Cyberflight Into The Eye of a Hurricane

Hurricane Hunter

Join Us for a Virtual Storm Flight

Welcome to the Hurricane Hunters!!! So you think you'd like to fly into a hurricane, huh? Well, virtual reality can only give you so much of the experience. We can't simulate the roller coaster ride but we can show you the ropes and take you along on a cyberflight into a storm.

The National Hurricane Center in Miami, FL monitors the tropical Atlantic and eastern Pacific for signs of the development of tropical systems. But over the open ocean, satellites, which is mostly all they have to work with, can only tell them so much.

So when an area of disturbed weather develops and they think it might become more than just a cluster of thunderstorms, they task the 53rd Weather Reconnaissance Squadron, the Hurricane Hunters, to fly into the disturbance and investigate.

The area of responsiblity for the Hurricane Hunters is from 55 degrees west in the mid-Atlantic to Hawaii in the Pacific. That's a lot of ground to cover and includes the western Atlantic, the Caribbean, the Gulf of Mexico, and the eastern Pacific. And there have been occasions when we have been spread across all of those regions at one time. Once a system does develop into a tropical storm or hurricane, we continue around-the-clock flights into the storm until it is no longer a threat to land or it makes landfall.

The NHC issues a tasking to the Hurricane Hunters in the form of the Tropical Storm Plan of the Day or POD as we call it. When the POD shows a tasking, our flight schedulers start assigning crew members to the flight and put them "in the bag" which means they are put into the required 12 hour crew rest period before the flight. Three hours before the scheduled takeoff, the crew shows up to prepare for the flight.

You're just in time... head across the hall to our auditorium, and join the crew for the pre-mission briefing.

Cyberflight Preflight Briefing

"Good morning. I am Captain Lance Oakland, your Supervisor of Flying for this mission. You're tasked to fly three fixes on Hurricane Dennis this morning! Your primary aircraft is 5301 on parking spot 14 with 52,000 pounds of fuel on board.

The crew that's out there right now just called and said they only had a few bumps all night, but the storm looks like its winding up and getting stronger. At the back of the room, we have a visitor from the Web who will be flying along with you on this mission. Have a safe flight!"

Cyberflight Flight Planning

The navigator carefully plots the position of the storm, which the weather officer just got from the National Hurricane Center. The storm is expected to be at 25 degrees north, and 90 degrees west, in the Gulf of Mexico, heading north-northeast towards the Florida panhandle.

Hope you packed a bag, because the way this thing is moving, we probably won't be coming back to Keesler Air Force Base tonight!

The pilots and the navigator prepare and file their flight plan and check the weather enroute.

Let's go out with the weather reconnaissance loadmaster and check out the plane.

Cyberflight Preflight Inspection

You step out onto the flight line, and pause to catch your breath: it's a typical summer day on the Mississippi Gulf Coast. You see only three airplanes parked on the ramp, and your escort explains that of the ten aircraft owned by the 53rd WRS, one is flying Dennis right now, and six have evacuated out of Dennis's way. The others will evacuate later this evening.

This is the aircraft that will take you on a very unusual ride. Your escort explains that its really "just thousands of spare parts flying in formation".

Was this supposed to be a comforting idea? But it's time to look at these parts, in the preflight inspection. We'll make sure she's ready to fly!

This airplane sure looks big when you get this close! As you follow the loadmaster on his rounds, he explains this is actually the smallest cargo airplane in the US Air Force today, but is often the one you see on television, delivering supplies to disaster areas. It can land almost anywhere.

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prefl

While the crew chiefs stand by in case any minor adjustments need to be made to our flying machine, the loadmaster even checks the exit lights. It's reassuring so many eyes have looked over the aircraft we're going to fly.

You immediately notice that the "Herc" is not built for comfort--it's a real workhorse. There are bundles of wires, cables and ducts running the length of the ceiling. The loadmaster will show you to your seat in the back of the airplane.

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Cyberflight Taxi and Takeoff

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The loadmaster has finished the aircraft preflight, and all systems are GO! So put in your earplugs as we start the engines. These engines are powerful and a lot louder than any commercial plane you might have ridden on before.

The loadmaster stands outside the aircraft during engine start to watch for flames, smoke, or any fluids spewing out of the engine. Scared yet?

This is your last chance to change your mind!

"Teal Four One, Keesler Tower. Winds 180 at 5, altimeter 29.95. cleared for takeoff runway two one. Climb and maintain two thousand, runway heading."

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The airplane is very heavy with a full load of fuel, so we'll have to use most of the mile-long runway. Brace yourself: the engines are running at full power, so as soon as the pilot releases the brakes, the plane will leap forward.

Rolling.... rolling... picking up speed... there's 100 mph... rotation...we're off! For another adventure into the most dangerous weather in the world.

Cyberflight Entoute to the Storm

As we fly over the Gulf of Mexico toward Dennis, the weather is beautiful! It's an odd feeling, knowing that what awaits us is quite different.

In Pilot Training, we were always told to stay far, far away from thunderstorms, now they want us to go right through them. We remind ourselves that we all volunteered for this job!

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Hurricane Dennis is nearly 300 miles away, so it will take only an hour and a half for us to get there. Let's tour the plane!
As you walk forward in the cargo compartment of this rather large plane, you find two very specialized equipment pallets at the front of the compartment.

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The On the left side of the cargo compartment is the ARWO (Aerial Reconnaissance Weather Officer) and the equipment that the ARWO uses to record flight level data from the aircraft's weather instruments as well as the satellite transceiver to communicate our data to the Hurricane Center.

A recent addition to the ARWO's arsenal of weather equipment is the SFMR (stepped frequency microwave radiometer) that allows us to sample wind speed at the ocean surface as we fly along above the ocean at 5,000 or 10,000 feet.

From here the ARWO is able to monitor the data, guide the pilots to the center of the storm using the wind speed and direction outside the aircraft, and make the fix when we pass through the center of the storm.

On the right side of the cargo compartment you'll find the weather reconnaissance loadmaster along with the equipment used to launch a dropsonde out of the aircraft, collect data transmitted back to the airplane from it, analyze and format the data, and send it to the ARWO for transmission to NHC.

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The dropsonde is a small weather instrument that sends temperature, humidity, barometric pressure, wind speed, wind direction, and position back to the aircraft twice each second during its 2500 foot per minute descent to the ocean surface.

This instrument allows us to collect important information about a storm such as maximum winds in the eyewall and surface pressure at the center of the storm.

nav

As you climb the stairs to the flight deck you find the navigator at the back of the cockpit. The navigators job is two-fold in a tropical storm mission.

The first, as you might well imagine, is to plot our course to and from the storm as well as plot our alpha pattern (see below) as we make multiple passes through the center of the storm.

The second job of the navigator is to help keep us all alive by monitoring the radar, keeping us clear of any severe thunderstorm cells and severe turbulence, and having an escape vector handy at all times in the even that the pilots feel we're in weather too heavy to safely navigate.

An "alpha pattern" is the flight path we typically follow as we collect data in a tropical storm.
To help you visualize what an "alpha pattern" looks like, think of cutting a diagonal across the storm, 105 nautical miles on either side of the eye.

Then, it's a simple case of always making left turns, so the aircraft doesn't have to fight the winds that are swirling counter-clockwise. Notice that after two passes through the eye (fixes), the winds in all four quadrants have been measured. At this point, the plane would typically continue the alpha pattern, making two more fixes before heading home.

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pilots

At the front of the cockpit sits our two pilots. The difficult task of flying a large 4 engine cargo aircraft into weather that every pilot is taught to avoid at all costs falls upon these two crew members.

While we all work as a team to accomplish the mission, it's the skill of these two people that gets us there and back safely.

As you look out the front windshield at the clouds thickening ahead of the airplane, the loadmaster comes up to let you know we are about to enter the storm.

You head back to the cargo compartment to take your seat, wondering if coming along on this ride was such a good idea after all!

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Cyberflight Into the Eye

Over your headset you hear the pilot talking.

"Attention to storm briefing, crew. Things are about to get busy, so please minimize chatter. The navigator will be directing the aircraft until we get close to the eye, then Weather will take us in from there, with the Nav backing him up.

Copilot, guard the autopilot, and kick it off if we get into severe turbulence. We're about to start our descent to 10,000 feet. Loadmaster, please make sure our passenger is belted in and the cargo compartment is secure.

We don't want anything flying around back there! Weather, your briefing..."

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Over your headset you hear the pilot talking.

"Attention to storm briefing, crew. Things are about to get busy, so please minimize chatter. The navigator will be directing the aircraft until we get close to the eye, then Weather will take us in from there, with the Nav backing him up. Copilot, guard the autopilot, and kick it off if we get into severe turbulence. We're about to start our descent to 10,000 feet.

Loadmaster, please make sure our passenger is belted in and the cargo compartment is secure. We don't want anything flying around back there! Weather, your briefing..."

As you take your seat, the loadmaster comes to you to ensure that you are buckled in. She tells you it's about to get bumpy and hands you an airsick bag.

You hear her yell over the drone of the engines that most people don't need them but don't be embarrassed to use it if needed. Then she sets off about her work tying down anything lose in the cargo compartment. It's obvious she isn't preparing for a normal flight.

Meanwhile over the headsets you hear the ARWO, "Ok crew, Dennis seems to have slowed down a bit. NHC has adjusted our first fix 30 nautical miles south of the expected fix position. Navigator, you'll need to adjust the flight plan accordingly.

The last crew reported a minimum pressure of 962 millibars and maximum winds of 120 miles per hour making it a category two hurricane. They didn't report any bad bumps but NHC says the storm has shown signs of intensifying since then so we could have a cat 3. Navigator, your briefing".

You hear the briefing continue as the crew prepares to enter the storm. Then the plane begins its descent to 10,000 feet from the 24,000 foot cruise altitude and slows to 180 knots. Outside the aircraft you can tell that it's getting darker as the clouds get thicker.

Once safely at 10,000 feet, you're allowed out of your seat to look out the windows. The crew is busy monitoring the weather instruments, the radar, and looking out the window.

We're now 105 nautical miles from the predicted center of Hurricane Dennis and the plane begins a turn inbound toward the eye of the storm. The weather officer switches on the High Density Data, which means the airplane is collecting position and weather data every 30 seconds.

You look over his shoulder at his computer screen, but it just looks like a bewildering mess of numbers--until he explains how to decode it. Each page of numbers is zapped through a satellite link directly to the computers at the National Hurricane Center, and eagerly studied by the forecasters to see how large and how strong the storm is.

Now the real fun begins. The weather officer looks down at the churning seas below, and estimates the strength of the wind by how the water looks. White caps, patches of foam, spray: each hint at the power of the furious winds spiraling around this dangerous hurricane.

The navigator asks the pilots to swerve around a particularly nasty thunderstorm--no need to tempt fate at this stage of the game

dennis_radar

The navigator calls out that he sees the eye on radar. There are spiral bands of thunderstorms wrapping around a bright ring surrounding a clear spot on radar.

The bright ring is called the "eyewall" and is a solid ring of thunderstorms, containing the most violent weather in the storm.

It looks so small on the scope, but the ARWO assures you the tiny clear spot is 15 miles across, and the eyewall is 20 miles away!

"We're five miles from the eyewall." announces the navigator. Heavy rain begins to pelt the airplane, and sheets of water wash over the windows.

It gets darker, and turbulence begins to rock the plane. It's hard to walk back to your seat, but the loadmaster assures, "You ain't seen nothing yet!"

rain

"We're about to penetrate the eyewall; everyone strap in," commands the pilot. Just as you finish snapping your seatbelt closed, you're thrown violently against your straps. You get that "funny feeling" in your stomach as the plane free-falls 1000 feet, and you feel nearly weightless for a moment.

Through the deafening noise of surging propellers and pounding rain, you think you hear someone yell "Yee-hah!" Suddenly, the plane seems to buck in every direction at once, and a brief flash of lightning breaks through the darkness so close you can actually hear the thunder over the noise of the plane.

eyewall

After what seems like an eternity (was it really just three minutes?), the dark grey clouds outside the window begin to brighten, and suddenly blinding white light stings your eyes.

The hiss of heavy rain shuts off in the same instant. One or two sharp bumps, and the plane flies smoothly again.
You're not sure you've ever felt your heart pound so hard, but you survived...you're in the eye!

As your eyes adjust to the glare of sunlight,you gaze out at one of the most awesome scenes in nature: the "stadium effect" inside the eye. A solid wall of clouds circles around the WC-130, as though you are floating in a giant football stadium made of clouds.

You are inside a giant well that opens up miles above your head into a bright, blue sky. Congratulations...you've just joined an exclusive group: those few people who have entered the eye of a hurricane

There's no time to relax; the real work lies ahead. "We're almost there," declares the weather officer. "I see a calm spot ahead on the water," confirms the pilot.

You notice that the air conditioning doesn't seem to be working so well anymore, then you remember hearing that the temperature is warmer inside the eye.

Meanwhile, at the back of the plane, the loadmaster is busy loading the dropsonde into its launch tube, getting ready to drop the instrument into the exact center of Dennis' eye.

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acft_eye

The weather officer watches intently as the wind speed dies off, then suddenly the wind shifts; instead of coming from the left, it's now coming from the right.

"Fix it here!" shouts the weather officer, and the navigator marks our precise position--the exact center of the eye. There's a "der-chunk" sound as the dropsonde ejects from the plane with a push of a button.

"Sonde away," announces the loadmaster. Everyone is working furiously as the ominous wall cloud looms ever closer to our "tiny" airplane.
The navigator plots the position and compares it to the last fix from the Hurricane Hunter airplane that left Dennis two and a half hours ago.

"Dennis is moving 340 degrees (north-northwest) at 7 knots (8 mph)," he informs the crew. The weather officer finishes typing up the last details on the Vortex Data Message, then with a few keystrokes, the critical information is sent via satellite to the National Hurricane Center.

We punch back into the eyewall and plunge immediately into the darkness, rain, and turbulent air that we had left only a few moments ago. But somehow it doesn't seem so bad this time (now that you're a veteran Hurricane Hunter!).

The dropsonde finally hits the water, and the loadmaster codes up the information. His report: the sea-level pressure is 942 millibars. This surprises the crew, since the last fix reported it as 962 millibars!

The weather officer explains that a five millibar drop can be significant...but this is amazing!!! The news electrifies the forecasters in Miami; Dennis is really intensifying!

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eye_pict

You fly another 105 nautical miles away from the eye to measure the extent of damaging winds in that quadrant of the storm, then turn to intercept the next inbound leg in the big X-shaped alpha pattern crisscrossing the storm.

Less than two hours after the last time you penetrated the eye, you're there again! In fact, you'll penetrate the eye a total of four times on this flight, until the next Hurricane Hunter airplane is on its way to take over.

Cyberflight Homeward Bound

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During the entire six hours you spend inside the storm, the hurricane specialists at the National Hurricane Center in Miami are flooded with weather data measured automatically by the aircraft every 30 seconds. Plugging this information into the NHC's computers can improve the forecast by up to 30%!

The hurricane specialists are especially astounded by the dropwindsonde data, which reveals the central pressure dropped 37 millibars in 24 hours.

Their new warnings prompt civil defense and other emergency managers across the Florida panhandle to speed up evacuations.

Thankfully, Dennis weakened significantly before making landfall near Pensacola, Florida. She still caused $1.15 billion dollars in damage and three U.S. deaths. Even "minimal" hurricanes can wreak incredible destruction and must be taken seriously.

Thanks for surviving your "Cyberflight Into the Eye"! We hope you enjoyed the trip--if you did, please tell your friends. We hope you'll accept this memento of your flight, a cyber-patch!!!

Just point to the patch, "right-click" your mouse, save the gif file, and display it proudly on your computer...you earned it!

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