Risk of Mid-Air Collision At Navigational Beacons

[Magp1e]

not good advice Englishal! If everyone operating in busy airspace asks for RIS as a matter of course, the frequency will get very busy. Secondly, you will detract the attention of the controller from other users that really require a RIS. If FIS will sufice, use it and leave RIS to those that need it.

[englishal]

It is not advice, it is what I do....

I am happy not to bother the SAME controller for a FIS if the weather is crystal, but if I feel the need for a service, then a RIS is what I ask for. If I am flying near a military aerodrome who offer LARS and I don't want to be run down by a Eurofighter I'd ask for a RIS. Otherwise I wouldn't ask for anything.

[bookworm]

Normally a FIS should suffice if the wx is good VMC and you are happy with your routeing. If the wx is not so good and/or you're not comfortable navigating through "tight" airspace close to CAS, ask for a RIS.

There's a commonly held misconception that collision risk is higher in poor wx. Collision risk depends upon two factors: the density of aircraft you might collide with, and the probability you might not see them before it's two late. Most pilots overestimate the effectiveness of sighting an aircraft on a collision course in good VMC. The traffic density factor is probably the more significant, in that in good VMC the traffic density at lower levels tends to be much higher.

Asking for RIS in good wx conditions in high traffic density areas when every man and his dog is up flying could lead to non-stop traffic information blocking thr freq!

But ironically, this is exactly the time when you need the most collision aavoidance help from ATC.

Under RIS you should get a warning if you are approaching CAS, ATZ's etc.

No, you shouldn't. If you have been identified and issued a discrete squawk, whether under a FIS, RIS, or RAS, there is a higher likelihood that ATC will offer navigational help of that sort. But navigation is the pilot's responsibility.

[Cusco]

Our Arrer has a natty facility on its very ancient RNAV (NS800) called VOR PAR(allel) which allows us to fly a course to a VOR, but offset by 1 -5 NM to fly a parallel course to the VOR:

I don't see why this facility shouldn't be available in GPS units: it would certainly dilute the 'honey-pot' effect, until of course everybody had one and everyone was flying offset by 5 NM......

Safe flying

Cusco

[bookworm]

I don't see why this facility shouldn't be available in GPS units: it would certainly dilute the 'honey-pot' effect, until of course everybody had one and everyone was flying offset by 5 NM......

But the offset principle is that everyone offsets from the centreline to the right. So while you may encounter another aircraft going in the same direction as you, you shouldn't encounter one in the opposite direction.

The offset facility is available in GPS units at least to the extent that it is in your NS800. With both, you can allow the CDI to indicate 1 mile right of the "desired" track and keep it there.

[Fuji Abound]

I think it is worth repeating some information from an American study.

It takes 13 seconds from seeing an aircraft and realising it is going to hit you before your aircraft reacts to your command to avoid the collision.

At typical fast GA speeds at 3 miles head on you have less than 20 seconds to spot the aircraft, and at slower speeds maybe up to 40 seconds.

A good 180 scan takes between 20 and 30 seconds - try it out on your watch.

Next time you are receiving a RIS listen out for the range of the aircraft - see what you can spot when you are told where to look. I do the same with RIS and TCAS - it is really interesting the distances on most days at which you see the traffic WHEN you know where to look.

In short, dont kid yourself, see and avoid really doesnt work at all well - I think it may be one of the significant myths of light avaition.

The real reason there are so few collisions is due to the big sky or electronically aided avoidance.

[Magp1e]

Bookworm

I think you missed the point of my post. I implied that if you ask for RIS as a matter of course, even when FIS would suffice, then you would increase the controller's workload therefore degrading the service provided to fellow pilots who really needed the extra services RIS provides. If you find yourself inside the melee then of course, ask for RIS; but if you're in a quieter piece of airspace listening in to a "free for all" over BNN then ask yourself if FIS would do.

Point 2, RIS is not an collision avoidance service...it is a traffic information service...the pilot is responsible for collision avoidance.

Point 3, Yes! you should get a warning if you are approaching CAS/ATZ's, unless you have informed the controller that you have clearance to enter. The reason being that a controller cannot provide a service in CAS/ATZ unless he has had permission to enter it. This will not always happen under FIS as there is no requirment to identify an ac under FIS as it is formally a non-radar service.

[Pitts2112]

Cut it short

A tip my instructor gave me when I was doing my PPL training:

Beacons of any kind are airoplane magnets. Don't overfly them. Cut the corner short by a couple of miles. I never overfly beacons because of that little tip.

Pitts2112

[ShyTorque]

Very good tip; I do this whenever possible; especially BNN and DTY.

I fly a TAS equipped 150 kt IFR helicopter; if necessary I get by in Class G without adding to the ATC workload (and level of RT chatter, which affects everyone) by listening out and building up a mental picture of the traffic situation around me and avoiding controlled airspace, rather than requesting a clearance through or a FIS/RIS. I often elect do this if someone ahead of me in the RT queue has been told to "Stand by" by ATC (he's busy).

Having said that, in such instances, if I think my presence might affect someone else, then I speak up to ATC at first opportunity, even if I'm not required to.

TAS / TCAS is a huge help but ONLY if pilots of aircraft fitted with a transponder use it for the purpose intended whenever possible. It should be remembered that a mid-air collision affects two aircraft, so it's in the interests of all to use transponders, where fitted, to everyone's best advantage. By doing so, pilots of TAS equipped aircraft operating in Class G have an even better chance of seeing and avoiding.

I always bang on about this but if your transponder has Mode C, then PLEASE use it, rather than just Mode A. A relative height readout allows me to gain vertical separation from my TAS readout. If your transponder only has Mode A, then just use that, but please do use it all the time, not just when ATC request it.

The "big sky" principle is OK to some lesser extent, but around a choke point such as a beacon, it suddenly isn't so big! I know one pilot who has survived TWO mid-air collisions in helicopters - I work on the principle that I'm not that lucky, not even half as lucky.

[S-Works]

150kts, what you flying Airwolf or Blue thunder......

Or i it like permit builders where there aircraft all done 140kts on 3lph of Mogas....

[bookworm]

I think you missed the point of my post. I implied that if you ask for RIS as a matter of course, even when FIS would suffice, then you would increase the controller's workload therefore degrading the service provided to fellow pilots who really needed the extra services RIS provides. If you find yourself inside the melee then of course, ask for RIS; but if you're in a quieter piece of airspace listening in to a "free for all" over BNN then ask yourself if FIS would do.

I think there's some merit to your suggestion, but a particular pilot is often in a poor position to assess the traffic density in the airspace around, and therefore if the RIS is "really needed". IMO a FIS is never "sufficient" if a RIS is available, as it fails to take reasonable measures to mitigate risk as far as practicable.

Point 2, RIS is not an collision avoidance service...it is a traffic information service...the pilot is responsible for collision avoidance.

The primary objective of (practically) all air traffic services is to assist with collision avoidance. The manner of that assistance differs according to the level of service, but traffic information is obviously provided to assist with collision avoidance, not as a running commentary to airborne aircraft spotters!

...This will not always happen under FIS as there is no requirment to identify an ac under FIS as it is formally a non-radar service.

We'll see how this works out after the new ATSOCAS stuff is introduced. I stand by my point that, with the exception of an aircraft receiving vectors under a RAS, it is unwise to rely on navigational warnings from ATC.

[Magp1e]

it is unwise to rely on navigational warnings from ATC.

That is probably very true from the pilot perspective. BUT believe me, if a LARS controller is giving you a (radar) service as you approach a CTR/ATZ and doesn't warn you, then he's not doing his job!

[Fuji Abound]

I fly a TAS equipped 150 kt IFR helicopter; if necessary I get by in Class G without adding to the ATC workload (and level of RT chatter, which affects everyone) by listening out and building up a mental picture of the traffic situation around me and avoiding controlled airspace, rather than requesting a clearance through or a FIS/RIS. I often elect do this if someone ahead of me in the RT queue has been told to "Stand by" by ATC (he's busy).

The problem is that if everyone adopted the same approach no one would be receiving a service and you would not be able to form a mental picture of where the traffic was.

Mental pictures also rely on accurate reporting.

En route to France today another aircraft called up the field to say he was south abeam and reported his level as I departed. He could well have not bothered but because he did I knew roughly where he was and when I would over take him. Trouble was he reported his level at 2.5 and about 5 minutes later he was apparently at 800 feet, although when I spotted him on TCAS he was at 3 as I climbed through his level. That re-enforced that you should never assume the levels or positions are reported accurately. Both I and the ATCO were slightly bemused!

I also always worry when aircraft are requested to report a range from somewhere. Do you bleieve them? Often the circumstances help determine. For example the same aircraft was asked by London Info to report his range from the beacon - 10 miles he said. It was clear form his track that he was probably not using the beacon and even if he had been, he was past it. He piped up very quickly with ten miles. I suppose you should always be suspicious when a distance is given so quickly in circumstances it was unlikely to be dialed into the DME, and it was a round number. A joy of the G1000 is you can toggle to anything on the map and it will give you an instant range and bearing. It takes a few seconds. I was also asked my range which was 8.4 miles, and yet I had passed him about 10 minutes earlier and I guess I was going 70 knots faster. The quickness of his repsonse and the earlier "confusion" over his height already had me wondering. Later the same traffic claimed he was VFR, and yet I had gone through the same airspace maybe 15 minutes earlier and he could not have been VFR at his height. I think it is vital pilots are accurate and honest in their reporting. If I think there will be any chance of a conflict I will adjust my level to avoid and tell the serivce I am working that I have, however if the other pilot is inaccurate with his position reports or more importantly his height, it all become pretty pointless.

I can think of many occasions I have heard I am south abeam of x and you spot the traffic quite clearly north abeam.

[ShyTorque]

The problem is that if everyone adopted the same approach no one would be receiving a service and you would not be able to form a mental picture of where the traffic was.

Obviously - but I'm paid to make captaincy and airmanship decisions and I adapt to the circumstances. If the frequency is quiet then I'll get an ATC service myself. If it's obviously very busy then I'm better equipped than some pilots are to make do without making RT contact with ATC.

Bose-x, It'll go a bit faster still if needed. and I'll bet the owner wishes it was only 3 lph; unfortunately it's more like 3 gpm!

[Fuji Abound]

captaincy and airmanship decisions

So what is the difference between the two?

[ShyTorque]

Depends whether you are single or multi crew.

Do you have an issue here, Fuji Abound? You seem to wish to find criticisms away from the main topic.

[Fuji Abound]

Do you have an issue here, Fuji Abound? You seem to wish to find criticisms away from the main topic.

Who me .. .. ..

I was just commenting on your comment in repsonse to my comment about the topic .

.. .. .. and so the two are different depending which you are then?