old man emu

This might keep the house cooler and aircon charges down, but how will it affect the air currents?

If the roof coating resulted in a higher albedo than the original, then infrared radiation (what makes things hot) would be reflected before it had the chance to increase the temperature of the roofing material, which in turn would provide less temperature gradient between the roofing material and the air in contact with it. The air would not heat as much as it did with the original roof surface, so it would not tend to become less dense and rise. It is rising air that initiates heat circulation and wind generation in the atmosphere.

 

 

Well, Sydney was established where it is because it provided a much safer anchorage than Botany Bay, which was going to be the site for the settlement, based on the glowing reports of Joseph Banks. It was too bad that after leaving Botany Bay, Capt Cook didn't poke his nose into Port Jackson (Sydney Harbour) before heading home.

 

As to the weather, if you read the diary entries for January 26, 1788, you will learn that after a very hot day, the new arrivals encountered massive thunderstorms with heavy rain and strong winds - a Southerly Buster, typical for late January. I wonder how the settlement would have fared if the First Fleet was still anchored in the unprotected waters of Botany Bay on that day.

 

 

Finally found a good pictorial description of the movement of air masses in the Sydney Basin. The material was prepared about 18 years ago, but it still reflects the current conditions and the basis for my querying the adverse effects of massive residential development in the south-west of the Basin.

 

Air Pollution in Sydney Basin

 

Please don't comment on the fact that the site it got this from is an Anti-Second Airport one.

 

 

We have some skilled navigators here

As always, Off Track, Over Time.

 

 

RTFM,

 

Please advise the following details of the nutplates you require:

 

a. Thread size of the "nut".

 

b. Spacing (Centre to Centre) of the holes through which the nutplate fasteners go.

 

c. Do you require the nutplates to be steel or Corrosion Resistant (Cres)?

 

In relation to the rod ends:

 

a. Male or female

 

b. Bore of the hole in the bearing

 

c. Head diameter

 

d. Length from centre of bore to end of threads

 

e. Thread - diameter and pithc

 

f. Left or right hand threads.

 

g. Race - ball, brass, chrome steel or stainless

 

h. Ball - Chrome steel or Stainless.

 

With this information we can work out the Heim Part number so that you can order the correct ones.

 

 

As a regular viewer of the National Rainfall Radar page on BOM, I often notice a concentration of cloud/rain/storms around Sydney, Melbourne and the built up areas around Brisbane/SEQ, especially with a bit of temp and humidity around.

I can't speak for Brisbane, and the poil of da sout, but you have to live in the Sydney Basin to understand the movement of thunderstorms from the southwest to the north east. There are three major rivers around and through the Basin: Nepean/Hawkesbury, Parramatta, Georges. Thunderstorms develop on the southwestern slopes on a line roughly between Goulburn and Bathurst. As they move in a northeasterly direction and cross the Great Divide, large cells break up and those formed near Goulburn tend to track from Picton to Campbelltown down the Georges River catchment. Those that form along the Golspie Booroowa line first move down the Nepean Valley, and may split with the daughter cells going down the Parramatta River. So the heavy rain falls northeast of the Campbelltown to Bankstown line; along the Nepean/Hawkesbury valley, taking in The Hills District and Central Coast.

 

In the past, Sydney's relief from high summer temperatures was the Southerly Buster, which tracked up the coast from the Illawarra, bringing strong winds and short, sharp periods of heavy rainfall. The effects of the Southerly Buster were not seen much more than 20 kms from the coastline.

 

The majority of residential development in the Sydney Basin is occurring away from these natural storm paths. As a matter of fact, much of the southwest of the Basin, from Bankstown to Camden, Camden to Penrith is in a rain shadow.

 

Hence to original impetus for this thread.

 

 

Tesla's storage battery system in South Australia has shown itself to be a motza better than traditional power generation methods for dealing with above base level demands.

 

It was always only a matter of time before storage batteries became efficient enough to be an economically viable component of the electricity supply grid. And I imagine that the current price of a domestic solar power system would be way below what it was 15 or so years ago.

 

Because of the astronomical price of electricity last summer, this summer we have hardly used the air conditioner in the house. Great comfort in 35 - 40 degree heat ... NOT!

 

 

There are a few facts surrounding this incident that we do know.

 

1. The pilot had approx 9000 hours total time, of which about 8000 were on floats, and a lot of that in the Canadian bush

 

2. He had flown for Sydney Seaplanes for a few years, then had about two years overseas, and had been back here working for Sydney Seaplanes for about the past two years.

 

3. The aircraft are well maintained, both at their water base and at Bankstown.

 

4. The internal control cables were gal wire, with stainless used down to the floats. Inspection of the cables is included in the maintenance schedule for the 100 hourly.

 

5. The plane entered the water vertically.

 

6. The floats did not bring the plane to the surface as one would expect if it went into water 40 feet deep.

 

7. The seating arrangements were:

 

Row 1 - Two individual seats, Pilot + one seat

 

Row 2 - Bench seat, 3 Pax

 

Row 3 - Hammock seats, 2 Pax.

 

The disposition of the pax has not been released.

 

8. The flight was a 20 minute milk run in VFR conditions.

 

The only difference I can see in the wind pattern is that on the day of the incident, the wind around the time was changing from a generally southerly direction towards the east (slightly), whereas the usual afternoon winds are north easterlies, but I haven't got the data for the time of incident.

 

 

This topic is of particular I interest to me because my house roof will soon be due for a repaint. When I built the place in the early 80s I made a compromise between most efficient (glossy white) and blending in with nearby trees, so I chose mist green.

An interesting choice you made there.

 

Why are trees green? Because

 

The colours of the visible light spectrum are: ROYGBIV, which puts green at the mid-range.

 

Pigments absorb light used in photosynthesis

 

In photosynthesis, the sun’s energy is converted to chemical energy by photosynthetic organisms. However, the various wavelengths in sunlight are not all used equally in photosynthesis. Instead, photosynthetic organisms contain light-absorbing molecules called pigments that absorb only specific wavelengths of visible light, while reflecting others.

 

The set of wavelengths absorbed by a pigment is its absorption spectrum. In the diagram below, you can see the absorption spectra of three key pigments in photosynthesis: chlorophyll a, chlorophyll b, and β-carotene. The set of wavelengths that a pigment doesn't absorb are reflected, and the reflected light is what we see as color. For instance, plants appear green to us because they contain many chlorophyll a and b molecules, which reflect green light.

 

 

Optimal absorption of light occurs at different wavelengths for different pigments. Image modified from "The light-dependent reactions of photosynthesis: Figure 4," by OpenStax College, Biology (CC BY 3.0)

 

Each photosynthetic pigment has a set of wavelength that it absorbs, called an absorption spectrum. Absorption spectra can be depicted by wavelength (nm) on the x-axis and the degree of light absorption on the y-axis. The absorption spectrum of chlorophylls includes wavelengths of blue and orange-red light, as is indicated by their peaks around 450-475 nm and around 650-675 nm. As a note, chlorophyll aabsorbs slightly different wavelengths than chlorophyll b. Chlorophylls do not absorb wavelengths of green and yellow, which is indicated by a very low degree of light absorption from about 500 to 600 nm. The absorption spectrum of β-carotene (a carotenoid pigment) includes violet and blue-green light, as is indicated by its peaks at around 450 and 475 nm.

 

So, the best choice for a cool roof colour could well be Misty Green.

 

 

And I guess they skimped on not lagging the pipework. ?

Naturally. Built to a price, not to a standard.

 

 

The effects of colours on composite materials is well known in aviation. That's why Jabiru warns owners against using anything but white for large areas of their aircraft. I suppose that if you wanted a snazzy paint scheme you could do it in the undersides of the plane, a la warplane camouflage.

 

 

 

My wife has said, "You can tell this kitchen was designed by a man", of every house my wife and I have lived in.

 

Our current house has the hot water service 10 or more metres from the area closest to the kitchen, laundry and en suite. There is a perfect alcove outside each of these rooms where a water heater could be placed.The only bathroom close to it is the family bathroom which, being Darby and Joan, we don't use. We waste heaps of water waiting for hot water to reach the kitchen sink or en suite shower. (Wash in cold water).

 

 

An interesting paper on the subject, written in 1992.

 

High-albedo materials for reducing building cooling energy use (Technical Report) | SciTech Connect

 

 

The fault lies with the people who do the appearance design of these buildings. After all, they are calling for dark grey roof tiles, which are made by adding colouring compound to the brick pre-mix. They could just as easily call for terracota colours and the manufacturers would simply change the colouring compound. Same for the bricks.

 

Why are the buildings on the Greek Islands, such as Santorini, white? Why do men in the Middle East go about in white clothing? It's all about taking advantage of albedo rates.

 

We did develop a building style suited to a hot, dry climate,

 

 

but you can't have houses like this when developers want to cram as many house lots as they can per acre as they have done in Gregory Hills, near Camden

 

 

 

This was posted on 28/12/17, so it might be the video referred to:

 

 

To cop a link, highlight the https:// ; Right click to copy, then go to your reply in the thread and click paste.

 

 

If you fly gliders out of Camden, or use the airspace southwest between Bankstown and Camden, I wonder if you can give me some information?

 

Have you noticed any changes in the strength or direction in the winds, or in the behaviour of thermals over the past five years or so?

 

The background for my question is that, over the past five years, there has been an explosive increase in the area which has changed from pasture land to residential use. The majority of houses which have been built have dark coloured roofs.

 

What I am wondering is, "Has the heat stored in these dark coloured roofs due to their low albedo resulted in increased heating of the air moving over the residential areas, thereby increasing the size and strength of thermals, and increasing the strength of the afternoon nor'easterlies.

 

Albedo is the measure of diffusive reflection of solar radiation out of the total solar radiation received by a body. A high albedo means it reflects a lot of solar energy and a low albedo means it absorbs a lot of solar energy

 

Here are some sample albedo values. The range of possible values is from zero (totally unreflective) to one (fully reflective).

 

New asphalt, 0.04 - 0.05

 

Aged asphalt, 0.1 - 0.12

 

Bare soil, 0.17

 

Deciduous trees, 0.15 - 0.18

 

Green grass, 0.25

 

Aged concrete, 0.2 - 0.3

 

New concrete (traditional), 0.4 - 0.55

 

New concrete with white portland cement, 0.7 - 0.8

 

Water, 0.03 - 1.0

 

Soil (Dark/Wet) 0.05

 

Soil (Light/Grey) 0.4

 

Sand 0.15 - 0.45

 

galvanized steel - 0.24

 

terra cota tile - 0.28

 

tar & gravel - 0.33

 

Notice that the good old terracotta tile has an higher albedo than trees, so the old areas of Sydney might be cooler than the the bush they replaced.

 

And I'll castrate the first bloke who introduces libido to the discussion.

 

 

After watching the story on TV, I don't think the problem is the nags in the paddock. It's the old grey mare in the house.

 

Animals soon grow accustomed to noise and, like us, ignore it. Expose them to it for a few days (with the owner present as a calmative for the horses) and the next week they won't even stop grazing as a plane goes over.

 

 

Here's another example of "Love thy Neighbour, but not in my backyard".

 

Why drive to work when you can fly?

 

www.cairnspost.com.au/news/cairns...work.../1e39acec726b7b2fed2ba6ba1b21dccd

 

 

Vev, the mass well back and high is just what you don't want.. It would tend to flatten the attitude and make recovery difficult. Nev

FH, stop repeating yourself. Stall/Spin Studies Relating to Light General Aviation Aircraft

 

 

At a wine merchant's, the regular taster died and the director started looking for a new one to hire.

 

A drunkard with a ragged, dirty look came in to apply for the position. he director of the factory wondered how to send him away. He gave him a glass to drink.

 

The drunk tried it and said:"It's a Muscat , three years old, grown on a north slope, matured in steel containers. Low grade, but acceptable."

 

"That's correct", said the boss.

 

Another glass....

 

"It's a cabernet, eight years old, a south-western slope, oak barrels, matured at 8 degrees. Requires three more years for finest results."

 

"Correct."

 

A third glass...

 

''It's a pinot blanc champagne, high grade and exclusive,'' calmly said the drunk.

 

The director was astonished.

 

He winked at his secretary, secretly suggesting something. She left the room, and came back in with a glass of urine. The alcoholic tried it.

 

"It's a blonde, 26 years old, three months pregnant; and if you don't give me the job, I'll name the father."

 

 

C'mon Yenn. Which bit of Post # 8 did you like?

 

 

I hope the govt doesn't do a "Holden" and simply throw money at aussie owned schools to keep them viable.

If the Government diverted the money CASA wastes on destroying Australian aviation through the "Death by a Thousand Cuts" to bolstering Australian initiative in this area, then the schools would be rejuvenated.

 

If the schools form their business plan revolving around predicted losses and bailout money it won't end pretty for anyone.

But these small businesses want to develop their business plans based on the income they can generate by conducting there core business activities minus the costs of conducting that core business. It is CASA and a hundred other State and Federal departments that are ballooning the cost side of the equation.

 

Another thing that has struck me when I deal with small businesses is that people who are good at some task set up a business to carry out that task, but have no idea how to manage the business with a view to promoting its growth, or even to maintain its status quo.

 

 

the chinese gov doesn't want foreign pilots taking all the good paying pilot jobs, that's how communism works.

That comment is way off target. China has, in recent years, "demilitarised" is air space for use by civilians. With the growing wealth of individual Chinese people (look at the number of Chinese tourists travelling the world) the use of previously prohibited airspace is increasing. Not only are the Chinese buying into flight training here, they are also buying into our light aircraft manufacturing industry. They are following the post-WWII Japanese example and reverse engineering the products of other Nations. How 50-50 do you think Brumby's arrangement with the Chinese really is? I don't see Brumby calling out for workers to make their planes in Cowra.

 

 

Must have been the cut and paste.

 

The first picture is a bloke flat out on his back on a hospital gurney with an alcohol drip in his arm and hooked up to an ECG.

 

The second picture is a woman with long black hair and two of these stuffed on the front of her diaphanous T-shirt.

 

 

 

My boss (female) emailed this to me:

 

 

Hold my emails until further notice,as I am in hospital. I was badly attacked by a woman in an elevator. A witness got her photo.

 

 

I was in the elevator when she got in. I was casually staring at her boobs when she said, "Would you please press 1."

 

So I did ... and I don't remember much afterwards. May be out of the hospital in a week or two.

 

I chuckled at the misinterpretation of the question.

 

I wonder what sort of trouble I would be in if I had sent this to my boss (female).