Following the recent hullabaloo about aircraft landing on fumes I thought an explanation of certain terms would be advantageous to all concerned. Keep in mind that the following is straight from ICAO PANS-ATM (Doc 4444).
Expected approach time. The time at which ATC expects that an arriving aircraft, following a delay, will leave the holding fix to complete its approach for a landing.
Note.— The actual time of leaving the holding fix will depend upon the approach clearance.
6.5.8 Onward clearance time
In the event an aircraft is held en route or at a location or aid other than the initial approach fix, the aircraft concerned shall, as soon as practicable, be given an expected onward clearance time from the holding fix. The aircraft shall also be advised if further holding at a subsequent holding fix is expected.
Note.— “Onward clearance time” is the time at which an aircraft can expect to leave the fix at which it is being held.
Take special note of the following: ”…or aid other than the initial approach fix,…” Now I may not be the world’s smartest person, but there is no way in hell that Desdi and Bubin are Initial Approach Fixes.
Recently a lot of pilots and airlines have been screaming for EATs and ATCOs at the UAE ACC have been instructed to issue EATs to all aircraft expecting a delay of twenty minutes or more. The idea behind this instruction is sound but the application thereof has absolutely no purpose.
Pilots want EATs so they can plan their fuel management but the truth is that UAE ACC
can not issue EATs. This can only be done by an Approach unit for the simple reason that ACC can’t possibly know what is going to happen to the aircraft between the time it leaves the Desdi/Bubin en-route hold, until the time it completes the approach and land. From DESDI to touchdown on Rwy30 is about fifty nautical miles and a hell of a lot can happen in between.
What pilots are actually given when they enter the D/B holds are OCTs (Onward Clearance Times) and not EATs. If you therefore think that you can complete the approach and land at your EAT, you are sorely mistaken as another fifteen to twenty minutes can elapse before you get close to touchdown. Add another XX minutes if you execute a missed approach.
The correct application would be a hold created at the initial approach fix where DXB APP would hold traffic. Once this hold is full traffic will be held en-route at Desdi and Bubin.
Therefore a word of caution. Take any EAT you receive from UAE ACC with a pinch of salt, simply because it isn’t one.