declassified U.S. military reports publicly quantify enemy fatalities directly attributable to Mk-77 drops, with operational evaluations focusing instead on its role in achieving fire superiority against concealed personnel rather than precise kill counts.[1] In comparative terms, the Mk-77's kerosene-based gel mixture generates sustained combustion and smoke over a dispersed footprint—typically 200-500 square meters depending on release altitude and wind—offering area-denial effects against dug-in infantry that exceed the localized blast radius of equivalent-weight high-explosive (HE) munitions like the 500-pound Mk-82. Unlike HE bombs, which primarily inflict overpressure and fragmentation injuries survivable in covered positions, incendiaries like the Mk-77 cause thermal burns, oxygen depletion, and secondary fires, rendering cover less protective and complicating enemy evacuation or counteraction.[8] Historical data from World War II incendiary campaigns, such as the March 9-10, 1945, Tokyo firebombing with M-69 napalm clusters, demonstrated casualty rates exceeding 100,000 in urban settings through firestorm propagation, a mechanism analogous but less amplified in the Mk-77's unguided, lower-altitude delivery against dispersed modern foes.[23]| Munition Type | Primary Effect | Effective Range/Area | Suitability for Targets |
|---|---|---|---|
| Mk-77 Incendiary | Thermal burn, fire spread, smoke | 200-500 m² fire pattern | Dug-in troops, soft structures, convoys[1] |
| Mk-82 HE (500 lb) | Blast/fragmentation | 20-50 m lethal radius | Point targets, vehicles, light fortifications[24] |