old man emu

We pulled another Pitts out of a seatainer at Camden yesterday.

It's a Pitts S2B. I was too busy disassembling the packing crates to take photos or to chase its history and future. Might get some pix next week.

OME

I'll see if I can get a drawing done this weekend.

OME

This plane building can be dangerous to your health!

The other day I nearly got involved in fisticuffs with a bloke over the layout of my instrument panel. I've decided that I'm going to install an altimeter, an airspeed indicator, a bat & ball, a combined oil temp/pressure guage and a tach in the instrument panel. The first three instruments are going to be 3-1/4" diamter and the last two, 2-1/4". I was going to place the big ones in a nice triangular pattern in the centre of the panel, and the small ones below and to the left and right of the panel. It would look pretty.

Well .... This bloke went off a treat and begged me not to lay them out like that. He said the ASI, ALT and B&B had to be on the left hand side of the panel and the engine instruments on the right hand side. Considering that the plane is a single seater and the panel is 24" across, I figured even my worn out old eyes would be able to see all the instruments in one glance. Still he kept on. "You'll never know when you might suddenly fly into IMC" Given that I'm a fair weather flier at best, I figured that at the first sign if IMC, I'd turn and run. Besides, Who's building this plane anyway?

I'm glad it didn't come to blows. He's 91 year old and a quarter of my weight. I couldn't bear the horror of the beating he'd give me.

So what do you think. Am I right to stick to my guns, or is he right to stick to convention?

OME

What's happening? Has everyone put up their tools for the winter?

It's getting near the end of the Financial Year, so I'm in the mood to deal.

10% OFF LIST PRICE ON ALL ORDERS FROM NOW UNTIL 30 JUNE.

OME

Kevin,

Please check out the Services and Suppliers forum.

Old Man Emu

I recently purchased a second hand altimeter, fully checked and with Instrument 8/9 certification for $550 from the bloke who does all the instrument work for the mob I work for.

Note that the altimeter from Spruce & Specialty is set to inches of mercury, not millibars. You'd have to get it converted, although most of the altimeters S&S sell can be supplied in mb. Don't touch a Chinese one.

OME

(QED Hardware doesn't carry altimeters as a stock item)

Here in NZ we have a J160 and an Alpi Pioneer 200 , both are charged out at $110 hr,

$1NZ = $AU 0.83

$NZ 110 = $AU 91.67

Who's up for a fortnight in NZ to rack up a few hours?

OME

Kerry said to go to Tower 2 and she'll give you the crank to her T Model

OME

I get annoyed when I go to the doctor's and the majority of mags are old and female orientated. I'm really looking forward to the upcoming Royal Visit by our new Queen. The Woman's Weekly is going overboard with its pre-event promotions. I wonder if the Queen can do something about lifting rationing. It's been ages since the war ended and all the Yanks went home.

OME

What do you do to promote recreational aviation, or light end GA?

The other day I went down the village to get my feathers trimmed by the barber. I pecked through the pile of magazines the barber had for customers to read while waiting for their turn in the chair. The pile contained a wide selection of car and motorcycle mags.

I wondered to myself, " It would be a great way to promote recreational aviation if I dropped off my RAA magazine, and other aviation mags to the barber when I had finished with them."

What do you think?

Old Man Emu

I've got several CAD programs, but I find that eMachineshop works in a similar way to the way I learned to draw plans. It does not have all the bells and whistles of the high range CAD programs ,but I can draw simple stuff with it and then export it in *.dxf format for use in CAM software.

OME

Happy for you getting your wheels done. Jealous that you can get access to the P Scout.

Have a go at those valve springs

My boss reckons that spares for the engine would be like fonding hen's teeth in rocking horse poo.

What is the name? Miss Mogal? What was the rego?

OME

Given the size and weight (but mostly the weight) of a full set of ribs, it's cheaper to cut them here. Also, the drawing can be cut up into sections so I can have separate drawing files for the false nose ribs, compression ribs, end ribs, short ribs where the ailerons are, and the aileron ribs.

I am thinking of getting eMachineshop to do all the metal fittings since they can cut and bend. The postal charge for all the fittings would probably be about $US35. I'l have to see how much the manufacturing cost will be.

OME

You would think if it is the high revs causing noise that rotax engines would be a lot louder.....

You can also consider the amount of noise a 2 litre/4cylinder engine will make compared to a 4 litre/4 cylinder engine, simply due to the amount of gas pushed out during each exhaust stroke. (Notice I didn't say that it's due to the bigger "bang" during the power stroke.)

The major source of noise from an airplane is caused by the prop tips, and this is a product of the blade diameter. That's why putting a three or four bladed prop quietens a plane down. The extra blades share the engine power, so each blade does not have to be so long. The tip does not have to travel as great a distance per revolution, so it is slower. It all boils down to the old:

speed = distance/time, where the distance = pi x diameter.

OME

In my limited knowledge if you had the aircraft bought back to specifications by a LAME then it could be done. Has anyone performed such a feet and what pitfalls did they find?

All things can be done, provided that you are prepared to fork out the money to get the jobs done. The question boils down to: "Is it economically feasible to do it?" You must consider which side of the equation has the most dollars:

Price of Airplane + Cost of C of A etc Sale Price of Airplane

OME

But I'm an EMO EMU. I've only got black nail polish.

It would appear from CAR 155 that there is no legal impediment to deliberately stalling an aircraft at any height, since a deliberate, straight and steady stall is not deemed to be an acrobatic manoeuvre. However, the lowest altitude that it is legally permissible to engage in straight and steady flight is 500 ft AGL.

Therefore, the lowest altitude that one can deliberately stall and aircraft from straight and steady flight is 500 ft plus the height expected to be lost in the recovery process.

It is a wise pilot who acknowledges the safety value of clear air beneath the aircraft.

If one could trace the origins of this 3000' limit, it seems most likely that it arises from someone's failing to read subregulation 2 of CAR 155 and jumping straight to subregulation 3.

OME

Yeah, well that was a wasted effort. I wasn't happy with the result I got from measurements off the drawing I did, so I went back to basics. One of the CAD programs I use will read a text file which contains a list of X,Y coordinates. and then draw a shape from them. So I used the data from the plans to write the file, but this time I converted the Imperial measurements to Metric before I added each one to the file.

I don't know why, but the curves produced by the metric measurements came out virtually spot on, with no unwanted bumps. I think that this could have been helped by the fact that I had draw the shape so often that I knew where to look for errors in thepublished data.

After I had my initial drawing, I saved it as a *dxf file, and opened another, simpler CAD program calles eMachineshop [ www.emachineshop.com ]. This program has few of the advanced features of the other program, but its procedures fro drawing lines and making curves are much easier for a novice CAD user. And it's free

After several attempts, I have finally come up with a drawing that I can use to great the G-Code for the CNC machine. One thing that I did notice was that the depth of the spars was greater in my drawing than on the original plan. I gave this some thought, and figured that if the spars were the correct distance apart, then I could locate the wing attachment lugs on the fuselage to suit the depth of the spar.

Since I have the drawing of the whole rib, I can do some cut and paste work to produce the drawings for the false nose ribs, the ailerons, wing tip, copmpression rib pieces and the shorter ribs in where the ailerons are.

OME

Done me money again!

OME

The money at work is on its being a Pobjoy.

OME

Yes. Postage and Handling on low cost items like this makes the purchase of a single item ridiculously high. That's why it's best to buy from the suppliers who support this website. They spread the P/H over many items so that the price you pay for your cheap item is still lower than what you would pay on the open market.

Suppliers who support this website try to keep overheads down and don't agree with putting 300% mark ups on the items they sell. Because of the low volumes involved, most suppliers find that the customer has more ready cash than the supplier.

OME

Kaz,

One of the first things to learn about vehicles of all sorts is that it is rarely a big thing that causes a vehicle to misbehave. It's always something dead simple, and usually cheap to fix. Didn't Peter Brock fail to finish at Bathurst one year because of a twenty cent O-ring?

OME

You bloody beauty! I have found that if you bother to ask around and talk to people all sorts of things crop up.

Your next task is to go to this bloke's place and take heaps of photos and find out the type of engine it is. I'll bet it's a Kinner.

You are one lucky bastard!

OME

OK. I've emailed you the details of a bloke to see in Tamworth.

When I went to the bike shop this morning, I only got a little bit of info.

1. The suppliers of the spoke and rim should have sent you a lacing pattern which says how many crossovers you need to make. Better get back onto them if you've got no other info.

2. The more crossovers, the stronger the wheel.

3. It is possible to lace a wheel as I originally described, but that would be the weakest assembly.

4. The longest spokes are used for no crossovers. The spokes get shorter as the number of crossovers increases.

OME

I like Kiwi's explanation. It's simple, it allows for Murphy's Law, and I bet it comes from experience.

OME