Emergency Help Devices - EPIRB/PLB, Sat Phone, SPOT, etc [sp
Posted: Tue 06 Jan, 2009 1:20 pm
Just to check on real life differences between a PLB with GPS and without I sent an email to AMSA with the following reply(submitted with permission from Linda)
Quote...
Hi Vern,
Your enquiry has been forwarded to myself to respond as I receive these enquiries everyday.
The best accuracy the Cospas-Sarsat satellite system can relay is 120mtrs. The GPS chip inside the beacon may have an accuracy of 45/60/100 mtrs etc. however when the system receives the distress message and relays it the accuracy is 120mtrs. This is very good compared to the analogue system of 20kms.
Non GPS equipped distress beacons the accuracy is a 5km circular radius.
We do recommend the GPS equipped distress beacons however they are a higher cost. When a GPS beacon is activated it is detected within a few minutes, the RCC will receive the HEX ID and the GPS coordinates within 120mtrs.
When a Non-GPS beacon is detected within a few minutes the RCC will receive the HEX ID but no position details. The position is calculated by a Polar Orbiting satellite which averages an overpass over the Australian SAR region every 90mins or max. 5hrs. When the first position report is received we receive two positions; A and B. One is the true position and the other is the mirror image. To confirm which is the true position we can await for the satellite to overpass a second time or an overflying aircraft may report into air traffic control the hearing of 121.5 MHz in a particular area or the emergency contacts can provide information as to the region the owner is operating in.
In order to deploy a search & rescue platform or personnel we require the location/area/region of the distress. The sooner we know the location of the distress the quicker we can organise the rescue deployment. A GPS equipped beacon is the quickest way to advise the RCC of the location of distress. Please note even though the distress alert is received within a few minutes, it can take some time to coordinate a rescue platform, this can be affected or delayed by; day or night, weather conditions, strong winds, fog, low cloud, helicopter/vessel/personnel availability to respond in the area etc. It is important the person in distress maintains there survivability until the rescue crew are on scene.
Remember: Do not turn the beacon off until the rescue crew advise to do so, just because you may see the rescue crew in the vicinity does not mean that they have seen you.
If you wish to discuss further please contact me, I'm happy to assist with any enquiries or product details.
One thing I forgot to mention is that when a beacon is detected we always contact the owner and then the emergency contacts immediately to confirm if it is an inadvertent activation or a live distress. If the owner answers the phone it is usually a false alarm of which we request the owner to locate the beacon and switch off.
If a beacon owner feels that the beacon may have inadvertently activated they can call the RCC directly on Ph: 1800 641 792. There is no penalty, we appreciate the call to confirm all is safe & well.
Regards,
Linda Berryman
406 MHz / MMSI DATABASE MANAGER
PLANNING & BUSINESS SUPPORT
EMERGENCY RESPONSE DIVISION
Level 3, 25 Constitution Avenue, Canberra ACT 2601
GPO Box 2181, Canberra ACT 2601
p +61 (0)2 6279 5041 or 1800 406 406
f +61 (0)2 9332 6323 or 1800 406 329
e linda.berryman@amsa.gov.au
w http://www.amsa.gov.au
GET A BETTER FIX WITH 406
Distress Beacon Information & Advice
e ausbeacon@amsa.gov.au
w http://www.amsa.gov.au/beacons
Online Beacon Registration
w http://www.beacons.amsa.gov.au
MMSI & VHF-DSC Information
w http://www.amsa.gov.au/mmsi
Quote...
Hi Vern,
Your enquiry has been forwarded to myself to respond as I receive these enquiries everyday.
The best accuracy the Cospas-Sarsat satellite system can relay is 120mtrs. The GPS chip inside the beacon may have an accuracy of 45/60/100 mtrs etc. however when the system receives the distress message and relays it the accuracy is 120mtrs. This is very good compared to the analogue system of 20kms.
Non GPS equipped distress beacons the accuracy is a 5km circular radius.
We do recommend the GPS equipped distress beacons however they are a higher cost. When a GPS beacon is activated it is detected within a few minutes, the RCC will receive the HEX ID and the GPS coordinates within 120mtrs.
When a Non-GPS beacon is detected within a few minutes the RCC will receive the HEX ID but no position details. The position is calculated by a Polar Orbiting satellite which averages an overpass over the Australian SAR region every 90mins or max. 5hrs. When the first position report is received we receive two positions; A and B. One is the true position and the other is the mirror image. To confirm which is the true position we can await for the satellite to overpass a second time or an overflying aircraft may report into air traffic control the hearing of 121.5 MHz in a particular area or the emergency contacts can provide information as to the region the owner is operating in.
In order to deploy a search & rescue platform or personnel we require the location/area/region of the distress. The sooner we know the location of the distress the quicker we can organise the rescue deployment. A GPS equipped beacon is the quickest way to advise the RCC of the location of distress. Please note even though the distress alert is received within a few minutes, it can take some time to coordinate a rescue platform, this can be affected or delayed by; day or night, weather conditions, strong winds, fog, low cloud, helicopter/vessel/personnel availability to respond in the area etc. It is important the person in distress maintains there survivability until the rescue crew are on scene.
Remember: Do not turn the beacon off until the rescue crew advise to do so, just because you may see the rescue crew in the vicinity does not mean that they have seen you.
If you wish to discuss further please contact me, I'm happy to assist with any enquiries or product details.
One thing I forgot to mention is that when a beacon is detected we always contact the owner and then the emergency contacts immediately to confirm if it is an inadvertent activation or a live distress. If the owner answers the phone it is usually a false alarm of which we request the owner to locate the beacon and switch off.
If a beacon owner feels that the beacon may have inadvertently activated they can call the RCC directly on Ph: 1800 641 792. There is no penalty, we appreciate the call to confirm all is safe & well.
Regards,
Linda Berryman
406 MHz / MMSI DATABASE MANAGER
PLANNING & BUSINESS SUPPORT
EMERGENCY RESPONSE DIVISION
Level 3, 25 Constitution Avenue, Canberra ACT 2601
GPO Box 2181, Canberra ACT 2601
p +61 (0)2 6279 5041 or 1800 406 406
f +61 (0)2 9332 6323 or 1800 406 329
e linda.berryman@amsa.gov.au
w http://www.amsa.gov.au
GET A BETTER FIX WITH 406
Distress Beacon Information & Advice
e ausbeacon@amsa.gov.au
w http://www.amsa.gov.au/beacons
Online Beacon Registration
w http://www.beacons.amsa.gov.au
MMSI & VHF-DSC Information
w http://www.amsa.gov.au/mmsi