| Home | Articles | CP reprints |SUCKER HOLE
Thursday, July 30, 1992
My flight is from Tallahassee to Oshkosh with a lunch stop at Huntingburg, Indiana. The Tallahassee Flight Service weather briefer warns of two frontal areas, one over Chattanooga, TN and one extending from Champaign, IL to Ohio across my route. "VFR not recommended" is read like a Miranda notice. Haze and two miles visibility at TLH means a special VFR departure; no problem. I climb quickly to 6500 feet and head north. Cloud cover below soon becomes solid. At Chattanooga, I am VFR on top. Flight watch informs of the frontal activity from Champaign, IL to Ohio with many thunder storms across my route. "VFR not recommended" results in a "Roger" acknowledgment. The Flight Watch briefer adds, "You are not going ahead, are you?". Another "Roger your information, thanks" ends the discussion. Soon the solid cover breaks and I land at Huntingburg after four hours, thirty minutes flying from Tallahassee.
A micro waved sandwich, some fuel, and I climb to 8500 feet, anticipating the need soon to reach 10500 feet to pass over the Chicago TCA. From west to east, as far as I can see ahead are towering cumulonimbus formations, perhaps ten miles apart. As I approach Terre Haute, IN, I see no breaks in the line. Where a CB ends, solid clouds with light to moderate rain fill the gaps. Turning westward, I head sixty or seventy miles toward Champaign, which is reported to be the end of the easterly moving frontal activity. However, I see blue sky through a gap in the line of CBs at my altitude and I turn into my personal "sucker hole".
Light turbulence and light rain cause me to glance down to pull on carburetor heat, reduce throttle setting, stabilize the aircraft, and slow the Long-EZ to the maneuvering speed of less that 120 knots. The I glance at the altimeter. Instead of 8500 feet, it indicates 13400 feet. Up a mile in seconds! Suddenly, I see lightning off my left wing. The VSI is pegged at 2000 feet per minute, worthless! Now I move the throttle to idle and the nose down ten degrees for an airspeed of 110 knots. The light rain becomes heavy rain, then hail. The turbulence is minor; the altimeter slows at 15600 feet. An ascent of a mile and a half in seconds means the updraft is over 100 miles per hour! There is no sensation of the vertical speed. The plane seems to be flying at 110 miles per hour straight and level. Yet, what goes up . . .
As the plane passes from the 100-plus mile per hour updraft into the compensating down draft, the sharp shear force is tremendous. The plane shudders, as if it has hit a solid wall. Negative G-forces cause everything in my shirt pocket to fly out; the ELT pops out of the clamps holding it in place. In spite of a tight seat belt, my head hits the canopy. During a flight from Bogotá to Panama on AVIANCE Air Line, I experienced CAT. Passengers and hand luggage flew through the cabin but this hammering shock of the sharp wind shear is far, far worse. The shuddering of the aircraft is the heaviest shock I have ever felt in a plane, so bad I do not expect to see the wings still attached. My first thought is "If this is it, so be it". This is interesting, as I never use this expression. My second thought is "Thanks, Burt Rutan for designing a strong aircraft, and thanks Tom Caywood for building to specifications". The rest is anti-climatic as the down draft takes back the free ride up and I enter clear air at 9000 feet.
Using Rich Domke's hand held VOR, I find Mattoon, IL and stop for the night. After climbing out of the Long-EZ, I was shocked when I saw the hail damage to the leading edges of the canard and wings and the amount of paint removed from the landing struts and winglets. Immediately, I walked to the rear to inspect the prop. By the time I entered the hail, I had pulled the throttle back to idle. With little or no thrust or drag, there was no wood damage. The urethane leading edge of the wood prop eroded slightly along the outer ten inches. Close visual inspection of the EZ revealed no signs of cracks or stressed structural areas from the outside.
Early Friday, July 31, 1 flew out of Mattoon to Oshkosh. The damaged canard destroyed almost all the laminar flow, requiring full aft trim and some positive stick pressure to maintain straight and level flight. At Oshkosh, I talked to Burt Rutan about the hail damage.Burt, Mike, Bruce Tifft and I were all parked together. Mike held an informal discussion and information exchange session for Rutan builders and flyers at the Defiant every day at 1:30PM. After the Saturday meeting, he examined the aircraft and reassured me concerning structural damage. Then, he advised me to flox the holes where the hail cut through to the foam and apply micro to reform the leading edges of the canard and wings.
Bruce Tifft showed everyone how great his prop resisted the forces that destroyed the leading edges of the wings and canard. He also advised me to sand lightly with a fine grit paper to restore the polish to the urethane leading edge.
The hole revealing the blue sky had ample room for the plane to fly through. The surrounding rain and clouds were very light in color, not the dark mass normally associated with cumulonimbus and severe thunderstorms. No lightning was visible from outside the clouds. The thunderstorm was imbedded. Yes, I was suckered.
Once the hole closed, I should have made an immediate 180 degree turn to exit. Then I could have continued VFR westward to pass the end of the line or find an airport and land until the weather improved.
Never let the urgency or desire to arrive at the destination interfere with flying judgment and decisions. Respect the the power of nature. Do not let the attraction of a light, thin area of clouds and light rain prevent thinking rationally. There may be a "sucker hole".
Due to the tremendous sharp wind shear between the strong updraft and down draft, I do not believe an aluminum light aircraft could have withstood the abrupt shock of the shear force encountered. The impact was incredibly severe.
9850 SW 15 Street
Miami, FL 33174