Seeker optics magnify infrared signatures emitted by distant aircraft; keeping track of the target is another matter altogether. The SA-7 and knockoffs of it use simple spin scanners, but the Stinger and more recent designs use conical scanning systems. In con-scan arrangements, portions of light collected by a Cassegrainian primary mirror are reflected by a secondary mirror through a chopper reticle and onto an infrared detector.
After infrared energy is focused by the secondary mirror, it passes through the chopper reticle, a disc with a rotor-like paint scheme—opaque blades alternate with transparent slots. Continue or Give a Gift. Daily Planet. Flight Today. History of Flight. Virtual Space. Improve this question. Add a comment. Active Oldest Votes.
Wikipedia Once the presence of a "live" IR missile is indicated, flares are released by the aircraft in an attempt to decoy the missile; some systems are automatic, while others require manual jettisoning of the flares. Improve this answer. Community Bot 1. Carlo Felicione Carlo Felicione Sign up or log in Sign up using Google.
Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. Featured on Meta. Now live: A fully responsive profile. These compounds are more sensitive than the main magnesium and Teflon flare body and help to ensure proper ignition. The entire flare is protected in a primarily aluminum casing. In order to be effective, the self-protection flare is designed to be ejected from the aircraft and be consumed bum out prior to reaching the ground.
If the flare performs as designed, it will be completely consumed while still in the air, leaving only reaction gases released to the air and solid by-products to reach the ground. Toxicity is not a concern with flares, since the primary material in flares, magnesium, is not highly toxic, and it is highly unlikely that humans or animals would ingest flare material. The main issue with flares is their potential to start fires that can spread and have significant adverse impacts on the environment.
Fires can cause a wide variety of significant secondary effects on personnel safety, soil, water resources, biological resources, land use, visual resources, and cultural resources. Another issue is the potential for dud flares and falling debris to pose safety risks. Although the probability of injury from falling debris was found to be extremely remote, there may be a risk associated with untrained people finding dud flares dropped over land that is not controlled by the Department of Defense.
The frequency of burning flares or associated materials landing on the ground is not information collected in mishap databases, and calculating a probability would involve too many unknown variables to be accurate. However, methodologies exist for predicting the risk that a fire will start and spread.
Using a combination of computer modeling and input databases, with information on meteorological conditions and the flammability of various types of vegetation, the relative risk of wildfires can be predicted. This analysis can only be conducted on a site-specific basis because conditions vary so widely from location to location.
A flare fire risk assessment methodology is presented in this report. Impulse cartridges and initiators used with some flares contain chromium and, in some cases, lead, which are hazardous air pollutants under the Clean Air Act. A screening health risk assessment concluded that they do not present a significant health risk. Laboratory analyses of flare pellets and flare ash indicate that these materials have little potential for affecting soil or water resources, except possibly in small, confined freshwater habitats that support threatened or endangered species.
Potential impacts on biological resources are primarily related to fire. Flare debris is similar to chaff debris, and litter may be a concern in certain pristine areas. However, field studies indicated that debris does not tend to accumulate in noticeable quantities.
The principal issues concerning potential effects on cultural resources are related to fire and associated suppression activities.
No specific studies were conducted on whether Native Americans perceive that flare use affects traditional resources. As with other resources, traditional resources can be adversely affected by ff are-caused fires. Fires resulting from flare use have the potential to cause impacts on a variety of resources.
The degree of impact from fires will depend on the extent and intensity of the fire, the sensitivity of resources to damage by fire, and the value of the affected resources. Fire is part of the natural ecosystem of most plant communities except for the antarctic, hot deserts, and tropical wetlands , and is a major force in all arid, temperate, boreal, and austral zones.
The more fire-prone an ecosystem, the greater the role of natural fire in shaping the ecosystem. Very little has been done in the way of assessing the probability of ignition of a wildland fire by a single source such as a flare.
Since there can be such an abundance of ignition sources, the probability associated with a single source becomes irrelevant to fire management. The release altitude would have to be above 1, feet AGL to ensure complete burn-out of a 10 second flare. The actual burn times of flares are classified, and based on that information, the safe altitude is likely to be significantly lower.
If a burning flare reaches the ground or the canopy of a tree or shrub, it may or may not start a fire. A review of the fire history data in existing flare use areas is documented in Technical Report on Chaff and Flares, Technical Report No. Fires caused by training operations occur in both dry and temperate or humid environments and can occur during times of relatively low fire hazard conditions if ignition sources are present.
The flare training areas examined covered a range of environments, both ecologically and in terms of management and regulations. In most areas, the percentage of fires caused by flares was unknown but usually considered to be low to nonexistent. The Alliant Kilgore Flares Company develops and produces infrared countermeasure flares, and a wide spectrum of pyrotechnic devices for the U. It also makes pyrotechnics for various commercial activities.
Kilgore is the world's leading supplier of infrared countermeasure products. Kilgore is currently manufacturing an Israeli flare design under a Foreign Military Funding contract. Kilgore manufactured over six million infrared flares during the s. Kilgore has patented a variety of advanced countermeasure designs. The ALE has been installed in more than 15 aircraft types for the U.
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