1. Catastrophic engine failure at a critical moment during take-off.
2. Excessive energy (velocity) at landing leading to an overrun.
3. Severe turbulence, either expected (storms) or unexpected (clear air turbulence).
4. Fire on the ground or in-flight.
These scenarios have to be controlled at all costs, or the consequences can be ugly. Number three is the hardest to control, since we must go on our flights, no matter the weather. Yeah, we will delay a bit here and there, cancel a flight every now and then (but the next one will go), or will be snowed under in Boston, but we are going, one way or the other. Managing number three takes experience; number one, two and four can be taught, tested, and drilled over and over until it is second nature.
The problem comes with the old saying familiarity breeds contempt. Modern airliners are reliable beasts with good safety records. This leads to thinking about that good looking flight attendant in the back rather than what will I do if number one engine turns into hot shrapnel at 160 m.p.h. or where could we land right now if the rear galley catches on fire?
Last night, we got a good look at worry item #2. My co-pilot, a young and sharp kid whom I have flown with many times, was the flying pilot enroute to Connecticut. The flight eastbound was smooth and fast. Our average tailwind was over 130 m.p.h. putting us into the Hartford area forty minutes ahead of schedule. The co-pilot was doing his usual good job and I was expecting an uneventful landing.
Even so, I am always looking for little uh-ohs that might become big Uh-Ohs. I noticed we were really moving across the landscape as he was descending to intercept the radio beam that leads to the runway. I checked the inertial navigation platform digital readout; a 40 m.p.h. tail wind at 3,000 feet. Our airspeed was 200 m.p.h. and slowing but our groundspeed (also energy state) was quite a bit higher at over 240 m.p.h. The co-pilot started calling for landing gear and flaps, which I selected and checked. We were fully configured for landing at 1,000 feet with an airspeed of 160 m.p.h., but a ground speed of 200 m.p.h. Still a 40 m.p.h. tailwind pushing us toward the airport. The descent rate was way too high, because the faster the aircraft is crossing real estate, the faster it has to lose altitude in that given distance. We had a perfect scenario for a runway overrun; too much energy to lose and not enough pavement to do so. It's an insidious problem that has caused a lot of heartache... Energy increases with the square of the speed increase.
The control tower guys were reporting a crosswind of 10 m.p.h. on the surface, quite a change in only 1,000 feet vertical distance, but in no way uncommon. At 800 feet above the ground, the co-pilot turned the whizbang stuff "off" and selected emergency flight controls (stick and rudder) to make the landing. At 500 feet, the wind still at 40 m.p.h. on the tail, began to abate and rotate off the tail. Too late, though... Our groundspeed was too high. The co-pilot was watching the situation and said' "This isn't looking good skipper."
I agreed with him and suggested a go-around for another runway with favorable winds. The co-pilot raised the nose to intiate a climb, at the same time pushing the thrust levers forward to maximum go-around power. Holy Moly! We were shoved back into our seats as the engines transitioned from idle thrust to maximum go-around thrust. The fuel flows went from 800 lbs. to north of 10,000 lbs. Might as well cut a six inch hole in the bottom of each wing tank. The co-pilot called for "landing gear up, flaps to 18 degrees."
The control tower cleared us to land on a more wind friendly runway. In my best Captain's voice, I assured the folks that everything was OK and gave them the short version of why we did not land on the first attempt. A few minutes later, the co-pilot pulled the reverse thrust levers up and over to open the cascade vanes; the aircraft's nose lowered significantly as it morphed from an agile flying machine to an ungainly ground vehicle, via reverse thrust, wing spoilers, and wheel brakes.
The go-around took 12 minutes and 2,000 lbs. of fuel... A small price for a safe landing, though.
Day number two of a four day is done. Tomorrow night; Anchorage. Life is good!