ASSOCIATED PRESS / JULY 2001 NASA’s Helios
breaks apart
west of Kauai
BARKING SANDS, Kauai >> Yesterday's crash of Helios, NASA's giant experimental flying wing, will not end the space agency's program to develop a solar-powered "eternal airplane," said NASA spokesman Alan Brown.
"We plan to continue with the program and develop another Helios-type vehicle," he said.
Helios broke apart at an altitude of 8,000 feet and fell into the ocean several miles west of the Navy's Pacific Missile Range Facility yesterday, 29 minutes after taking off at 10:06 a.m. The aircraft was unmanned and flown by remote control from the ground. It was the first crash of a solar-powered airplane in six years of NASA tests on Kauai.
No one was injured.
The aircraft, valued at $15 million two years ago when it set the world's altitude record for winged aircraft while flying from Kauai, was a total loss. NASA has not put a price tag on the exotic new fuel cells that were added to Helios for this summer's planned tests.
The ultimate goal is to create what NASA has called an "eternal airplane" that can fly above the weather for weeks or months at a time, performing telecommunications and photographic functions that now are done only by more expensive satellites.
NASA and Navy crews scoured the crash site yesterday hoping to recover as much of Helios as possible.
A crash investigation team from NASA's Dryden Flight Research Center at Edwards Air Force Base, Calif., was being assembled to fly to Kauai to try to reconstruct the accident and discover its cause.
As there has been on all previous test flights, there was a chase helicopter flying with Helios at the time of the crash. In the past, the helicopter has carried at least one photographer. But if there are any photographs of the crash, they will be impounded until the accident investigation is done, Brown said.
Officials from AeroVironment, the California company that designed and built Helios, declined to comment on the crash but said they may make a statement after more facts about the cause are known.
"The aircraft belongs to NASA," said AeroVironment spokesman Martin Cowely.
NASA's news release, however, noted that AeroVironment employees comprised the ground crew piloting Helios.
Helios crashed during its second major flight test in this summer's series. During its first test on June 7, it stayed aloft for 15 hours and reached an altitude of 52,000 feet. But several leaks made it impossible to start the fuel cells, so the flight was aborted and Helios landed safely.
The new fuel cells are designed to provide 18.5 kilowatts of electricity for the aircraft at night by combining oxygen from the air and hydrogen carried aboard the aircraft in pressurized tanks. During the day, Helios' electric motors were designed to run on electricity converted from sunlight by 65,000 solar panels that covered the entire upper surface of the wing. In past tests, night flight was limited to the power from nonrechargable batteries carried aboard the aircraft.
Kauai's Pacific Missile Range Facility, where the Navy tests all of its new missiles, has been the home of all NASA solar airplane tests since 1997. NASA considered the Navy's 42,000 square miles of ocean outside commercial shipping and air traffic lanes safer than the area around Edwards Air Force Base, which in recent years has seen an increase in housing developments and air traffic encroaching on the test range.
"As it turned out, we made a good choice," Brown said yesterday. "This is a high-risk, experimental program, which is why we use an unmanned aircraft and why we use PMRF."
All of the tests have been during the summer months, when there is maximum sunlight and when the runway at the missile range is in the lee of the tradewinds, offering almost dead-calm conditions for both takeoff and landing.
Pathfinder, NASA's first solar airplane, began flying from Kauai in 1997 and played a major role in taking infrared aerial photographs of all of the Hawaiian Islands.
Pathfinder Plus -- the original Pathfinder with additional wing sections and motors -- was tested in 1998 and reached 80,201 feet, a record for propeller-driven aircraft. Pathfinder Plus is still based on Kauai and became last year the first solar airplane to be used for commercial purposes. It was flown over Kauai to take pictures of crops.
As of yesterday, Pathfinder Plus once again became the world's only functional solar airplane.
Helios was a new and much larger aircraft. Like Pathfinder, it was a large flying wing with no fuselage. And like Pathfinder, once airborne its wing tips bowed upward, giving the aircraft a graceful appearance.
Powered by 14 electric 2-horsepower motors turning 79-inch propellers, Helios was built of carbon fiber, graphite epoxy, Kevlar and Styrofoam and covered with a thin, transparent skin. Although its 247-foot wingspan was wider than the wings of a Boeing 747, Helios weighed 1,500 pounds and had a takeoff speed of only 17 mph. Because of the electric motors, it was virtually silent in flight.
Two years ago, Helios set the world sustained level-flight altitude record of 96,863 feet, smashing the old mark of 85,068 feet set by an SR-71 spy plane in 1976.
A large crowd of Kauai residents lined the runway to watch Helios take off on its record flight in 2001. This year, because of increased security at the Navy base, the public was not able to view the Helios tests.
