Regional Turboprop ATR 42-300 with 46 Aboard Crashes Over Andes

If you've flown on a regional airline using ATR, Embraer, de Havilland, Dornier, SAAB or Fokker airplanes or others, you have some idea of the plane which crashed yesterday evening after takeoff from Alberto Carnevalli Airport in Merida (MRD/SVMD) enroute to Simon Bolivar airport in Caracas, Venezuela. The ATR 42-300 is so named because it carries about 42 passengers depending on configuration, and that full count of passengers as well as crew (a total of 46) were lost as the aircraft, according to the BBC, flew into a rock wall in the mountains surrounding the airport.

AviationSafety.net notes that this is the 18^th loss of this type of aircraft, and the 8^th worst aviation accident in Venezuela. EADS, the European aerospace giant, owns a large portion of ATR and also the European large aircraft manufacturer Airbus. The Merida airport is, says the BBC, notoriously difficult for pilots because it is surrounded by high mountains. Because of this, pilots are given special training. Weather conditions were said to be normal, though mountain flying can involve very complex weather and wind conditions, sometimes rapidly changing, and taking off from a high altitude adds other challenges. No indications of trouble were noted, no distress calls were given, and the accident occurred about six miles from the airport shortly after takeoff.

One note that Wikipedia makes about the ATR 42-300 is that it doesn't contain a separate unit for providing standby power on the ground (APU), but uses one engine with the propeller disengaged. Because of this, part of the maintenance procedures involves switching the engines periodically to balance the operational time on each. Wikipedia also notes that the airplane has an unusual rear entry for passengers instead of the usual front entry common today. The BBC notes that the plane was said to be 20 years old with no history of problems and well maintained, and the pilot had 8 years experience.

The ATR website notes that their regional airplane is designed for demanding and unusual airport configurations such as the one at which the incident occurred. The planes are employed in regional passenger and cargo airlines around the world, including other high altitude, high temperature and other special condition airports.

High altitude and hot weather place increased demands on a plane during takeoff, and as a pilot I have experienced the difference during summer flying, the current conditions in South America. In the busy Boston area, being instructed by air traffic control to climb quickly to avoid proximity to another aircraft can be a very stressful experience in a small, low-power Cessna further limited by conditions. Also, a favorite central Massachusetts airport surrounded by tall trees has claimed the aircraft of a number of private pilots, including an acquaintance of mine. While my current home of Denver is less crowded in the skies, the high altitude and hot summers add additional difficulties, and flight schools offer specific training before pilots venture into the nearby Rocky Mountains.

Adding the challenge of quickly gaining altitude to clear mountains creates a situation which demands top performance from the airplane and top skills from the pilot, and leaves much less room for error and time for recovery from problems. Many of the usual recovery procedures from insufficient power or aircraft lift may have been unavailable to the pilots, and especially so with a full passenger load.

The aircraft was, according to the BBC, reported nearly "pulverized" by the impact, and access to the crash site was difficult. Investigation details were not yet available. Those waiting for the flight's arrival in Caracas were being offered counseling.

"Aircraft Accident Description ATR 42-300 YV1449", http://aviation-safety.net/database/record.php?id=20080221-0

"ATR 42", http://en.wikipedia.org/wiki/ATR_42

"'No Survivors' in Venezuela Crash", http://news.bbc.co.uk/2/hi/americas/7258117.stm

"ATR 42-500", http://www.atraircraft.com/public/atr/html/products/products.php?aid=508