I’ve long been of the opinion that the sale of fireworks to the general public should be stopped in favor of organised displays. Every year it seems two or three neighbours to the rear of my house decide it would be a great idea to use category 3 fireworks which have a safe operting distance of 25m on all sides! ie: a 50m (164ft) That means that, within our tiny back gardens, not only are they in the danger-area, the are putting myself and most of the street within the danger area.

The public at large in this country just do not have the discipline to behave responsibly with what are in effect dangerous pyrotechnic devices. Class 2 fireworks which are designed for moderately sized gardens would be more acceptable and would not put others at risk as much.

But then there’s a new underclass of complete idiots to think about.

These are the type of idiots who walk into California Wines on Tonge Moor Road, Bolton, Greater Manchester and touch-off a 200-shot rocket display firework. Luckily the shop owner was able to push the launcher outside the shop but his 15-month old baby had to be taken to hospital to be treated for the effects of smoke inhalation.

I happened to browse across a news story today which suggests that the Mosul Dam on the Tigris river in Iraq is in imminent danger of collapse. Apparently, a 2006 report by the US Army Corps of Engineers indicated that the foundations of the damn, consisting of a soft gypsum were being eroded and needed constant maintenance. The latest report highlighted in this Washington Post article tells of US fears that the dam may collapse at any moment. It is projected that up to 500,000 people could be killed if the dam were to breach.

Looking at the position of the Dam in Google Earth and assuming I’m seeing the topography correctly, it could cause a flood down the Tigris into Mosul itself (this is presumably where the high potential casualty figure comes from) I assume the US Army are particularly worried about their troops and equipment in the area.

Aside from the potential for direct loss of life, the Dam provides electricity for about 1.7 million Iraqis living in Mosul.

The US Army Corps of Engineers are recommending that the partially completed damn downstream is finished in order to provide a stopgap while the Mosul Dam is repaired.

You may have seen on the TV News that a British icon of the Cold War has taken to the skies again after 13 years.

XH558, first flown in 1960 is an Avro Vulcan B.2 nuclear bomber. The aircraft is unusual in that it is a large (about the size of a Boeing 737) tailless ‘delta’ design. It’s four Bristol Siddeley Olympus turbojets are well remembered from airshows where they produced their unmistakably loud sound.

XH558 was finally retired from display flights in 1992 and was delivered to Bruntingthorpe aerodrome in Leicestershire the following year. There, with the help of many public donations and the Heritage Lottery Fund, she has been restored to airworthiness culminating in her first test flight on 18th October 2007.

Here we have a video of her return to flight. She makes a noisy and swift takeoff due to her reduced weight; the heavy military avionics and system have been removed and replaced with a modern avionics suite suited to her new display role.

Almost immediately after takeoff, XH558 seemed to be throttled back, this presumably to avoid overspeeding the still deployed undercarriage. I’m informed the undercarriage was retracted later in the flight but I would expect the flight crew were working through operations in stages for the purposes of testing.

It’s great to see a Vulcan flying again, after some more test flights, XH558 is expected to join the display circuit in 2008.

A good description of the return to flight can be found over at Thunder and Lightnings

The Vulcan Operating Company website is here.

On a personal note: When the flight restoration effort began nearly ten years ago, I was extremely enthusiastic about it. Now, while my enthusiasm remains, I feel there is a cruel irony in that while we can return this one British built aircraft to flight, this country no longer has an extensive aviation industry. Indeed, the majority of the industry that once made us great and produced this aircraft domestically is now gone.

I’d consistently forgotten to post about this for over a month but here we go now…

An Industry Week article last month pointed out that Colarado State University has developed a new method for the manufacture of photovoltaic solar panels. The method is both low cost, approaching $1/watt in manufacture and $2/watt to market and high-efficiency, typically 11% to 13%.

The new cells use a cadmium telluride construction rather than the common silicon crystalline design. It is pointed out all over the web that CdTe is toxic if released to the environment so any such solar cells would have to have an end-of-life disposal plan in place. However, these cells could potentially generate power for 40 years or more (some of the oldest operating photovoltaic cells are rumored to be ~80 years old now)

If these panel materialise on the market at £1/watt ($2/watt) they will effectively cut the cost of photovoltaic solar panel installations in half. This could mean cost break-even times shorter than 5 years.

Ever since ‘mail marketing’ took off in the early nineties, I’ve been getting a steadily increasing volume of useless paper pushed through my door.

This paper is invariably immediately binned and stored in a box in the garage prior to being carted off for recycling. Now, call me cynical but I’m pretty sure some of the recycled paper ends up going to our local Urban Waste Renewal centre (aka incinerator).

This paper will, of course, burn nicely yet rather too quickly to derive useful heat. That is, until you compress it into useful ‘logs’ or ‘bricks’. It just so happens that there are already paper-fuel-log presses on the market! The first type relies on you soaking all your paper and turning it into a sort of mulch before putting it in the press and squeezing it down. The second type uses torn-up paper, pressed down and bound by a sheet of newspaper. Obviously, the ‘wet’ kind is rather laborious but probably produces more compressed and therefore slower burning logs whereas the ‘dry’ method logs would perhaps burn a little less efficiently.

The wet log maker available for purchase seems to have a somewhat compromised design which is intended to fit into retail packaging rather than offer the best leverage. It could be possible to modify or even scratch-build a press with longer levers to reduce the necessary effort when pressing the logs. Anecdotal tales of logs made with this system suggest the will burn for one to two hours so you may need rather more paper than you would straight-forward wooden logs.

Of course, it’s not just the junk that gets delivered directly to your door that you can burn, there are plenty of other sources of fuel which would otherwise be thrown out or ‘recycled’. For a start, I defy you to find a microwave meal that doesn’t come with some sort of cardboard packaging, even bottle of beer are sometimes bound in cardboard. Then there’s your newspaper. Reportedly 1 newspaper will produce one log or brick so if you have a paper every day, that’s six to seven logs a week for a start. Then there’s all your old bank statements and personal information which you wouldn’t want falling into the wrong hands. If you have a suitable supplier (a wood shop or even a DIY mad friend) you can also augment your fuel with wood shavings.

My personal recommendation is that you do not burn these logs on an open fire. There’s the potential for the printing inks to produce somewhat noxious fumes and the same goes for vinylised/plasticised papers. A better idea would be one of those smart-looking solid-fuel fireplace stoves which have a flue going directly up the chimney. These stoves have a vent control on the front to help regulate the burning of materials.

Your average 1930s semi will probably have a good sized fireplace. Unfortunately, with the vagaries of ‘property-shows’ on TV, it’s probably been bricked up (or just hidden behind MDF). Still if you can dig it out you’ve got a means to heat your home. You’ll want to get a chimney sweep in before you fire it as extant creosote deposits on the inside of the chimney have the potential to ignite causing a chimney-fire which is dangerous to say the least.

I estimate that the average UK family home will be receiving sufficient fuel for two to three fires a week. Just think, that’s two to three days that you can at least partially heat your home for free*

*You do, of course, have to put in a bit of effort to make your logs but it should be good excercise

Venerable ‘Aunty’ BBC in it’s unerring quest to write-off the sciences in this country has a new article in it’s ‘magazine’ section entitled: “How to build your own Sputnik”.

Now, you might expect a bit of practical information here about how the original Sputnik-1, launch in 1957, was actually constructed and what sort of design considerations would be necessary to ensure your “DIY Sputnik” does not fail…

…unfortunately not.

The BBC article roundly suggests that a DIY Sputnik could be constructed from ‘off the shelf, retail components. The DIY Sputnik of the BBC article is housed in a “biscuit tin” (with foil!) and consists of a Tomy* Baby Monitor, a Mercury Thermometer, 4x large batteries, a party balloon, a backup “power pack”, a domestic thermostat and a battery powered fan.

*Quite why Tomy is the brand recommended by the BBC for this design is something I’m yet to discover.

Now, I can understand why you’d want the batteries, thermometer, thermostat and fan. The batteries are quoted as being ‘large’. You do not want your batteries to be large. You want them to have a good lifetime but you do not want them to be any bigger than absolutely necessary. It is also suggested in the article that your Sputnik should carry a ‘backup’ power pack. I’d suggest that this is unnecessary mass; whatever causes your primary power cells to fail would probably also cause your backup cells to fail in this sort of mission - probably explosive decompression or overheating but I’ll get on to that later too.

The thermometer seems like a good idea, you would want to monitor the temperature inside the biscuit tin. However, the BBC article suggests a mercury thermometer which could be a little hard to read when your Sputnik is way up there and you are down here. Perhaps a simple thermocouple, the most common form of electronic temperature sensing, would be a better idea?

Then there’s the thermostat (for turning the battery operted fan on no less). The BBC article stipulates a ‘Domestic thermostat’. Isn’t this rather eccentric considering that most domestic thermostats require mains voltage and the fan it would be switching would be a low powered DC affair? You’d need an inverter just to power the thermostat.

The fan itself is a relatively good idea, Sputnik 1 had one and it serves the purpose of moving heat around the casing to avoid excessive localised heating and providing some thermal management of the electronics suite. You’d wan’t to be rather careful on the size, mass, type and fitting of your fan tho. When your fan spins up (controlled by your thermostat) it will impart spin on your whole sputnik. This may make correct orientation rather tricky.

There is a wireless access point included in the inventory. I’m at a bit of a loss as to why it is here, there are no computers on board and it’s unlikely anyone will be ‘wardriving’ in LEO.

Now we come to the curious inclusion of a party balloon and a baby monitor (Tomy is best I am told). The article explains that the balloon, if slightly inflated before launch could be used as a ‘pressure sensor’.

A party balloon can act as a simple pressure switch of sorts - a partially inflated one would certainly expand and burst if the pressure outside dropped to zero

Sure it can! That’s why you wanted Tomy’s finest on board isn’t it? So you could hear the balloon pop! Only that wouldn’t work, would it? Anyone who was awake during their school physics lessons should be able to tell you that if the pressure was zero your baby monitor wouldn’t hear a thing as no sound can travel in a vacuum.

We’ll give the author the benefit of the doubt here though and assume the balloon ruptures prior to the pressure reaching near-vacuum so at least a small sound reaches the baby monitor.

It still doesn’t work. As the pressure dropped, some small components in your Baby monitor known as capacitors will have been expanding, rupturing and distorting leading to its demise. If that doesn’t stop it working, you could be pretty certain that the consumer power cells you obtained ‘off the shelf’ will have already ruptured and stopped providing power. Most people would just fit a barometric switch (just like Sputnik 1!)

But that’s all a bit beside the point. This thing is housed in a biscuit tin (according to the helpful BBC diagram). Now while many containers have been designed to withstand a vacuum, biscuit tins are not one of them.

Sputnik 1 was constructed within two metal hemispheres, hermetically sealed together with 0-rings and a bolted flange. It was designed from the ground up as a pressure vessel in it’s simplest fashion.

Even if you could somehow seal the lid of a biscuit tin up properly, the whole thing would explode the moment it was exposed to a vacuum as it just doesn’t have anywhere near the structural integrity required to sustain the difference of 1 atmosphere.

The casing of the real Sputnik was also designed to withstand the extensive heating of the sun. Don’t forget, your satellite will be exposed directly to the sun for more than half of the time it is up there (the higher the altitude, the greater the duration of exposure per orbit). The article intimates that this sort of casing may prove hard to come by but helpfully suggests using ‘foil’.

The real Sputnik used a polished 1mm thick layer of aluminum-magnesium-titanium. Perhaps just a little out of the price range of the average ‘Blue Peter’ creation (unless they have another phone-in)

The article rambles on about how LEO is littered with ’space debris’;

Without the ability to manoeuvre around these space hazards, it’s very likely that sooner or later your home-made satellite will hurtle into a piece of this rubbish and be obliterated.

It’s not quite that crowded up there you know. Your [inert, depressurised]biscuit-tin Sputnik will be a small device and as such present a very small surface for collision. Vehicles such as the Space Shuttle and ISS are pretty big and are actively moved away from larger pieces of space debris and designed to withstand hits from very small ones. They, of course, present a large surface area and are many more times more likely to conflict with debris.

What’s really going to kill your ‘DIY Sputnik’ (other than the general stupidity of its design) will be re-entry. At the 134 mile periapsis of the original Sputnik 1, your biscuit-tin-in-the-sky will be experiencing the drag of the upper-atmosphere. This will gradually and inexorably reduce the orbit until the buiscuit tin, baby monitor and all, burn up due to the frictional heating of the atmosphere.

At this point I’m thinking this is just a sort of excercise for the reader (or the reader’s kids) to undertake and place down the garden on a simulated ‘mission’ but no…

Do you fancy building you own Sputnik? We’ve given you an idea how easy it could be, now the Magazine wants to hear from willing volunteers. We can even come and film you putting it together. We’ll also investigate how to get your Sputniks launched.

This is something you should really consider before opening your mouth. As a back-of-the-envelope calculation, I reckon, to launch Sputnik again (83.6kg) to LEO using a dirt-cheap Zenit launch would cost in the region of £160,000 if bundled up with other paying payloads.

Do they really intend to burn the license-fee payers money firing buiscuit-tins into LEO?

I’m of the opinion that the article’s suggestion that a satellite can be built with commodity components of this level and with no apparent engineering skill is nothing short of fantasy. The ‘bad science’ (or complete lack of science) thrown in for good measure is insulting.

Satellites, at the very least, remain outside the grasp of the general-public’s purse and engineering capabilities. The expertise and funding still required to produce even a minimally functional satellite remain the preserve of academic institutions, corporations and governments.

The original BBC article can be found here