It will be launchedweather permittingat about 8:30 p.m. August 7 off the rocky shores of St. John's, Newfoundland, where the flyers are stationed at a Royal Canadian Air Force base. The destination is Round Stone bog in Ireland.
The STAR crew said they chose the model plane's route in tribute to the first full-scale Atlantic crossing. In 1919, a Vickers Vimy World War I bomber flown by Royal Air Force pilots John Alcock and Arthur Whitten Brown made a tough landing at Round Stone after crossing the sea from Newfoundland.
After the plane is guided by remote control to a cruising altitude of 500 feet, it will be put on autopilot, to be steered by GPS signals and an onboard microprocessor. Hill said 500 feet is an optimal cruising altitude because "there won't be any airplanes that low or ships that tall, so the path should be clear."
The 11-pound weight limit made fuel capacity a big challenge. The plane's weight is evenly divided between structure and fuel. Shaving ounces off the plane's structural weight was crucial, said team member Roy Day, the former deputy director of NASA's shuttle program. "Every ounce of structure is an ounce of fuel that you cannot carry," he said.
Fuel consumption is a tricky issue. Hill must set the rate of fuel consumption by trickling a "whiskey shot," or two ounces of fuel an hour, through a small hole that can change size because of temperature or humidity. If the plane uses too much fuel per hour, the engine will run fine, but they will run out of fuel. If it uses too little, the engine can stall out, and if it does the plane will crash.
"There's been a lot of effort in modifications to the engine, the fuel system, and the carburetor to get absolutely the best efficiency out of the engine and still have it run reliably," Hill explained. "If the amount of fuel is too small the engine may quit. It's a delicate balance between using as little fuel as possible and still having a reliable engine."
The flight route, of about 1,900 miles (3,057 kilometers) total, is expected to take about 36 hours to complete, but much will depend on head winds and tailwinds.
The plane generally cruises at 42 miles per hour, but tailwinds could boost its speed to 60 mph or more. It can fly in head winds of up to 30 mph, but would burn fuel too fast to make it to the Irish coast.
Because bad weather over the North Atlantic could mean big trouble for such a small craft, Hill and his colleagues have been tracking the weather for three years to aid forecasting. "It determines when we go, and how long it will take," said Hill. "We'll watch for days when we have good weather blowing towards Ireland."
Hill and his STAR team will take four model planes with them to Newfoundland. If they are unable to track the first plane 40 hours after takeoff, they will launch the second one, followed by the others if necessary, until one of them has reached Irelandor until all four have disappeared.
The team is confident that such a complete loss will not happen.
Software expert Joe Foster has been designing and developing the plane's autopilot and navigation systems for four years. The performance of two onboard custom-built computers is crucial to the flight's success. "If we put the right way points in there," says Hill, "and the machine and propeller keep pulling, the steering system will take it where we need it to go."
The crew will track the plane's progress across the Atlantic. "The plane has a transmitter that sends up a burst of information every minute, including its position, altitude, how fast it's traveling, engine rpm, and other control functions," said Hill.
Orbiting communications satellites will receive the information, which team members on both sides of the Atlantic will be able to access.
"Knowing the positions of the plane and its speed, we'll be able to predict it's arrival, so there should be no surprises," said Hill. "When we get to our destination it just goes into a loiter condition."
The plane will circle until the pilot in Ireland, Paul Howey, switches off the automatic system and brings the plane down manually.
On August 11, 2003, model aviation history was made when "The Spirit of Butt's Farm" became the first aeromodel to fly nonstop across the Atlantic Ocean, setting two world records in the process. Read more about it on the TAM Web site.