Scanning
 

liam,scanning for other aircraft is covered in Air Pilot Manual 6-Human factors and pilot performance.
This is of utmost importance,I would ask your instructor to demonstrate the method,as has already been suggested.
It was drilled into me that looking all around really well, before a turn, is paramount.
Especially the area you are turning into.
And of course the circuit.
Lister:)

Unfortunately, that's not the case. You're doing 150 kt. An aircraft reported in your 12 o'clock, "opposite direction", at 5 miles may be passing safely down your right side by a mile. A right turn of 30 degrees puts you perfectly on to a collision course with him if he's doing the same speed as you. More than 30 degrees then? What if he's just a little faster than you? :(

If the controller simply said "turn left to increase separation" or even described the encounter as "left-to-right" which, in terms of relative bearing, it is, the action to take is obvious -- you turn to the left.

Not down here for me in the South/South East. It's because the airspace squeezes us into a tight band of low altitude class G.

TrafficPilot

The very purpose of paint is to absorb light. It reflects the desired colors and absorbs all the other visible light.

You would need a "paint" that converts light into something else. Photovoltaic cells are the only device I know to exist.

Maybe some new nanotechnology based on quantum dots will be able to change light frequency and have paints that appear to be unnaturally brighter (and cool).

Bye,

If there was opposite direction traffic, same height, I'd be thinking of turning more than just 30 degrees. With a combined closing speed of 300kts you have 60 seconds or less to take avoiding action. I think I'd take the hint from the controller who's trying to help, rather than elect to plough straight on and play the odds of just how recipricol the "traffic, opposite heading" call was. You're right that it would be better if the controller could drop a hint, e.g. "suggest turn right for avoiding action" but I'm not sure if they're mandated to do that or not.

[later edited because I'd missed the bl**dy obvious]....should have added that climbing or descending, depending upon airspace constraints, would also be an option.

In the days before radio they HAD to lookout and were much more disciplined about (for example) circuit joining procedures. Ok there is a larger diversity of traffic around now but in many ways not a lot has changed if you are operating VFR.

Whilst not being a luddite I think the overuse of services such as Radar/FIS etc can lull pilots into a false sense of security. There are also more potential distractions such as the GPS, even changing frequency means head in the cockpit during which time another a/c can be filling the windscreen.

I know it's a generalisation (and I speak as one who has spent most of his flying career in civil aviation with a spell as a military flying instructor) but in the military there is much more emphasis on LOOKOUT since apart from anything else if you don't spot the enemy first he might shoot you down. So it's surprising to see that recent midairs have involved military operated a/c.

When teaching lookout on early details with students I tell them that lookout is an acquired skill and, at this stage, just because they cannot see an a/c doesn't mean there isn't one out there. Also don't get preoccupied with the one you can see - keep scanning!!

Finally, make sure the windscreen is clear - in summer a screen full of squashed flies can mask the target which might spoil your day!

I'm just getting into this aviation,and unlike any other discipline I've been involved in none of the 'Rules' ever seem to be appropriate to the situation and pilots seem to go out of their way to do the opposite.

UKANO collision avoidance in the air Rule 8,when approaching head on,each must turn to the right.

Given the scenario of direct head on confirmed by range closing,bearing not changing, why should anyone contemplate a left turn,as bookworm has suggested ? No, seriously, tell me, there is probably a good reason which my superficial approach has missed.!

In the last 6 months albeit flying in an uncongested part of the uk (not saying where as it would then become the most congested):\ I have never seen the 'strobe' of other 'craft.
This bit of equipment needs serious re-engineering to become effective. In other environments strobes are used for collision avoidance,drawing attention to alarm states etc. very effectively,but the aviation variety needs an order of magnitude upgrade to be useful. Perhaps if feasible this would be a cheap, simple, universally applicable and effective way of improving see and be seen.

atceng

Notwithstanding Rules of the Air rights of way - you are entitled to do anything to avoid immediate danger - just because you have seen him doesn't mean he has seen you!

Also emergency (ie avoidance) turns are not in the PPL syllabus whereas the military do teach them to students. I think ETs should be in the PPL syllabus - there was a thread on Pprune a while ago on this topic.

Because that was not the scenario. The key point is that "12 o'clock" is not the same as "direct head on". The bearing can change quite a bit and still be "12 o'clock".

That was most definitely not the scenario I described. If you could see the other aircraft, you'd see the bearing was steadily increasing. If you simply assume, based on the controller's "12 o'clock opposite direction" limited information, that the other aircraft is on a collision course, the right turn that you suggest would take you into conflict with the other aircraft.

The reason why a "Traffic Service" ATCO does not give avoidance vectors is because he is not allowed to. Rules are rules. Safety doesn't come into it.

Agreed!:ok:
It makes little sense, in my view, to require a good lookout to be kept at all times, while at the same time teaching navigation methods that appear to maximise the time spent on navigation! Whether it is toying with a GPS with ten million features, or trying to match every church, barn and tree with the map, it just takes too long and is not necessary. Navigation is about getting accurately from A to B, isn't it? So why aren't students taught how to navigate with the minimum possible effort to accomplish that task?

FLARM
 

I posted the following on the original thread about two aircraft down.

I think it is worthy as a contribution on this thread also.

A mid-air collision is a dreadful event which any pilot would want to avoid.

However, the solution for GA is not as simple as putting a gadget on the panel
to do the looking for us.

The FLARM is a good device for glider pilots in the environment they fly. But only any good if all the other aircraft likely to be met in the air are likewise equippped.

I have installed a FLARM system to a GA aircraft engaged in glider towing. When fitted to a powered aircraft it needs to be heard over the noise of the engine and radio. It will therefore need to be properly powered and connected to the aircraft's audio system. This will involve a modification to the aircraft which will need CAA approval (for a fee) and installation (for a fee).

To connect the FLARM to the audio you will also need a FLOICE unit, which is a voice-intercom interface.

Remember that a glider pilot usually has a bubble canopy with excellent vision capabilities so in the event that a FLARM warning is given (visible and audible) the pilot can quickly look for the conflict and take avoiding action. I believe the range of the FLARM is such that a warning is given 15-20 seconds before possible conflict.

Most GA aircraft do not have such good all-round vision and as such, a FLARM alert may not give the pilot time to digest the audible and visible information, look out to verify, given the many blind spots inherent in GA aircraft and take the correct avoiding action.

I am of the firm belief, as a PPL of many years, that the basis of collision avoidance in the FIR can only be a good scanning technique.

As is so often the case in these events, it is better to wait for the AAIB report before deciding a course of action based on where the perceived problem was in the case of the event in question.

Which reinforces my feeling that the Mk 1 eyeball doesn't cut it. You just need to fly in a TCAS equipped aircraft to realise how much "invisible" (but transponding) traffic there is out there on a clear day. Get in the haze under an inversion layer and you've got to hope that the big sky theory works! I'd rather have ADS-B.

bjornhall, and others advising arbitrary avoiding action (new acronym AAA) the opposite to the rules,you make my case perfectly.

If a consistent heading of 12 oclock even allowing 30deg isn't developing into a direct head on when the bearing doesn't change from 10 miles,5 miles,3 miles,1 mile,then I hope never to be flying in the same airspace.

Draw it out and see! Then work out what happens if a right turn is made and the other 'craft does nothing,'cos he hasn't seen you or turns right,'cos she has,(ignoring the possibility that its old bjornhall who's going to turn left).

Work out the permutations and you will see that you are certain to avoid by prompt rule-following action. If both 'craft follow the rules even better.
If one 'craft does the opposite to the rule then wham, another statistic.

Lets all just follow the rules,there isn't time to argue even with yourself.

atceng

atceng, the thing you are missing is that ATC traffic information is not accurate and precise enough to use for maneuvering. That requires vectoring. Traffic information is a great help since it tells you where to scan for traffic. Following the rules for collision avoidance comes after you have acquired the traffic. If you are drawing geometry in the cockpit you have your priorities all wrong.

But I also think you are concerning yourself with the wrong issue. Midairs do not happen because pilots fail to follow the rules regarding maneuvering to avoid collisions. Midairs happen because pilots fail to see each other. So rather than get distracted by this unimportant tangent, let's focus on the real issue: How to spot other traffic.

The RAF did some research a few years ago and came up with black being the best colour for air to air visibility, hence they now paint all of their training aircraft black except for the tips etc. My last aircraft was Fibreglass and white but it did have a couple of black areas ,wing walkways' however these got extremely hot and I would hate to have had the whole aircraft that colour. On a previous white aircraft I covered the leading edges of the wings with silver reflective tape and this was extremely good for visibility. (but I don't know if I should have put this in as a mod?)
In practice there are very few mid-airs however I have a policy of never planning a flight from overhead the field and flying at altitude just higher or just lower than the thousand feet mark. pilots often take a pride in being at the exact height - often a multiple of a thousand foot! so stay out of that zone.
In GA flying KEEP AWAY from glider sites and parachute sites.
My penneth.

when meeting another aircraft head on .......
 

Both should turn right, right? Well, that's the rule, isn't it?

Twice while tugging up a glider, this didn't work.

Junior Nationals Gliding Comp a few years back at Weston on the Green, pulling up a 19 with a Navy pilot, noticed a twin hauling a.... out of Kidlington, so I turned right to avoid him (of course towing a glider, I theoretically had right of way, right? )

He turned left.

I had nothing left to do but dive, with the Navy 19 still hanging on for dear life. Which is the right action for the glider on tow; we present one target (if a rather extended one) rather than two disparate targets. It was nice that he backed up my story when I returned to ask the director to please let Kidlington know what we were doing and where.

The other occasion a very experienced glider pilot was behind me and warned me of traffic; I hadn't seen it (nose high, you know) and began to turn right, and he said very very emphatically "TURN LEFT NOW!!!!" So I
did, and it was so near that if he hadn't directed that avoidance, I wouldn't have been here to file the airprox. The equipment on the glider exactly pinpointed the time and place, so we were able to trace the opposition.

That pilot had thought it would be sensible to dive under the combination.
Not really; if we hadn't seen him and diverged just then, it would have been
normal for the tug to descend.

I say again, LOOKOUT, LOOKOUT, LOOKOUT. Please.

Sunday was the best gliding day so far this year. In terms of weather. Obviously and very sadly not for those involved in the mid air near Abingdon. I would guess that a large proportion of the UK glider fleet (c. 2500) was airborne on Sunday and a fair proportion of them in the southern England area OCAS. See Daily Scores for those that logged their cross country flights - and that is by no means all who did cross countries on Sunday. And look at the distances flown - sans moteur.

I suspect there were a great number of GA aeroplanes also in the height band 1000 - 5000 ft AGL, below cloud base.

What this shows is that Sunday was the equivalent in road traffic terms of a sunny bank holiday weekend on the M5 to Devon - crowded. So statistically one would be more likely to encounter more than the odd aircraft en route.

Now even the proponents of using any ground based advisory radio or radar service in Class G will quickly realise that with (a) the speed at which the high volume of airborne traffic is moving (b) the delay factors contacting and getting a response from the ground based third party (c) the overload factors on a ground based person (d) the fact that gliders do not follow a straight line necessarily and are constantly ascending / descending, then it is impossible to have a fool proof ground based human third party intervention system to keep us all apart.

So the quickest means to do so is constant lookout. Backed up by Flarm or something similar. I have flown with Flarm for 4 years now - mostly in the French Alps - and I can say with confidence that it reduces risk but of course will never eliminate it. The price is worth the extra mitigation.

As to conspicuity, there have been various experiments conducted over the last few years with regard to making white gliders more visible. None have proved conclusive of a better scheme, other than the RAF black (which of course we can't paint our gelcoat gliders with, for reasons already given in this thread). Even orange dayglo strips and markings on the wings do not work that well. In fact my French colleagues - with many '000s of hours mountain flying - say that often these markings break up the profile of a glider against the mountain / snow background, with the result that the aircraft becomes a smaller profile. This I experienced first hand last month high in the Alps when the Flarm gave a 'three reds' alert. Neither my co-pilot nor I could see another glider until it passed close in front and underneath us as we thermalled. And the other glider was covered in dayglo strips. BTW my eye test last week was A1....I write as someone with 40 years' gliding, 2700 hours and some power flying. I intend to do a lot more as well, looking out and hoping I see everything. But I won't rely upon third party sources on the ground for this.

thats my last written exam left to do after aero tech. I am aware of clearing turns and looking before turning. I was under the impression reading this that there is a specific scan technique when flying straight and level.
At the minute I split the view into different parts and scan each section at a time, middle, fore and back. I will ask instructor though next lesson.

If the Glider had had £390 worth of PCAS he would have “seen” the Tutor (assuming it had a transponder. If the BGA encouraged the fitting of Flarm and PCAS and the rest of us fitted Flarm and PCAS we would all be £1000 less well off but much less likely to fly into each other. I am hoping to test a Flarm in my MCR very soon (will report back) and already have PCAS. Collision avoidance which combines detection of Flarm and Transponders is less than 12 months away.

Flarm has a range of 3 - 5km (according to the manual), my PCAS is set to 5nm.

Rod1

Fly high - that's the best option.

A parachute is no good if you have passengers, or if you got incapacitated.

IMHO, you will never spot the one that is going to hit you, for reasons already mentioned.

If we are talking about reducing collision risks with gliders, do not fly in the band from cloudbase to 1000 or so feet below it. That's where the cross country gliders will be

I think this whole topic should be broken down into parts:

Firstly, there are various things you can do to reduce the risk of collision that are unrelated to detecting the other aircraft. In short these "things" all revolve around avoiding areas with a high density of traffic - as IO540 says, fly high for example. I gave in my first post a list of other things that will help.

Secondly, developing a scan technique to give you the best chance of spotting another aircraft. However, kid yourself not, if you take the trouble to read all the research, our eyes are really not up to the job. You will get quite a different impression from this and other forum - all I can say is those who punt this are irresponsible and clearly havent read the research.

Thirdly, we can use technology to help. Technology inevitably is the last line of defence. The kids on the chopping block are PCAS, TAS, FLARM and transponders. FLARM is the odd one out because it is only gliders that really use FLARM and even then I personally suspect the uptake is no where near as large as they would have you believe. For that reason, transponders and PCAS or TAS IS the only game in town at the momement, if you have to select one or the other. The alternative is to have both.

I think it is worth recalling that the research you are talking about mainly relates to the cross country type of collisions. It is also worth recalling that proper scan can still significantly reduce the risk of such collisions, while it can not bring it all the way down to zero. A third thing worth remembering is that collisions in congested areas, such as the traffic pattern, will have more to do with improper lookout than with the physiological hard limits of the eye.

To draw the right conclusions from such research, one has to understand its scope...

Entire UK gliderfleet airborne on Sunday
 

David Roberts points out that more than 200 crosscountry flights were logged on the BGA ladder site this day.(Sunday, 14 May) That is only a small proportion of cross country flights actually made. From our club alone, every single seater that could stagger into the air actually got somewhere. One pilot flew 723 kilometers, launching at 10 am and not returning until 8 pm; as I was supervising that day, was about to phone his wife to ask if he had notified her he might be late for dinner, when he arrived over the hedge.

We try to keep track of our people: before leaving they must note their proposed turning points in a Cross Country Book. But trying to contact them by radio from the ground is not done; most likely they are on a different frequency, or switched off in order to concentrate on the flying.

LOOKOUT,---THEN Aviate, Navigate, Communicate.

Fuji, there is no central source of figures for gliders with Flarm, because they are getting them from different places at different times. My guess is well over 200, of say 2300 gliders, and growing along an S-shaped curve – slow to start, then a rapid acceleration until most have them, then slow for the last few. It is a bit like the first few people who got telephones – not much use until a lot more got them, except for the few in an immediate communication circle who talked to each other. As the largest gliding club in the country has several dozen based there, and have fitted them to all their club fleet, my guess is that the rest at that club will rapidly follow except for the last few.

Similarly, it will happen at other clubs, probably the largest at first, and those hosting competitions, and those hosting lots of visiting pilots for mountain wave expeditions etc..

The experience of last Sunday has, I believe, added a lot more potential buyers of Flarm in the gliding community. I see quite a few people talking about it now. Maybe, just maybe, some of the other GA people will take more interest in it too.

After trying PCAS (the Zaon MRX), I took delivery of mine today. That will help detect transponder–equipped, GA, particularly the low level ones who insist on flying over glider winch-launching sites (in breach of Rule 12) and those when I am soaring at lower levels before getting higher than most GA flies at. (On a flight to try Rod’s PCAS which I borrowed, all the contacts but two were lower than me. One of the two exceptions was probably a Stansted departure. The other was when I was on the ground, and a spamcan flew over our winch launch area at about 1000 feet.)

In the short/medium term, only lookout will help with non-transponder equipped GA unless/until they become sold on the idea of Flarm too. As Rod says, £1000 buys PCAS and Flarm, and gives IMHO a huge leap without needing EASA and other obstacles to be overcome. Not perfect, not 100 percent, but a big improvement.

By the way, I expect my experience on Sunday was similar to many glider pilots. During a 7-hour flight between East Anglia and the Welsh border, the first hour was at 1-3000 feet and I saw a few spamcans (mostly in the choke area of class G just outside the Stansted CTA), including at least one that I saw over our winch launch site (my friends on the ground saw several more during the day); the middle 5 hours was mostly at 3-5000 feet, and I saw lots of gliders at my height range, but all the power GA I saw was lower; and the last hour was much quieter. When I was working Cambridge Approach, all the power GA I heard about was well below me.

So the greatest power/glider risk was mainly in the early part, before I could get high. After that, and for 80-90 percent of my flight, it was mostly glider/glider risk.

I have lost hope of convincing the anti-glider and/or pro-transponder brigade that Flarm (now Flarm + PCAS) is the most cost-effective and as well as the only widely practicable technology to reduce collision risk, but that’s where I am at.

Chris N.

I commend anyone who can sit in a glider for 7 hours....

Or simply out of range. It's one thing to hear base from 150k away when at FL100, it's quite another at 3,000' AMSL.

BTW major congrats to whoever did the 700k, and of course to everyone else who did anything.

I should have added that I have borrowed Chris’s Flarm.

At the Weekend almost all the Gliders were up, a very large % of the Micros and the LAA fleet were also likely to be airborne. We all need to work on our lookout, but a practical traffic alerting solution is possible with current tec at a fraction of the cost of a transponder.

Rod1

Following on from the various 'collision threads' I have done some eyesight checking -- and am depressed.

At every opportunity when I have had another aircraft on collision course (normally following someone on a departure - so not a big threat), I find it very difficult to see that stationary dot more than about 1.5 NM away. Even at 1 NM, I need to 'know' where the target is to see it. On the other hand, if a target has relative motion, I can usually pick it out up to about 4-5 NM.

In every case traffic has been called to me, I can only see it after relative motion has started to be noticeable.

The conclusion, I can't see en-route traffic in time to do anything about a collision - If I can see it, I am going to miss it anyhow!

Obviously coming near the circuit is different as everyone is changing course all the time, so you have a good chance to spot most traffic and avoid turning into someone.

Did the pilot flying the 700km plus set a new record? Any more details, please?

The one from Dunstable that flew over 800k thinks he might have set one...

Good for him, any idea of his route?

If I was being approached head on by traffic at same height....I'd drop down 100'. That is the thing I like about flying with a ZAON XRX - the azimuth data is pretty good but so long as there is a vertical offset no collision.

One thing though, very rarely does a collision happen in S&L flight. Normally it is caused by one or both aircraft manoeuvring - makeing turns, climbing, descending.

Regarding FLARM - if it is interfaced to the Garmin x96 GPS's then you can have audio warnings as well as position displayed on the GPS screen. I interface the ZAON through the 496 and it displays the traffic on the GPS and tells me when there is dangerous traffic about as I also have the 496 wired into the intercom. If I could somhow get a FLARM box without built in GPS (cheaper), then inject the NEMA position into the FLARM box from the 496, then interfece the FLARM box back to the 496 to display the traffic on the screen then one could have a very neat FLARM installation which could be hidden behind the panel - possibly just having a hull mounted antenna installed (is that a Mod?)....Would be great if you could do the same with a ZAON type box and have a hull mounted antenna for that.

Dave Robert's post on the previous page mentions the Daily Scores website:

http://www.pprune.org/private-flying...ml#post4999839

As Mary said, loads and loads and loads of flights for Sunday, and many more that weren't put on the ladder, plus many more soaring instructionals. It's going a tad far to suggest that every glider in the UK flew as conditions further north were horrible, but well over 1,000 seens not unreasonable.

Someone at Lasham declared just over 1,000k, he didn't quite make it.

The north-most launches seem to be Rufforth, Pocklington & Sutton Bank, and they tasked to the south.

Cirrus Design developed special colour paints (took quite a lot of effort and time) to break out of the "Got To Be White" tradition.

Look at Photos: Cirrus SR-22 Aircraft Pictures | !!!!!!!!!!!!!!

Perhaps the RAF will in future be saying to any training aircraft supplier that "Got To Be White" doesn't hold true anymore and we're not buying any more of them...?

Maybe the glider manufacturers could approach Cirrus to see about how to get some of this paint, assuming suitable, onto gliders too.

The colour paint is relatively new technology. Personally from an 'avoiding mid-airs' I would like to see it used as widely and often as possible, considering how much 'got to be white' we are collectively capable of putting in the sky on a nice day.

Thoughts on Lookout
 

Several posters have noted the relaitive difficulty of spotting a static (ie real risk of collision exists) target as against one where there is relative movement across the canopy (and low/no risk of collision)

However gliders rarely fly in straight lines and very few GA aircraft are required to.

To avoid the dots staying static before your eyes, first, move your head: a moving-head scan (IMHO) picks up more than a long stare. Second, manoever the aircraft. Pre aeros/spins checks recognise the need for 'clearing turns' to get a good view in blind spots above/below/behind; well why not do some in normal flight? They don't have to be knife-edge manoevres to panic the pax, just avoid sustained stright-line flight - every change of heading (with its instinctive associated extra lookout) increases chances to acquiring a target.

Not rocket science, but every little helps

'Simples!'

BTW, I question the contributor who reckons greatest risk of collision is in the circuit: with everyone going the same direction, with the same intention and on the same frequency, all these factors reduce collision risk.

My top candidate for a collision black spot is a recognisable landmark, suitable for use as a glider or GA cross country turning point, especially if it also marks a choke point between areas of controlled airspace. The combination of the controlled areas squeezing non-IFR traffic into smaller spaces and the landmark attracting them multiplies the dots on the canopy amazingly!

It would be fine to have new aircraft painted with the Cirrus paints assuming they are suitable and Cirrus will release the technology. But, there are large numbers of 'legacy' aircraft which are white because they are composite, and buying Flarm and TCAS is far, far cheaper than getting a glider refinished or (I imagine) an aircraft painted...

Not arguing against FLARM. TCAS etc. Highlighting "Got To Be White" ain't necessarily so anymore.

If I were RAF AEF I would be interested in at least a costing for putting some of this paint on an existing GRP aircraft. And FLARM, and TCAS.