Ice detector

Ice detector

An ice detector is an optical transducer probe available for aviation purposes. It has no moving parts, is completely solid and its principle of operation is entirely optical. Intrusive to the airstream and hermetically sealed, it uses un-collimated light to monitor the opacity and optical refractive index of the substance on the probe. It is de-sensitized to ignore a film of water.

The device works as a combined optical spectrometer and optical switch. A change in opacity registers as rime ice. A change in refractive index registers as clear ice. Optical components are made of acrylic glass, which is the material used for aircraft windshields. The wavelength of the transducer's excitation light is not visible to the human eye so as not to be mistaken for any kind of navigational running light.

Installation

Optical ice detectors can be installed on any type of air vehicle with enough air speed to keep water from accumulating on the optics, such as rotorcraft, general aviation aircraft and unmanned aerial vehicles. They can be embedded into host aerospace systems such as an altimeter, antenna, anti-icing system, flight data recorder, jet engine inlet, pitot tube, stall warning indicator or weather system.

Optical ice detectors operate on 3.3 V DC at 100 mA. Installation requires the probe to be mounted in the airstream beyond the boundary layer, and in a location easily accessible to the pilot for occasional cleaning with a cotton swab and isopropyl alcohol.

Operation

The device works as a rudimentary go/no-go ice indicator or as an icing rate indicator for pilots who may have inadvertently entered icing domains.

Electronic signal-level comparators sense the transducer's output and activate LEDs to indicate relative icing rates to the pilot. The pilot can then judge the rate of ice accumulation and make a piloting decision. Once the aircraft has left the icing region, the ice either ablates or melts and blows away. The icing rate display sequence then reverses itself.

Transducer probe de-icing can be hastened by incorporating turns of resistance wire and dissipating a few watts into the probe, which weighs ¼ ounce. This resets the transducer in anticipation of the next icing event.

Optical ice detectors offer substantial adjustment range of drive level and returned signal amplification. Thus, they can be applied to operate in a wide variety of applications and sensitivities, down to 0.001" of ice.

Testing

Testing at NASA Glenn Icing Research Tunnel in Cleveland, Ohio, has verified the performance of optical ice detectors.Fact|date=February 2007reference: NASA Lewis (Glenn) video document D040 dated 23 September, 1997, range time = 18:43:37 hours

Other types

Other types of ice detectors for aircraft include:

* acoustic - registers changes in the sound wavelength when icing occurs
* nuclear - registers changes in emission level when icing occurs between source of radiation and the sensor


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • Ice cube (disambiguation) — Ice cube can mean several things:* Ice cube a chunk of frozen water in the shape of a cube. * Ice Cube an American rapper, actor and film director. * IceCube Neutrino Detector. * A nickname for the Beijing National Aquatics Center, the swimming… …   Wikipedia

  • Neutrino detector — The Sudbury Neutrino Observatory, a 12 meter sphere filled with heavy water surrounded by light detectors located 2000 meters below the ground in Sudbury, Ontario, Canada. A neutrino detector is a physics apparatus designed to study neutrinos.… …   Wikipedia

  • Antarctic Muon And Neutrino Detector Array — The Antarctic Muon And Neutrino Detector Array (AMANDA) is a neutrino telescope located beneath the Amundsen Scott South Pole Station. It consists of optical modules, each containing one photomultiplier tube, sunk in Antarctic ice cap at a depth… …   Wikipedia

  • Antarctic Muon And Neutrino Detector Array — L Antarctic Muon and Neutrino Detector Array (AMANDA, Réseau antarctique de détecteurs de muons et de neutrinos) est un télescope à neutrinos situé sous le Pôle Sud. Il va être remplacé et incorporé dans le projet IceCube. Sommaire 1 Historique 2 …   Wikipédia en Français

  • Antarctic muon and neutrino detector array — L Antarctic Muon and Neutrino Detector Array (AMANDA, Réseau antarctique de détecteurs de muons et de neutrinos) est un télescope à neutrinos situé sous le Pôle Sud. Il va être remplacé et incorporé dans le projet IceCube. Sommaire 1 Historique 2 …   Wikipédia en Français

  • Antartic Muon and Neutrino Detector — Antarctic Muon and Neutrino Detector Array L Antarctic Muon and Neutrino Detector Array (AMANDA, Réseau antarctique de détecteurs de muons et de neutrinos) est un télescope à neutrinos situé sous le Pôle Sud. Il va être remplacé et incorporé dans …   Wikipédia en Français

  • Antartic Muon and Neutrino Detector Array — Antarctic Muon and Neutrino Detector Array L Antarctic Muon and Neutrino Detector Array (AMANDA, Réseau antarctique de détecteurs de muons et de neutrinos) est un télescope à neutrinos situé sous le Pôle Sud. Il va être remplacé et incorporé dans …   Wikipédia en Français

  • Radio Ice Cerenkov Experiment — (RICE) is an experiment designed to detect the Cherenkov emission in the radio regime of the electromagnetic spectrum from the interaction of high energy neutrinos (greater than 1 PeV) with the Antarctic ice cap. The goals of this experiment are… …   Wikipedia

  • Antarctic Muon and Neutrino Detector Array — Pour les articles homonymes, voir Amanda. L Antarctic Muon and Neutrino Detector Array (AMANDA, Réseau antarctique de détecteurs de muons et de neutrinos) est un télescope à neutrinos situé sous le Pôle Sud. Il va être remplacé et incorporé dans… …   Wikipédia en Français

  • Сигнализатор обледенения — устройство, предназначенное для непрерывного измерения интенсивности обледенения технических средств, с выдачей информации оператору и в автоматическую систему противообледенения. Применяются преимущественно для контроля обледенения летательных… …   Википедия

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”