The cause of John F. Kennedy Jr.'s apparent fatal plane crash may not be known for some time, if ever, but it is clear he was flying into conditions that have lured many other pilots to their deaths.
Kennedy was a relatively novice pilot flying a high-performance aircraft over the ocean on a nearly moonless night as a summer haze hung over the Northeast, a dangerous combination of factors.
That meant that he was likely flying into what pilots call a "black hole" while searching through the haze for the first pinpoints of light on Martha's Vineyard. Human beings tend to become disoriented when they are suspended in blackness and have almost no "visual cues." It is easy to believe that up is down. That is why planes have instruments, and pilots are told to believe their instruments rather than go with their senses.
Nonetheless, the flight into Martha's Vineyard should not have been beyond Kennedy's capabilities as long as he followed that basic rule of "trust your instruments."
However, Kyle Bailey, another pilot who was considering a trip to Martha's Vineyard Friday night, said he decided against the trip because of the haze.
"The weather was very marginal, four to five miles visibility, extremely hazy," Bailey said. "Over open water, you have reduced visibility anyway. With the haze, in the dark, you lose sight of the horizon. You don't have landmarks."
Common illusions also sometimes fool even airline pilots in dark and extreme situations. The Civil Aeronautical Medical Institute at Oklahoma City has done extensive research on the illusions, which can make the mind believe that an aircraft is turning, climbing or performing some other maneuver when it is actually in level flight.
Kennedy's Piper Saratoga PA32 II HP took off near sunset from the airport at Caldwell, N.J., on a flight that first would take him low under the busy airspace of New York's major airports, then up to a somewhat higher altitude over Long Island and then out over the Atlantic.
Kennedy was flying under what is called "visual flight rules," meaning that he filed no flight plan and navigated on his own, guided by radio beacons or possibly by Global Positioning Satellite.
Bailey said he had seen Kennedy take the flight many times, and he usually took a flight instructor with him when the weather was "iffy." There apparently was no flight instructor aboard Friday night.
However, the weather did not appear to be "iffy." Despite the haze, the National Weather Service's aviation weather observation at the apparent time of the crash was listed as eight miles visibility and clear. Conditions also did not appear conducive to fog. The weather observation offered no special remarks suggesting dangerous weather.
The National Transportation Safety Board sent investigators to the scene last night. Authorities said the visual aerial search was suspended at dark, but an infrared-equipped Air National Guard helicopter was continuing the search.
Like others, David Learmont, longtime safety editor of Flight International, has called for a review of night flying. He has called nighttime visual flying "a trap which catches many aviators and ought to be reviewed. Good visibility exists only when there is strong moon or starlight, and even then the visual clues differ in daylight."
The Aircraft Owners and Pilots Association's annual report on safety notes that one of the major causes of crashes is poor pilot judgment in continuing to fly visually into conditions that call for full reliance on instruments, called "instrument flight rules." Most often, the reason for the need to switch to instruments is weather, and darkness adds a major complication.
Continuing to fly visually into deteriorating conditions "does more damage than thunderstorms, icing and most other weather hazards combined," the association said.
To be sure, there are many possible causes of general aviation crashes, related to pilot error and faulty equipment. The NTSB and the AOPA estimate that 71 percent of fatal general aviation accidents are pilot-related. However, a significant number of accidents -- 14.1 percent -- are maintenance-related, and a lesser number involve in-air collisions, drugs and alcohol, fuel mismanagement and pilot incapacitation.
General aviation pilots have a worse safety record than commercial pilots, but general aviation safety has steadily improved over the years. In 1998, the safest year ever for general aviation, the rate of fatal accidents was 1.35 per 100,000 flight hours compared with 1.99 in 1982. Overall, the accident rate was 7.12 per 100,000 hours compared with 10.9 in 1982.
The greatest safety problem in general aviation is with what is labled "personal" flights such as Kennedy's, as opposed to business or instructional flights. Although 41.8 percent of general aviation flight hours are listed as personal, they account for 63.9 percent of all accidents and 66.8 percent of all fatal accidents.
Determining a cause will be extremely difficult in the Kennedy case, with few clues apparent last night. Safety board investigators are adept at reading aircraft wreckage much like a book, but they must first find the key piece of wreckage that might yield a clue.
Kennedy was a relatively recent pilot, and in a USA Today interview last year he suggested that some of his family members were reluctant to travel with him. He received his student pilot license from the Federal Aviation Administration in 1997, and on April 22, 1998, he got a license marked "aircraft single engine-land," meaning he could fly only single engine aircraft and could not fly float planes that land on water. The FAA said its records do not indicate that he had an instrument rating, which allows pilots to fly when they can't see anything out the window.
Kennedy's exact number of hours in the air, the usual gauge of experience, could not be learned for certain. But Kennedy was clearly what aviators call a "low-time" pilot. Sources said he had flown a little more than 100 hours, an experience level that has proved to be one of the most dangerous periods for new pilots because they have enough knowledge to fly but lack the experience of more seasoned pilots.
Getting a pilot's license is not like getting a driver's license. The requirements are much stiffer, and a novice pilot's first hours flying are watched over by a FAA-certified flight instructor.
Chuck Suma, president of New Piper, the plane's manufacturer, said Kennedy bought the plane in April and had toured the New Piper plant in Vero Beach, Fla., while in town for flight training.
The aircraft has a reputation as relatively easy to handle and has a good safety record, although it would present an added workload to the pilot because it has such features as retractable landing gear. It is more complex in many ways because of its high-performance characteristics, which include a more powerful engine and capacity to fly at faster speeds.
Kennedy's red-and-white aircraft was built in June 1995. The six-seat, low-wing plane had a six-cylinder, 300-horsepower engine with a range of more than 900 miles and a cruising speed of more than 180 miles per hour. New, the plane costs $325,000 to $350,000. FAA records show that its most persistent problem with such planes was the welds in the exhaust that caused cracking and sometimes caused fires and engine failures. The exhaust system accounted for 46 FAA service difficulty reports.
However, Drew Steketee, senior vice president at the airline owners association, said the problem was fixed years ago. Records show the last complaint was in August 1998, and almost all the others were from the early-to-mid-1990s.
Another early problem was "tail flutter," a vibration and oscillation that can cause the tail to rip off in flight. Steketee said that problem was also fixed years ago.
On the Kennedy plane itself, there was only one service difficulty report; in 1997 before he owned the plane, the previous owner reported a bolt rubbing on an engine part. A bracket was manufactured to keep the bolt clear.
The Flight Toward Martha's Vineyard
John F. Kennedy Jr. was traveling to a wedding in Hyannis Port, Mass., on Cape Cod, with his wife, Carolyn Bessette Kennedy, and her sister, Lauren Bessette. They were to bring Lauren to Martha's Vineyard before continuing on to their final destination.
Top speed: More than 180 mph
Cruising range: 900 miles
Length: 27.9 feet
in this model:
In 13 incidents since 1989, 8 fatalities, 11 injuries
Plumbing the Depths
Saturday evening, NOAA's charting vessel RUDE began searching for debris from the Piper. It is the same ship that searched for wreckage from TWA Flight 800 off Long Island in 1996.
RUDE employs two types of sonar:
* Multibeam sonar accurately measures depths, charting a three-dimensional diagram.
* Side scan sonar searches for objects on the sea floor, creating a shaded "picture," such as the sunken barge shown at far right.
1 Friday, 8:38 p.m.
A Piper Saratoga owned by Kennedy leaves Essex County Airport near Fairfield, N.J. The weather on the intended route was quiet, with light clouds, light wind and some haze.
2 Friday, 9:39 p.m.
The last radar signal is received from the plane as it made its approach to Martha's Vineyard Airport.
3 Friday night
About an hour after the plane was due on Martha's Vineyard, a driver reported it overdue, NBC News said, but it did not specify who the driver alerted.
4 Saturday, 2:15 a.m.
Kennedy family notifies Cape Cod Coast Guard that the plane had not arrived. Coast Guard notifies the Federal Aviation Administration, which contacts airports to determine if it had landed elsewhere.
5 Saturday, 7:30 a.m.
The Air Force and Coast Guard launch a search with at least 20 aircraft and two boats between Long Island and Martha's Vineyard. Other agencies and civilians join in the search.
6 Yesterday afternoon
Luggage bearing the tags of Lauren Bessette is found in the waters off Philbin Beach, with other debris.
7 Saturday, 2 p.m.
Authorities close Philbin Beach, warning swimmers they might be in danger of being cut by debris.
SOURCES: Federal Aviation Administration, National Oceanic and Atmospheric Administration, The New Piper Aircraft Inc., Maryland Nautical Sales