Warflying with Kismet

[argh]

fun with warflying. i only had about 30 minutes to make a quick loop with it, and we were traveling pretty fast for a single antenna with an 8 degree slice of beamwidth.

don't try this with anything that transmits!

me: WOW, THOSE PEOPLE LOOK LIKE ANTS!
pilot: those are ants, we haven't taken off yet.

[mark571]

Very nice . Hmmm, what are the odds . . . . ? Is it possible that '68 Cessna is an ex-pipeline patrol plane with a pilot named Terry?

[argh]

I don't know about the plane. It's now a rental from Tulsa, rented by Mark.

[mark571]

I asked because I have a high school friend in Tulsa with a '68 Cessna 172 with in-laws in MO. <grin>

[argh]

I believe the plane is a 172. Mark is a flight instructor somewhere there in Tulsa.

[poacher]

Just curious as I was thinking about various modes of transport for war driving the other day and I was wondering as to what altitude you have to fly at to log networks from an aircraft? i.e. are you skimming roof tops?

[littledave]

Just curious as I was thinking about various modes of transport for war driving the other day and I was wondering as to what altitude you have to fly at to log networks from an aircraft? i.e. are you skimming roof tops?

Take a look @ the pictures that he posted. Your answer lies there.

[poacher]

Ha! Missed that link, thanks.

[argh]

it's a tradeoff, on altitude vs. speed. since we are farther away than 'normal' range, you want as high gain of an antenna as possible. this makes a smaller and smaller 'cone of influence'. the one i was using's window is about 8 degrees by 10 degrees. the lower you are closer you are, and potentially the more you will get. your antenna's footprint will be larger if you are higher, but then they are weaker, etc.

it takes several seconds to scan through the 11 USA channels, and going 100+ mph means that you are missing a lot of them just from going fast.

i read about Australian warflyers in 2004, and they were flying so slow the stall horns were going off and they weren't too far from just falling out of the sky! a more ideal setup would be a sector antenna mounted on the bottom of the plane, they typically have a 120 degree pattern (but not as much gain).

i am not a pilot, but in USA i think you are supposed to be above 1,000 feet in populated areas, and 500 feet in rural areas. every tower 200 feet or higher is required to have a light on it.

low and slow would be best, and criss-crossing an area will give better results. i have a friend that just got a hot-air balloon, i volunteered for navigation and maps. hmmmm.

[argh]

bump.. well, two years later, I got go to warflying again. Same pilot, a slighly newer Cessna 172 (this one was a 1971) and a smaller antenna. The first trip I used a parabolic antenna handheld (only do this with Kismet, because it does not transmit). This trip I used a little 5.5 DB magmount. The parabolic obviously had lots more gain, and from the maps in the link in the first post you can see that it's clearly only getting them out the side that I pointed it, at the expense of the other side.

The little magmount actually worked well, and was certainly easier. The first trip I held laptop, antenna, and GPS all in my lap. This trip I was in the back seat (s), and had room to lay the laptop in the other seat.

This is all still a very rural area, and we basically flew over three other small towns. I got 15,000 total APS in two hours. I had driven some of these areas quite a bit, I wound up with 3220 new ones.

Fun stuff, highly recommended. We burned 12 gallons of fuel. If you have a friend with a plane, get some people to chip in for gas. Pics forthcoming.

[littledave]

bump.. well, two years later, I got go to warflying again. Same pilot, a slighly newer Cessna 172 (this one was a 1971) and a smaller antenna. The first trip I used a parabolic antenna handheld (only do this with Kismet, because it does not transmit). This trip I used a little 5.5 DB magmount. The parabolic obviously had lots more gain, and from the maps in the link in the first post you can see that it's clearly only getting them out the side that I pointed it, at the expense of the other side.

The little magmount actually worked well, and was certainly easier. The first trip I held laptop, antenna, and GPS all in my lap. This trip I was in the back seat (s), and had room to lay the laptop in the other seat.

This is all still a very rural area, and we basically flew over three other small towns. I got 15,000 total APS in two hours. I had driven some of these areas quite a bit, I wound up with 3220 new ones.

Fun stuff, highly recommended. We burned 12 gallons of fuel. If you have a friend with a plane, get some people to chip in for gas. Pics forthcoming.

So the antenna was mounted were? It makes me wonder if I could do or dare the same on a commercial jet? Take off and landing, would give me some aps I never have a chance of getting. Still waiting the pictures

[argh]

Original pics are in the first sentence of the first post, I still am waiting for pics of the last fly from the pilot. There's not many pics of gear this time. Antennas were handheld both times, second time was much more convenient. Don't do this with Netstumbler, it transmits.

The first time I held the larger antenna in my lap, along with laptop. Very crowded. A 5.5 db magmount antenna is quite small, I just propped it up by a window. I was using the kind that has it's own ground plane below the whip, the whole thing still wasn't five inches across.

You might have some explaining to do, getting the antenna on board in your carryon, just because it looks weird and technical. if a stewardess saw it out, she might freak out (OMG IT'S TEH TERRORISTS).

The parabolic would be out of the question for an airliner, I think. Takeoff and landing might be all you get, because we were buzzing along at a couple of thousand feet, they cruise at much higher altitude than we were.

Most aircraft have a lot of aluminum in them, which is still a pretty good RF shield, it wouldn't work so well without a gain antenna of some sort.

Here is a crappy cellphone pic of the screen:




The fuzzy blue line shows us looping once around a town. Yes, I know 166 mph is no big deal for a plane, but as a landlubber, it's cool. Again, I am missing more than I am getting by going that fast. With only one card and antenna, Kismet has to cycle through all the channels, it takes a few seconds. At 166 mph, I have already gone past many of them before it comes around again. Here's the plane on the ground:

[icurnet]

fun with warflying. i only had about 30 minutes to make a quick loop with it, and we were traveling pretty fast for a single antenna with an 8 degree slice of beamwidth.

don't try this with anything that transmits!

me: WOW, THOSE PEOPLE LOOK LIKE ANTS!
pilot: those are ants, we haven't taken off yet.

That might have worked better if your hand was not blocking a good portion of the antenna!

[argh]

That might have worked better if your hand was not blocking a good portion of the antenna!

You are incorrect, sir. The actual antenna is a dipole at the end of the stick. Fleshy material in the path of the reflector is a small percentage. It does not block the focal point but a tiny bit.

[Chairboy]

Some friends and I went warflying a couple years ago in my Cherokee. We had problems attaching the yagi we had planned and ended up just holding an antenna up to the window. We picked up lots of APs, but it was too hot or miss and the GPS data was worthless because it was omnidirectional @ altitude.

I'm just getting back into this, so I might take a spare cantenna and tape it facing directly downwards from the belly of the plane so I can have somewhat accurate numbers. Racetrack patterns over my cities should get me some useful data.