February 2008 Feature Story:
Hunting Hugo

Story by Dr. Jeff Masters, Chief Meteorologist, The Weather Underground, Inc.

Take-off
The familiar roar of the engines shake “NOAA 42”, a P-3 Orion, as the thrust of take-off pushes me back into my seat. The lush greenery of Barbados rushes past then falls away as the big plane lumbers into the air. We cross the coast, the spectacular turquoise-blue waters of the Caribbean sparkling up at us in the intense tropical sunshine. The tranquility and beauty of the scene make it difficult to believe a huge, destructive hurricane lurks a mere hour’s flight away.

Lowell Genzlinger is aircraft commander, a veteran of 249 hurricane eye penetrations. There is no better pilot in the business. Co-pilot is Gerry McKim, a relative newcomer to hurricane flying, but a Navy P-3 pilot for 20 years before coming to NOAA. This is his second year flying hurricanes. He is working towards becoming an aircraft commander, and will be the pilot during today’s eye penetrations. Rounding out the flight crew is flight engineer Steve Wade, also in just his second year of hurricane flying. His job is to monitor engine performance, fuel consumption, and other critical aircraft functions.
We climb to 10,000 feet and level off, heading northeast.

I check the lower fuselage radar display. The bright reds and yellows of Hugo’s outermost spiral rain bands have already appeared. It is a huge storm, over 400 miles in diameter.

“Look at that radar presentation!” I exclaim over the intercom.

“Yeah, that’s a pretty good looking storm,” replies Frank Marks, lead scientist. “Looks like it has its act together.”

“Hey Jeff, what kind of track do you want?” interrupts Gerry, from the cockpit.

“Let’s go with a track of zero-seven-zero until we start getting near the outer spiral band,” I reply.

“Turning to zero-seven-zero!” says Gerry.

Gerry banks the airplane to bring us to a heading of oh-seven-oh degrees, and levels us out. I begin studying the lower fuselage radar display to gauge Hugo’s intensity and position in more detail.

I lean in close to my screen and study the radar display. Hugo has an impressive symmetry, with two major spiral bands and a 12-mile diameter eye — pretty tight by hurricane standards, and difficult to orbit inside should we get in trouble and need to stay in the eye. I’ve been in several other hurricanes with eyes this small, and both were rough, intense storms undergoing rapid deepening. Hugo may be doing the same. I look closely at the eyewall — a tight ring of bright orange and red echoes surrounding the eye. Checking the echo intensity scale at the side of the display, I find that the radar information looks consistent with this morning's satellite estimates of Hugo’s intensity — winds of 130 mph and a central pressure of 950 millibars, a strong category three storm on a scale of one to five. My examination of the radar display is fairly hurried, and I fail to notice that the strongest echoes from the radar display are off scale. Frank appears at my station, and I remove my headset to talk.

“Looks like an impressive storm!” He shouts above the noise of the four engines. “We need to do the mission at an altitude that’s low, but not so low that it’s real rough and we get bad radar data.”

“Well, Hugo’s definitely getting his act together,” I shout back. “Do you still want to try it at 1,500 feet?”

“Well, we got away with it in Hurricane Gabrielle last week, and Hugo looks like it’s about the same strength. Let’s try the first penetration at 1,500, and if it’s too rough, we’ll climb to 5,000,” he answers.

“OK, 1,500 it is!” I yell back. As Frank disappears back into the cockpit to take the chief scientist’s seat, I talk to the cockpit on the intercom. “They want to go in at 1,500 feet. How do you feel about that?” I sound and feel nervous about this choice.

“Fifteen hundred, hey?” the pilot responds. I can tell by his tone of voice he feels none too comfortable with this choice, either. “I’d be happier at 5,000.”

“Yeah, me too. But we got away with it last week in Gabrielle, and if it’s rough on the first penetration, we can do the rest of the mission at 5,000.”

“All right. We'll take her down to 1,500 and see how it goes. Here we go!”

Approaching the Storm
The big plane noses down into its descent. My stomach flutters from the brief sensation of weightlessness — and the knowledge that we are now only a few minutes away from our rendezvous with the eye of Hurricane Hugo, at 1,500 feet!

I look out my window, and watch the ocean grow closer. Powerful wind gusts of 40 to 50 mph drive crescent-shaped white-capped waves over the ocean surface. We cross over
several hurricane feeder bands — tall heaps of piled cumulus clouds arranged in picturesque lines that spiral into the eyewall. Ahead, the first major spiral band — an ominous dark mass of forbidding cumulonimbus clouds — blocks our path.

“OK, leveling out at 1,500 feet,” calls out Lowell. “We’re getting pretty close now, time to button things up.”

“SET CONDITION ONE!” Lowell’s voice crackles over the aircraft’s loudspeakers and intercom. Condition One requires all hands to return to their seats and prepare for turbulence. Throughout the airplane, the crew stashes away flight bags, clipboards, and other loose items that could turn into dangerous missiles in severe turbulence. I buckle my heavy-duty seat belt, but don’t bother with the shoulder harness. The turbulence in a spiral band is never too bad.

Twilight falls. Thick grey clouds engulf us. The winds jump to 85 mph. Minor turbulent wind gusts bounce and bump the aircraft, and a new sound joins the ever-present roar of the engines — the clatter of heavy rain lashing the fuselage.

Two minutes later, the sky lightens and the turbulence suddenly stops. We emerge from the spiral band into the clear. A typical spiral band penetration, no big deal. The wind has dropped to 50 mph, with a slight shift in direction. Good. With a wind this low between the spiral band and eyewall, it is unlikely that Hugo is more than a category three storm. I check the lower fuselage radar display again. Look at that eyewall! The glowing red donut of the eyewall is closer, only ten minutes away now, and much more impressive. I suppress an urge to call for a climb to 5,000 feet.

I adjust my radar display to zoom in on the eye. The bright oranges and reds of the eyewall lie before us, growing closer and more ominous with each sweep of the radar. The eyewall looks frightening, impenetrable, now just seven minutes away. I suppress another urge to chicken out and order a climb to 5,000 feet.

Three minutes from the eyewall, still time to order a climb to 5,000 feet. I check my wind readings. Winds are well below hurricane force — a mere 60 mph. Hugo may not even be a category three storm! I make my final decision not to order a climb to 5,000 feet. We’re going in at 1,500! I look out my window at the approaching eyewall, a tall dark wall of forbidding thunderstorm clouds. “Foolish mistake!” I imagine the threatening voice of Hurricane Hugo saying to me.

Into the Eyewall
We hit the eyewall. Darkness falls. Powerful gusts of winds tear at the aircraft, slamming us from side to side. Torrential rains hammer the airplane. Through my rain-streaked window, I watch the left wingtip flex down a meter, then up a meter, then down two meters through the gloomy dark-grey twilight. My stomach is clenched into a tight knot. The ride is choppy, uncomfortable.

I grab the computer console with both hands, trying to steady my vision on the blurred computer readouts. I don’t like what I see. The winds are rising too quickly, the pressure falling too fast. Hugo is far more powerful than expected. The aircraft lurches and bucks in severe turbulence.

Thirty seconds in, a minute and a half to go. The turbulence grows worse. Hugo is stronger than Emily. I am very concerned. We should not be at 1,500 feet! I fumble for the intercom switch, find it. “Winds are 135 mph, surface pressure 960 millibars,” I say. “Hugo’s at least a category 4.”

Frank breaks in. “Lowell, Jeff, this ride is way too rough! Let’s climb to 5,000 when we finish this penetration.”

“Roger!” is Lowell’s terse reply. Both he and Gerry must wrestle with the controls of the airplane. The turbulence is so violent that one pilot alone cannot stay in control. There is no possibility of climbing now; the pilots need the full power of the engines just to keep the airplane flying straight and level.

One minute in, one minute to go. The intercom goes silent as everyone hangs on and the pilots concentrate on getting us through the eyewall. I watch the winds and the track of the aircraft to ensure we are on course to the eye. Gerry does a great job fighting off the turbulence and keeping the airplane on track. I don’t need to order any course corrections. Winds are now 155 mph, still rising. Pressure 955 millibars, dropping fast. The turbulence grows extreme. Hugo is almost a category five hurricane.

A fierce updraft wrenches the airplane and slams us into our seats with twice the force of gravity. Seconds later, we dangle weightless as a stomach-wrenching downdraft slams us downward. Clipboards, headsets, and gear bags spill loose and slide across the cabin floor.

Another updraft, much stronger, grabs the aircraft. I regret forgetting to fasten my shoulder harness, as I struggle to keep from bashing into the computer console. Seconds later, a huge downdraft blasts us, hurling the loosened gear against walls and floor. Gerry and Lowell are barely in control of the aircraft. Grimly, I hang on to my console against the violent turbulence and watch the numbers. Sustained winds now 185 mph, gusting to 196 mph. Pressure plummeting, down to 930 millibars. Hugo is a category five hurricane, and we are in the eyewall at 1500 feet! One strong downdraft has the power to send us plunging into the ocean. We have no options other than to gut it out and make it to the eye, where we can climb to a safer altitude.

A minute and a half gone, half a minute to go. A colossal updraft seizes the airplane. A shower of loose gear flies through the cabin as the airplane lurches violently. Gerry fights the updraft off, keeps the airplane level and headed towards the eye. We’re almost there!

“Looks like it's lightening up out there!” Lowell’s relieved voice breaks the intense silence. Sure enough, the sky lightens, the clouds thin, the rain abates. We are at the edge of the eyewall. A big smile of jubilation erases my anxious frown. We got away with penetration of a category five storm at 1,500 feet.

Disaster
Then, disaster. Thick dark clouds suddenly envelop the aircraft. A titanic fist of wind, three times the force of gravity, smashes us. I am thrown into the computer console, bounce off, and for one terrifying instant find myself looking DOWN at a precipitous angle at Sean across the aisle from me.

A second massive jolt rocks the aircraft. Gear loosened by the previous turbulence flies about the inside the aircraft, bouncing off walls, ceiling, and crew members. Next to Terry Schricker, our 200-pound life raft breaks loose and hurtles into the ceiling. A third terrific blow, almost six times the force of gravity, staggers the airplane. Clipboards, flight bags, and headsets sail past my head as I am hurled into the console. Terrible thundering crashing sounds boom through the cabin; I hear crew members crying out. I scream inwardly. “This is what it feels like to die in battle”, I think. We are going down. The final moments of the five hurricane hunter missions that never returned must have been like this.

The aircraft lurches out of control into a hard right bank. We plunge towards the ocean, our number three engine in flames. Debris hangs from the number four engine.
The turbulence suddenly stops. The clouds part. The darkness lifts. We fall into the eye of Hurricane Hugo.

The Eye of Hugo
“WE’VE GOT FIRE COMING OUT OF NUMBER THREE!” Terry’s urgent cry shatters the stunned silence on the intercom.

“And I see something hanging from number four,” adds Sean, his voice sounding strangely calm.

For several eternal terrifying seconds, I watch the massive, white-frothed waves below us grow huge and close. I wait for impact, praying for survival. With two engines damaged, both on the same wing, I know that our odds are not good.

But my prayers are answered by the cool, professional reaction of the cockpit crew. Gerry snaps us up out of the right-rolling dive, a perilous 880 feet from the water. Steve Wade hits the kill switch on engine number three, and the 30-foot long flames shooting out of it die as the flow of fuel chokes off.

A dark mass of clouds lies directly ahead, seconds away. Is it the eyewall? Or merely harmless low scud in the eye? There is no time think, no time to plan the best flight path. We must turn now to avoid the clouds. If we hit the eyewall again at this altitude, the storm will surely kill us. We must stay in the eye.

“It’s clear to the right!” Lowell shouts out. Immediately, Gerry throws us into a hard right roll. I look at my radar display, and quickly compute our position. A right turn is the wrong choice! We popped into the eye off-center, on its right side, and now must trace out an almost impossibly tight four-mile diameter circle to stay in the eye. The dark clouds that Gerry turned us from were merely harmless low level scud in the eye. We should have turned left! It is too late to call for a course change, though. We are committed to this turn.

Tense seconds pass. I watch the wind speed indicator as the winds slowly increase — 30 mph, 40 mph, 50 mph. The eyewall grows closer, a huge ominous wall of seething dark clouds spinning past my window. Gerry has us banked over as far as he dares, at a 30-degree angle.

I can see only a blurred, white wall of clouds, frighteningly close, out my window. I lean out into the aisle to see the view out the cockpit window. The view is the same — a white wall of turbulent clouds spinning by at a dizzying speed. I see Frank standing up, craning his head towards the right upper window, straining to see where we are headed. “Keep on coming!” I hear him call out to the pilots. The left wingtip is now just a few hundred feet from the eyewall.

A fist of clouds protrudes out from the eyewall, blocking our path. We penetrate. Turbulence rocks the aircraft. The winds jump to 75 mph, hurricane force. We are in the eyewall. Gerry banks us even harder right, a 35-degree roll. We are dangerously close to stalling. An eternal few seconds later, we emerge into the eye again.

“Keep on coming!” I hear Frank say, once again.

Again, eyewall clouds grab at the airplane, shaking us with frightening turbulence. Another eternity later, we pop out in the clear as Gerry maneuvers us out of the clouds, keeping us barely within the eye. We are now fast approaching the deadly part of the eyewall where we originally entered the eye. Our turn is nearly complete.

“That’s it, you’ve got it!” I hear Frank exclaim.

Gerry relaxes the steep bank, and heads us into the center of the eye. A few seconds later, he puts us into a left roll that will keep us comfortably in the eye for as long as we want to circle. He brings the nose of the aircraft up, and we begin a steady spiraling climb. The immediate danger is past.

Awesome, Terrifying, Supernatural
I look out my window, and behold the eye of Hurricane Hugo in its full fury. It is awesome, terrifying, and supernatural. The eyewall, a towering prison of blinding-white, boiling, virulent clouds rings us on all sides. We are so low that I can see beneath the ragged bottom edge of the eyewall clouds, where Hugo’s 160-mph surface winds whip the ocean surface into a greenish-white blur. Below us, the ocean churns in a frightening chaotic frenzy of colliding 50-foot high waves.

“You are not welcome here,” I imagine the fearsome voice of Hurricane Hugo saying, “and I may well destroy you for your insolence, for you must penetrate my eyewall one more time to escape.” I angrily curse myself for failing my primary duty, ensuring the safety of the mission from a meteorological perspective. My job today is done. It is now up to Gerry and Lowell to get us out of the crisis I got us into.

Lowell’s voice comes on the intercom: “OK, we’re going to circle in the eye as long as we can and climb to our maximum altitude before we attempt to punch out through the eyewall. All right,” Lowell continues, “Number three engine is shut down, and it looks like we got the fire fully extinguished. Can anyone back there take a good look at number four and tell us what it looks like?”

Across the aisle from me, Sean looks out his window and responds, “It looks like it might be a dislodged de-icing boot.”

“Well, let’s hope it doesn’t tear off and get caught in the propeller,” says Lowell. “We need to lighten the plane up as much as possible to gain altitude, so we’ll be dumping fuel. I’ll want all communications equipment and electrical gear that could cause a spark powered off.”

A new voice, Dave Turner, commander of NOAA 43, breaks in: “NOAA 42, this is NOAA 43, come in.”

“Dave, we can’t talk now!” cries Lowell. “We’ve got a serious emergency on board! We’re in the eye with only three engines, have damage to another, and are preparing to dump fuel.”

“Oh my!” says Dave. There is a pause as the seriousness of our situation sinks in. “Okay, we’ll come into the eye and look out for you. I’ll also advise the Air Force airplane of your situation; they are closer to the eye than we are.”

“Thanks Dave, we’re going to dump fuel now, so this will be our last communication for about 15 minutes. We’ll give you a call when we’re finished. Please advise Miami of our situation. Four-two out.”

“Good luck, four-two! Four-three out.”

I leave my seat, and step into the cockpit to confer with Lowell. Pete Black is there, too.

“So what’s the plan, Lowell?” I ask.

“We’ve got to stay in the eye and lighten the aircraft up as much as possible,” Lowell responds. He does not look up from the controls as he talks. He sounds very worried, but is focused, in command. I look across the cockpit at Gerry. He is concentrating intensely on flying, keeping the airplane safely within the eye and steadily climbing.

“The cockpit G-meter shows we took five and half G’s up and three and half G’s down,” continues Lowell, now sounding really concerned. “The P-3 is only rated to plus three and minus two G’s, so we may have some serious structural damage. We’ll have to climb as high as we can and find a part of the eyewall with minimum turbulence to exit through.”

“Five and half G’s!” I exclaim, looking at Pete in amazement and trepidation. No hurricane hunter aircraft has ever taken more than three G’s. We are lucky to be alive.

Deadly scenarios
I return to my seat and look out at the eyewall of Hugo again. It is awesome, fearsome, and impenetrable. I feel trapped, helpless, and despondent. To cheer myself up, I snap a series of photographs of the eyewall.

The flow of fuel out the fuel dumping pipe slows to a trickle, then stops. I hear Gerry’s voice over the intercom. “Okay, we’re all done dumping fuel. You can turn back on any equipment you turned off.”

Terry and Alan turn the communications equipment back on, and Lowell immediately contacts the TEAL 57, the Air Force C-130 reconnaissance airplane sent into the storm by the National Hurricane Center to provide information on Hugo’s position and intensity.

“NOAA 42, this is TEAL 57,” radios the voice of Lieutenant Commander Terry Self, aircraft commander of TEAL 57, and veteran of 10 years of hurricane flying. “NOAA 43 has advised us of your situation. Can you give us your position and altitude, and update us on your status?”

“Roger,” relies Lowell. “We are circling the eye in a left orbit at 5,000 feet. We’ve lost the number three engine, and have damage to the number four engine. We’d like you to come fly by and take a look at our number four engine, and inspect us for any other damage we can’t see.”

“Sure thing, NOAA 42,” says Self. “We’ll penetrate the west eyewall and come down and have a look at you. TEAL 57 out.”

“Roger. Thanks, TEAL 57! NOAA 42 out.”

The next five minutes we wait anxiously for the Air Force airplane to penetrate the eyewall. They are definitely sticking their necks out for us — I have never heard of an Air Force airplane penetrating an intense hurricane at an altitude less than 10,000 feet. Only the foolish NOAA airplanes risk going in hurricanes at altitudes below 10,000 feet! Finally, the radio crackles back to life with the voice of Commander Self.

“NOAA 42, we are in the eye. We got a terrific pounding going through the west eyewall coming in, but are still in one piece!”

My heart sinks at this news. What chance did we have of making it through the eyewall with only three engines?

“We’ll come take a look at you now,” continues Self. “What is your current position and heading?”

Lowell gives him our current position and heading, and the two aircraft commanders proceed to coordinate a close fly-by in the eye of Hugo. Fly-bys are dangerous operations in the best of conditions; great caution must be exercised to avoid a mid-air collision. The fact that we are circling in the tight and shrinking eye of a category five hurricane makes this an extremely difficult and dangerous maneuver. These pilots are the best in the business. They pull off the fly-by, and I watch as TEAL 57 zooms past overhead. I see the faces of TEAL 57’s crew looking out the window, and I find myself forlornly wishing I were one of them.

“NOAA 42,” reports Self, “we got a good look at your top side and number four engine. There is no obvious damage, other than what appears to be a dislodged de-icing boot hanging from the number four engine? We’re going to exit the eye now through the east eyewall and see how rough it is for you over there. We’ll continue penetrating the eyewall until we find a soft spot for you.”

“Roger TEAL 57, that’d be greatly appreciated,” replies Lowell.

I say a huge silent THANK YOU to the brave crew of TEAL 57. They are risking their lives for us. The extreme turbulence in Hugo’s eyewall almost killed us, but they are willing to brave it multiple times in order to find us safe passage. They leave their comm link open as they penetrate, and we listen in as Hugo’s awesome winds give them a terrible beating.

“Better not try the east eyewall!” Self ruefully informs us, after they finish their penetration. “We’ll circle around to the south now, and come into the eye through the south eyewall.”

Gerry keeps us circling the eye, but has now pushed us as high as our three engines will take us. We are at 7,000 feet. Any further attempts to climb bring the temperature needle on the overtaxed number four engine into the dangerous red zone. We must exit Hugo’s eye at 7,000 feet.

A few minutes later, the intercom crackles to life again with the voice of Commander Self.

“NOAA 42, the south eyewall was just as bad as the east eyewall. We’re going to take our center fix now and exit through the northeast eyewall; we’ll let you know how it goes.”

“Roger, TEAL 57, thank you,” responded Lowell. “We’re going to have to leave the eye soon, though. We are getting low on fuel.”

“Ten-four, NOAA 42, we’ll try and find you a soft spot.”

I look out the window at the fearsome, roiling eyewall of Hugo, hoping it won’t be my last sight. We will have to leave the eye in just a few more minutes, regardless of whether the Air Force airplane can find a soft spot. I say a prayer for our safety and the Air Force airplane’s crew. I check the area around my station, making sure everything is securely stowed away. I wait. We have been in the eye of Hugo almost an hour.

Finally, the intercom comes to life again. “NOAA 42, this is TEAL 57. We have just penetrated the northeast eyewall, and it wasn’t too bad! You might want to give it a try. If you look on your radar display, you should be able to see where a weakness has developed in the northeast eyewall.”

I look over at my radar display. Sure enough, an area of weaker echoes has developed in a narrow section of the northeast eyewall. If we can hit the soft spot just right, the ride might not be too rough. I wonder how long it will take us to maneuver to get lined up for a shot at it.

Not long, it turns out. Gerry’s voice, terse and determined, comes in over the intercom: “Okay, we’re going to follow the Air Force airplane out now. Make sure all gear is stowed away. Set Condition One!”

Out of the Eye
We hit the eyewall. Darkness falls. Intense blasts of turbulent wind rock the airplane. Torrential rain hammers the fuselage. The winds shoot up to 170 mph, gusting to 190. The three remaining engines whine and roar as Gerry fights off a powerful updraft. The turbulence is rough, but survivable. We cross the inner eyewall without hitting any incredible jolts like those that nearly knocked us from the sky on our way in.

Half a minute gone, one minute to go. The turbulence lessens. The updrafts and downdrafts diminish, the winds drop to 150 mph. We are definitely in a weak region of the eyewall! The radar display shows yellows and greens surrounding us, where before there were only the strongest reds and oranges.

One minute gone, half a minute to go. The airplane is barely shaking now, the turbulence is so light. It is hard to believe we are in the eyewall of Hugo! We are not ready to celebrate yet, though. Hugo is not to be trusted. The big plane lumbers on towards the edge of the eyewall.

Finally, SUNSHINE! YES! We made it! The sullen dark clouds of the eyewall slip away and the sun shines down at us through a thin veil of high cirrus clouds. A huge smile of jubilation replaces my worried frown.

Praise God! The sun never looked so good. We are alive! We survived the eyewall of Hugo a second time! I can hear cheers ringing out from the crew in the cabin behind me.

“Nice flying, Gerry!” I call out over the intercom.

“That wasn't too bad,” Gerry replies, matter-of-factly.

Epilogue
Hurricane Hugo smashed through the Caribbean and Southeastern U.S. with incredible fury over the next week, killing hundreds and causing over $9 billion in damage — the most destructive hurricane in history, at the time. NOAA 42 spent a month on Barbados undergoing a thorough check of its structural integrity before it was cleared to fly back to Florida, where it received a three-month long maintenance overhaul. No hurricane-related damage to the aircraft was found, except for the missing de-icing boot on the #4 engine and a failed fuel control sensor on the #3 engine. Analysis of the data taken during our amazing flight into Hugo revealed that we hit a tornado-like vortex embedded in the eyewall when the hurricane was at its peak intensity.

When the next hurricane threatens our coast, the Hurricane Hunters will be in the storm. Say a prayer for them.