[Music]
SARAH WOODS: So this is the FCDP.
It's a fast cloud droplet profiler.
And basically it'll sit inverted and it sits
underneath the plane so it's exposed to the air.
and there's electronics,
and a data acquisition system on here
as well as optics and a laser.
And the laser comes out one arm
and there's receiving optics on the other arm,
so the laser goes across this sampling volume.
And when a particle passes through there,
the light scatters, so we can count
how many particles we see,
cloud droplets.
And, based on the way the light scatters,
we can also size those particles.
NICK KRAUSE: Particles intersect the laser beam
and that creates a voltage difference
on our detectors.
And then the detectors analyze the signal
to determine how big the particles are
of the scattered light from the laser.
SARAH WOODS: This one sizes particles
in the range of 1 to 15 micrometers in size.
So cloud droplets and ice particles.
And later on, they'll be putting
another instrument on the aircraft,
the "Hawkeye",
which will measure particles and size particles
and also image particles over a wider range,
from the size of the FCDP
all the way up to a few millimeters in size.
[Music]
So here are some simple measurements
from the FCDP from a test flight over Colorado.
The red curve shows measurements from the FCDP,
the others are from another instrument.
But showing the concentration of the particles
over different size ranges.
So this information,
this is a time series of the same thing.
This is useful for the pilots or the scientists.
They can be looking at the data in real time
and know whether we're flying through clouds,
whether or not we're flying through clouds...
They can maybe know...
If they fly through the cloud at different altitudes,
they can take a profile of a cloud
and know if they want to sample in on a cloud.
They might need to go a little higher, a little lower...
Kind of helps them direct where they might need to go
and know what size of particles
they're flying through.
[Music]