An intense afternoon of circuits!

[HeadInTheClouds]

So today I finally got onto the long awaited circuits. It was a bit windy today, between 15-18 knots but fortunately it was more or less straight down the runway. Didn't start out too bad, taxied out to the runway and I did a relatively passable takeoff considering I hadn't flown in a while.

 

After the first circuit was when it got interesting, I couldn't mentally cope with how much had to be done as well, between the checks, radio calls and looking out for other aircraft, my instructor ended up doing all the radio today.

 

On the first circuit we followed a warrior right in with not much dramas. On the second though we had to extend upwind for a while and look for an aircraft which had been told to go around behind us, turned crosswind to find 2! RPT's lined up on the runway, with the Dash 8 first and a 737 right behind it. While we were on downwind both of them took off. We also had 2 warriors in the pattern ahead of us, and so all the time we were trying to spot them until they finally popped out of all the haze hanging over the ocean.

 

Circuit 3 was much the same, this time we had to extend downwind until we could see the aformentioned 2 warriors through the haze, on final there was one of them just in the flare, another just coming down towards the threshold and then us behind them, and another warrior behind us. Came in for what I considered to be a good landing as it was one of my first with zero assistance, and the tower had to send the warrior behind us around because we weren't off the runway in time.

 

Anyway a busy day indeed, hopefully this will be improved on next time. Think I might go for an early morning session next!

 

 

[turboplanner]

Sounds good, there's always too much to take in at that stage. Don't be too put off by the other traffic, the lessons learned there will be valuable when you fly in to any busy airport, Natfly etc.

 

 

[HeadInTheClouds]

Supposedly visibility was >10km, but with seeing those aircraft literally just pop out of the haze I think depending on which way you looked it was closer to 1km!

 

 

[facthunter]

The figures are laid down for VFR. Do we comply or what? Nev

 

 

[HeadInTheClouds]

In this case the ATIS stated that the visibility was >10km, right for VFR. Looking from a higher level to a lower one into haze above the ocean seemed to shorten that a bit... but then again aircraft are usually hard to see on a good day.

 

 

[turboplanner]

Jake, welcome to circuits where what you experienced is what we all experienced. Unless you have the eyesight of Chuck Yeager who could see aircraft 50 miles away, what you are describing in normal. As a passenger, you didn't have to concentrate on seeing those aircraft. Your instructor will teach you scanning techniques. At Moorabbin, the traffic is so heavy I always brief the front passenger to point wherever he/she sees another aircraft in case I've missed it. It's easier to nod confirmation that you have it in sight than to miss it.

 

 

[Tex]

Sounds like fun and pretty normal for a training aerodrome, it is far more civilised flying into the YBBN than YBAF, those Class D ATC guys (and gals) earn their money. "Traffic is a 747 10nm on final" as compared to "Cleared visual 22L, remain left 10L not above 800', dual runway operations on 10, traffic is a 172 joining downwind 10L, Yak turning base 10L and an arrow on final 10 with a 44 approaching from the south for the central helipad"

 

 

[facthunter]

Tub,s it's called crew resources management. ( use everything that you have going for you). . Nev

 

 

[Guest davidh10]

Sounds like a good day and lots learned.

 

Just because visibility is >10km does not mean you can see an aircraft at that distance. It depends on a lot of things including the background behind the aircraft, its colour and its presentation. If it is straight at you then there is much less to see than if it is banking. That is why it is preferred to make a radio call before banking. It gives everyone a better chance of seeing you.

 

 

[turboplanner]

Radio is one of your key prompts, particularly with traffic ahead of you. When you hear the turn call done as David says look ahead to the approximate turn point and you will see the top of the wings much more easily during the aircraft bank. Of course you have to be alert for the few who either don't care and give the call well before or well after the turn, or follow this crap of see and be seen and don't use their radio.

 

 

[Guest davidh10]

You have touched on a very important subject, Headintheclouds. There are significant limitations to the "See and avoid" strategy. I've been reading a series of safety articles published by DDAAFS and one is on this subject. While the closing rates in their example is far above what we can expect with light aircraft, they aren't as big either. Consider the example of a military jet and a GA aircraft closing head on with individual speeds of 150 knots and 450knots. 20 seconds before impact they are about 6,000m apart but the visual object presented will only represent a 16th of a degree across. 10 seconds to impact, the size presented has increased to an eighth of a degree. At 5 seconds it is still only a quarter of a degree. See the representations of relative size in the illustration below.

 

 

Add to this the fact that the visual acuity of the human eye varies very significantly across the field of vision. It is only the Fovea, in the centre of the field of vision that has high visual acuity and even that drops off as the angle of vision moves away from straight ahead. See the graph of relative acuity below.

 

 

What this illustrates is that in the example, the aircraft that has to be seen and avoided grows from a barely detectable stationary spec to something that literally fills the windscreen in 3 seconds. Is that a bug on the windscreen or an approaching aircraft?

 

Allow for the fact that the pilot has to detect, then recognise the situation and then act. Each of these phases takes seconds. Another article I have been reading estimates the time from first detection to the aircraft responding to pilot avoidance action is about 10 seconds at best.

 

So this means that you have to be looking virtually straight at an approaching aircraft to see it at maximum distance. Complicated of course by the "blind spot" we all have in our eyes caused by the area where the optic nerve enters the retina. The brain fills in an image in that area, so we are not normally aware of it, however the brain puts in an image it thinks fits, not necessarily what is actually there.

 

Additionally, the human eye when looking at a "blank field" will not have anything to focus on and the muscles relax, resulting in a resting focus, which averages about a metre ahead of you. Individuals do vary, but if your eyes are focussed at short range, you aren't going to see aircraft in the distance, as they will be out of focus.

 

It was research findings, upon which this and other similar articles have been based, that led to the "Alerted see and avoid" principle being implemented. That only helps within the vicinity of aerodromes though. When you are out on navs between aerodromes, there's unlikely to be any radio alert to focus your attention.

 

This is why scanning and scanning technique is so important.

 

On top of all this, the eye / brain will detect something moving much more easily than something that is stationary. The real problem there is that an aircraft on a collision course will appear stationary in your field of vision, making it harder to detect.

 

It is well worth doing some of your own research and reading in addition to whatever your instructor provides. You can't know too much.

 

If reading this doesn't motivate you to keep your head out of the cockpit as much as possible, I don't know what will!

 

 

[HeadInTheClouds]

That was an interesting read, thanks!

 

 

[Tomo]

Sounds like fun and pretty normal for a training aerodrome, it is far more civilised flying into the YBBN than YBAF, those Class D ATC guys (and gals) earn their money. "Traffic is a 747 10nm on final" as compared to "Cleared visual 22L, remain left 10L not above 800', dual runway operations on 10, traffic is a 172 joining downwind 10L, Yak turning base 10L and an arrow on final 10 with a 44 approaching from the south for the central helipad"

Yeah, can get like that at times indeed. I tell you what though, once you get the hang of it, and understand and get the picture of what they are telling you, it makes for pretty easy flying.

 

 

[dazza 38]

Yeah, can get like that at times indeed. I tell you what though, once you get the hang of it, and understand and get the picture of what they are telling you, it makes for pretty easy flying.

I agree, at Boonah on a weekend.You can have 4 or 5 in the circuit.Some of them Gliders. You will get used to it.The key is the radio as well as a good look out.You have to get a mental picture of where everybody is.It comes with experience.Aircraft are alot easier to spot in a turn than straight and level as well.

Having said that flying at Archerfield was easier, because the ATC called the shots.If that make sense.

 

 

[Tex]

understand and get the picture of what they are telling you, it makes for pretty easy flying.

That's it Tomo, 'picture' is the operative word. Just like we fly the picture... good to have a traffic picture (in our mind). Traffic is relative, surprising how in tune your situational awareness becomes in a gaggle of gliders... though I tend to just run away if there are more than 10 in the same thermal, especially if it is light

 

[HeadInTheClouds]

An update here, had a brilliant morning of circuits this morning

 

Booked a lesson nice and early and woke up to find out there was no wind at all, the ATIS simply said "Light variable" winds, less than 5 knots the whole time. Did about 6 circuits in total, I managed to do most of the radio today as well. My takeoffs are pretty good now if I might say so myself, the art of balancing on the main wheels is getting easier. Landings are slightly different, managing to do them unassisted but there was one today that was *ahem* firm... But at least so far I haven't managed to bounce on landing.

 

We also started some emergency procedures today too which was interesting. My instructor demonstrated an engine failure after takeoff then I did a couple, not too hard really if you just remember to get that nose down right away. We also did a simulated engine failure on downwind and a glide approach, I found this pretty interesting, didn't have to add power at any point so I guess it was successful.

 

Traffic was also much quieter today and quite a bit easier to spot.

 

Anyway apparently I should be solo by Christmas, got a bit under 8 hours up in total now, getting closer to that magical 12!

 

 

[Guest davidh10]

Good on you Jake.

 

Bounced once myself on Tuesday doing a stream landing and hit a patch of dead air about one foot above touch down. It happens on the odd occasion. Don't worry about it, just move on. :-)

 

 

[Tex]

I make sure I bounce one every time I fly just to keep in practice.

 

 

[Neil_S]

Hi David,

 

Very interesting - thanks for supplying that info. Gives us all something to think about, and when illustrated in that manner it is very sobering just how little time there is to react.

 

Cheers

 

Neil

 

 

[facthunter]

If the other aircraft is stationary in the windscreen, you will hit it. If it is moving in a certain direction in the frame of the windscreen, move the opposite way. Having said this, it is a good idea to keep the other aircraft in view also, if it is not travelling in a constant direction, where you know? that it is moving out of your way, as time progresses.

 

Jet aircraft in a head-on situation have a closing velocity of about 16 miles a minute ( at cruise speeds) though you aren't in that situation, you could realisticly have a closing speed of 6 miles a minute near an aerodrome where feeder Airline ops are going in and out of certain aerodromes, so you have to get the avoidance technique correct if it is to work.. You should avoid the areas where this traffic is likely to be especially if there is an overcast out of which air traffic may appear on descent, without warning. Nev

 

 

[Guest davidh10]

.. You should avoid the areas where this traffic is likely to be especially if there is an overcast out of which air traffic may appear on descent, without warning. Nev

Just another reason to monitor CENTRE as well as CTAF. Better situational awareness. You often discover the existence, location and intentions of IFR aircraft by doing so, before they make any CTAF call, and of course if they are not "in the local area" then there is no CTAF call.

 

 

[HeadInTheClouds]

I remember hearing on centre in a past lesson, a call (callsign i missed) give their position as right near where we were, like really close, caused me to become very alert only then to hear "At FL410"...

 

 

[Guest cficare]

its interesting about eyes...

 

if u look at an object....its likely u wont see it....

 

there are 'blindspots and u need to scan..

 

..look here and look there!

 

 

[ayavner]

Doing circuits this weekend, I happened to spot an aircraft next to me, not by seeing it directly, but I happened to notice its shadow on the ground. Goes to show you have to be able to take info in from ALL sources, not just what you are expecting. No close call or anything, but made me go 'hmm'