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Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
The Black Hornet PD1200 surveillance micro-copter has 100mm (4") rotor blades, weighs just 15g, and can fly at speeds up to 30km/hr.
The manufacturers claim the helicopter can be carried in a pocket and launched within seconds to give an instant aerial view of military, 'national security', or safety situations.
(As well as snooping through the bedroom windows of The World and His Wife! )
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
I would guess it is remotely flown by a computer.... and that each one costs a tidy fortune. Horrible though it is, it is in its way a marvel of engineering, made with the skills of a watchmaker, I suppose.
Registered Member #1232
Joined: Wed Jan 16 2008, 10:53PM
Location: Doon tha Toon!
Posts: 881
You can buy little toy helicopters that are infra-red controlled from toy-stalls in the shopping malls up here for about £20.
They are a bitch to fly but they make a fun gift for someone and at that price you can't go far wrong! Just don't try flying it outside as the sunlight seems to block its communication. A mate of mine tried it, despite "indoor use only" on the box. It refused to take off several times then took off and continued upwards out of sight forever! :(
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
I didn't know that Geordie - but one of these things has a payload of Tv camera and GPS etc, so I bet they cost a small fortune to meet a military specification.
Registered Member #16
Joined: Thu Feb 02 2006, 02:22PM
Location: New Wilmington, PA
Posts: 554
Weight has a lot less to do with the ability to fly in high wind than prop speed does. I fly an E-flight Blade MCX. It has a low prop speed, and isn't capable of flying in even a slight breeze. Its big brother weighs a bit less than twice as much, but has a rotor speed more than double the MCX, and can quite happily putter along in a 10mph wind.
Really its all about the rotor's speed in relation to the wind its encountering, and the rotor's air output compared to the wind acting on the helicopter body, not how far a given wind speed can fling a ball of paper the same weight as the helicopter.
Registered Member #1911
Joined: Mon Jan 05 2009, 06:30PM
Location: Salem, Oregon, USA
Posts: 165
Dave Marshall wrote ...
[snip]
Really its all about the rotor's speed in relation to the wind its encountering, and the rotor's air output compared to the wind acting on the helicopter body, not how far a given wind speed can fling a ball of paper the same weight as the helicopter.
-Dave
That is a good point; the gyroscopic forces do have a great deal of influence in the aircraft's stability, and once the aircraft is off the ground, it should be able to stay in the air if it has enough gyroscopic force and a fair pilot to right it when he sees it being pushed by the wind.
Here's a good question - If we can get these little hobby helicopters off the ground with pager motors, why can't we get scaled up versions off the ground with some real, heavy-duty motors and larger batteries? There would be greater efficiency and the ability to use hollow materials for the chassis construction, making the weight to power output ratio even better for us. Am I missing something extremely crucial?
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Black Hornet PD1200 micro-copter
