Right of way?

[Tex Murphy]

Can anyone give me any input on the following situation? - You are on route to your destination (maintaining FL330/.8) and ATC ask you to descend to a non-standard level (FL310) for crossing traffic. After descending you find out the traffic for which you were asked to give way for, is not crossing but overtaking, maintaining the same level on the same route but faster.
It so happens this traffic is going to a destination approximately 300 miles past your own.
Who has the right of way? The way I understand it is that an aircraft maintaining a cruising level is normally given priority over another aircraft asking for that level, or an aircraft at the same level behind it. Any clues?

[Proceed As Cleared]

Tex,

What was your point of dep and dest?
Whose freq where you on?
What was the dest of the other tfc?

You presumably fly A320, correct?

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I just wanted to tell you: We wish you good luck and we're all counting on you.

[Tex Murphy]

Proceed As Cleared,

Departing Paris for Dhahran; talking to Budapest control; and the destination of the other aircraft was Dubai.

[ 30 September 2001: Message edited by: Tex Murphy ]

[ 01 October 2001: Message edited by: Tex Murphy ]

[jjj]

In an overtaking situation like this you certainly have priority. Are you certain that this is what happened. Maybe there was really a crossing aircraft which you were in conflict with but the aircraft following you may not have been in conflict with, hence you had to go down and by the time you were clear of the crossing traffic the aircraft behind had caught you up to much so you had to stay down.

Often there is more than just 2 aircraft to a problem :)

[Avman]

Not so easy to answer not knowing all the facts from ATC's point of view. At our unit if one of two has to go down for seperation purposes we generally go for the aircraft with the shortest distance to go to destination. There's also a good possibility that the traffic that overtook you was at 330 long before you got there. You may both have been on seperate routes initially until converging over or just before Hungary. Budapest accepts you both at 330 and keeps you there until it is necessary to give one of you a level change. You had the shortest distance to go (to dest) so you went down. There may have been other reasons too. I take it you got back to 330 (or higher) again later on.

When a controller has a conflict the solution chosen will be as fair as possible, but it has to take in the entire picture which may involve other traffic and other units' airspace constraints. You only see (and hear) just a small piece of the jigsaw.

[Proceed As Cleared]

Ok Tex,

There are probably different possibilities:

1. There was the three of you at 330, you given descent, the one behind you and the third one (which would have been on a crossing track and you might not have had on your TCAS) on a heading.

2. Assuming that both of you were at 330, the Controller decided to give priority to the tfc whose dest was further away.

As a controller, if you have two acft with same req FL and only one of them can get it, you decide as mentioned above.
It's common sense for us, not a priority thing.
If one of them is already at cruising level and the other req the same FL, but going to a dest further away, you would certainly not descend the one at cruising level to provide the other one with his requested FL.
Generally, Tex, bear in mind, that often we make decisions based on many different factors. We also have to consider tfc not being on our freq yet, certain req from adjacent centres might be also relevant, regulations based on bilateral agreements between centres apply as well.
Therefore something occurring like it did to you might not make too much sense for you as a pilot, but it's in fact a puzzle, you're a part of.
BTW, did you ever visit an ATC unit? Would certainly give you a good idea of how the whole system works.

Cheers

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I just wanted to tell you: We wish you good luck and we're all counting on you.