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Va and fantastic plastic

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IF it's going pear shaped, go around. without hesitation. Get your instructor to make you do a few as they can be quite critical if you bounce or such. You might have to fly in ground effect for safety, briefly rather than have wheels touch when sideways. I went round on my first solo.. (Don't tell anyone). Nev

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Hi Turbs

the exciting day. I have no idea when that will be . I can problably not break the plane in smooth angel air. I learned what a baloon was yesterday when it got a bit gusty.

It is interesting how confidence with particular manouvers ebs and flows . I thought my finals were getting pretty good yesterday until the wind came up.


One of thing things I realised. if a cascade of things are wrong, rather than geting over focussed, stop and reset, look around, reassess your current flying parameters.


An over-focus on one thing will get you ignoring something else to your hazard

The ebbs and flows are normal, just your system adapting to the fact that no two circuits are exactly the same; you're flying in an ever changing air system.

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The ebbs and flows are normal, just your system adapting to the fact that no two circuits are exactly the same; you're flying in an ever changing air system.


Not only that, you are in a medium you cant see, except with the aid of a device like a windsock, or ripples on a dam, etc and yet you must react appropriately to its every mood - challenging even for the most experienced.

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Va is intended to provide some margin between normal flight control operation and that which might place the airframe into a higher risk zone.

Va is calculated as: sq.rt of positive load factor x Vs

Vs is of course clean stall speed.

Vs depends on MTOW - lower MTOW = lower Vs

Va will often be given as a range in a POH.


My Brumby R610 is neither a speed machine nor a STOL.

Its aluminium, not glass/composite, and so isn't the same strength.

It is a utility aircraft with +3.8 and -1.9 load factors as given by factory

SqRt of 3.8 is approx. 2.0

Vs at MTOW is 44

Va is therefore approx. 88KIAS @ MTOW - but very much lower if flown solo with 2 hrs fuel.


In practice, you can work it out by taking an aircraft out, with your intended load of passengers, fuel and freight - then conduct a vigorous stall program to establish Vs - then do the numbers. What's that? the pax want to get off! And it was just being done for their safety.


Based on that info, my students are strongly advised to back off power and IAS anywhere near where turbulence is likely, eg Cb vicinity, mountain shear zones, at lower level if winds >25 kts etc.


Where pilots begin to debate the ins/outs of ASI green arc / yellow arc is one of my peeves. Yellow arc cruise is strictly smooth air, and it certainly isn't likely over many months in Australia where we suffer average ambient temperatures of +20c over standard. Vno is not Va. It can be rough as all the way up to 10k some days.


Continuous flogging of aircraft through low level thermal turbulence will eventually create fatigue in the airframe - just look at the number of C210s that have broken up in flight in recent years. When you have a Va around 120-125KIAS, it's risky to be pushing your luck in rough air at 140-150KIAS.


If you have a more strongly constructed aircraft with a manufacturers LF of say 5.0 - 6.0, then you'll have a higher Va. A PC9 or PC21 sounds good.


happy days,

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great writeup Poteroo....


With the great weather, went back to Cowra today (should have been working) (I did work Monday).


another 2.4h today (1.3+1.1). 1pm, 3pm flight. wind disappeared almost altogether in late afternoon.


improving my landings (bouncing a bit- no balloons today). yield is only about 30% (IE where I don't go crunch).


need to put more duration and progressiveness into the flare. etc etc .


refining different phases bit by bit


flapless landings are easier at the moment- the rate of change of everything is slower without that high drag, high lift configuration.... (it seems).


did a go-around on my own decision today with someone sitting having a cup of tea in the middle of runway. FFS.


No flying for a few days now.


cool air is noticeable !

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A controlled landing beats a fluked greaser one every time . In still air you can use a "this worked OK last time" but you must be ready for anything " to happen and respond to it some times in small amounts and others more dramatically.. Sense and react if and as the circumstances demand it. Nev

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OK yeah. last landing of the day yesterday- just before touchdown I got distracted by a slight yaw, and stopped arresting the descent sufficiently. clunk ...apparently I have not had anything classed as a hardish landing so far though.

its very much a simultaneous multi axis reaction/control thing that has to be mastered. I can always get the thing on the runway though even after a few circuit geometry screwups, too low too high, left right whatever...I can sort out all those no problem. My FI actually asked me (on an excessive length downwind leg) if I had a map of Victoria with me ? funny.

need to also concentrate on keeping the wings level /slight down one side in those last moments.


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I know its easy to say, when I have been flying the same aircraft for 11 years or so, but try not to over control the aircraft.


In "normal" flight situations, the best pilots dont seem to do very much in the way of control inputs they tend to let the aircraft fly itself.

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Excessive and inappropriate inputs create their own problems. Initially, the process will be fairly basic and simplified. It HAS to be or you would be overloaded. Also you don't go doing your initial circuits and landings on a gusty day neither will your first solo be done under those conditions. . Stick with what your instructor is telling you. You will still do the odd clanger when you have thousands of hours but you will be coping with worse conditions. (At times) Nev

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