Llwas - How Does It Work?

Sat Feb 17, 2001 8:36 am

Does anybody know how LLWAS (low level wind shear alerting system) works? How comes the info into the cockpit?

RE: Llwas - How Does It Work?

Sat Feb 17, 2001 11:59 am

Windshear has its greatest effects at low altitudes.

A Low Level Windshear Alert System (LLWAS) basically takes surface
wind measurements at multiple anemometer sensors to detect
windshear and triangulates and pairs the readings. The LLWAS
algorithm uses the filtered wind field values to estimate the true
wind field divergence. This wind and shear information is sent to air traffic controllers in digital or graphic form. LLWAS systems
track and predict windshear in the approach and departure paths
of an airport which allows controllers to anticipate the need to
configure runways before wind shifts occur. LLWAS is designed to issue a Windshear Alert when it estimates an intensity of between 15 and 30 knots and a Microburst Alert when it estimates an intensity in excess of 30 knots.

RE: Llwas - How Does It Work?

Sun Feb 18, 2001 12:54 am

LLWAS alert is given to pilots by the controller via voice communication. The info given are the centerfield wind and the boundary wind.

To have more sophisticated alerts, airports need to have TDWR (Terminal Doppler Weather Radar) , integrated with LLWAS...still done by voice  Smile/happy/getting dizzy. Of course transports have their own windshear detection onboard but that's another story.


Who is online

Users browsing this forum: No registered users and 3 guests

Popular Searches On

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos