in-flight visibility

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Rich
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in-flight visibility

Post by Rich »

We've had exceptionally sunny weather here in Central Oregon all summer. But we've had ridiculous amounts of smoke in the air for like the last 6 weeks, almost non-stop. (Brief break during eclipse weekend, strangely.)

Last Saturday on a VFR flight from Portland to Prineville I was flying in the biggest gap between TFRs over the Cascades that we have (there are fires all over the place). It was approaching sunset (landed about 8:00 PM local), thankfully with the sun at my 5 O'clock. At 7,500 ft. I really couldn't tell you what my level-flight visibility was. Could have been 5 miles, could have been 100 ft. I could make out surface features 2,000-3,000 ft. below a few miles head (3-4?), but there was no way to tell visibility looking level at my altitude. I was with ATC (flight following) and traffic into Redmond (KRDM) was typically requesting vectors and clearance for one instrument approach or another.

After passing over the higher ground I descended to 6,000 ft. Shortly after leveling ATC asked if I'd like an instrument approach into Prineville. I declined, as the visibility now was easily 10 miles or more, based on how far I could see surface features, though the smoke was still a factor. One could still not see a horizon in any direction. I surmise I had been flying through really limited visibility at altitude but could see surface features a few miles head only because it was somewhat thinner below me.

The flight was uneventful, really, but it got me thinking about the very nature of evaluating in-flight visibility. For sure, had it been night, it would effectively been zero-zero as far as seeing any unlighted objects. All this without a "cloud" in the state.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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Lou
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Re: in-flight visibility

Post by Lou »

Lots of smoke here as well. It really sneaks up on you. Getting the instrument rating was a good idea for unexpected reasons.
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