Technologically these are very interesting aircraft. The idea is to have an airplane that can stay aloft for months at a time. Obviously it cannot be manned, but given automated control systems and suitable payload equipment, these vehicles can perform a wide array of tasks. One task is clearly spying, that is, being able to observe and take pictures of people or objects on the ground.
'Eternal planes' to watch over us (By Jo Twist, BBC News science and technology reporter, Tuesday, 2 August 2005)
My previous coverage:
- Aerovironment tests a hydrogen powered airplane
- High Altitude Surveillance Aircraft
- Electric airplane (UAV) stays aloft for 48 hours
- UAV's coming to the U.S. for more spying on U.S. Citizens
The BBC article discusses an airplane being built by the British company, QinetiQ. It is similar to the recent airplane designed by Aerovironment in that it uses Lithium batteries to store electricity rather than a fuel cell system. The British development project is named "Mercator". It's clear this is a prototype, and hasn't even completed a long running flight:
Based on computer modelling, the craft QinetiQ has developed thus far could complete a day-night cycle. It would use solar power during the day, while recharging the batteries, which would then provide enough "juice" to fly at night.
It seems straightforward, but it is only the improved efficiencies in solar cell and battery technologies, even over the last year, that has made this at all possible.
"The key technologies are solar cells and batteries. Battery technology is receiving billions worldwide and it is a very rapidly evolving technology," says Dr Rogoyski.
... Initial tests on a 40% scale model of the QinetiQ Mercator UAV have proved successful.
"The technology we have right now will enable us to stay up in the air for 60 hours, but we will not be trying that tomorrow," says Dr Davey. "Trials are planned for next year."