ATC IssuesA place where pilots may enter the 'lions den' that is Air Traffic Control in complete safety and find out the answers to all those obscure topics which you always wanted to know the answer to but were afraid to ask.
I flew VFR into a Class D area not long ago. I was not only informed of IFR traffic nearby, I was specifically asked to turn away from it for "separation" even though I had it in sight and can self-separate.
I had no objections to this in principle (big thanks for keeping me safe !!) but why not change your airspace classification to Class C next time to more accurately reflect what you actually do?
Because providing full radar separation (typically 3nm/1000') between IFR and VFR would be unnecessarily restrictive. With class D we can build in a safety margin where prudent, eg. so that an airliner does not have its TCAS triggered (the other side of the coin to you being happy to self-separate), while allowing far less than 3nm/1000' where possible. There is a passage in CAP 493 that deals with this, I'll look it up later when I have a minute.
Last edited by Roadrunner Once; 28th May 2012 at 17:15.
I was specifically asked to turn away from it for "separation" even though I had it in sight and can self-separate
The 'deconfliction malaise' of VFR in UK Class D is widespread. It is compounded by TCAS RAs, the 'Duty Of Care' advice in CAP774 and deluded, non-flying ATC examiners who autonomously preach so called 'best practice'. Anywhere in particular?
Because providing full radar separation (typically 3nm/1000') between IFR and VFR would be unnecessarily restrictive
Yeah I agree, but this was what I read for separation standards in the Class C area:
Separate VFR aircraft from IFR aircraft by any one of the following: a. Visual separation as specified in para 7-2-1, Visual Separation, para 7-4-2, Vectors for Visual Approach, and para 7-6-7, Sequencing. b. 500 feet vertical separation; c. Target resolution.
Last edited by soaringhigh650; 28th May 2012 at 17:37.
A few possibilities come to mind like if you were in a TRSA (http://www.faa.gov/air_traffic/publi...c/atc0707.html) or if you were talking to controller who is required by LOA to provide basic radar service e.g. sequencing (http://www.faa.gov/air_traffic/publi...c/atc0706.html). This is of course assuming you told the controller you had the traffic in sight (a lot of controllers are good and predicting the future, but we can't read minds). But more often then on not what it comes down to is nobody wants to watch two planes come together. I've learned 2nd hand that the litigation that follows a crash is horrendous. You can either say "fly heading 360 for traffic" once or spend the next 5-10 years in courtrooms and giving depositions saying "there's no separation requirement to VFR's in class D airspace".
Working in Class D I tend to over control slightly as it's not worth the hassle to leave it at traffic information. A few times I have had the following scenario occur- Me: There's 2 737s on final, one at 2 miles, one at 8 miles, are you visual with number 2? A/c: Affirm Me: roger, route behind the second 737 caution wake turbulence blah blah A/c reads it back
What does he do? Starts to route through final approach cutting in front of number 2 before I have to turn him back for another go.
Granted this does not happen for every transit however this has caused me to become cautious and find TI just does not suffice.
No, I was in Twr at the time and the transit was passed from radar as both 737s were on my frequency. I couldn't see the transit as he was a few miles out therefore I could not use reduced sep in the vicinity and had to rely on TI for the cross and monitored on the ATM. He did report visual with both. The second time this happened the inbound traffic had TCAS RA, go around, paperwork! I'm all for VFR pilots taking their own separation but situations like this have left me feeling uncomfortable when there's a few on approach and the pilot reports he's visual with all a/c.
3 Control of VFR Flights 3.1 The minimum services provided to VFR flights in Class D airspace are specified at Section 1, Chapter 2, paragraph 2. Separation standards are not prescribed for application by ATC between VFR flights or between VFR and IFR flights in Class D airspace. However, ATC has a responsibility to prevent collisions between known flights and to maintain a safe, orderly and expeditious flow of traffic. This objective is met by passing sufficient traffic information and instructions to assist pilots to 'see and avoid' each other as specified at Section 3, Chapter 1, paragraph 2. 3.2 Instructions issued to VFR flights in Class D airspace are mandatory. These may comprise routeing instructions, visual holding instructions, level restrictions, and information on collision hazards, in order to establish a safe, orderly and expeditious flow of traffic and to provide for the effective management of overall ATC workload. 3.3 Routeing instructions may be issued which will reduce or eliminate points of conflict with other flights, such as final approach tracks and circuit areas, with a consequent reduction in the workload associated with passing extensive traffic information.VRPs may be established to assist in the definition of frequently utilised routes and the avoidance of instrument approach and departure tracks. Where controllers require VFR aircraft to hold at a specific point pending further clearance, this is to be explicitly stated to the pilot. 3.4 When issuing instructions to VFR flights, controllers should be aware of the over-riding requirements for the pilot to remain in VMC, to avoid obstacles and to remain within the privileges of his licence. This may result in the pilot requesting an alternative clearance, particularly in marginal weather conditions. 3.5 Approach radar controllers in particular should exercise extreme caution in vectoring VFR flights – a geographical routeing instruction is preferable. Prior to vectoring, the controller must establish with the pilot the need to report if headings issued are not acceptable due to the requirements to remain in VMC, avoid obstacles, and comply with the low flying rules. Controllers should be aware that pilots of some VFR flights may not be sufficiently experienced to comply accurately with vectors, or to recover to visual navigation after vectoring.
There is a fine line between overcontrolling and neglecting your Duty of Care. Always cover your six!
I think someone already mentioned that the class of airspace is determined by the type and the amount of traffic in the area, not "what's routinely done". As for what's routinely done that can be covered in general in the beginning of the 7110.65 (in the US airspace system anyway).
The primary purpose of the ATC system is to prevent a collision between aircraft operating in the system...
I know that's a very general instruction and it's starting to sound like this has happened several times to you. Perhaps you can call the tower and ask what you can do to help alleviate the potential conflicts while transiting their "D".
Civil courts don't seem to care official accident reports and lawyers only care about the parts that help get them more money. Once the lawyers get involved everyone gets sued from the FAA to the flight school who trained the pilots. Often the controller is only person directly involved left alive making their testimony very desirable. If the accident involves a small regional jet with 50 people there's potentially hundreds of different court cases.
There's a case where two VFR planes on sight seeing flights crashed into each other (I believe everyone died). The family of one of the people on board sued a 3rd plane having a gear problem, and won, for talking too much on frequency. While it doesn't directly relate to what we are talking about. I bring it up to point out the technical rules of aviation like "see and avoid" or "no separation to vfr's in class D" have little bearing in a civil court proceeding.
Last edited by sykocus; 27th Jun 2012 at 09:40.