Winds at Altitude

I said in an earlier post that Milen and I would be going somewhere to a "far away destination" this week. Perhaps I gave too much away by talking about oxygen systems in my last post, but I really tried not to. :-) And I'm still not going to give away where we're going next, although I am going to say where we went today. You'll just have to stay tuned to the blog and come back for more updates.

Today's leg took us to South Lake Tahoe (KTVL). We took off from Paine Field and filed via airways to Medford (KMFR) where we would switch seats, grab some food, and continue on to Tahoe (we flipped for legs the day before; I ended up getting Paine-Medford). Although I was slightly afraid of icing, we did not pick up any ice on ascent to our cruise altitude (9,000 feet), and in fact, the cloud tops were only at 8,000. We ended up making it to Medford in 2 hours, 20 minutes - not necessarily because we had a super-fast airplane (we took the G1000 Cessna 182), but because of very strong winds aloft. We consistently ended up with about a 35-40 knot tailwind!!

Medford had a 4,000 ceiling, so we had to get out of there IFR. And as far as getting to Tahoe from Medford, one can do it in a couple of ways. The first option is to go south towards the Fort Jones VOR, then south through Red Bluff and finally swing east at some point. The second option is to go east to Klamath Falls, and then go south towards Reno. The advantage of the first route is that it doesn't require oxygen at the MEA -- the second route, on the other hand, has a MEA of 14,000 feet.

Which brings us back to the oxygen post. There was a reason that I posted it... Milen and I realized that for maximum flexibility, we needed a portable oxygen system. Since we could not rent one, we called up MyPilotStore, and we had a nice 9 cubic-foot system shipped overnight ($68 extra, ouch). Using cannulas (approved for use up to 18,000 feet), this size system gives approximately 4 hours of endurance to 2 people. Of course, as we learned from the guy who filled the tank, you don't want to run the tank dry because tanks that have been run dry have to be purged by a specially qualified technician (who usually is not your typical line guy who does oxygen system fillups). So it's really perhaps 3 or 3.5 hours of endurance for two.

We got oxygen to get us more flexibility, and we needed it on this trip! It wasn't because we chose the Klamath Falls route on purpose. Rather, the winds aloft were extremely strong today. Recall that between Paine and Medford we got a constant 35-40 knot tailwind; between Medford and Reno, the winds were forecast to be in the 50 knot range. You certainly do not want to fly low over the mountains in such winds: turbulence and downdrafts often exceeding the climb capabilities of a small piston-driven airplane may be encountered. However, if you climb high above the terrain, the danger of downdrafts lowers. Therefore, we decided that 15,000 feet via Klamath Falls and Mustang VOR's was the best way to go. The terrain in that area is just over 8,000 feet or so for most of the route, so we would have an adequate safety margin. (Of course, the winds were stronger than forecast -- we've seen as high as 61 knots on the GPS display -- which also translated into more than 200 knots on the groundspeed; overall, that leg of the trip was a little under two hours).

Where are the pictures? There aren't that many yet - but, we've got a full video of an approach to Medford, and a video of landing at South Lake Tahoe. I'll be uploading those to YouTube as soon as I get back to Seattle! Of course, I'll post a link on the blog as well. :-)

Come back tomorrow for another installment from our trip! (Hopefully the net connection will work as well tomorrow as it did today!)