Bit of a strange one. We are visiting family in Meath and as we passed through Slane just now we observed what seemed to be a group of 20 - 30 helium balloons that someone has obviously released. I assume these would be a danger to avaiation. Is there anyone I can contact to warn of the danger? I'm not even sure how I could give them a location only they seemed to be heading East.
You could contact the IAA, but ultimately it's a few balloons in a very big sky. The chances of them hitting anything (or even being detected) are extremely small.
I think Met Eireann are the only body officially allowed to launch balloons. I toyed with the idea of high-altitude sounding balloons (with a camera aboard) a while back, but it wasn't legal here.
10. (1) A person shall not cause or permit a group of small balloons exceeding
1000 in number to be simultaneously released at a single site wholly or
partly within the aerodrome traffic zone of an aerodrome or exceeding
2000 in number at any place within the State without the permission in
writing of the Authority and other than in accordance with any
conditions subject to which that permission may have been granted.
4
(2) For the purposes of this Article “simultaneously released at a single site”
shall mean the release of a specified number of balloons during a period
not exceeding 15 minutes from within an area not exceeding 1 kilometre
square.
(3) An unmanned free balloon which exceeds two metres in any linear
dimension at any stage in its flight, other than a balloon used by the
Meteorological Services for the purposes of upper air observations, shall
not be flown by any person within the State without the permission in
writing of the Authority and other than in accordance with any
conditions subject to which that permission may have been granted.
can you achieve anything with a balloon less than 2 metres?
The issue is the "at any stage in its flight" part of the SI above. As the balloon rises and the local air pressure drops, the balloon diameter increases until it eventually pops. To keep below the 2m limit, it must be much smaller than this at sea level.
Sounding balloons are roughly 2m in diameter when filled, and can lift a small camera, transponder etc.
