Under Radar Control

[minibus330]

The day before, while under Beijing Control, we were instructed to fly 3 miles LEFT offset due to traffic. We complied. Then a Martinair was instructed to do the same. The Martinair crew refused to do so citing that it was non standard ICAO to fly a left offset. My understanding is that we should comply with the ATC instruction since we are under radar control. If we are flying the NOPAC route, for instance, then we should fly a right offset if required since there is no radar control over the Pacific. Comments?

[Tarq57]

Comment: IMO you responded correctly, the Martinair crew did not. It would seem to me that the controller asking for an offset is just another form of radar control, and a valuable one at that. (The alternative, of course, to specify headings to fly which would amount to the same thing, but in a more workload demanding way, until clear of traffic.)
When not being directly radar controlled, where an offset is approved without ATC reference, it should be to the right.
Just my 2p worth.

[timelapse]

But presumably a track offset would be no more 'deemed separated' than a normal own navigation track.. unless local procedures are different to what I understand.

[Tarq57]

If it was under radar control, the controller would have (hopefully) be monitoring the spacing required. Which although requiring all the normal care, is a bit of a "no-brainer" using a track offset for a flight that is known to have a highly accurate nav system. In practice (or how I or my colleagues would do it) a numerical value a bit higher than the required spacing would be chosen, to allow a comfortable safety margin. Eg: you need 3 miles, you aim for 4. Or 5. Depends on workload/other distractions. If it shrinks a wee bit, doesn't matter.

[Spitoon]

But presumably a track offset would be no more 'deemed separated' than a normal own navigation track..

But is this about deemed separations? I'm an approach/terminal controller so maybe there are some differences in the en-route environment and the related procedures but....

The only separation that matters is the appropriate radar separation (in my world, that's usually 3NM) and my job is to make sure the aeroplanes don't get any closer than that. As long as I do that the bosses don't bother me - and, broadly speaking, the bosses don't care how I do it. Getting my controller licence and certificate of competence, hopefully, has equipped me with a wide repertoire of control techniques to do the job. I can tell aircraft to fly a route, heading, radial, I can let them fly on their own nav, whatever....just as long as I get 3NM between them. An offset track seems fine to me. An opposite direction ofset is fine too. And I'll watch it on radar to make sure I get my radar sparation.

Having said all that, good practice - and a few years experience - tells me that having aeroplanes that will be close to the separation minimum on anything but assigned headings increases the chances of the bosses wanting to talk to me because there are too many variables that I cannot control in the equation.

[minibus330]

Knowledge is power ... provided we apply it correctly and intelligently.
I also thought that the offset is another form of radar controlled separation which will keep the conflicting traffic parallelly separated by a known distance. This is safer and would relief the controller of continually giving heading instructions to the pilots, especially so in a country where English is not widely spoken.
The Chinese controller could have instructed the Martinair crew to make a right hand orbit if he was nasty enough. Hehe.

[Diddley Dee]

I'm on a break whilst on duty providing radar control all evening. If I gave someone a vector under RC and the captian declined to take the control instruction without a very good reason. I would move the conflicting traffic out of his way and ask for a relief so I could file against him.
Radar Control takes precedence over rules of the air such as each altering course to the right IMHO.

And no, I am not a filer by nature, been controlling 17 years and have never filed against a pilot.

DD

[Spitoon]

If I gave someone a vector under RC and the captian declined to take the control instruction without a very good reason. I would move the conflicting traffic out of his way and ask for a relief so I could file against him

File what? On what grounds?

Last time I looked a pilot could always decline any clearance (and a vector is just a clearance. Good job you're not a filer by nature!

[minibus330]

In this case, I don't think it was right of the Matinair crew to reject the ATC instruction. He obviously has his idea of "standard ICAO procedures" all wrongly applied. I complied with ATC's instruction to fly 3 miles left offset as I was radar monitored. The Martinair crew did not want to fly the left offset (citing the ICAO standard procedures) but insisted that it should be a right offset instead. This obviously will bring it into conflict with my aircraft.
I would understand if it was due to weather that they have refused to deviate to the left, but the weather was fine. This is a case of wrong applied knowledge.
If the Martinair crew has been given the instruction first and refused to comply, the delay in initiating the deviation could have caused a mishap. If he was aware of the traffic situation he would have heard ATC giving out the instruction (in English) to us first and realised that there was conflicting traffic ahead.
I believe ATC and pilots alike are entitled to file reports if safety is compromised or jeopardised by either party's actions. If one has valid reasons for his actions there is nothing to fear. Sometimes miscommunications do occur. An apology goes a long way in easing tensions or misunderstanding between ATC and pilots. Neither party wants a mishap.

[slatch]

Well, luckily most ATCO's dont file when an aircraft makes a mistake. The ones that do normally learn that having their actions as well as the concerned aircrafts actions looked at makes trouble for both. But guidelines from experiance, when in Radar do what the controller instructs, within aircraft capabilities of course, and unless faced with an RA, then follow the RA, the controller has already had his try and failed. So when in radar contact offset where and how instructed, non radar (SLOP) right and you dont even have to tell. When you show back up on Radar you are still within RNP conformace. Once Radar identified request further offset or gently head back on track. Remember seeing you are coming from non radar to radar you are at least 30 miles from any traffic ATC could normally care less about a 1 or 2 mile non radar offset.

[Diddley Dee]

Spitoon

I am confused. The original post was headed with radar control not RIS or RAS etc. I take that to mean the ac in question was inside CAS and under a radar control service ie all instructions are mandatory. Are you suggesting that instructions to seperate ac under RC are in fact advisory and may be declined on the basis of issues like each ac to turn to the right rule?

I compltely understand & agree a captain is responsible for the safety of an ac but to refuse to comply with a radar control instruction as was described, seems completely at odds with the whole concept of RC & how it is applied.

DD