We were promised magnificent flying cars

We were promised magnificent flying cars

I know I promised irradiated feet, but I couldn’t pass up the Edsel of flying cars. Take a moment to appreciate the breathtaking fins on this:

Sketch from the Einarsson Flying Car patent showing front and side as a car

Einarsson Flying Car patent

Every time I look at the drawing, I think it needs to be a deep cherry red with chrome so bright you need sunglasses to withstand the glare. Sarcasm aside, this design is very much a product of the times. Designed in the late ‘50s and patented in 1963, the Einarsson Flying Car has an admirable meshing of luxury car with the sleekness of a James Bond getaway vehicle. Oh, and those fins!

The dream of turning a car into an airplane goes back to at least the 1930s.  I remember the “future of tomorrow” films of the 60s that had us zipping around with our own personal jetpacks and Jetson-like flying cars by the turn of the century. The future was so full of yet to be conquered technological wonders that would make our lives easier. Instead of flying cars in every driveway, we ended up with Twitter in every pocket. The disappointment is crushing.


A few actual working flying car prototypes have made if off the drawing board. The most notable being the 6 designs build by (Molt) Taylor Aerocar in the late 40s and 50s. One was still flying as late as 2008 and there’s a website devoted to people hoping to buy one. They look like traditional 2-seater aircraft with larger, road ready wheels, except for the Taylor III, which resembles a Franken-mini. Looking at Taylors got me thinking about other attempts, which in turn led me to one Einar Einarsson and his patent for a Flying Car.

Patent 3,090,581
May 21, 1963
Filed Aug 12 1959
Inventor: Einarsson Einar

A vehicle capable of cruising on land and in the air comprising a body, a plurality of wheels mounted under the body to support the vehicle while on the ground, means for supplying power to the wheels for cruising on the ground, front and rear propellers mounted on the body to provide for take-off and cruising power when in the air, and a pair of pivotally mounted wings secured on the body and being adjustable as to the angles to the horizontal for take-off and cruising positions for the wings, said propellers being connected to receive power from the power supplying means and the wings forming a wing extending from the front propeller to the rear propeller with a bridging element to receive the pressure between the propellers

Einarsson’ s design borrows heavily on the Aerocar idea, with a number of alterations that shows a bit of forward thinking. Looking through the cited patents in Einarsson’s filings, I find it curious there are no references to Molt Taylor’s patents. However, I’m neither a lawyer nor an engineer and my knowledge of both is just enough to show how much I don’t know.

A sedan with wings

Unlike almost every flying car design I looked at, Einarsson seemed to envision a luxury sedan with wings, rather than a compact, economical model. It would be the ultimate marriage of the sleek 1950s tail fin stylings with a private aircraft.

Sketch from the Einarsson Flying Car patent showing front and side with propellors showing

Einarsson Flying Car patent showing front and side with propellers

The Taylor flying car relied on a push propeller. For those in the audience who aren’t aviation fans, let’s take a quick break to explain. The rest can skip down a few paragraphs. Aircraft today (excluding jets) generally have the propeller on the front of the plane – either on the wings or the nose. This is referred to as a pull propeller because it pulls the airplane forward. Although this is considered the traditional form, the earliest aeroplanes used a push propeller. Here are two famous examples:

Here’s a Farman biplane

Scan of a postcard showing a Farman biplane in flight

And one of my favourites, Alexander Graham Bell’s Silver Dart:

Photo of the Silver Dart biplane in flight

The Silver Dart

Sketch from the Einarsson Flying Car patent showing front and side with propellers showing

Front and side with propellers

See the difference with modern airplanes? The propeller is seated to the back (behind the pilot) and pushes the airplane forward. Many pioneer aeroplanes used this style and, if you poke around google a bit, you can find a couple modern planes that use it as well, though it’s not very common.
The Einarsson Flying Car proposed using both the push and pull propellers in what is called a push-pull configuration. This has some benefits re: drag and stability if one engine dies but it also greatly decreases fuel efficiency.

The hood and trunk pop open so propellers can slide out and be affixed front and back.  “A further object of the invention resides in a flying car with front and rear propellers of which the front propeller is of the pulling type and the rear propeller is of the pusher type”.

The added weight along with 2 engines capable of creating enough lift stirs up a few questions. Looking at one of my favourite pioneer planes – the Antoinette Flyer (1906), the V8 engine in that wood and cloth aeroplane weights 209 lbs alone. I wonder how large an engine would need to be to lift a large, steel, 2 propeller car with wings, carrying both driver and passengers. Modern aircraft have the advantage of lightweight materials to help with the tricky weight problem. They also benefit from modern micro circuitry that creates efficient instrument panels. Neither of which were available in the early 60s. The Einarsson Flying Car would be the original heavy metal behemoth. The patent makes no mention of instrumentation and glosses over engines, two crucial components. Perhaps Einarsson was more interested in basic over-all design at this stage.

 … each car may have a common plant to drive both the ground wheels as well as propellers with suitable clutch devices to control one or the other cruising power. Separate power plants may be used for air travel jet engines may also be used with and without the use of propellers.

There wasn’t a hope in hell a jet engine was going to be affixed to the car. Imagine the havoc caused on roads when someone kicked on the engine. The backwash alone would be a public hazard. One also has to wonder what the noise level would be inside the car with both engines running whether jet or regular.  

Getting back to the patent, Einarsson envisioned foldable wings, although this is also frustratingly vague. The best I can figure is they would fold flat against the body when not used. This wasn’t going to be a one touch convertible model. To use the wings, the driver would have to pull them out and affix them, which sounds a bit like an arm strong application – better have a strong set of arms to put them in place. I’ll leave you to read about the wings and let me know how you think they’ll work.

Sketch from the Einarsson Flying Car patent showing side view

Move over Jetsons

The sheer weight alone would make this one expensive vehicle to run. Which led me down another rabbit hole or two of conjecture – what about fuel. The basic car would run on regular gas, but the air and jet options would require special fuel. Without easy access jet fuel, the lack of infrastructure doomed that part of the design, not to mention proper pilot training to run a jet-propelled aircraft. I also wondered how much space the vehicle would need for takeoff. This isn’t a compact little Taylor Aerocar. As I wrote earlier, this would be a behemoth of steel, chrome, and engines. I wonder what the overall weight would be. I have about 20 other questions but, I’ll save them for another discussion because I can see another couple of patent articles in the making.

So where now with the promise of flying cars?

Though most entrepreneurs like Elon Musk have abandoned the idea as impractical, there are companies currently building working prototypes. Look at the heart stopping lines on this beauty:

Photo of the new Aeromobile flying car https://www.aeromobil.com

Aeromobile flying car https://www.aeromobil.com

It’s from Aeromobile in Slovakia and boasts a vertical takeoff, a parachute system embedded, lightweight materials, stowable wings much more.  To me these vehicles are as exciting as early pioneer airplanes like the Bleriot, Silver Dart and Antoinettes. My interest in aircraft pretty much ends with the advent of metal frames. Biplanes, especially pioneer aircraft, get my heart racing in a way very little else does. But modern flying car designs seem to be triggering the same effect on my pulse, so I’ve been deep diving into flying car patents, having fun looking at the ideas pushing them forward. And yea, I’d go for a fly in one in a heartbeat. Hand me the waiver, strap me in and let’s go!

Read more: 

  1. EINARSSON FLYING CAR patent US3090581A https://patents.google.com/patent/US3090581A/en
  2. Taylor Aerocar https://www.tayloraerocar.com/ and https://en.wikipedia.org/wiki/Molt_Taylor for information on the brilliant mind behind it.
  3. Molt Taylor is one of those wildly underappreciated pioneers and I highly recommend you spend time googling his name.
  4. This is my absolute favourite airplane Antoinette Flyer: https://en.wikipedia.org/wiki/Antoinette_IV
  5. Silver Dart: http://airforcemuseum.ca/en/aircraft-2/silver-dart/aea-and-the-silver-dart
  6. Farman Aviation: https://en.wikipedia.org/wiki/Farman_Aviation_Works
  7. Aeromobile: https://www.aeromobil.com/aeromobil-4_0/
Where the hell are the patents?

Where the hell are the patents?

I’m working on a number of new articles for the patents section. It just takes so dreadfully long to do the research and pull them together. Well, not almost a year long. That’s a 50/50 combination of too busy and too lazy to do extracurricular work. I have a backlog of about 50 patents in my archives I’ve been sifting through, and these are the ones I’m focusing on:

1938 shoe fitting machine patent – complete with a dose of radiation

Patent for foot flouroscope - how about a dose of radiation with that shoe fit?Alexander Graham Bell’s 1902 patent for his aerial kite

Page from Alexander Graham Bell's 1902 aerial kite

An 1892 submarine patent

Page from an 1897 submarne patent

Fitted sheets – because who doesn’t like a patent for a torture device

Page from patent for fitted sheets

The Bell patent is going to take a lot more research, so it is an unlikely candidate. It may be the fitted sheets because the entire contraption is so over complicated and vicious looking, I can’t resist.  If you have a preference, drop a line in the comments section. I’ve had to layer on quite a bit of spam protection so you’ll have jump through a few spam prevention hoops, but I do enjoy hearing from people. If you have an idea for me to explore, I’d be thrilled to hear it.


The unmitigated terror of lawn darts – why they were banned

The unmitigated terror of lawn darts – why they were banned

Are you old enough to remember being terrified of being skewered by lawn darts? You know, those metal pointed, weighted darts that look like miniature javelins with fins? In any other dimension, they’d be treated as a weapon, not a game for children. I’m periodically stuck on the subway with nothing to do but let my brain wander through a tangled landscape of ideas and half written articles and during an epic delay underground recently, I began thinking about lawn darts and wondered why I no longer saw them.

Photo of an old Hasbro Javelin Lawn Darts set

Everything is fun and games until you get a lawn dart in the head

Scan from 1970 Hasbro Lawn Dart Patent

Drawing from the 1970s patent for lawn darts

Nightmare memories of lawn darts

We had a neighbour, years ago, who owned a set, decades ago, and I hated them… the darts, not the neighbours. Their kids where a bit cavalier about launching them into the air and woe to anyone who got in their way. The metal tipped missiles created havoc when they went astray.  I looked for the original lawn dart patent from sometime in the 1950s but had no luck. I managed to dig up an old Hasbro patent application from 1970 that reworked the design a bit.

The pointy bit was still made of a heavy metallic material (usually lead) so it would hit the ground with sufficient force and not wobble about. The new bit was a proposal to use molded plastic for the fins and shaft to cheapen the costs per unit.

“Referring now to the drawings, there is shown generally at 10 a dart construction comprising a weighted head portion 12, a metallic shaft 14 extending from one end thereof and terminating in point 16, an elongated plastic shaft 18 extending from the opposite end of head portion 12, and a tubular portion 20 having vanes 22 extending integrally there from.” 1

Drawing from Irwin Toy's lawn dart patent 1975 - details on how they are constructed

Details from Irwin toy’s lawn dart patent

Irwin also manufactured a popular series.

I couldn’t find the original patent but did find one from 19762. It looks equally deadly:

In hindsight, it should never have been a game marketed to kids. Then again, my neighbours shouldn’t have left the darts unattended, but that was the 60s – survival of the fleetest of foot.  The concept of lawn darts is a fun one … the delivery, not so much if you get nailed by one, which prompted me to see if anyone has produced a solution to their deadliness. The trick, I suspect, is the darts must have several features to be effective, including sufficient weight and a pointy end that sticks into the ground, which is what makes them such efficient weapons. Without a tip, proper weight distribution and fin length, you end up having a sad game of “toss the metal tube about and hope it eventually sticks into the ground”.

The metal tipped version was outright banned in Canada in 1989.  Why? According to tests, lawn darts could exert 23,000 pounds of pressure psi – enough to crack through a human skull and puncture the brain. Which it did. In less than a 10-year span, over 6,000 people made trips to the emergency room for treatment – 80% were under 15 years old and 50% under 10.  The injuries included “punctures, lacerations and fractures to the head and skull”3, along with eye injuries, usually to bystanders.

“The combined factors of weight, the narrow-elongated shaft, the speed that the dart is traveling at the time of impact, and the thickness of the child’s skull at the point of impact present the risk.” Consumer Product Safety Commission3

In the US the darts were eventually banned, unbanned, and then banned again [see articles below for the full, tragic story].  It’s a bit complicated. Currently, there is a brisk trade in used sets. Just scan Kijiji or Craig’s list in the summer and you’ll see people begging to find a set to buy. I spotted one person offering over $200 for a set.  I was a bit surprised by this, especially given their ability to maim. Nostalgia overrides safety sometimes.

Safe lawn darts

As it turns out, a few people filed patents for safe lawn darts. Most didn’t make it off the drawing board. Many of the patents focused on using a blunt tip. It’s a decent idea, but the darts don’t always stick into the dirt, in as much as they plop to the ground and bounce about a bit. Given enough height, they will penetrate the ground, but then we’re back to the same issue – weight, height and skulls don’t mix. Others tried a combination of lighter non-metal darts with blunt tips or flat bottoms rather than tips. Again, people complained about lack of control when the darts were thrown. The thing about traditional lawn darts is they stayed where they dropped, making it easier to score.

Photo of Coleman's Lawn Dart sets - modern safety "darts"

Safety lawn darts from Coleman

Most modern versions of lawn darts have settled on a uniform design:

Coleman’s is typical – blunt, flat bottomed, soft end to prevent skull damaged and weighted to help with stability. Poof makes a set that looks a bit more like a traditional lawn dart, and using the Jarts brand name, but with a round plastic ends rather than metal. Far safer, but many people complained they couldn’t stand up to a lot of impacts and fell apart.

photo of Poof companies safety Jarts

Jarts – safe lawn darts

The biggest issue is the newer lawn darts bounce about too much making it hard to score. Most complaints appear to come from people who played the original lawn dart games and lament the lack of accuracy and control the old javelin styled darts had. Issues seem to revolve around whether the ground is too hard and dry, or the grass is too long. Either cause serious bounceage (not a word, I know). I suppose you could hose down the backyard before playing but that brings a new set of problems to the game. Without the traditional javelin point, bounce will continue to be an issue. But seriously, it’s a backyard game not the Olympics.

I have an idea that might work. Get a large cloth made of Velcro, cut it into squares with numbers and scatter them around the yard. They need to be largish swaths of material or the game won’t work.  Then Velcro tip flat bottomed darts. The darts should come in varying weights for different types of throwers, like real darts. Space out the cloths and then when you throw, the darts stick. Miss the cloth? Oh, it’s like falling off the dart board, no score.  I like Velcro – it can solve so many of life’s little problems.


Read more:






  1. Original Patent https://www.google.com/patents/US3672678?dq=inassignee:%22Hasbro+Industries,+Inc.%22&hl=en&sa=X&ved=0ahUKEwj04eSevKfVAhUi5YMKHchxCfw4ChDoAQh     kMAk
  2. Irwing Out Door Darts Patent https://patents.google.com/patent/US3982762A/en?q=lawn+dart&assignee=Irwin
  3. Consumer Product Safety Commission https://www.gpo.gov/fdsys/pkg/CFR-2015-title16-vol2/pdf/CFR-2015-title16-vol2-part1306.pdf
You knew I’d get around to litter boxes eventually

You knew I’d get around to litter boxes eventually

You just knew I was going to get around to litter boxes eventually, didn’t you? It was inevitable I’d start poking around patent archives to see what was out there. Colour me surprised – there are a LOT of patents for various cat litterbox designs. Everything from fully collapsible to pretty little houses for the fussy cat owner. It’s impressive how much brain power has gone into the basic concept of a litterbox.

After filtering through them, I settled on the earliest patent I could find. I present the 1939 Kramer self-flushing animal toilet, patent #US2204416A, filed 1939-04-13 granted 1940-06-11

Image from patent for the Kramer self flushing animal toilet

Sheridan H. Kramer, of St. Paul, Minn envisioned a litter box that attached to the building’s plumbing, was portable and could act as sleeping quarters for either a cat or small dog. Kramer had apartment dwellers in mind, hoping such a device would convince landlords to allow pets because the issue of sanitation would be addressed.

The design is interesting. The cat enters through a doorway into compartment A, which is designated as a sleeping area. Compartment B, the toilet tray, is accessed via a small opening from A. When the cat walks from B back to A, a small lever on the doorway floor is tripped by the cat’s weight and flushes the toilet.

Compartment B has a water tank that hooks into the apartment’s plumbing. The tray connects to the building’s sewage outtake for quick disposal. Figure 3 (image below) shows how the door lever is connected to the tank. The animal’s weight triggers the lever, which is attached to the tank handle. Water fills the tray and drains away through a series of holes under the tank (hard to see, but look for 26A in the image). The tray itself is on an incline so the water will flow towards the holes. When the cat steps off the door lever, the handle pops back into the up position and the water stops flowing. The tank will fill itself again and the tray will drain.

Image showing interior of Kramer animal toilet

If you look at figure 1, the one with the door, you’ll see a bunch of holes in the front panel. Those are air vents. The front door closes, in case you want to keep the cat or dog in one place.

On one level, it’s brilliant. No cleaning required. On another, not so practical. Installation would require permission from the landlord, which I doubt would be forthcoming. I tried to figure out a simple way of doing it, but nothing short of having a plumber come and refit a couple of pipes would work. It’s not like there’s are in/out pipes hanging around ready to be plugged into, especially at floor level. Not many landlords would be keen on this expense. Kramer did design this with portability in mind so you could hand fill the water tank, but that would quickly turn into a pain. And you’re still faced with flushing – where would water and feces go. As far as portability goes, this box would be heavy and not what I’d consider portable.

The other primary issue centres around the fact cats can be real assholes. Sure they like to crawl into small places, but have you ever tried forcing a cat to get into a small carrier? Battle armour and bazookas are the order of the day. Training a cat to use the tray could be a nightmare. Kramer admits in the patent, the animal may have to be locked into the box to force it to use the toilet tray. Some cats might train to use it, but most? Not a hope it’s going to happen.

Another issue comes to mind. Cats don’t like surprises. The flushing would send many cats into a frenzy to get away, especially if they are half way through the door and the water comes flooding in and soaks their paws. If you have the door shut, the cat would go into full panic mode and quite possibly never enter the box again. Think I’m exaggerating? Just cruise Youtube for videos of cats shocked by cucumbers on the floor (and please don’t do this to your cat, it’s cruel and rather stupid). They don’t do well with shock and awe tactics if they are the target.

If you manage to train your cat to use the box, you might find your water bill going through the roof. Imagine coming home to find out your furry friend decided to sleep on the door lever. Or they ignore compartment B and use A as their toilet.

Too many impracticalities likely killed the idea.


“Drive like lightening”, the Robertson Screw

“Drive like lightening”, the Robertson Screw

How’s this for a piece of cool technology, the Robertson Screw?

Image of a Robertson screw courtesy By User:Saforrest - Taken by User:Saforrest on 9 October 2007, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2888264

Behold – the Robertson Screw

How many of us have cursed the traditional flathead screwdriver- usually that nanosecond you feel it slip in the groove and you know you’re about to suffer a disgustingly, ugly hand wound. Or cursed the Philips screw because the little star shape became damaged when the driver slipped.  There have been many attempts at improving the basic screw and my favourite is a Canadian innovation.

Development of the Robertson screw

Image of P. L. Robertson's patent illustration of Robertson Screw @1908

Patent illustration of Robertson Screw @1908Why is this a great example of tech at work? The design improves on an old idea – slip a screwdriver into the snug little square head and you can get an amazing amount of power behind it. Well, plus, for people like me who are a menace around power tools of all sorts, you never run the risk of the drill winging off creating embarrassing divots along the woodwork. There is a reason I don’t do home repairs.  But I’ll leave that for another tale.

Photo of P. L. Robertson, inventor of Robertson screw

P. L. Robertson, inventor of Robertson screw

Peter Lymburner Robertson is one of those underappreciated Canadian inventors who built a small empire a one small screw. Although many are familiar with the square head screw (commonly referred to as a Robertson), few associate it with the man who invented it. That’s him over at the side. Robertson was living in Hamilton, Ontario and worked as a travelling salesman for a Philadelphia tool company.  He often related a tale of how and why he invented the square screw. Robertson was demonstrating a spring loaded screwdriver in the summer of 1907 (the date varies between 1906 and 1907, depending on which source you look at) when it slipped and he received a bad slice on his hand. After that, he began designing a slip-less screwdriver. Withing a year, he had a satisfactory design and filed for a patent in Canada. By 1912, he held the patent internationally.

The simplicity in the design is awe inspiring:

This invention relates to screws, the heads of which have axial driving recesses or cavities instead of transverse slots punched therein and the invention consists in a recess or cavity extending into the screw head, the outer portion of the recess or cavity being prismatic and the inner portion thereof being pyramidal, the apex of the pyramid being in the axial line of the prism and of the screw. (from patent papers)

In short, the screw slot is square and punched deep into the screw head rather than a slot running the length of the screw. What makes this screw so much better than a slotted one?  Plop the screwdriver into the recessed square and it’s gripped tightly with nowhere really to slip off. You can start turning with no fear of it popping out. As well, the grip is so solid, you can put a lot of force behind each turn of the screw. The square shape also makes for a much hardier screw and more difficult to strip. As well, because the screwdriver fits so snugly into the square head, it’s possible to drill the screw with one hand, adding to its overall utility. 

Ad for the Robertson Screw

Robertson Screw ad

This was an important innovation, especially with industries looking to save time and money – a screw that could be inserted faster saved big dollars. It’s a bit hard to believe, but consider this, fewer slips of the screwdriver meant less damage to the item being manufactured. A win, win situation.

Robertson screw fails to gain a foothold

After WW1, the Ford Motor Co initially used the Robertson on its Model T and A cars. By using the Robertson, Ford said his company could save an average 2 hrs assembly time on each vehicle. This presented a massive advantage in both savings and getting cars to market faster. The deal to use the Robertson fell apart when Ford wanted P.L. Robertson to sign an agreement that would allow Ford to make and hold all distribution rights for the huge US market. Robertson was averse to signing a deal that potentially meant he would lose control over his invention.  Robertson refused to turn any rights over and unfortunately, when no monopoly was forthcoming, Ford switched over to the Philips screw. Philips was more than happy to hand over the rights.  In an odd twist of fate, this failed deal meant the Robertson never really took hold in the US, but it’s ubiquitous here in Canada. I doubt there are many toolboxes that don’t have a few Robertson screw drivers rolling around inside.

Read more:

Archives Canada – Robertson Screw and Screwdriver
You can download the patent here: https://patents.google.com/patent/US975285A/en?q=screw,roberston&inventor=Peter+Robertson&before=19100101
Robertson Fastener website has a bit of info as well