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Vanblair
22nd Oct 2012, 21:35
Flying VFR in a SEP class G airspace under basic service! I've twice in 2 months received
Traffic 12 o'clock same height reciprocal heading.

On both occasions, I've seen the traffic shortly after and decided there was enough difference in altitude so there was no danger of collision if we both maintained course.

Rules of the air suggest an immediate right turn to avoid a collision, (by both pilots?) but in one of these cases, this would have put me directly in the path of the other a/c which passed perhaps 1/2 mile to my right.

Any advice/comments?

360BakTrak
23rd Oct 2012, 06:35
VFR in class G.....get as high as you can and keep your eyes on stalks!! Those of your pax too!!

What level were you at? I always get as high as I can to avoid the majority of GA traffic around the 2500' area.

Vanblair
23rd Oct 2012, 06:40
2700, solo and 3500 with an instructor
On 2nd occasion I saw the traffic immediately, low at11 o'clock
Instructor requested a left turn so he could see traffic?

Not Long Now
23rd Oct 2012, 07:56
You were lucky to have received the traffic information, and it is 100% up to you to decide to act on it or not, and equally anything you do is entirely up to you. As you say, any avoiding action you decide on might well induce more conflicting traffic, but that's the whole point of class G, it's all up to you.
Mildly muddled 'advice' issued at my unit...(pardon me for paraphrasing, I don't have it to hand, but) for basic service, DO pass traffic if you believe it constitutes a definite risk of collision and you see it, but DO NOT routinely provide a higher service, i.e. traffic, than that notified as this may confuse pilots. For traffic service pass traffic on pertinent traffic only (well obviously??).

orgASMic
23rd Oct 2012, 08:12
You were VFR, but were you obeying the RH traffic rule?

Was the reciprocal traffic following the same line feature but not obeying the RH traffic rule?

Were you in the GA death zone of 'just below the TA', as 360BakTrak suggests?

The more info you give us, the greater the relevance of the advice.

DeeCee
23rd Oct 2012, 08:19
Sometimes you will receive a helpful 'extra' like this if there is a perceived threat. However, only when visual can you decide what action (if any) to take. The 'turn right' action would be if you were head on with another aeroplane.

Andy Mayes
23rd Oct 2012, 09:12
It is clear the traffic has been supplied by a Radar Controller:

Traffic 12 o'clock same height reciprocal heading.

Therefore, should the service not be temporarily 'upgraded' to a Traffic Service then downgraded back to a Basic Service after the traffic had been called?

Avoiding_Action
23rd Oct 2012, 09:34
No need to upgrade.
Pilots should not expect any form of traffic information from a controller, as there is
no such obligation placed on the controller under a Basic Service outside an
Aerodrome Traffic Zone (ATZ), and the pilot remains responsible for collision
avoidance at all times. However, on initial contact the controller may provide traffic
information in general terms to assist with the pilot’s situational awareness. This will
not normally be updated by the controller unless the situation has changed markedly,
or the pilot requests an update. A controller with access to surveillance derived
information shall avoid the routine provision of traffic information on specific aircraft,
and a pilot who considers that he requires such a regular flow of specific traffic
information shall request a Traffic Service. However, if a controller considers that a
definite risk of collision exists, a warning may be issued to the pilot.

2 sheds
23rd Oct 2012, 10:09
Vanblair
The traffic information was "called" to you, albeit under a BS, because the information available to the controller was that there was a risk of collision - possibly based on unvalidated Mode C data (or no Mode C at all). Taking into account the possible error, plus the accepted tolerance, plus the potential for either or both aircraft to change level imminently by a couple of hundred feet, you can see that once you sight that traffic it might well be - in your judgement only, of course - sufficiently clear of you vertically. As regards the opposite direction avoiding action as required by the rules of the air, remember that any radar has a certain tolerance and you cannot infer that traffic reported at 12 o'clock will require both aircraft to turn right - the avoiding action has to be based on your visual perception, or your guess at what might be sensible if you do not have the traffic in sight.

2 s

Spitoon
23rd Oct 2012, 10:52
Rules of the air suggest an immediate right turn to avoid a collision, (by both pilots?) but in one of these cases, this would have put me directly in the path of the other a/c which passed perhaps 1/2 mile to my right.Read the other rules about VFR in class G.