Classifications

• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06C—DETONATING OR PRIMING DEVICES; FUSES; CHEMICAL LIGHTERS; PYROPHORIC COMPOSITIONS
  • C06C15/00—Pyrophoric compositions; Flints
• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B29/00—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate
  • C06B29/02—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate of an alkali metal
  • C06B29/12—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate of an alkali metal with carbon or sulfur
• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B29/00—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate
  • C06B29/02—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate of an alkali metal
  • C06B29/16—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate of an alkali metal with a nitrated organic compound
  • C06B29/20—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate of an alkali metal with a nitrated organic compound the compound being nitrocellulose
• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B29/00—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate
  • C06B29/22—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate the salt being ammonium perchlorate

Definitions

• the present invention relates to an infra-red decoy flare.
• infra-red guided missiles are often used against aircrafts such as jet aircraft, transport aircrafts and helicopters. These missiles can be launched from the ground or from, for instance, another aircraft, and they are used to target on and track the infra-red radiation of a certain wavelength range which is emitted by the engine of the target aircraft.
• decoy flares are used. Such decoy flares produce infra-red radiation, causing the missile to follow the decoy flare instead of the target aircraft.
• CCM counter-countermeasures
• MTV decoy flares Magnetic-Teflon— Viton
• Efforts have therefore been made to develop decoy flares that generate infra-red colour ratios that are more similar to those of target aircrafts.
• Boron-based and red phosphorous-based pyrotechnic compositions have, for example, been developed for this purpose, but their performance leaves much room for improvement.
• Object of the present invention is to provide improved infra-red decoy flares effectively defending aircrafts against missiles that are equipped with CCM systems.
• the present invention relates to an infra-red decoy flare comprising a pyrotechnic composition which comprises an extrudable and energetic binder in an amount in the range of from 4-35 wt%, which binder comprises a nitrocellulose, an oxidator in an amount in the range of from 40-80 wt%, a pyrotechnic fuel in an amount in the range of from 15-35 wt%, and a carbon source in an amount of up to and including 10 wt%, all amounts based on total pyrotechnic composition.
• a pyrotechnic composition which comprises an extrudable and energetic binder in an amount in the range of from 4-35 wt%, which binder comprises a nitrocellulose, an oxidator in an amount in the range of from 40-80 wt%, a pyrotechnic fuel in an amount in the range of from 15-35 wt%, and a carbon source in an amount of up to and including 10 wt%, all amounts based on total
• the Infra-red decoy flares according to the present invention display an excellent burning rate, whereas at the same time their compositions can be easily adjusted to conform to the desired colour ratio.
• Another advantage is that their production require less or no solvents and that these solvents have less impact on the environment than the solvents used in conventional production. Additionally, the solvents used has significant advantages in relation to the explosive limits and ignition point. Yet another and substantial advantage of the present infra-red decoy flares is that the pyrotechnic composition used therein is extrudable, which allows for the very easy and save production of decoy flares in a continuous mode of operation. Additionally, during processing the safety is increased because the pyrotechnic mixture burns less violent due to the presence of the solvent.
• the binder to be used according to the present invention is extrudable and energetic. With the term energetic is meant that the binder will decompose exothermically.
• the extrudable and energetic binder to be used in accordance with the present invention comprises a nitrocellulose.
• the nitrocellulose is a low nitrogen content nitrocellulose.
• a low nitrogen content nitrocellulose is defined as a nitrocellulose having a nitrogen content of less than 11.3% wt%.
• the oxidator to be used in the pyrotechnic composition according to the present invention is preferably is selected from the group consisting OfKClO 4 , KCIO3 and NH4CIO4. More preferably, the oxidator comprises KICO4.
• the extrudable and energetic binder comprises a nitrocellulose, preferably a low nitrogen content nitrocellulose whereas the oxidator comprises KClO 4 .
• the pyrotechnic fuel to be used in accordance with the present invention can suitably be selected from the group consisting of terephthalic acid phenolphthalein, phthalic anhydride, benzoyl peroxide, 4-amino benzoic acid, sodium salicylate, potassium salicylate, barium salicylate, strontium salicylate, potassium hydrogen phthalate, sodium hydrogen phthalate, barium hydrogen phthalate, strontium hydrogen phthalate, (i.e.
• the pyrotechnic fuel to be used in accordance with the invention may be applied in liquid form as well as in powder form.
• the pyrotechnic fuel to be used in accordance with the present invention is preferably selected from the group consisting of terephthalic acid phenolphthalein, phthalic anhydride, benzoyl peroxide, 4-amino benzoic acid, sodium salicylate, potassium hydrogen phthalate, benzophenone, dodecane, potassium benzoate, 4-nitro benzoic acid, 3-nitro benzoic acid, 5-amino tetrazole, ascorbic acid, sodium di-iso ascorbate, L-ascorbic acid, stearic acid, sodium benzoate, dinitro benzoic acid and potassium dinitro benzoate.
• the pyrotechnic fuel may be applied in liquid form as well as in powder form. More preferably, the pyrotechnic fuel is selected from the group consisting of potassium dinitrobenzoate, terephthalic acid, sodium salicylate, sodium di-isoascorbate, 3,5-dinitrobenzoic acid, 4-ar ⁇ inobenzoic acid, L- ascorbic acid, ascorbic acid, and sodium benzoate.
• the pyrotechnic fuel comprises potassium dinitrobenzoate, terephthalic acid, sodium salicylate or sodium-D ascorbate
• the extrudable and energetic binder comprises a nitrocellulose, preferably a low nitrogen content nitrocellulose
• the oxidator comprises KClO 4
• the pyrotechnic fuel comprises potassium dinitrobenzoate or sodium-D ascorbate.
• the carbon source to be used in accordance with the present invention may comprise lampblack, soot, graphite, charcoal, coal, or for those skilled in the art functionally equal materials.
• the carbon source comprises lampblack or graphite
• the carbon source comprises lampblack.
• the extrudable and energetic binder is present in an amount of 4-35 wt%, based on total pyrotechnic composition.
• the binder is present in an amount in the range of from 10-15 wt%, based on total pyrotechnic composition.
• the oxidator is present in the pyrotechnic composition to be used in accordance with the present invention in an amount in the range of from 40-80 wt%, based on total pyrotechnic composition.
• the oxidator is present in an amount in the range of from 40 - 72 wt%, more preferably in an amount in the range of from 48 — 61 wt%, based on total pyrotechnic composition.
• the pyrotechnic fuel to be used in the present infra-red decoy flares is present in an amount in the range of from 15-35 wt%, based on total pyrotechnic composition.
• the pyrotechnic fuel is present in an amount in the range of from 16 - 31 wt%, more preferably in an amount in the range of from 17 - 28 wt%, based on total pyrotechnic composition.
• the carbon source is present in the pyrotechnic composition to be used in accordance with the present invention in an amount up to and including 10 wt%, based on total pyrotechnic composition.
• the chosen amount of carbon source will depend on the performance requirements for the infra-red decoy flare concerned.
• the carbon source is present in an amount in the range of 1 to 5 wt%, based on total pyrotechnic composition.
• the pyrotechnic composition to be used in accordance with the present invention may include other conventional components (burn rate modifier, stabilizer, processing additives, flegmatizer, etc.) which are common for those skilled in the art. If present, these components will be present in an amount of less than 10 wt%, based on total pyrotechnic composition.
• the present invention also relates to a process for preparing the infrared decoy flare according to the present invention, wherein an extrudable and energetic binder in an amount in the range of from 4-35 wt%, which binder is a nitrocellulose, an oxidator in an amount in the range of from 40-80 wt%, a pyrotechnic fuel in an amount in the range of from 15-35 wt%, and a carbon source in an amount of up to 10 wt%, all amounts based on total pyrotechnic composition, are mixed, preferably by means of an extruder, and the mixture (extrudate) so obtained is subsequently pressed in the desired form.
• the process is carried out in the presence of a solvent that is selected from the group consisting of ethanol, or solvents esters such as ethyl acetate, butyl acetate, or alcohols such as isopropanol butanol.
• a solvent that is selected from the group consisting of ethanol, or solvents esters such as ethyl acetate, butyl acetate, or alcohols such as isopropanol butanol.
• solvents have the advantage, when compared with conventionally used solvents such as acetone and hexane, that they have a less impact an the environment and that reduce the risk of safety hazards (explosions) considerably.
• the solvent comprises ethanol.
• the solvent is suitably present in an amount in the range of from 0 to 20 wt%, based on total pyrotechnic composition.
• the solvent is present in an amount in the range of from 5 to.14 wt%, based on total mixture. It will be understood by the skilled person that said solvent will in essence not be present in the pyrotechnic composition eventually obtained, due to evaporation of the solvent concerned.
• the infra-red decoy flares in accordance with the present invention Upon release the infra-red decoy flares in accordance with the present invention will be ignited, and they will be burnt at a sufficient rate and produce enough infra-red emission to ensure that the infra-red guided missile is unlocked, and that it will be prevented from locking back onto the trace of the target aircraft.
• the infra-red decoy flare in accordance with the present invention may have the form of a cartridge or a pellet. Its design may be conventional. It may, for instance, have the shape of a pellet or cartridge.
• the outer surface of the pellet or cartridge can suitably provided with grooves so as to establish an improved burning rate. Said grooves can be rectilinear and longitudinal. It should be noted that the shape and the disposition of the grooves can be chosen by the skilled person from a wide range of known possibilities. However, in order to ensure that the infra-red decoy flare will operate effectively it will need to have an aerodynamic shape. Further, it will be understood that the infra-red decoy flare will comprise an ignition means to ignite the pyrotechnic composition.
• Composition 1 is a composition of Composition 1:
• Composition 2 is a composition of Composition 2:
• compositions 1 and 2 were premixed and fed into the first solid feeder of the extruder, the second solid feeder contained KCIO4.
• the extruder was a Theyson Twin Screw Extruder, (co-rotating self wiping, 45mm, 1305 mm screw length, 29 L/D).
• the extruder barrel temperature was set at 50°C, at 25 rounds per minute.
• the ethanol liquid feed was set to obtain 9% (m/m) ethanol.
• the resulting extruder rods (flares) obtained from the respective compositions 1 and 2 were perforated strands.
• IR emissions were measured using a Nicolet Nexus FTIR spectrometer with MCT-B wide range detector (Mercury Cadmium Telluride) with beamsplitter and spectral range set to 0.9 — 10 ⁇ m.
• the distance between the FTIR and flare was 21 meter.
• the relative humidity was 51% and temperature 17.5 °C.
• the infra-red decoy flares prepared from respective compositions 1 and 2 were determined to be both spectrally balanced.

Applications Claiming Priority (2)

Publications (1)

Family

ID=36123929

Family Applications (1)

Country Status (4)

Families Citing this family (5)

Family Cites Families (8)

• 2005
  • 2005-07-06 NL NL1029465A patent/NL1029465C2/nl not_active IP Right Cessation
• 2006
  • 2006-06-07 US US11/988,170 patent/US20090120545A1/en not_active Abandoned
  • 2006-07-06 EP EP06757822A patent/EP1904421A2/de not_active Withdrawn
  • 2006-07-06 WO PCT/NL2006/000339 patent/WO2007004871A2/en active Application Filing

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events