Off set tracking
And to stay with it the following article was also posted by me on PPRUNE many many moons ago, so why don't we start it up again and see what we can achieve!
The recent mid-air between a Kazahk Il-76 and a Saudia 747 highlights a concern which we have been discussing between ourselves for months. While all the details may not apply; this disaster does dramatically illustrate
our concern.
The modern onboard GPS and/or DME updated IRS/INS navigational equipment has greatly enhanced the ease and accuracy of aircraft navigation. However, under certain circumstances, this accuracy could become a flight safety hazard.
Airline pilots spent untold hours EXACTLY in the centre of their 10 mile wide airways guaranteed only 1000 or 2000 feet separation from opposite direction traffic.
If there is a mistake during an altitude change by the crew of either aircraft, by the controller, with the communication between the two, or an autoflight equipment failure -- a disaster may occur..
FMS navigation computers should be off set just 1 or 2 miles to the right of track. This would guarantee 2 to 4 miles lateral separation between opposite
direction traffic while all aircraft would still remain well within airways.
This would utilise the extreme accuracy of onboard navigational systems to both remain within airways and to provide additional traffic separation.
Had both aircraft been equipped with TCAS, the Delhi disaster would have been prevented. However, all aircraft world-wide are not so equipped.
Airline pilots almost daily will pass another aircraft with this 1000 feet clearance. Wouldn't it be much safer to also have at least 2 miles lateral seperation? Since equipment and people do fail, why not implement this fail-safe technique?