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Glom
2005-Mar-01, 05:38 PM
I want to be able to follow a bit of where we're going on the flight from Gatwick to Houston, at least for the first parts. I have a stopwatch for timing. I would like to get a compass, but they don't seem to be commonly sold. I thought I could use timed turns to determine the heading by assuming they maintain rate one in the turn. However, I need an accurate indication of attitude in order to be able to do that.

farmerjumperdon
2005-Mar-01, 05:44 PM
Guaranteed you will get some funny looks if you pull out a stopwatch and compass in flight. :o I've often thought about bringing my altimeter along just to get a read on what civilization looks like at certain altitudes; but figured it might get taken away at check-in.

Glom
2005-Mar-01, 05:55 PM
It would only work up to 8000ft though.

ToSeek
2005-Mar-01, 06:10 PM
The guy on my flight from LAX to Baltimore had a laptop computer with a GPS receiver and associated software. He could track down just where we were and where we were going. Unfortunately, the software was intended for use in the car: when he tried to use it to see how much farther we had to go, it plotted a route along the highways!

You probably consider that cheating, anyway. ;)

A Thousand Pardons
2005-Mar-01, 07:05 PM
The guy on my flight from LAX to Baltimore had a laptop computer with a GPS receiver and associated software. He could track down just where we were and where we were going. Unfortunately, the software was intended for use in the car: when he tried to use it to see how much farther we had to go, it plotted a route along the highways!

You probably consider that cheating, anyway.
Some GPS receivers have great circle distance calculators, but if yours doesn't that's one way to geek it up--just include a spreadsheet spherical trig great circle solver on your laptop. You could even include correction for the earth's ellipsoidal figure. :)

Torsten
2005-Mar-01, 09:24 PM
"I would like to get a compass, but they don't seem to be commonly sold."

I own 3 or 4 Silva Rangers and a Suunto MC-2 - commonly available here in any sporting goods store. :D

Try obtaining actual runway bearings for Gatwick before departure so that you can calibrate your compass during takeoff for whatever effects the aircraft will have on it. Also take into account the changing magnetic deviation. I don't know how much it varies over the British Isles, but from Newfoundland to Houston it will span ~35 degrees of deviation, and you'll cross the agonic line.

I had my sectionals and old mechanical navigation computer along on a commercial flight down the BC coast one clear, moonlit night and I was able to detemine our location easily from the shapes of the islands and channels.

I used to do all my navigation with just a line marked on the chart and references to landmarks. I really enjoyed that. It's easy when you're up high, but a few times I did longer flights (~500 mi) when the ceiling was low and it was way more work to be certain of position at all times. I was really, really tired after those flights. The plane had no VOR or Loran-C (this was before GPS was commonly available). I haven't done any of that in 16 years.

GPS has made things in my business so much easier. I used to be dropped off by helicopter in small openings in the woods to be picked up at the end of the day at another opening several km away. If it wasn't the same pilot at the end of the day, you'd have to call him in using a radio, but now you simply overfly the pickup point, the pilot records the position in the GPS, and it's no problems. :D It has, however, been known to happen that the field dude doesn't make it to the planned pickup site, and the radio fails. . . For that there are flares, and overnight gear.

sarongsong
2005-Mar-02, 01:34 AM
...I need an accurate indication of attitude in order to be able to do that.
Some boating supply stores (West Marine) carry a simple plastic one.

Waarthog
2005-Mar-02, 01:59 PM
I used to carry my sectionals and such on commercial flights but after the third time I was asked to put them away because it made other passengers nervous (this is 1988-1991 go figure) I stopped.

Swift
2005-Mar-02, 02:53 PM
One of my watches has an altimeter. It seems to give incorrect readings in an airplane. I suspect it is the problem that Glom mentioned. I wonder if the pressurized cabin has something to do with that, since it uses pressure to measure?

There are lots of places to buy compasses in the states; camping stores always have them.

I wonder in this paranoid age, if plotting the position of your flight is a good idea. They might think you are a terrorist calculating when to blow the bomb up. :-?