pylon500

<div style="">You could be right!?<div style="">I thought Zenair manufactured 'kit' floats, but their site now only shows finished ones?<div style="">http://www.airplane.cz/pages/floats.htm

<div style="">You could try here to make some wooden floats;<div style="">www.ultralightfloats.com/index.htm<div style="">This link will give you an idea of building a set of glass kit floats;<div style="">www.ultralightfloats.com/PDF%20Files/Composite%20construction%20instructions.pdf

<div style="">Try this site and go to the 'Float' link;<div style="">http://www.aerocompinc.com/<div style="">Other than that, as you say, there's not much out there?<div style="">I could suggest that if you are down the Bankstown way some time, drop in and have a look at some BIG floats (under Beavers) to get some ideas for making your own!<div style="">Arthur.

Hey 'Cri-Cri', why didn't you say hello while you were talking to Garry at The Oaks? Would have been good to put a face to the monica!I was the one instructing all day in the LightWing.Arthur.ps, how do I go about getting a ride in the allegro? We (the club) have been looking for something to replace our two stroke lightWing

I hope this remains the case as I feel there could be some misconceptions here.The best floatation device on most aircraft is the wing, if I was ditching a high wing aircraft it would me nice to be able to step out onto the wing and arrange dinghies, supplies and epirbs before the plane sank.If the aircraft remains upright, you will have to exit underwater and surface, then decide if you want to go under again to grab what you can.Knowing the way the SkyFox windscreen is fitted, it will most likely implode on impact, flooding the cabin in about 5 seconds if upright.As for having a rope attached to the plane, remember, once it fills with water, it becomes a 300kg sinker.If you want a sea anchor, use a sea anchor!Sorry about the rant,

Arthur.

C'Mon Glen, you're not getting all cynical on us are you? I've been flying in a Gazelle with half fuel and a couple of 'average' blokes on board, and I thought 300 fpm was doing all right! I'ts not like it was 40C outside, I thought it was only about 37C!! Still there's some good thermols around everly.

Arthur.

You're forgetting that the aircraft would be upsidedown, you need to worry more about what you could tangled in, in the roof like headset leads an the like .Just remember to take a second and think before undoing your seat belt!

Arthur,

Speaking from experience, I can say that, should you have the misfortune to have to ditch, you are more likely to survive in a high wing aircraft because most planes will overturn on impact.Once the Gazzelle had gone on it's back, you would most likely have nearly two minutes of floating on the wing before it sank, and in an emergency you would be suprised how quickly you can get out of a small openning!

Arthur.

I've noticed this as a harmonics thing in a few aircraft.The first time I flew a sapphire it did a wheel shake as I was going up through about 100 feet.I was sure something was about to fall off.

I've since noticed it in Drifters, Jabirus, Cessnas and other aircraft that use a common leaf spring gear, or any other type of single cantilevered gear leg.

Arthur.

Is it actually the brakes at the wheels not working, or is the cable so stiff that you get no movement?Try to force some grease down the cables (talk to someone at an old motor bike shop about cable oilers)Arthur.

The EG-33 was actually fairly popular in the States in the bigger homebuilts, (usually supplied by Eggenfellner) like the 'CompMonster'This is an earlier Subaru engine of 3.3 litre displacement.Looking at the Eggenfellner site though;http://www.eggenfellneraircraft.com/Aboutus.htmIt now looks like he mainly deals with the new 3.0ltr H-6 found in Austarlia in the Outback series.I don't know what it's engine type designator is, EJ-30 maybe?Arthur.

Just out of interest, what sort of problems did you come across when working at Subaru on the EG-33 engine?I have one, still in the original car!And I would never take it out to put in a plane, the car is too good! Arthur.

Chasing info on gliders and found this...http://www.boonahgliding.com.au/subaroo.htmCan't seem to get my links active?Arthur.

I'm running an INVERTED 582 and used to run on unleaded mogas.I

was fortunate that I was rebuilding my plane during the time of the

fuel adulteration problems but did find the odd problems starting and

often had fouled plugs running ULP.Combine this with using

Avgas at one of the Nat-flys and on the way home I started getting some

overheating and what sounded like detonation!?On landing at Bathurst to refuel my plugs were completely fouled, so after refuelling with ULP and some new plugs I got home OK.I now run PULP (Caltex 98 if possible) and my motor runs like a clock.I have only used Castrol Super TT, and now use it's replacement Active 2-T, I may try a synthetic one day.Arthur.

On something like a Thruster, I tend to feel the extra power is absorbed by the extra weight incured by fitting a 582.If

you fit a 582 you usually also want to fit electric start, a battery, a

couple more instruments, a 'C' box and probably a three blade composite

prop.Not everyone also wants to fit oil injection!It

can also have some weight and balance effects, I once tried to instruct

in a Thruster fitted with a 582 and it flew like a dog!Better to keep light, and save money. Tony could probably give a better insight.Arthur.

In our field of aviation (low cost and light weight) I would have thought the heavier more expensive (and harder to find) square tube wouldn't stand much chance.I

tend to look more from a production point of view sometimes, and had

thought of square tube, but I would have to use enough of it to make it

worth while.I'm still thinking.....Arthur.

As a former RAAF 'Aerostructures' repairer with a bit of

background in bonded structures, be prepared to pay lots of money for

not only the exotic epoxies, but the infrastructure that goes with them;Freezers,Vac bag systems,Autoclaving systems,Cleansuits,Etch chemicals.That's not to say it's impossible, but a purely bonded Primary structure means you have to be real sure that it all sticks together.The main problem with bonding aluminum (or any metal)

is that you need to create some form of textured surface for the

adhesive to hang onto, many think that bonding is like that trick where

you can hold two polished surfaces together with a drop of water.Unfortunately this has no shear load ability, and this is the most typical load requirement in aerostructures.Many of the repairs I do, stem from the use of slightly acidic (or alcalinic) epoxies to help etch at the bond site.This

can work for a while, but eventually heat and flexing movement will

allow moisture to enter the join and combine with acid residues to

attack at the bond surface.In a recent example a Cessna 182 of about the 70's era (that's a later one!!) turned up with bulging at the ribs on the leading edges.The early (50's & 60's)

Cessnas' had rivetted ribs in the leading edges, the later ones are

bonded for a quicker and better finish, but this one had de-bonded most

of the ribs and started to corrode the leading edge skins.Remember, I'm talking here about primary structures, you really need to say where you want to go bonding stuff....There are lots of discussions about this sort of thing on a really good homebuilders site in the US;goto http://www.homebuiltairplanes.com/forums/Arthur.

All basically makes sense, the Clark Y has turned out to be a

fairly good compromise all round, although your reason for using it ie;

simple to built, is actually limiting you a little.When building a wing, we often like to set it up on a table to get it square (or block up the trailing edge for washout)

but when you think about it, we only support it on the spars, therefore

the flat bottom on the leading edge ribs is not required mechanically

and is detrimental to aerodynamic preformance at speed.Basically

at higher speeds when the camber line starts to dictate a low or even

negative angle of attack on the chord line, you start to get flow

separation under the wing causing drag.If you go to a Clark

YH with a raised leading edge profile, you get better top speed PLUS

you can end up with a more docile stall.From what you've

posted maybe you want to build a metal version of Mike Arnolds AR-5,

maybe have a look at some of the Davis series of lightplanes (DA-8,DA-9 and on)Arthur.ps, Try to keep all your posts in the one thread, the administrator may relocate this with your original post if you pm him.

Do you have a scanner or cad package that you can upload a three view drawing of your idea?Some thoughts;I was getting 70 kt cruise from a 503 in a large, strutted, highwing, all aluminium 'Bird-Dog' lookalike (see my avatar)I keep my VNE to 85 kts 'cause I've never done any calculations for it!My stall is around 32 clean at idle, but with flap and power, I can maintain level flight at 27 kts!What I'm saying is...Aim higher!!Free Lift? Remember, lift is generated on the TOP of a wing, you'll get more lift with the airflow over the top.Why should your firewall create drag?If you cowl the engine and round off corners at the exits, drag should be minimal.To cut down on some of your start point research, have a look at some plans of other similar layouts and improve from there.Try the Hummel Bird.Feel free to pinch some structural ideas from;http://www.pbase.com/pylon500/rootArthur.I still can't get some of the HTML to work!? :-(

If you think we've got the bandwidth, I'll upload most of my building histories!Meanwhile, I've added some more photos to my Yahoo LR-2 site.Arthur.

No, Just a couple of cans of Baked Beans, and WATCH OUT!

I'm into building and I've found some sites to host photo albums Building my 'STOLLITE' here;http://www.pbase.com/pylon500/rootAnd my new project, the 'LR-2' here;http://au.pg.photos.yahoo.com/ph/pylon500/my_photos

Arthur.

Cable update;While manouvering our aircraft into the

hangar the other night, a loud bang was heard which we thought was the

tailwheel turning.We then noticed one of the tail wires

appeared loose, and on inspection found the cable swage had corroded

away under it's heat shrink cover!After all heat shrink was removed, it was found this wire was the only one with an aluminium swage?New cable with propper nickel plated copper swages fitted.

Arthur.

When terminating (the technical term)cable ends, yes the Nicopress sleeve (usually copper) crushes the loop ends of the cable at a higher strength than the cable itself.To

get a neat fit around the Thimble when using Nicopress, if you have the

standard tool, you should be able to do three squeezes on the ferrule.With

the cable threaded around the thimble and fed back into the ferrule,

arrange to have about one and a half cable diameters protruding from

the ferrule, and the ferrule pushed tightly against the thimble, set

the first swage in the middle.You will notice that the ferrule will 'grow' in length, this helps to tighten the loop.Swage

again near the thimble, leaving a small amount of the ferrule

protruding, to both tighten the loop and leave a tapered oppening for

the cables to enter the swage (don't pinch on the edge)Finally, swage the remaining amount of ferrule (also not on the edge) to leave about half a cable diameter protruding from the swage.If you have a wide jaw swager, start away from the thimble first, then set near the thimble.Things to consider;NEVER swage at the same place on the ferrule twice.Don't try to swage onto plastic coated cable, if you get a ferrule that fits, you've got the wrong one!Putting heat shrink over a swage is ill advised as it will hold moisture and promote corrosion.For more detail goto;http://bosunsupplies.com/NicopressSwage.cfmOr if you can read German, (some good diagrams);http://www.schmidtler.de/html/ht_technik/seile.htmAs for EYE and FORKends, these should never be set with a Nicopress tool Any

kinks in the swage tube can form a stress raiser and start cracking

strands, use the correct rotary swage tool or full length hydraulic

press swage.(I have seen a system that used full length jaws powered by a pneumatic hammer, it seemed to work once you got the hang of it)End tonights lesson.Arthur.ps, I don't know why I can't use most of the site shortcuts?

Given a choice between using the GSC prop supplied with the aircraft, or a Brolga, I'll take the Brolga!

I figure this is the place to put forward technical/maintenance questions, so herfe goes.This question is aimed at people using Brolga props.Many of you would have read my thread about the cracked Brolga (Ultraprop)hub we had.Prior

to finding the crack, we had begun to notice an annoying vibration we

werew getting at some airspeed/rpm combinations, typically at 60kts

with around 4500 rpm in level flight with our GR-912 LightWing.Initially

we put it down to an unbalanced prop, but it proved to be within

limits, so we then suspected an imbalance between the carbis'.We also looked at timing and gearbox backlash to no avail and ended up doing the GA fix and said "Don't fly at that RPM!"About then we had the prop hub crack and figured problem solved!But

this was not to be, as once the new hub was fitted, and the prop

balanced, we took off, only to have the same vibration come back. We then found that a nearby GR-912 with a Brolga prop was doing the same thing.We

have an 80hp 912 with a three blade prop running 14 blocks, the

vibration does not actually occour at just one rpm, but more at a range

of 'Loads' on the prop.

As mentioned earlier, we can get the vibration anywhere from 60kts and 4500rpm up to 70kts at 5200rpm.If

we had a manifold guage, it may show the vibration occouring at a

certain pressure which would represent the amount of load the engine is

under (a relaxed cruise?)My theory is that when the prop is not under a high load (like climbing or flying fast), some form of resonance is exciting the blade tips and getting a 'tuning fork' effect going which feeds back as a vibration?I would like to hear from others runninng Brolga props, if they have had similar vibrations?From there we can try to determine the actual cause of the vibration and find a way to control it.As

a side note, back in 2002, I was in Germany and had a fly in a Technam

Golf, and although the translations were interesting, when the

instructor pointed to the tacho, which had a yellow arc between 4200

and 4700 rpm, and said "Nein, nein", I got the idea.And

he was right!, after joining circuit I slowly reduced power and as the

engine came down through that rpm range, a very strong vibration ran

through the aircraft before he grabbed the throttle and closed it

quickly!Arthur.

If doing maintenance on GA's, CASA now want to see authorisation via

the manufacturers maintenance manual, or failing suffiscient

information from same, a Reg 35 Engineering Order to justify basically

any work done beyond a grease and oil change.This must then be

signed for by, the guy that did the work, his supervisor, the hanger

maintenance authority holder as well as being signed and approved by

the Reg 35 guy!What CASA doesn't know is that we all get our ideas from AC 43-13! A

one man band maintainer can usually do about 4 hours actual work a day,

the rest of the time is wasted trying to prove that he actually knew

what he was doing, trying to keep his inventory up to date (in case he gets inspected),

getting all his release certificates in order and trying to convince

his customers that it really does take 4 hours of 'work' time to change

eight spark plugs!!

And we wonder why GA is so expensive and dying?!!

Arthur.