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The "Mk 1 Eyeball" / lookout / see and avoid are almost totally useless

Anyway, I guess this is quickly becoming a pointless discussion...( I mean, what can you do about it?)....but I think probabilistically there is something more dangerous in those situations in the UK or Australia due to the fact that we are conditioned to swerve left...

YPJT, United Arab Emirates

Apart from being the rules of the air as well...> Copied from the shipping rules, so the reason is probably lost in history.

Maoraigh
EGPE, United Kingdom

Many pilots leave the landing lights on when in the pattern. With LED lights more available, many pilots are leaving their landing lights on for the entire flight. Just as strobes are ineffective during the bright of the day, so are landing lights. During WWII, before radar availability was widespread in aircraft and on ships, a program was undertaken to see if a B24 could be made invisible to the German U boats. The planned technique was to install lights along the leading edge of the wing. This had the effect of drastically reducing the contrast of the B24 against the bright sky and made it very difficult to spot from on the surface of the ocean. This was one of the first stealth programs and it is said to have worked in testing. It was never deployed as radar made it obsolete. So if you wish to reduce your observeability, keep your landing light on during the day. However, if you flash the landing light, the rods are extremely sensitive to changes in contrast and will alert an observer in an oncoming aircraft. A good example can be seen on some aircraft that pulse the landing lights mounted on the wingtips, they are relatively easy to spot.

In spite of the evidence to the contrary, here in the US, we are required to keep the anti-collision lights on at all times and most flight instructors train to keep the landing lights on in the pattern. When I operated a flight school, landing light maintenance added $2 to $3 to the rental rate. The bulbs would last at most 25 hours and it took a half hour of labor plus the parts to replace them.

When I get advised of traffic by ATC, if it is a general aviation aircraft, I don't bother to look for it until it is within 2 NM as I can't recall being able to spot traffic further away than that. An airliner may often be spotted 5 miles away, particularly if it is a jumbo.

I find that spotting aircraft at my altitude or higher is generally easier during the bright of the day than aircraft that are lower and have a darker background.

KUZA, United States

I have raised the issue of lookout training in a gliding context.

By the way, for what it’s worth, most gliding collisions take place in or near the circuit. I suspect that the same is true of power/power collisions. Glider/unrelated power collisions are so few as to have no statistical significance, but of the five that have occurred since 1970, two were in the glider circuit area, and a third was close to it. Airprox reports between gliders and unrelated power also have a significant proportion within the glider circuit area.

If you want technology to help detect otherwise unseen gliders in the UK (and probably elsewhere), only Flarm is going to detect a significant proportion. For reasons I have displayed elsewhere and don’t propose to repeat, most gliders in the UK do not have, and are unlikely in future to have, transponders. Personally, I fly with both Flarm and PCAS.

This is what I wrote to my gliding colleagues, as a result of which a study into lookout technique is being set up.

Look Out Training

I think we are doing it wrong. I do not claim to know what the answer is, but I think it should be revisited.

I don’t know anybody who actually conducts lookout in the recommended way, except when teaching to the approved patter. Nor do I wish to share the sky with anybody would fly that way. Instead, I think we all move our heads around the available visual arc, and up and down as far as we can, in a much shorter cycle. [clarification – this includes stopping eye movement to get a fix, as pointed out by another GA poster.] This enables us to pick up threats of gliders fairly close which present a large visual target, at the expense of searching for and identifying as a threat any and every far distant dot which may be a closing aircraft.

The Air Accident Investigation Branch (AAIB) referred to the scan problems in its report on the Cirrus/Grob Tutor collision (2 fatalities in the Grob) in 2009.

‘1.18.11 See-and-avoid

Various studies have highlighted the limitations of the see-and-avoid method of preventing mid-air collisions. .

The report is available to download from:

http://www.aaib.gov.uk/publications/formalreports/52010gbyxrandg_ckht.cfm :

Just how good is the standard lookout technique?

To quote from the AAIB report again (the BGA training is similar.) . . .

‘Lookout to the front and scan above and below the horizon, then attitude and instruments…. Move the eyes around the horizon in a series of steps (normally to the right initially), scanning up then down at each point…..continue the scan back to the tailplane and then look above and behind over the top and back to the front.’

The AAIB report continued to observe, and quote references to the effect, that a traffic scan takes time – at least one second at each fixation, so from 54 seconds to as much as fifteen minutes! A study they referred to included these cumulative time periods, in seconds, to react to an observed collision threat:

See object 0.1 Recognise aircraft 1.1 Recognise collision 6.1 Decide on action 10.1 Muscle reaction 10.5 Aircraft lag time 12.1 secs

Is even 54 seconds per complete scan good enough to detect in time a closing threat from, say, your 8 o’clock (only one such glance per 54 seconds, at best)?

Chris N

Ridgewell, Essex

It's worth mentioning that the RAF's response to the AAIB findings on the Grob mid-air was to spend a sizeable five figure sum on every one they had (100+ of them, IIRC) - they installed the Avidyne TCAS system like I have...

One might think that traditionalists would have instead overhauled the training to make sure people look out "properly" (whatever that means).

They must have concluded TCAS is the best approach.

It was not a cheap installation because it also involved putting in a Sandel SN3500 EHSI which alone is of the order of £10k. This was probably the most cost effective way to display the traffic.

Or maybe they spent the money as a due diligence exercise against future litigation?

Administrator
Shoreham EGKA, United Kingdom

I am advised that the MOD has purchased a number of Flarm units, so it looks like they are doing some trials.

Chris N

Ridgewell, Essex

Is there any way to integrate FLARM and TCAS, in the same display?

If it can be done, it would neatly cover both Mode C/S and the portion of the gliding community that uses FLARM.

Obviously "anything" is possible technically but I am not sure if any suitable display devices have more than one "traffic" input. For example the Sandel EHSI has just the one ARINC429 input for TCAS data. The old KMD550 that I have uses a KAC504 ARINC429 interface card which has multiple inputs, but I have no idea if it can merge multiple traffic data streams - be they ARINC429 or RS232. I never managed to get any data on the KAC504 and even the KMD550 IM and MM do not have anything other than a block diagram. So I guess one would need to develop and certify a "concentrator" box.

Administrator
Shoreham EGKA, United Kingdom

I would think it is possible, but I don’t know of it having been done.

PowerFlarm integrates Flarm, PCAS and ADSB in one display, I believe.

Some Flarm units have an outfeed to go into a separate display, so if that could take TCAS too, job done.

No gliders have TCAS, AFAIK, nor can I see any likelihood of that in future, so don’t look to gliding for a solution.

I do think that one day, ADSB might superseded Flarm, provided that the collision warning algorithms can be merged with ADSB. (Few people I know who have used Flarm would want to revert to “only” a PCAS-type alert system.)

By the way, we do know that Flarm (and the other things) are not a panacea – they are aids to lookout, not a means of eliminating the need. TCAS might be, in CAS, but not I think in the 3-D hotchpotch of flight paths in class G, and no way would it replace lookout in glider gaggles, for instance (nor does Flarm).

Chris N

Ridgewell, Essex

The "Mk 1 Eyeball" is PROB99 an old Royal Air Force expression, for keeping a lookout.

Often, I see a target on the TCAS at about 1 mile, my level (which means plus or minus 200ft, assuming his transponder is in spec; I know mine is spot on), and in the front i.e. 10 o'clock to 2 o'clock.

In most cases, no matter how hard I look and no matter how hard my passengers look, we never see him.

Even as he passed to one side of us, and probably very close (a few hundred metres) nothing is spotted.

Fortunately, as they say, the sky is big.

Administrator
Shoreham EGKA, United Kingdom

Well it was useful to see your TCAS display at least! The closest (I think) I've come to disaster is a near head-on over Swanley heading southwest towards Biggin. It really was last minute stuff but we both saw each other in time and turned the right way to avoid a collision. It's slightly reassuring to think that if one of us had been asleep we still wouldn't have collided. What are the chances two pilots would be asleep at the same time and place in the big sky?

1 mile you would think would be easy to see, but 200 ft above or below at 1 mile could be easily missed with all the blind spots on the typical GA airframe. Judging height with distance against a far away background can be tough as well.

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