Although falling airplanes and injured spectators may seem the most obvious risks at air shows, organizers also must worry about other problems.

For example, "What happens if it rains and I'm hooked with $75,000 in performer fees and five tons of potato chips?" said John Cudahy, president of the International Council of Air Shows in Gaithersburg, Md.

Indeed, a two-day air show at the Royal Air Force base in Waddington in the United Kingdom nearly was canceled recently because of a deluge during the wettest June on record.

The RAF Waddington show was insured for cancellation due to adverse weather, terrorist threats, a member of the royal family dying, or an airplane crashing during rehearsals before the show opened, said Paul Byram, air show coordinator at the base.

The show went ahead despite the weather conditions but attracted only half the normal 120,000-person crowd, said Mr. Byram.

While air shows are big business for organizers, for aviation insurers they are small potatoes.

The air show market is not even "statistically significant," according to one

underwriting executive Often, governments or manufacturers cover liability losses.

There are 450 air shows annually in the United States, according to Mr. Cudahy of ICAS, a 1,500-member trade association representing air show performers and air show organizers in the United States and Canada. About 600 air displays take place annually in the United Kingdom, according to the Civil Aviation Authority in London.

The U.S. air shows attract up to 28 million spectators per year, compared with only 15 million who attend U.S. professional football games.

About two-thirds of the U.S. shows are held at civilian airports, and the rest take place at military bases.

The largest show in the United States is held in Oshkosh, Wis., where experimental aircraft are displayed. Oshkosh attracts 5.5 million people from all over the world. Another major event is Chicago's air and water show, which attracts 2.5 million people. But some shows can be in front of crowds of fewer than 30,000, said Mr. Cudahy.

All sorts of performances will take place at air shows, from precision military flying squadrons-such as the U.S. Navy Blue Angels and the U.S. Air Force Thunderbirds-to parachutists and balloonists. Also, attractions between the in-flight feats are a growing trend, said Mr. Cudahy. For example, he said, a tractor trailer equipped with a jet engine might race an airplane down a runway.

Some of the major air shows outside the United States take place in Farnborough, England; Paris; Hannover, Germany; the Far East; and Abu Dhabi, underwriters say. Russian-built aircraft and pilots especially draw major crowds.

Safety is a prime consideration during the shows, particularly to protect the crowd. Air show producers worldwide do not want a repeat of the tragedy at the U.S. Air Force base in Ramstein, Germany in August 1988. During maneuvers, one Italian military jet collided with two other Italian jets and hurtled into a crowd of spectators. At least 70 people died, and hundreds were injured in what is considered the worst-ever air show accident.

There hasn't been a crowd fatality in the United States in 50 years, said Mr. Cudahy. That's because "the U.S. more than anywhere in the world has highly regulated airspace" to protect spectators.

In the United States, the Federal Aviation Administration's rules require that each air show have airspace boundaries in which there are no people. All other regulations govern how the display teams perform within those boundaries, said Mr. Cudahy.

For example, how close an aircraft can fly to the ground depends on the type of aircraft and the maneuver.

Pilots typically try to fly parallel to the crowd at air shows. But there also are specific regulations governing procedures for turn around and flying in the opposite direction after a display, too. They can't perform another maneuver while turning around, for example.

Each pilot also has a "low level waiver" that indicates how low the pilot can fly depending on his or her experience and the maneuver he or she is performing.

For the past six or seven years, ICAS also has administered a pilot safety program for the FAA known as the Aerobatic Competency Evaluation, said Mr. Cudahy. In this program, an experienced pilot evaluates another pilot to confirm that the pilot knows what he or she is doing. Since the program has begun, the number of pilot fatalities at air shows has dropped by two-thirds, according to Mr. Cudahy.

Outside the United States, safety regulations at military air shows and displays are governed by the Standard NATO Agreement, which lays down safety rules for aircraft and pilots, said Mr. Byram of RAF Waddington. They govern, for example, the separation needed between aircraft displays and the crowd.

Most safety regulations for air shows throughout Europe run along the lines of the NATO agreement, said Mr. Byram.

However, safety regulations in the United Kingdom for air shows on civilian property are governed by the individual organizers and the CAA.

"We have a book full of rules," said a CAA spokesman in London. The book is known as "Flying Displays: A Guide to Safety and Arrangements."

Some of these rules include making sure the aircraft is properly certified; pilots have adequate training and experience; and displays won't endanger the crowd, said the spokesman. "The primary concern is the safety at the air show, (for the) crowd and the participants."

No spectator has died at a U.K. air show since the 1950s, said the CAA spokesman.

Insurance coverage for air shows varies depending on the size of the show, the organizer and the performances.

"Air shows are not statistically significant" to track separately like airlines or aircraft manufacturers, said Tony Medniuk, managing director of the British Aviation Insurance Group Ltd. in London.

If a military aircraft crashes, governments often indemnify the shows. Depending upon the cause of the crash of civilian planes, aircraft manufacturers might also incur losses under their product liability policies.

In the United Kingdom, the Ministry of Defense has a blanket third-party liability insurance policy of 40 million pounds ($67.2 million) for military aircraft wherever they display, said Mr. Byram. Aon Group Ltd. places the coverage with various insurers.

The premium for the coverage is recouped over the year by charging air show organizers for the military displays, said Mr. Byram.

Eastern European aircraft that flew at the RAF Waddington air show in June were added onto the Ministry of Defense policy for an additional premium, he said. Civilian aircraft at the show had to have a minimum of 7.5 million pounds ($12.6 million) in third-party liability insurance.

Aon also offers specific coverage for Eastern-built aircraft that fly at any air show, said Mikal Sanne, account handler at Aon in London. The coverage is led by Westminster Aviation Insurance Group.

Though air show organizers usually require display teams to buy liability insurance, there is no legal requirement for civilian aircraft to buy it, said the CAA spokesman.

The RAF Waddington air show also bought 25 million pounds ($42 million) of general third-party liability insurance for ground risks through broker Sterling Cooke International in London, said Mr. Byram.

In Europe, officials of each show decide what coverages display teams and exhibitors must buy, "and everyone goes out and buys them," said Mr. Sanne.

The third-party liability limits required vary from $75 million to "the highest I've seen, which was 200 million deutsche marks ($109.6 million) in Berlin last year," said Mr. Sanne.

One of the largest air shows in Europe is held every other year in Paris and known as the Salon International de l'Aeronautique et de l'Espace. The show was held in June and attracted about 286,000 visitors and 1,850 exhibitors, said a spokesman. There were no aviation accidents.

To exhibit at the Paris show, each aircraft exhibitor had to buy a minimum 100 million French francs ($16.3 million) third-party liability insurance policy to cover "damage which might be caused by the aircraft to all third parties and particularly to other exhibitors," the contracts stated.

The Paris air show organizer also agreed to buy a liability insurance policy to cover "damage which may be caused to visitors or third parties" during flight demonstrations, the contracts stated. A spokesman did not know the limit of the coverage.

The organizers also agreed to buy property insurance for the exhibitors for all risks except theft. The property policy covered damage "from fire, explosion, lightning, and falling aircraft" as well as flooding.

The other major air show in Europe is held in Farnborough in the United Kingdom in years the Paris show isn't held. It usually attracts 130,000 industry visitors and about 150,000 members of the public, said a spokesman for the organizers, the Society of British Aerospace Companies.

Farnborough requires exhibitors bringing aircraft to the show to buy at least 50 million pounds ($84 million) in third-party liability insurance, "and we get a certificate to that effect," said the spokesman. SBAC will help arrange this coverage through its broker, Willis Corroon Group P.L.C., he said.

Many other risk management-related issues that air show organizers must deal with are outlined and discussed by the World Federation of Air Show Congress on a World Wide Web site.

The site, for example, offers a show plan checklist that includes whether the organizers have:

An independent safety observer; security; emergency contingency and communications plans; emergency medical and fire rescue teams.

Insurance policies, including for air show liability, accident, property theft, liquor liability, workers compensation and fireworks.

For more information, contact the World Federation of Air Show Congress via its Web Page: http://members.aol.com/kcaishow/index.html