Flyinglow

Ok, so ever since I saw First Person Video's from R/C airplanes online, I have wanted to join the fun. The cost has been quite prohibitive however. The ultimate setups are real time virtual reality setups complete with on board telemetry and GPS navigation.

I've looked into mounting video camera's on the plane, however, the camera's available to date have either been too heavy, too expensive or poor quality video (or all of the above).

Well, a few weeks ago I was introduced to a keychain camera that records 640x480 for less than $20!!! It arrived on Monday and wow. It's small, light and the video is actually quite reasonable. Before ordering your own, check out this extensive research page. The unit I received is apparently a #7 version. Here's my camera (for those outside of Canada, that's a one dollar coin - about 2.5cm across):



and here's my first FPV video taken from my golden yellow foamy:



Enjoy! There will more to come I'm sure!!

Summer is finally here. Temperatures in Winnipeg are getting up to 30C and with that, the air conditioners are powering up. I've been tracking my A/C usage along with my furnace since January 2010. I'm actually surprised how little electricity the air conditioner uses compared to the electric furnace. In fact, to make the daily & monthly graphs 'interesting', I've had to multiple the calculated power usage by 10.

Now, 30C is not that hot compared to other places in the world, and in Manitoba our power is reliable, plentiful and inexpensive. After returning from a business trip to Southern Ontario during a very hot spell (highs of 35C) I began to appreciate how the air conditioners are able to strain the grid.

In a conversation back home the question came up - can  an A/C unit be made more efficient by pouring water on the condenser coils outside? (We had been noticing water droplets coming off our office building during hot weather - and are assuming that the building is using water to cool the outside coils).

So, yesterday while the A/C was running at home I tried some experiments. The temperature was 27C outside, and because I have my thermostat cool the house down for night, the unit was going to run for a couple hours non-stop.

I measured the current draw on the compressor at 7.5A. This was my baseline. (And is what I have been using for my power usage graphs.)

Next I set up the garden hose and a hand held nozzle to direct a gentle mist or spray of water onto the condensing coils. I was thinking that a gentle mist would provide extra cooling by evaporating, and I also didn't want to create a flood beside my house from the water.

Back inside I took a few measurements of the current draw. I also timed how long 10 liters of water took to be sprayed onto the A/C unit. I wanted to compare any money saved by lower power with the extra cost of consuming water.

To my pleasant surprise, the current draw dropped by nearly 10%! After a few minutes of spraying water, the new reading was 6.85A (a drop of 0.65A).

10 liters of water was being used every 4 minutes and 12 seconds, or about 143 liters / hour.

Before pulling out the calculator, I did one last test. The coils outside pick up dust, seeds, etc and should be cleaned every year - I opened the nozzle up and gave the coils a good cleaning (600 liters / hour). The current dropped another 0.65A down to 6.2A!

Without a doubt, cooling the coils saves power. This is because the coolant condenses much easier when the coils are cooled down, the condensing lowers the pressure on the high side making the load on the compressor lower and hence the lower power consumption.

So, how much money do I save? Well, at $0.065 / kWh plus taxes, it works out to about $1.30 / month. Not much, but every dollar saved is one dollar earned, or something like that.

But while running water on the coils lowers power consumption and is good for the electrical grid, and lowers my power bill by a small amount - am I actually saving money?

Turns out, no. Water in Winnipeg costs $3.20 / 1000 liters. At 143 liters / hour, in one month (6 hours / day, 20 days / month), my water bill will increase by $54 - easily negating any electrical savings.

Anyway, for those who want to see the number crunching details, I've created a google spreadsheet where I ran the numbers.

Enjoy the summer!

So back in pre-2005 back when I lived on a large (75'x330') lot in a small town, a friend gave me a couple old .049 control line airplanes. With a bit of cleaning and tuning, I was able to get them running.

The first plane to come to life was a balsa wood with 'STUN MAN 23' stenciled on the wings. This bird was almost manageable for a complete amature like myself. It required some major repairs to get airborne as the fuselage was broken in 2. The fix was to insert a couple small finishing nails into the balsa wood (like a surgeon would pin a broken bone) and press the two halves together again. To make the joint permanent I then wrap thin layers of surgical gauze and epoxy around the joint.

Being a solo pilot with little to no help / assistance, I had to devise a way to launch this plane. The normal procedure is to stand in the middle of the circle while a partner fuels, primes, warms up the glow plus and spins the prop over (many, many times - the 049's were not the easiest to start), trim the mixture to max RPMs, wait for the pilot to be ready and then release the plane.

I had no such assistant. So I rigged a remote release system. I tied 10 inches of string with a loop on the end to the tail gear. I tied another 10 inch piece of string with a small loop on the end to a tent peg which was driven into the ground behind the plane. I then tied a long string to a 3 inch nail. The nail was fed through both loops and then gently into the ground. The string was run the middle of the circle along with the control lines.

I would then go through the starting ritual, get the engine running full out which would pull the strings taught. I could not go to the middle of the circle get the control lines ready and with a firm tug of the 'launch' string the plane would be released and flying!

22 laps (less then 2 minutes) later I would be so dizzy the headache would last for days.

A second plane that was in the set was a P-40. This one was all plastic, with a newer motor that started somewhat easier, however, flying this bird was not easy and often ended badly. Plastic though it was, it was a good thing I actually had 2 as the second plane donated a few parts to keep the first flying.

The challenge was finding a plane sturdy enough to learn to fly the hard way. The P-40 was tougher, but harder to fly and so it still broke. The Stunt man was gentler for flying, but balsa wood is too fragile for beginners. Thanks to the Internet a solution was to be found.