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Good science boils down to making as many high-quality observations as possible

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and then analyzing and interpreting them.

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At NASA Langley Research Center in Hampton, Virginia,

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a five-year research program called the Joint Runway Friction Measurement Program is underway.

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This international effort is investigating aircraft losing traction on icy runways.

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This icing research program is having some groovy spinoffs.

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Let's meet with Tom Yeager and learn more about runaway runways.

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Thanks, Shelley.

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I'm standing here this morning in our aircraft landing dynamics facility shop area.

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Behind me you can see one of our test carriages.

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We've got a display here of a landing gear system that we're looking at to evaluate

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from a standpoint of reducing the loads going into the fuselage.

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On my right here is a display showing some of the work that we've done

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to support the shuttle tire program that got started in the mid-'70s

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and has been quite successful since then.

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We've done several modifications to the runway down there based on research data

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that we obtained here at our aircraft landing dynamics facility in Hampton, Virginia.

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We've also done work in modifying the tire design and the brake unit

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that's used on the shuttle that's being flown later on this month from Kennedy Space Center.

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We do a lot of work looking at aircraft tread design, how the grooves are positioned,

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and minimize the hydroplaning potential that can occur during aircraft landing

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and takeoff operations on wet runways.

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You're viewing a typical aircraft landing gear tire touching down on a contaminated or ice-covered surface.

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And due to the reduced friction capability between the tire and the ice,

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it takes a considerably long time for this tire to spin up to a speed

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that's equal to the forward motion of the airplane.

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We're currently involved in the fourth year of a five-year program

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with a partnership with the FAA, Transport Canada, the National Research Council up in Ottawa,

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the National Defense Department out of Winnipeg,

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as well as several aviation organizations supporting this activity

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where we're evaluating aircraft braking performance under winter conditions.

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These conditions include snow, ice, slush, and water.

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And to date, the majority of the tests have been taking place in North Bay, Ontario,

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which is about two and a half hours north of Toronto.

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We've evaluated braking performance of a Falcon 20, a de Havilland Dash 8 airplane,

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an FAA Boeing 727 airplane, and a NASA Boeing 737 airplane.

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Coming up in this program, you'll be involved in a classroom experiment

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that will give you a better idea of how the coefficient of friction influences the motion of two objects,

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for example, pavements and tires.

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In our work here at the track facility, we've identified the fact that the higher the friction coefficient,

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the shorter the stopping distance is for an airplane operating on a runway

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and the less chance he has of going off either the side or the end of the runway.

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Some of the equations that determine this behavior of vehicles operating on pavement surfaces

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will be explained to you in the classroom experiment.

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And I want to wish all of you good luck in conducting that experiment.