pylon500

I also did an amphib' endorsment back in April '91,probably in the same machine, 25-0429? out of Proserpine.

Arthur.

Hi Howard

Just out of interest, how many LightWings are out there?I don't want names and numbers, and we don't want to give the to AirServices either! I've been instructing in this one for over 14 years, it's a LW-1 updated to a GR-582 (sn#005!)This was it's second colour scheme (my design ) which caused much debate in the club.Most liked it, but the detractors ended up calling it the "Liquorice Alsort"

Arthur.

Be careful not to confuse wheel shimmy with wheel imbalance, two different problems.Wheel imbalance can lead to vibration annoyance, wheel shimmy can lead to catastrophic failures!!Shimmy can also occour on both nose and tail wheels, but as mentioned earlier, is not quiet as destructive on taildraggers.

Arthur.

Of course the irony here is that for your $130k, you could buy a second hand Piper Arrow that will do 130 knots+, with full IFR, retractable, auto-pilot, four seats and can be parked outside without melting!But we still like our Ultralights?Had a chat to the guy with the Polaris at Narromine and he plans on being the agent for them for around $150k.C'mon Howie, churn out more Lightwings and maybe some Speeds for the long distance boys!

Buy Australian!

Arthur.

Had a look at the Polaris at Narromine, some very nice touches.On closer inspection there is some inovative construction methods in use, in that it's not ALL plastic!

All the control surfaces are actually metal structures covered with fabric, while the tail and sections of the wings are fully covered in metal.Looking at the manufacturers site,I was suprised to see that they can supply the Polaris, and other models as taildraggers!This may seem a brave move, but the company has been running since the 60's when taildraggers were the norm.The taildragger version of the Polaris is definately sexy!!

Arthur.

G'Day Camo, Arthur here,Looking at your first post you say you want to train in the Northern NSW/ South Queensland area?Is this where you is at, or just where you were going to be for the christmas break?(Your member profile does not give a location!)There are some Lightwings in the Sydney area if you reside here, and they're all taildraggers!E-mail me,Arthur.

With 1600 odd hours in the LightWing, I guess I'm biased, but for all round training it's probably the best place to start. From a taildragger LightWing you can go and fly most of the earlier designs around and when you get into a quicker tri gear machine, it all falls into place very quickly.Start with a quick tri gear machine, and you'll find yourself having to do a lot of 'endorsing' to be able to fly any of the affordable planes on the RA-Aus register.Arthur.

Where to comment?I feel the urge to say something, but am not sure how to, without contradicting myself!This leads me to ponder, as an experienced pilot, how could I contradict myself talking about flying and instructing?The truth is, many of the points raised above are valid and sometimes equally so on both sides of the discussion.The real answer, I think, lies in the fact that flying is a very broad spectrum activity and trying to teach it 'by numbers' suffers from the numbers being economised somewhat to appese the book writers.I learned originally in gliders with the GFA, but this was after flying models for years previous to that.During my childhood, my father was a state winning competitve modeller and a gliding instructor.In

this enviroment, I learned all sorts of things about flying,

instructing, techniques and proceedures from listening to him and other

modellers/instructors.Now as a Senior Instructor, I am faced with trying to balance 'the numbers' against variations that I have to come up with on the spot to better demonstrate a learning stage to a student rather than repeating endlessly 'by rote', and hoping they eventually get the idea.To that end I find the only real method is EXPERIENCE.This brings me to one of my gripes being the advancement of instructors.To me, the amount of rote training required presently for pilots wanting to become instructors feels wrong.There

is too much emphisis on trying to achieve the required amount of

numbers, but no consideration on gained experience, we seem to be

trying to teach experience.This puts us in the position of having our new pilots asking the Seniors and CFI's if they can become instructors.With the GFA (in my day) it was more a case of the Instructors and CFI's watching the solo 'young guns' and deciding when and who was ready to go to an instructors course.This

may seem open to abuse and personality conflict, but the truth is, the

gliding movement is still looked upon as being the place with the best

instructional qualities, which is why the AUF was originally based on

the GFA concept rather than the CASA backed GA field.Things

I find out of place are like the fact a trainee instructor has to do

more two seat training with a CFI or Senior Instructor, than a student

needs to, to go solo!Becoming an instructor is about having

flying exprience, knowing what flying really is and the ability to

comunicate and control at the same time.Ideally we are looking for 'naturals'

and CFI's shouild be able to spot them, those that can only learn by

rote should maybe not apply and just stick to flying straight lines

through the sky by numbers.That's my stick in the hornets nest, it's getting late (I'm instructing tomorrow!) so it's off to bed. zzzzzzzzzzzzArthur.

Oddly enough, this is one I learned back in the days of flying radio models.Once myself and on two other occasions watching others, I saw flapped models ( all scale) spin in while turning final to land from a small circuit.Turns out that you may not notice the amout of pitch change that can be associated with deployment of flaps, and even harder to notice while turning!So the situation is that if you are tuning (base or final) and you apply flaps, you are at approach speed (slower than cruise), you are turning (applying 'G'), you will feel the deceleration (which you expect)

but because you are turning, you are sensing many

rate-position-sound-speed changes, then you may NOT notice that you

have increased the angle of attack on the WING (not the fuselarge where you are sitting) and are getting close to a critical angle!The usual clincher is when you apply opposite aileron to roll out of the turn, and stall the inboard wing!The

nose drops, you instinctively pull back on the stick, and the ground

crew walks to the end of the strip to scrape up the mess!!!!Arthur.

Looking up the Op's Manual, it's a little vague?Check sections 2.8,2.9 and 2.13.Basic jist seems to be as long as you did a renewal flight within two years ago, you can still fly!But

the reality is that if you rock up to a flying school or club to hire

and fly, unless your logbook shows flying within the last four to six

weeks, they'll all want you to do a check ride with at least a senior

instructor.If you drive up to an airfield with your own

aircraft, at least one of the local operators should ask to see your

logbook and rego just for their own liability's sake.Once

again the reality is, if you are not known at the field, lots of people

will look over your plane, your rego card and someone will no doubt

want to look at your logbook again.If you complain too much

they may ask you to leave the field, or they will make sure they have a

witness or two of them saying to you "We suggest you don't fly, and if

you do we take NO responsibility for you"As for your actual question, I guess you only have to do one hour every two years, But it will be with a CFI!

I can assure you a plane will flip over in even one foot of water!

(I know!)

This (and most of our) aircraft is kept in a three sided hangar that faces the East.We have a 'Shade Cloth' curtain drawn across the front, more to keep out birds than the sun.For the last two years this LightWing has sat at the front of the hangar and yes, the hub was starting to fade.The irony is that it was the rear hub half that failed.

It's a bit annoying actually, in that I take my students to the prop before each flight as part of our preflight, and spend that time inspecting the blades because they are showing signs of fading.I guess I became a victim of doing a routine, but boy, am I adding to that list!! Actually I suspect that the crack in the plastic occoured suddenly in that the weekend before I saw the crack, I had actually been told about it by the last pilot to fly the aircraft the day before, he noticed an increasing vibration, so landed and found the crack.He called me about it, but never mentioned it's size. As I mentioned in the first prop post, I suspect that the inner steel plate possibly cracked some time earlier, and after growing in size, eventually stretched the hub plastic until it craked.I guess the thing to do at each walkaround is to look at the blade retaining bolts for signs if cracks radiating from under the washers, or signs of the washers having moved.

Arthur.

UPDATE;Have just recieved the new Ultra-Hub for the Brolga containing an assembly and maintenance sheet. Apart from saying you need to recheck torque values after, 1,2,4, and 8 hours of operation, you also need to check every 20 hours and then dismantle the prop every 200 hours.It also suggests replacing the bolts every 1000 hours.Fortunately the blades themselves are deamed to have indefinite life after regular inspection.Arthur.ps, Hub Halves (x2), Pitch Blocks (x6), Bolts (x6), Nyloc Nuts (x6) and Washers (x18) plus post = $353.20.

Grade 8, 80x8 mm, at 1.25 pitchG'Day Tony, yes, feel free to use any of my photos you find on the web.I'm supprised to hear you say the Brolga supplier specify the non A/C bolts?I'm fairly sure we were using the prop as we got it, with the AN-5's shown in the photo. These are only used to retain the blades as the prop is held by fixed bolts coming forward through a spacer on the front of the 912

(this is as supplied by Howie, don't ask me why he ounted the engines half an inch BEHIND the cowl lip?)

We have in the past noticed an odd harmonic vibration at around 4500rpm, but put it down to unbalanced carbies, which we seemed to spend a lot of time curing. I think we'll still use the Brolga as it's a good hard working prop, and with the years I've delt with the Vampires, I never noticed a problem with the Ultra-Props other than lack of performance.Arthur.ps, the brolga guy is currently in Napal.

Trouble happens in Three's!

On doing a daily on our LightWing Last Saturday, I found a crack in the plastic 'Body' of our Brolga/Ultraprop hub. While initially thinking that it was only the plastic with a crack, and that the steel plate within wold be OK, I decided to pull the prop off for a quick look. What I found was bad enough, but when I pulled the prop apart, it was freightening! It looks like the plate had cracked earlier and only when flexed far enough it had split the plastic hub body.The crack is on the rear hub half with the trailing hole having the crack, so I'm not sure if it could be from a prop strike?It could have been from a problem we had some time back with the 912 having odd bad starts in the morning.

When starting cold with choke, the engine would wind, then fire up for about two revolutions and then stop dead very abruptly, almost like a backfire.(Apparently the 912S's are really bad for this?)After completely stripping the prop I found that;

1. Rear hub cracked at one hole

2. Possible cracks at other holes

3. One pitch-block split in half (rear block)

4. ALL other blocks have cracks

5. ALL retaining bolts (correct AN series) show signs of bending

6. Bolt at the failure point was Cracked!

All (but the cracked bolt) had the correct torque at the nuts, but there is a problem in that the bolts torque down onto a plastic surface. The hub kits are usually supplied with normal AN-960 series washers, I'm thinking that we should use a larger washer format to apply the torque load over a greater surface of the plastic to avoid crushing.My only fear in uploading this post is that we could start the same hysteria that occurred with the GSC props.

As I posted in a previous forum, I believe propellers are to aircraft as tires are to cars, they all work, some better than others, they just perform in proportion to their cost, reliability is not usually an issue.As such, I have ordered another hub and pitch block set for the Brolga, I just might notate in our logs to strip, inspect and rebuild the prop every 100 hourly, it would only take about a half hour., and after all, we all rotate our tires don't we?

Arthur.

Currently we are opperating only one plane (we have two) and seem to come up to a hundred hours about every four to five months. In the past when checking the brakes, it was usually the brake cables, the brake lining and the roundness of the drum that required attention.This year is the first time I've seen cracking (metal fatigue?) in the support structure or band itself!

It is possible that the band was refitted at some stage, but not aligned with the rim, then fitted tightly instead of floating a little, which applied the side load that started the crack. Will have to go back through the logs.will be having a lot more work done next 100 hours.

Arthur.

We must be having one of those months!!After the tail spring broke, I noticed one of the tangs holding the brake band had a crack!

This annoyed me a bit, but I got it welded up and we continued flying.Two weeks later while checking the brakes on a daily, I find the other brake band has almost cracked through!In repairing the tailwheel, I had also rebushed the pivot point, and the steering was a bit heavier while the bush bed in.The need for more braking to steer must have hastened the crack!I guess you just have to be extra vigilant with these things.Arthur.

Bearing in mind that the original photo depicts a piece of spring steel, to do inspections on 4130 (chrome-moly), I guess the best resource would be good ol' AC 43.13-2A, try chapters 2 and 7.Generally though, once a steel tube structure has been built, it's enclosed to such an extent that the only inspection option left would be complete re-bagging or X-raying.Both prohibitive for the average 100 hourly! The best you can do is figure out the most loaded sections of the structure and inspect the welds at those points as best you can with a touch and mirror.Anotherway is to look for loose or rippled fabric on the structure, and question why the fabric is not tight? For those that are building, be warey of painting tube structures a dark colour, much harder to find cracks on a dark background!

Arthur.

Had a slightly heavy landing with a student the other day, and the tail leaf spring snapped!

Only minor damage, but makes you wonder just how far do you go inspecting at 100 hourlies?

Arthur.