hate temperature inversions!!!

[z987k]

Anyone else hate these damn temperature inversions? They really keep you from doing about anything. I mean, fog, frz rain, continuous low clouds. I need to ****ing fly!
Look at this **** 0C at the surface and near 20 at the 800mb level.

 

[Orfy]

You mean "Crapy Weather"?

 

[z987k]

yes. But if it would lift this could all go away, or at least make it so I could fly.

but in my experience, what little that may be, this is a big big temperature difference. roughly 20C between the surface and ~5000ft. Thats making it rain up there then come down here and get cold and freeze

 

[Jester369]

I miss my airplane

 

[Jim Karr]

In the days when I was selling advertising on a group of radio stations, we would often experience thermal inversions over Lake Michigan.....You couldn't even hear the local FM signal, and a Chicago station on the same frequency would roar into SW Michigan from across the lake.:rockin:

 

[Yuri_Rage]

During the winter in the Alaskan interior, there is a fairly permanent temperature inversion caused by radiant heating from the ground. It can cause some pretty severe fog and low level clouds that build rapidly and remain rather stationary due to the stagnant, windless air. Talk about a bane to the flying community...

 

[Dude]

z,

I'M IMPRESSED.

Who taught you about inversions?

 

[The Drizzle]

Wow, there seem to be a lot of pilots on this forum. Given the weather around the country I'm surprised I haven't been called in, but that would explain why they haven't released me from reserve duty either.

 

[shafferpilot]

We get 'em regularly all winter long here in Cincy. Alas, Cessnas don't react well to freezing rain. I've been grounded all week, and there really is no relief in site. My local FBO requires that I fly at least 1 hour per 30 days or else I have to do yet another check out flight with a 20 year old instructor that doesn't actually know a whole lot about flying. I just love paying the kid to learn from me

 

[shafferpilot]

z,

I'M IMPRESSED.

Who taught you about inversions?

Pilot training often involves more meteorlogical study than anything else. And when there's anything keeping you on the ground, you get to know it intimately.

 

[The Drizzle]

or else I have to do yet another check out flight with a 20 year old instructor that doesn't actually know a whole lot about flying. I just love paying the kid to learn from me

A lot of us had to start somewhere! If people don't want a 20 year old, they need to be willing to pay more for an IP. Who want's to be a career instructor these days? I would have done it for life if the pay was right.

Back on topic(sorta): The worst I saw was the Valentine's Day Ice storm this past Feb. On approach to CMH the icing actually overcame our aircraft's ability to prevent its formation. I wish i had a camera to show 2inches of clear ice on the leading edge. In the morning the plane was frozen to the ramp, it took 2 de-icing trucks and full reverse thrust to break it free.

 

[mrkristofo]

yeah, we've been known to get them pretty bad around here, too.

Jan of this year:

The pollution associated with these things is atrocious, too. Even by the standards of a friend who was visiting from LA around that time.

EDIT:

I like how this quote applies, with minor modification :

Ski-bumming involves more meteorlogical study than anything else. And when there's no snow on the ground, you get to know it intimately.

 

[z987k]

z,

I'M IMPRESSED.

Who taught you about inversions?

I think shaefferpilot cover that. When you have to sit on the ground all you do is stare at the weather that won't let you go fly.

The rain may be gone now...maybe, but the clouds and visibility are sitting around 300' and 1.5miles. We have no de-icing equipment so... Got to love those stationary fronts that sit on top of you!

Also of note, the lifting index is 33, and yet there is a good deal of convective activity despite the inversion!

 

[Nate]

If I remember correctly, temperature inversions would sometimes cause issues with our radiation monitors at one of the nuclear facilities that I worked at. The lack of air flow would cause the natural alpha emitters (probably radon) to concentrate alpha particles and set off the monitors.

 

[shafferpilot]

A lot of us had to start somewhere! If people don't want a 20 year old, they need to be willing to pay more for an IP. Who want's to be a career instructor these days? I would have done it for life if the pay was right.

My regular instructor is a bit older than that. BUT when I just need a checkout, I get the new guy. Which is fine (and cheaper). I have yet to have any instructor at this school that wasn't competent. Really I'm just whining about having to pay someone to babysit me.

Anyways, I can't wait for those cold, crisp, crystal clear February days. There's nothing quite like flying over Cincinnati and being able to clearly see Lexington, Dayton, and occasionally Columbus rising up on the horizon

 

[Bernie Brewer]

It's been so long since I've flown that when we have an inversion here I don't even think about ceilings, temps aloft, icing, etc. anymore. I just think what good fishing weather it is.

 

[The Drizzle]

Anyways, I can't wait for those cold, crisp, crystal clear February days. There's nothing quite like flying over Cincinnati and being able to clearly see Lexington, Dayton, and occasionally Columbus rising up on the horizon

Amen, last Jan I was over Albany, I could see NYC, BOS, the Mountains in Maine, Long Island and the Jersey Shore. Granted I was up at 370 but that is a long way to see.

 

[z987k]

not to mention the performance is sooo good when it's cold and crisp.

 

[shafferpilot]

not to mention the performance is sooo good when it's cold and crisp.

So true! I actually aborted my first really hot humid takeoff roll, 'cause I thought the engine was screwed up!

Amen, last Jan I was over Albany, I could see NYC, BOS, the Mountains in Maine, Long Island and the Jersey Shore. Granted I was up at 370 but that is a long way to see.

That's awesome. Unfortunately my little 172SP can't quite hit that FL, and considering how dizzying my head gets after half an hour at 110, I doubt I would be able to see much anyways

 

[z987k]

are you serious, at 110, time to stop smoking?

We did an altitude chamber thing at OK city and at fl200, had no ill effects for a lengthy period of time... like 45 mins or so before we went up some more.

 

[shafferpilot]

are you serious, at 110, time to stop smoking?

We did an altitude chamber thing at OK city and at fl200, had no ill effects for a lengthy period of time... like 45 mins or so before we went up some more.

Well, I'm not saying I was ready to pass out, but I do notice the very beginings of the effects above 10,000. Little things like the slow down of conversation. A yawn or two. A little more thinking about things like, "Wow it really is so pretty up here" and "my life is so cool when I get to fly airplanes". I'm an extremely cautious pilot so I don't push things much when the result of a mistake could mean a really bad call to mommy. At 20,000 you might FEEL like you're 100%, but in reality, nobody is truly alert and focused at those altitudes unless they live at higher altitudes. Did they have you running aptitude tests while you were in the chamber? I've watched some videos of people that can't even draw a circle or write their name. Hopefully someday I'll get to take a ride in one of those things, then I'll have a better grip on how far is too far.

 

[e lo]

not to mention the performance is sooo good when it's cold and crisp.

I know beans about planes, but I do love taking my m'cycle to the track early in the season. As long as I can keep my hands warm and my visor fog-free on the straights, it's awesome! My little SV650 pushes probably and extra 4 - 6 HP on cold days when compared to summer.

 

[shafferpilot]

The most profound example of performance vs air density I've ever seen was a high speed run up a mountain highway in South Carolina (ever heard of Deals Gap?) At the bottom of the mountain we were all pullin wheelies on the straights. By the top, my carburetted bike was barely chugging along and blowing smoke 'cause the mixture was SO rich it could barely run. The injected bikes faired much better, but there sure weren't anymore wheelies till we came back down.

 

[e lo]

The most profound example of performance vs air density I've ever seen was a high speed run up a mountain highway in South Carolina (ever heard of Deals Gap?) At the bottom of the mountain we were all pullin wheelies on the straights. By the top, my carburetted bike was barely chugging along and blowing smoke 'cause the mixture was SO rich it could barely run. The injected bikes faired much better, but there sure weren't anymore wheelies till we came back down.

Ah, The Tail of the Dragon. Haven't made it there yet, but it's on my list for sure.

 

[Yuri_Rage]

are you serious, at 110, time to stop smoking?

We did an altitude chamber thing at OK city and at fl200, had no ill effects for a lengthy period of time... like 45 mins or so before we went up some more.

Some folks begin experiencing hypoxic symptoms as low as 8,000', especially if they're acclimated to a near sea-level environment. Don't mess around with hypoxia. If you're feeling dizzy, you need to descend (or use supplemental O2) NOW!

The funny thing (and deadly thing) about hypoxia is that it makes you feel good (and it's usually very insidious). You can certainly remain conscious and feel alert for quite some time at altitudes well above 12,000'. However, the average "time of useful consciousness" at FL200 is about 15 to 20 minutes. After that, you will likely be unable to perform flying related tasks with any degree of proficiency. As you increase altitude above FL200, your time of useful consciousness decreases at an exponential rate, and above ~FL300, you have less than a minute before you will be unable to think rationally.

I've been to hypobaric chamber training 4 times now, and each time I witness the precise reason NOT to mess with hypoxia. IIRC, the general profile is a steady climb up to about FL280 with a stop around FL180 to perform some color vision and aptitude tests. Once you reach the top of the profile, you are told to continue performing simple tasks but to don an oxygen mask as soon as you experience symptoms of hypoxia. Most of the class has their masks on in about 5 minutes or less, and they begin to chuckle about how difficult the simple tasks became as hypoxia set in. There are always one or two idiots who ignore the first symptoms of hypoxia (when they have the capability to think rationally), and they quickly enter a state of euphoria and invincibility. The instructors try to coax these folks into donning their masks voluntarily, but it rarely works. The instructors then begin asking a series of questions like, "Do you think you could fly an airplane right now?" The answers sound like they're coming from delirious drunks. After another minute or two, the instructors forcefully put the idiots' masks on, and the chamber begins a descent profile. Rarely do the idiots remember that they ever acted so foolishly. It's a lesson to everyone that hypoxia can be VERY deadly.

 

[shafferpilot]

Tail of the dragon IS cool..... at least it used to be. Sorry to have to break the bad news, but the state troopers have decided to crack down on that run They're writing speeding tickets like they're goin out of style. They didn't used to do that. When I was there about 6 years ago, I talked to a trooper who was stopped on the overlook. While we talked about a hundred bikes shot by doing about 80mph and the posted limit is 35mph. He said they were there to clean up the mess when someone messed up but they never wrote tickets unless you were really being a jerk. Just this summer a friend of mine went down and got a speeding ticket for doing 50??? Yet another example of big brother "protecting" us from ourselves. It's still beautiful country, though. If you get a chance to go, be sure to hit the "Sky Highway" It's WAY longer than the tail, and it's a really high speed run that goes up to like 8,000 feet or something. Awesome!



20,000 for 45 minutes and weren't a blithering idiot? I'm really impressed!! I lived in Arizona at about 4,500 while back and I had altitude sickness for about a week. it took me about a month to get to where i wasn't winded just walking for 10 minutes.

SWMBO and I were on our way home from North Carolina about two months ago. To get over the mountains and out of the turbulence, we chose to pop up to 11,500 for a bit. On climbout we were chatting like schoolgirls, discussing a couple we are friends with, deciding plans for the evening, etc. Once at altitude, the conversation continued, but had lost its fevered pace. That's when I started thinking about how cool my life was........ but didn't look at a single instrument for about a minute!! Luckily we have talked about high altitude flying many many times, and in the middle of a sentence, she looked at me and said, "Honey I don't feel right". I looked at her and her lips had lost the usual pink color. I took two or three really deep breaths and realized what was going on. "Sorry Baby were gonna have to drop below these clouds, I don't want this plane to end up fuel-less somewhere in Canada!" Hypoxia doesn't hurt, you don't feel like you're choking; you just start daydreaming. It wasn't until we dropped a couple thousand that I realized the full extent of what had happened. Regardless of the regs I don't spend more than 15 minutes above 10,000 anymore.

 

[z987k]

While I'm not the most altitude adapt person living at 754ft... I really don't know why they say useful consciousness is 15-20mins at 20,000 and come to think of it I think is was fl180. Another person in my class, a bicyclist, wasn't feeling it either. Another 7k and things got bad.

Think about this though, I was watching that everest thing on discovery, and they were at like 23,000 and stayed there for the night... no O2. Those number are conservative for the fat flatlanders and such I think.

 

[shafferpilot]

BUT when you go to everest the base of that mountain is over 12,000ft. And the lowest base camp is at 17,700. If you want to climb that mo fo, you have to live at the first base camp for a month to acclimate. And did you see tonight's episode? Even on 100% O2 the guy from Texas had some serious issues! Everyone reacts differently to Oxygen levels. Those sherpas that help people climb everest could get up that sucker in half the time if it weren't for all the winded Americans, Europeans, and Asians holding them back! Check this guy out:

http://www.mounteverest.net/expguide/wwoz.htm

INCREDIBLE

Here's a schedule of how long it takes to get acclimated

http://www.mounteverest.net/expguide/accli.htm

 

[z987k]

I know, doesn't it take like 90 days for your blood to really restructure itself to the low oxygen?

 

[Yuri_Rage]

While I'm not the most altitude adapt person living at 754ft... I really don't know why they say useful consciousness is 15-20mins at 20,000 and come to think of it I think is was fl180. Another person in my class, a bicyclist, wasn't feeling it either. Another 7k and things got bad.

Think about this though, I was watching that everest thing on discovery, and they were at like 23,000 and stayed there for the night... no O2. Those number are conservative for the fat flatlanders and such I think.

Time of useful consciousness is listed as 20 to 30 minutes at FL180. Remember, TUC decreases non-linearly with altitude. Also, these times are for the average person. Smoking, age, physical condition (including altitude acclimation), dehydration, and rapid decompression can all affect TUC.

The times are NOT a guideline for how long you should spend at a given altitude. They are an academic tool used to show how dramatic the effects of high altitude can be to the human body. It's more important to be familiar with the symptoms of hypoxia: dizziness, loss of color in the fingernails or lips, shortness of breath, headache, nausea, fatigue, etc.