Bird Strike Testing

[pjcoach]

I am looking for a quality testing house that performs bird strike testing. Can anyone provide some contacts?

 

[aviat]

Learjet has a facility in Wichita KS, but I don't know if they do outside work. You could try them.

 

[FredGarvin]

We have dealt with the folks at University of Dayton Research Institute (experimental and applied mechanics div)for some aspects of our own bird tests. You might want to try them.

 

[techmaximus]

Kind of off topic but did you see that episode of Myth Busters on the Discovery Channel where they used an air cannon to fire frozen and thawed chickens at an aircraft windscreen. The idea was to either prove or disprove that story about the aircraft engineers who mistakenly fired frozen chickens at an aircraft windscreen. The guys on the show claimed to have “busted” the myth by demonstrating that regardless of frozen or thawed, the energy at impact of the bird on the windscreen was the same and the same damage resulted either way.

SCET - Techmaximus

 

[lbell]

Check with Southwest Research Institute in San Antonio.

 

[pjcoach]

Thanks, all, for your help. I'll make some calls and see what's out there.

 

[EngJW]

I didn't see the show but it seems like a soft birdie would absorb more of the impact, just like crush zones on a car. The kinetic energy would be the same (same mass and velocity) but the rate of change of momentum (=impulse? I forgot) would be less. Then again, maybe the difference is not enough to affect the outcome of the test, or the windshield is strong enough to withstand either situation.

 

[aerodog]

techmaximus/jlwoodward

the myth buster vs the frozen chicken has its own thread.

check my 01-25-05 post on the same suject.

 

[aerodog]

Like a lot of qualification testing, aircraft bird shot testing is arbitrary.

The bird is to weigh 4 pounds and the velocity at impact is the max speed the airplane can fly below 14,000 ft.

So all this assumes so long as the bird's weight does not exceed 4 pounds and is not flying above 14,000 ft, the crew is safe.

Nor does the criteria take into account the direction the bird might be flying at impact.

Let's assume the airplane was qualified to 300 knots. If the bird is flying towards the airplane at 20 knots, the impact velocity is 320 knots. The energy at impact is proportional to the square of the velocity, so the energy at impact would be about 14% higher than the test impact energy level.

 

[awparran]

I saw the show and there was no difference in a frozen or thawed bird. They both did the same amount of damage.

When fired into a flat plate, again there was very little if any difference in the amount of impact.

 

[awparran]

When fired into a flat plate, again there was very little if any difference in the amount of impact damage.

Both birds shattered into a zillion pieces.

 

[aerodog]

Aircraft windshields are not flat panels perpendicular to the airstream.

When the bird impacts the windshield, only part of the energy needs to be absorbed by the windscreen. Most of the energy gets carried off with the remains that are deflected off to the side or over the top. That is why it is important for the bird to be freshly killed and still relatively soft.

To qualify a windshield, it takes several shots at various points considered most vulnerable. Aircraft centerline shots can be the most difficult to pass.

And if you are imagining a bunch of feathers, blood and guts,it does not work that way. At the impact area, it looks like it was painted with a coarse gray paint. The rest is pulversized and not identifiable.

 

[Engdyn18]

Yes, Southwest Research Institute in San Antonio, TX has a section within their Engineering Dynamics Dept. that conducts ASTM Bird Strike and Hail Stone Impact Testing on a variety of targets over a wide range of impact velocities. Try "Southwest Research Institute" on Google then look for Division 18, Mechanical & Materials Engineering Division for points of contact.