PERSPECTIVE FROM A NOAA HURRICANE HUNTER
By Cmdr. Ron Philippsborn, NOAA Corps
NOAA P-3 "Hurricane Hunter" Pilot
One of our mechanics once described flying into a hurricane, from his perspective back in the cabin, as something like riding in a big semi going 90 miles an hour down a windy, bumpy dirt road in the desert at night, with the headlights turned off. Of course, our view from the cockpit is a little different.
NOAA's Lockheed WP-3D Orions take off in clear weather, hundreds of miles from the storm, lumbering slowly into the warm, moist tropical air under the weight of 10 hours worth of jet fuel, plus reserves (fuel makes up almost half of the P-3's total weight on a "max mission"). The transit out to the storm, typically at 17-18,000 feet is uneventful, as the scientists and technicians check out sensors, radars and data acquisition systems. Approaching the storm, we inform Air Traffic Control that we're "going operational" and descend to the researchers' desired altitude, normally anywhere from 1,500 to 14,000 feet, depending on the experiments to be conducted. Often, the two P-3's will enter the storm from different sides, crossing in the eye on perpendicular headings.
We get closer to the hurricane, and the crew secures the cabin, putting away or strapping down all loose objects. As we begin to penetrate the outer rain bands, the Flight Director, the individual responsible for coordinating the mission, uses the big C-band belly radar to set a track for the eye, and the plane takes the first few bumps, flying into and out of the rain. Within 100 miles, the eyewall starts to show up on the pilots' nose radar; the winds are now steady at 40-60 knots off the left wing. The open spaces between the clouds become fewer and fewer until we're completely enveloped, relying completely on our 1960's-vintage instruments. The winds slowly increase, and the turbulence becomes more pronounced, as the stiff-winged P-3 is jostled around the sky. Sixty miles out, the eyewall now shows up clearly on the nose radar as a hard, sharp, bright red arc across our path. Because of the crosswind, the pilots have the plane in a 10-15 degree crab to the left to stay on track, and are starting to fly "uphill" (The pressure is dropping as we approach the center of the hurricane, and the pressure altitude falls with it, so the plane has to "climb" to maintain a constant altitude above the waves).
We near the eyewall, a solid circle with the inner rainbands converging into it. Everyone is strapped in; the turbulence more and more pronounced, rain pelting the windshield. The airspeed starts to fluctuate as the P-3 experiences sharp up- and down-drafts. The pilots fight to maintain straight and level, the Flight Engineer jockeys the power levers to maintain the airspeed within limits. We hit the eyewall. The winds climb rapidly, 90, 110, 125 knots, howling at the airplane from the left side, and the plane starts to buck. The crab angle is now up to 22-27 degrees and the power levers are jammed full forward as the propellors claw for altitude. Wind shears hammer the P-3 up and down; the rain is like a fire hose blasting the windows. The plane shakes so violently that the numbers on the instrument panel are unreadable. Yet, amidst the chaos, the voices on the intercom are calm and composed, people going about the business of science. One last updraft on the inner edge of the eyewall slams into the belly of the plane. . . and suddenly all is calm. We're through the eyewall and into the eye, and the view is breathtaking. The surrounding wall of clouds, beautiful, menacing and awe-inspiring all at the same time, looms tens of thousands of feet into the sky, encircling us, gently curving outward in a "stadium effect." Above us, clear blue sky; below, an angry sea whipped into a frenzy by howling winds. Occasionally, we see birds trapped in the eye.
There is little time to enjoy
the scenery. The Flight Director calls out a rapid succession
of course changes as we hunt for the center of the wind circulation
amid the swirling eddies. We mark the center, drop an expendable
weather instrument and turn outbound, and there ahead of uswaiting,
blocking our pathlies the raging eyewall once again. The
"Fasten Seatbelt" goes on . . .