A little after noon last Sunday, a Learjet 60 from Texas carrying a family, their nanny, two friends and two pilots was flying across Florida at 35,000 feet on their way to the Bahamas. The co-pilot, Nathalia Filgueiras, radioed Miami Air Traffic Control Center that they had light, clear ice that was manageable with moderate turbulence and asked for permission to climb to 37,000 feet, presumably to get above the storm.
About ninety seconds later, she was calling mayday and the pilot was reciting the Lord’s Prayer. The airplane went from 35,000 feet to a crater on the ground in roughly 76 seconds, and on Tuesday NTSB investigators announced they’d found most of the jet’s left elevator — part of the tail assembly that steers the plane — scattered in three pieces across 3.8 miles away from the hole in the ground. The tail had come apart in the air.
While I’m not rated to fly jets, I’ve been a licensed pilot since I was 21 years old and one of the first things any flight instructor pounds into your head is that thunderstorms kill airplanes. The most dangerous ones aren’t the fully-formed ones you see on radar from 100 miles away, but the ones that are rapidly building.
That’s because a growing thunderhead is an engine converting moisture into vertical motion, and the faster it’s boiling up the more violent the air inside it is.
So far, with just that information, this might look like pilot error, until you look at what happened with this particular cell. It grew from 33,000 to 48,300 feet in about 20 minutes, which is so explosive — growing 3 miles taller in that short time — that it’s mind-boggling. I’ve never even heard of such a thing, although it’s unlikely this is entirely unique these days.
The FAA’s thunderstorm guidance tells pilots to not just avoid any storm that tops above 35,000 feet but to stay at least 20 miles away from them. The pilot had flown around a larger, more mature storm and then punched right into the middle of this cell, probably with no idea how violent it was becoming.
So the real question that the media should be pursuing is why this thunderstorm grew so high, so fast, and why the pilot wasn’t warned about it by Air Traffic Control and the National Weather Service. When it started dropping rain that weekend, Palm Beach Gardens got 17 inches of rain in six hours, nearly double the threshold for a once-in-a-thousand-years event. Parts of Melbourne were hit with more than 26 inches of rain in that one day.