High altitude advice?

deyoung

deyoung

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Chris
Soliciting opinions, advice, and general input on the idea of taking a Cherokee-235 based in Tucson into C08.

My model of Cherokee lists a service ceiling of around 12,500 (and my experience says this is not far off), and the field elevation at C08 is about 8,300. I have done a basic mountain flying course, but it was here in the desert southwest and I don't feel like it really addresses the Colorado high terrain.

On the other hand, it would likely be just me in the plane, with basic luggage, so even with fuel to spare I won't be too heavy. On the third hand, a 6000-foot and change runway that sounds long normally, maybe isn't so long at 8,300'?

Looking for input from those with more high altitude experience. Thanks!!
 
Not quite that elevation but I hired an instructor to take me into Glenwood Springs in a 160 hp 172, altitude is a bit lower but the runway is half the length.

Run the performance numbers in the POH. That will tell you pretty much what you need to know. Do a proper runup to ensure the mixture is set to the elevation. That’s standard pretakeoff procedure here at 4200’. Lightly loaded and 6000’ feet shouldn’t be an issue. Run the numbers though.
 
Lean properly, follow the numbers, be prepared to climb languidly, you should be fine.
 
I have nothing else to add except that I'm glad this is a Cherokee 235, and not something lesser.

I regularly fly in/out of Flagstaff, AZ, and many pilots get a lot of butt-pucker there even with a 9,000-foot runway. So, yeah, a 6,000-foot runway leaves lots to be desired. I have not-so-fond memories of flying a mighty Warrior in and out of there a few times.

  • Use all the runway
  • Adjust mixture for full power
  • I like to lift-off when able and accelerate in ground effect
  • Patiently wait for "I think I can, I think I can..." to become "I knew I could, I knew I could.."

I looked up the airport on the VFR chart, and it appears surrounding terrain is mostly forgiving. You have nothing much preventing you from using the local area to slowly climb to 10,000+.

You're approaching this with the correct mindset. So long as it's not hot, I believe you'll be fine. (BTW, "hot" can be anything above 60 degrees)
 
Thanks everyone! This would probably not be until summer, so it might be on the warm side (relatively speaking, though it won't feel like it to me coming from Tucson :) ). Canon City (1V6) might be a better alternative; lower, and more services (I'll need a rental car either way), and the runway is likely in better condition.
 
I don't have any experience in a Cherokee 235, but in the Cessna counterpart (182) with one person, light on weight, I would have no concerns about this under reasonable circumstances. You'll definitely have crappy climb rates, but fly your airspeeds and you'll be fine.

- Fly mornings only
- Lean for max power on takeoff
- Don't unnecessarily tanker gas; keep your weights light
- Don't fly when the winds are up (see fly mornings only)
- Gain speed in ground effect, don't yank it off; let the plane fly when it wants to fly
- Expect really crappy fpm climb rates, like 100-300 fpm and remember as long as you're going up and terrain is going down, you're good (for the moment)
- Know which way is downhill. Even if it's as subtle as which way the rivers flow, terrain that drops away is really important. Never fly into rising terrain unless you already have the altitude.
- Don't fly unless it's pretty much a bluebird day and in the morning; be super conservative on weather and wind
 
deyoung said:
Soliciting opinions, advice, and general input on the idea of taking a Cherokee-235 based in Tucson into C08.

My model of Cherokee lists a service ceiling of around 12,500 (and my experience says this is not far off), and the field elevation at C08 is about 8,300. I have done a basic mountain flying course, but it was here in the desert southwest and I don't feel like it really addresses the Colorado high terrain.

On the other hand, it would likely be just me in the plane, with basic luggage, so even with fuel to spare I won't be too heavy. On the third hand, a 6000-foot and change runway that sounds long normally, maybe isn't so long at 8,300'?

Looking for input from those with more high altitude experience. Thanks!!
Click to expand...
Going for the music festival? The Silver West elevation isn't the issue, it's the density altitude, as you know well,
If landing at Canon City (Fremont County) wave to everyone at Super Max as you fly over. Rental cars are outlandish at 1V6 - county atty declared years ago that only county employees may use the "crew cars" so many Colorado pilots avoid it, even during the open house and air show. Last time I looked, a car was $50+ per day.

If just going for fuel, consider Spanish Peaks, just to the east. Lower altitude all the way around. But since it's unmanned, not easy to get a rental, but Gary (manager) might be able to make something happen.

For comparison, check out the Airnav comments on all 3 airports.
 
Last edited:
murphey said:
Going for the music festival?
Click to expand...

No, I have some land north of Westcliffe that has been sitting neglected for a long time and at some point I need to go out there and check on things. Canon City is about 30 minutes farther away from where I'd be going, compared to Silver West. I might also consider Colorado Springs -- another hour or so of driving, but I've flown in and out of there a couple of times before, and I have some family there I could visit at the same time. And it sounds like rental cars might be cheaper. :)
 
deyoung said:
Soliciting opinions, advice, and general input on the idea of taking a Cherokee-235 based in Tucson into C08.

My model of Cherokee lists a service ceiling of around 12,500 (and my experience says this is not far off), and the field elevation at C08 is about 8,300. I have done a basic mountain flying course, but it was here in the desert southwest and I don't feel like it really addresses the Colorado high terrain.

On the other hand, it would likely be just me in the plane, with basic luggage, so even with fuel to spare I won't be too heavy. On the third hand, a 6000-foot and change runway that sounds long normally, maybe isn't so long at 8,300'?

Looking for input from those with more high altitude experience. Thanks!!
Click to expand...

I've flown a Cherokee into LXV (highest airport in the U.S, IIRC). There was nothing to it. Just don't go at full gross weight. Book numbers may be optimistic for an old airplane. Also, don't combine risk factors. The high altitude is risky enough, you don't want to add other things like weather, weight and low fuel into the mix.
 
Remember that your V speeds are indicated, which will be noticeably lower than true at higher density altitudes. You fly the indicated speeds, but you will feel like you are moving too fast based on what you see out the window.
 
Thanks, all good advice! I appreciate it.

What I really should do it do a real Colorado-based mountain flying class; I'd like to do the one murphey posted about recently, though I don't know if it'll be practical for me to get up there for it or not.
 
Do it in cooler weather. A summer afternoon departure could prove very interesting.
Watch your density altitude.
 
Zeldman said:
Also, don't forget to lean properly. It will make a difference on the take off run. (worth saying twice)
Click to expand...

You probably experience some pretty high density altitudes out there in Gallup. You're only 30 or so miles away from the Continental Divide, right?
 
3393RP said:
You probably experience some pretty high density altitudes out there in Gallup. You're only 30 or so miles away from the Continental Divide, right?
Click to expand...

Yeah, about 30 miles or so. But it is a low part of the divide, only around 7200 feet.

Normal density altitude will be around 9500 in the summer. Later in the afternoon it can be over 10,000. Right now at 0955 the temp is 50f and the DA is 7100. Gonna be a nice spring day if the wind stays under 40..!!!
 
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