An aerial view of an island in Barai Lake, near Angor Wat shows

a small temple ruin along with a latter-day house (foreground).

Even at the height of his power Jayavarman VII did not have a view of Angkor like

this. Swooping around Borei Lake, people look up and wave at a tiny 50 hp plane carrying

out low altitude surveying, a camera fixed to its wing.

"You get into the environment," says Donald Cooney, pilot of the 185 kilogram,

two-seater ultralite. "It's like being on the waves of the ocean when you're

bodysurfing."

The ultralite plane survey is part of the Greater Angkor Project, carrying out archaeological

research between the Apsara Authority, France's Ecole Francaise d' Extréme-Orient

(EFEO), and the University of Sydney.

The Greater Angkor Project aims to study the relationship between the extent of the

urban complex of Angkor and the demise of the city, mixing archaeology and earth

sciences. The trike, a plane with a hang-glider wing and three-wheeled base, may

make the job easier.

"As far as we know, no one has used ultralites for academic work such as this

in such a serious ongoing way," says survey coordinator Ian Brookes.

NASA radar imaging conducted in September 2000 shows the ancient city of Angkor spanned

1,000 square kilometers, much larger than expected. Banteay Srey is now thought to

be at its northern edge instead of a separate settlement.

As people moved to the slopes of the Kulen ranges, the theory goes, they cleared

forests for agriculture, causing soil erosion. The resulting sediment from flooding

could have damaged the canal network and affected fish reproduction.

"What is critically important is that the same process of ecological deterioration

may be starting again," says Professor Roland Fletcher, director of the Greater

Angkor Project. "The past may therefore be a crucial clue to the future."

The ultralite survey will provide low altitude "ground truthing" on the

data provided by NASA. Checking on features such as vegetation types and canals from

the ground is time consuming and often dangerous.

"Anti-personnel mines are a potential threat and make fieldwork on the ground

problematic, especially in the northern half of Angkor," says Fletcher. "Low

altitude aerial survey is a dream come true as it solves all those problems."

The idea to use an ultralite airplane developed last year when Cooney was on vacation

in Siem Reap with his partner, Alexandra Rosen, now the survey's administrator. Sitting

next to Brookes in a restaurant, Rosen overheard him talking about his involvement

in the Greater Angkor Project.

Rosen and Cooney, who has been flying trikes for 20 years, manufactures them and

competes in international competitions, offered to supply a plane. It then took a

year to organize and get approval for the project before the first flight April 5.

"All said and done, it's been a very, very fast project development and implementation,"

says Brookes.

Due to the difficulty of field investigation, there is a tradition of using flight

in the interest of Angkorian archaeology. It started long before the space shuttle

provided images in 1994.

"They've been doing remote sensing in Cambodia since 1929," says EFEO's

Christophe Pottier. "It's very efficient."

Through remote sensing, the number of known temple remains increased from 250 to

550 in 1998. Pottier proved that people living in housemounds were scattered across

the southern half of the city.

"The north area is next, but it's very slow work," he says.

Pottier is cautiously optimistic about the ultralite survey, saying its results have

yet to be examined. He concedes, however, that low flying "can find detailed

configurations" which make it "much easier to understand the organization

of sites".

Without analyzing the data, members of the survey say many features are evident with

the unique view of the country. They also note the high amount of garbage around

Banteay Srey, and say air pollution affects photography and visibility.

The members of the survey also created a stir in the community, especially at the

rice paddy they use as a landing strip for re-supplying. Villagers have now become

more accustomed to the sight of the low flying plane. A woman in a boat once threw

a fish at them as they passed by.

"It didn't hit us," says Cooney. "She was laughing."

At the end of April, the plane and equipment were stored away in a shipping container

for the wet season. Flights will likely resume in October, and the project is scheduled

to run to 2005.

"This season was a test to ensure that we could fly the plane safely and obtain

results," says Fletcher.

In the future, he hopes to mount two more cameras on to the plane to achieve a three

dimensional view. He also hopes to get a comprehensive view of the region's temples

and do a study of the coastal bars and swamps down the east coast of the Tonle Sap.