I faintly remember reading or hearing something about ELTs needing enough of an impact to set them off, and that a lesser impact won't set them off and they may need to be turned on manually.
Does anyone know if this is true?
Also, if the ELB is in some sort of trench or canyon, I am assuming that this could severely limit access to satellites?
The problem, even with the latest generation ELTs is that they are too easily set off. This why even a moderately hard landing can set them off. If a landing is soft enough not to set off the ELT's G switch, it's unlikely to damage the pilot and pax.
Having said that, they all do have a manually activated switch. They also have innumerable ways to fail, which is why they are so unreliable.
PLBs will work fine as long as they have a modest view of the sky. We have tested them in pretty narrow and deep canyons and gorges. They may not get a GPS fix, if they are so equipped, and they may not get to the Geostationary satellite (though often the signal reflected off canyon walls will still do so), but the Low Earth Orbiting (LEO) satellites will eventually get a Doppler location over a matter of just a few hours max and depending upon geometry and timing, possibly within 20-30 minutes.
Previous Topic
Index
