Powered Parachuting Double Fatality

On August 24, 2012, about 1800 eastern daylight time, an experimental Destiny XLT powered-parachute, N1674A, impacted terrain following a downwind turn at the Silver Lake State Park near Hart, Michigan. The 66 year old airline transport pilot and the passenger sustained fatal injuries. The powered-parachute's frame structure sustained substantial damage. The aircraft was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Day visual flight rules (VFR) conditions prevailed for the flight, which did not operate on a VFR flight plan. The flight's origination and destination are unknown.

The pilot held an FAA Airline Transport Pilot certificate with an airplane multi-engine land rating. He also held commercial pilot privileges in gliders and single engine land and sea airplanes. He further held a flight instructor rating in gliders and in single and multi-engine airplanes. The pilot held a second-class medical certificate dated December 30, 2010. On the application for that medical certificate, he reported his flight experience included 24,500 hours of total flight time and 200 hours in the six months prior to the certificate exam.

Witnesses driving Jeeps on sand dunes located near the accident site recorded amateur video of their Jeep activities while on the dunes and happened to capture the accident on video. The video shows that the powered parachute was flying above the dunes area. The powered parachute turned and flew in an area where wind flags indicated a gusty downwind condition existed. The powered parachute cart is then observed to porpoise and rock fore and aft. Simultaneously, the parachute also flies fore and aft above the cart, until the left side of the parachute deforms and collapses. The powered parachute then enter a descending left spiral. During the descent, the left side of the parachute reinflates., and the powered parachute impacts terrain nose down with an inflated canopy.

The powered parachute ram-air canopy retains its airfoil shape because of the relative wind airflow entering its front openings. Examination of the accident powered parachute revealed that modifications to lower the canopy's angle of attack had been made. The modifications allowed for quicker rotation and additional forward speed, but they also decreased the canopy's angle of attack such that it would partially collapse when wind gusts were encountered. Like in this video.

At 1754, the recorded weather at the Fremont Municipal Airport, near Fremont, Michigan, was: Wind 150 degrees at 5 knots; visibility 7 statute miles; sky condition clear; temperature 30 degrees C; dew point 13 degrees C; altimeter 30.02 inches of mercury.

The National Transportation Safety Board determined the probable causes of this accident to be the partial deflation of the powered parachute canopy when the pilot flew the aircraft into an area with gusty wind conditions. Contributing to the accident were the modifications that changed the flying characteristics of the parachute.

~~~

A powered parachute flight instructor obtained a copy of the accident video from a source outside the investigative parties. He reviewed the video and wrote the NTSB investigator in charge an e-mail in reference to the accident flight. His communication, in part, stated:

"It is clear from the pictures that there were two additional links (per side) added to the rear risers, this would raise the rear of the chute by approximately 3 inches over its intended connection point. In addition to the extra links the front lines of the chute have apparently been knotted (perhaps in an attempt to shorten them, as these lines tend to stretch faster than the other lines, although I have never seen this done before).

As I mentioned before, this practice of adding links became popular with some due to the stretching of the forward lines and increased difficulty of inflating the chute (the chute would not fully rotate for takeoff) it lowered the angle of attack creating a quicker rotation and additional forward speed. Watching the video of the accident seconds before the collapse you can clearly see the chute heave backwards as the first gust hits the chute, you can then see the chute lunge forward, about that time, you can see the effects of a second gust hitting the chute and pushes it back even further creating a pendulum effect. When the chute tries to correct itself, it will overfly the cart as it pendulums.

It is my belief that due to the additional links being added and lines being knotted that it decreased the angle of attack to the point it collapsed when confronted with the gusts and subsequent downward pitch of the wing."

Visit our sister project @Real World Police

Видео Powered Parachuting Double Fatality канала What You Haven't Seen