SAR S-92 Missing Ireland
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Originally Posted by [email protected]
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Dclbydaplha - so it is S-AIS
The original concept of AIS was a LOS collision avoidance IIRC.
Dclbydaplha - so it is S-AIS
The original concept of AIS was a LOS collision avoidance IIRC.Your recollection is correct, IIRC it was originally developed for collision avoidance in coastal approaches and in to harbour. Like all technology its use gets extended. I am not aware of any modification required to a ship's AIS for it to be tracked by satellite. Best if it is a Class A unit though.
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Concentric
I don't know the SAR fit for that S92, but I'd be surprised if it didn't include AIS. However whether it would have been selected for display is another matter.
Again, even with a beacon, the crew would have needed to be operating the radar in a beacon mode to benefit.
Not sure what the SOP would have been with regards to those items during such an approach.
I don't know the SAR fit for that S92, but I'd be surprised if it didn't include AIS. However whether it would have been selected for display is another matter.
Again, even with a beacon, the crew would have needed to be operating the radar in a beacon mode to benefit.
Not sure what the SOP would have been with regards to those items during such an approach.
My experience out of long time hosting of VHF AIS RX that standard coverage is 40 km between the islands. On open 80-100 km (LOS) for small crafts and in some extra summer propagation cases can go up 1500-1800 km. Location Mediterranean sea.
For low flying objects much better than ADS B or Mode A & C MLAT (have them too)
For low flying objects much better than ADS B or Mode A & C MLAT (have them too)
Page 17: http://skybrary.aero/bookshelf/books/3018.pdf
The MK XXII uses turn
rate and direction to predict the aircraft flight path in the turn
and “looks around the corner” for terrain/obstacles. Forward
airspeed will also modify the look-ahead envelope. Below 100
knots, the envelope is reduced until it is completely inhibited at
70 knots or less. The preceeding speeds are for "fast" helicopter
configurations, "slow" configurations use the range 90 knots to
60 knots for envelope reduction
rate and direction to predict the aircraft flight path in the turn
and “looks around the corner” for terrain/obstacles. Forward
airspeed will also modify the look-ahead envelope. Below 100
knots, the envelope is reduced until it is completely inhibited at
70 knots or less. The preceeding speeds are for "fast" helicopter
configurations, "slow" configurations use the range 90 knots to
60 knots for envelope reduction
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The following link may be of interest. Irish Coast uard is part of Dept. of Transport
S-92A Technical Details | DTTAS Department of Transport, Tourism And Sport
S-92A Technical Details | DTTAS Department of Transport, Tourism And Sport
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Just to note. The R4a is not connected to any on board sensors (ie air data computers) so any speed data is calculated from the AIS internal GPS position changes. The AIS GPS antenna on the S92 is located on the tail pylon.
I am not aware of any modification required to a ship's AIS for it to be tracked by satellite. Best if it is a Class A unit though.
The AIS GPS antenna on the S92 is located on the tail pylon.
Great idea to have the EGPWS disabled at 70 kts - just the sort of speed you are doing a trans down to the hover and possibly getting close to obstacles/land.
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212 man. Sorry being a bit sloppy with my terminology. There are a number of conditions under which there is no FLTA protection. Similarly warnings could be inhibited. However the display should have had an unambiguous amber blob of terrain in their flight path. I can't fathom either the absence or misinterpretation of this.
I have come to the conclusion the system can't be relied upon 100% of the time, and if you're relying on it not to hit something, that reliance is not totally reliable.
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Originally Posted by [email protected]
No, I believe the modifications had to be done to the satellites to allow them to pick up the specific VHF tx from the ships AIS - duplex channels of 87B and 88B I think.
that will be the GPS Rx but where is the VHF Tx aerial for the AIS?
Great idea to have the EGPWS disabled at 70 kts - just the sort of speed you are doing a trans down to the hover and possibly getting close to obstacles/land.
that will be the GPS Rx but where is the VHF Tx aerial for the AIS?
Great idea to have the EGPWS disabled at 70 kts - just the sort of speed you are doing a trans down to the hover and possibly getting close to obstacles/land.
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Originally Posted by [email protected]
Great idea to have the EGPWS disabled at 70 kts - just the sort of speed you are doing a trans down to the hover and possibly getting close to obstacles/land.
As far as I can tell, the map display should still have had the high terrain marked. If it wasn't i'm interested to know why.
As far as I can tell, the map display should still have had the high terrain marked. If it wasn't i'm interested to know why
Yes, but assuming the wx radar is on the NAV MFD it will require the PFD to be set to ARC mode to show EGPWS (or vice versa depending on which requires the greater granularity) . That's how I set it up, but some operators like to revert to HSI mode for that nostalgic feeling of reduced SA.....
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Thanks for the info, from your setup I presume there is no automatic popup with proximity to off airport terrain.
There is a pop-up mode which will appear on an MFD with PFD Arc or NAV set and, if none selected as such, will automatically change the display of one MFD according to a priority logic. However, I prefer to have the map there in the first place to avoid pop-ups!
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The pop up mode is not a separate mode, it merely displays the terrain map when a warning is generated; so it will be suppressed in the same way as described above.
On another note, radar beacons display in the S-92A standard wx mode.
On another note, radar beacons display in the S-92A standard wx mode.