Shemya cross-check even if in radar contact?
Thread Starter
Join Date: Jul 2000
Location: West
Posts: 399
Likes: 0
Received 0 Likes
on
0 Posts
Shemya cross-check even if in radar contact?
I have always accomplished the Shemya cross-check because the chart says it is required. Now I am hearing (unofficially so far) that it is only necessary if not in radar contact.
Is there a source document for this?
What are your thoughts?
Is there a source document for this?
What are your thoughts?
...and which chart says it is required? 
Mr. None, I think you are on the wrong forum, old chap. Maybe you should cross-check your PPRuNE posting!
For those asking, Shemya is a god-forsaken island in the Aleutian chain. After the shootdown of Korean Air 007 by a Soviet fighter, it is suspected that the B747 crew departed Anchorage for Seoul in 'heading' mode on the autopilot and left it there; the primitive nav system still sequenced its waypoints so the aircraft drifted off track into the bad guys' airspace.
The crosscheck was a requirement to check raw data distance abeam Shemya VOR to ensure that the correct NOPAC (North Pacific) track was being flown. For those blindly following green or magenta lines or GPS, the lessons of this incident apply today.
If you look at the first letters of the waypoints of the parallel NOPAC tracks system from north to south, they spell NOPAC! Riveting stuff, eh?
For those asking, Shemya is a god-forsaken island in the Aleutian chain. After the shootdown of Korean Air 007 by a Soviet fighter, it is suspected that the B747 crew departed Anchorage for Seoul in 'heading' mode on the autopilot and left it there; the primitive nav system still sequenced its waypoints so the aircraft drifted off track into the bad guys' airspace.
The crosscheck was a requirement to check raw data distance abeam Shemya VOR to ensure that the correct NOPAC (North Pacific) track was being flown. For those blindly following green or magenta lines or GPS, the lessons of this incident apply today.
If you look at the first letters of the waypoints of the parallel NOPAC tracks system from north to south, they spell NOPAC! Riveting stuff, eh?
Last edited by Captain Dart; 7th Mar 2011 at 00:09.
