Disaster Averted!

Photo from CRW Facebook

A few days ago, a US Airways Express CRJ 200, operated by PSA, narrowly escaped disaster when the crew decided to abort a takeoff from West Virginia's Yeager Airport (KCRW) in Charleston.. You can see by the skidmarks that heroic efforts were made to stop the aircraft. Thirty passengers and 3 crew were aboard. All survived.

This may seem like a routine incident that may have flattened a few expensive tires and bruised some egos, but what is not apparent in the photo is that the nose of the aircraft is a mere 100 feet from a precipitous 1000 foot drop down to the suburbs below. You see, Yeager Airport is built on a high plateau and two of its runways end abruptly on ledges of granite.

KCRW is a challenge anyway. Because of the aircraft carrier-like runway ends, the surrounding mountains, high field altitude, short runways and frequent bad weather, it is one of the most demanding airports for airline flight crews in the USA. I have dispatched many flights into and out of there and I always checked conditions two or three time before I released a flight in or out of this airport. Especially in the winter. I am not saying it is a bad or unsafe airport, but extra care has to be taken by all involved because of the design.

Aerial view of KCRW from CRW Facebook

In the photo, runway 23 runs from left to right. The PSA jet attempted takeoff from runway 23 travelling from the left and ended up a hundred or so feet from the cliff at the end of the runway at the right of the photo.

Click the photo to see the expanded view.

So what happened? I am not an accident investigator but there are two factors involved here. One bad and one good.

The bad factor is that a perfectly good aircraft was unable to stop before it reached the end of the runway. When each flight is planned, many factors are considered such as temperature, payload, runway length, thrust, barometric pressure and runway contamination among others. These parameters are entered into flight planning software which produces a flight release with information the crew can use to determine what they can expect the aircraft to do under the particular circumstances from takeoff to cruise to landing. The flight releases I produce are all customized to that particular flight and no two are exactly alike. It is a precise science.

One number that is produced is called V1. Simplified,V1 is the speed (KIAS) that if below it and an engine is lost on the takeoff roll, the takeoff is aborted and aircraft must be kept on the runway and a safe stop on the runway surface is assured by the performance numbers. If the critical engine is lost on the takeoff roll above V1 speed, it is mandated that the takeoff be continued and a go-around be initiated as it is assumed that is the safer action than aborting the takeoff and attempting to stop on the remaining runway.

In other words, below V1 speed, stay on the ground and hit the brakes. Above V1 speed you are assumed to have too much energy to stop on the pavement and it is safer to leave the ground and return for an emergency landing. V1 is a go/no go hard rule.

If birds were involved as in the Sully Hudson River incident and there is a dual flameout, then all bets are off if there is no engine power left to continue takeoff.

So what happened at KCRW? That's for the NTSB to figure out. All I know is that the aircraft should have stopped short of the end of the runway or continued aloft depending on the speed at the time a problem was detected by the crew and the decision was made to abort the takeoff. Its all in the numbers. Something different happened in this case.

The good factor and hero in this story is the Engineered Materials Arresting System (EMAS) that was installed at the end of RWY 23 a few years ago. EMAS is like one of those gravel filled runaway truck lanes one sees on steep downhill grades. The transition from hard asphalt to sloppy gravel slows the big rigs down fast.

EMAS works the same way. It has a substance like gravel below a thin layer of concrete. When an aircraft rolls over it the fragile concrete crumbles much like pie crust and allows the landing gear to sink into the more frictional material below slowing the plane at a huge rate. Both aircraft and passengers end up none worse for the wear. The system worked as advertised.

Which is exactly what happened at KCRW. If not for the foresight of someone in the Aviation Authority of Charleston, WV to invest in this technology (and it is not inexpensive) there would be 33 fatalities at the bottom oft that cliff right now. Way to go!

Note the EMAS symbol at the end of RWY 23 middle left.

Below is an airport that is in bad need of an EMAS overrun. This is KSGU in St. George, Utah. It is built on top of a volcanic mesa with steep drop offs at each end of the runway. I used to live there and flew in and out of that airport many times. Each departure and arrival was an adventure! A new replacement airport is currently being built on flatter ground northeast of the city.