Safely flying near shorter mountains

[Sac Arrow]

Got any suggestions?

PM sent.

 

[Silvaire]

There aren't really very many high altitude airports in California outside of Truckee, Tahoe and Mammoth. Most of the airports in the Sierra foothills are under 3,000 feet with the exception of Nyack.

For the original poster: what you are doing isn't really what would be considered mountain flying because, for one thing, you can just fly completely over those ranges, there's no need to be actually flying in them and even if you are flying in them for the purposes of sight seeing you can just climb out of them if you want. At the same time however you shouldn't underestimate them. The northern Santa Lucia range along the coast at Big Sur is pretty rugged and desolate as is the middle Diablo range between Livermore and Hollister despite being in fairly close proximity to one of the largest metropolitan areas in the country.

The main thing you need to be concerned with is turbulence. I'm not talking about something that will snap your airplane into fragments but something that can make the experience for both you and your passengers anywhere from unpleasant to terrifying. At this time of year it's probably best to avoid anything in the mid to late afternoon time frame or, as the case has been for the past week, when there are winds over 20 knots.

The coast north of San Francisco up to Pt Reyes is pretty spectacular too and not as hairy as Big Sur so consider it as an option.

 

[MAKG1]

Got any suggestions?

The guy I learned from the first time was an old crusty flight instructor at KWJF -- in a rather interesting FBO with some history (it belonged to Pancho Barnes before she died). It's a bit far, and hot as hell this time of year. He had us take a 160 HP Warrior with half fuel up to Big Bear in spring, with density altitude around 8500. Not much canyon flying there, but lots of ridge flow and turbulence to deal with (curiously, not so bad in the valley, but north of Wrightwood, it knocked us around hard), and of course the density altitude. 5800 feet sounds like a huge runway, and it's ample for those conditions, but it seems shorter than you might think when you try it.

I haven't flown with these guys, but there is an FBO at KTRK with light Cessna rentals. Kinda hard to avoid mountain flying when the airport is IN the mountains....one of the aircraft they list is a 172N, just like 9ZL, and it may be really instructive to feel the differences. I guess 27H has been down the whole time you've been around, so you haven't had a chance to try a 172M. They are really similar, except for the flap switch and 10 missing HP.

I've tried twice to get some serious mountain training at Peak Aviation in KCOS. Instructors seem REAL good, but the schedule has always been to tight to deal with the weather. It ALMOST worked last time around, except that last round of really nasty fires occurred the day before the planned flight, and effectively blocked all of the passes we considered from Denver to Taos. We were planning canyon approaches into Aspen and Creede, in a 172XP (195 HP 172 with a CS prop -- the marketing solution to the bad rep the 177 got). Would have been great....

I believe there are outfits in Auburn and Oroville.

 

[EdFred]

It's the DA ops they're considering.

I know, but a mountain course isn't quite attacking the problem if the issue is DA ops. If you want to simulate the DA ops, without going to a higher altitude strip, don't give it full throttle on takeoff from your home airport. Easy peasey.

 

[joycem137]

For the original poster: what you are doing isn't really what would be considered mountain flying because, for one thing, you can just fly completely over those ranges, there's no need to be actually flying in them and even if you are flying in them for the purposes of sight seeing you can just climb out of them if you want. At the same time however you shouldn't underestimate them. The northern Santa Lucia range along the coast at Big Sur is pretty rugged and desolate as is the middle Diablo range between Livermore and Hollister despite being in fairly close proximity to one of the largest metropolitan areas in the country.

The main thing you need to be concerned with is turbulence. I'm not talking about something that will snap your airplane into fragments but something that can make the experience for both you and your passengers anywhere from unpleasant to terrifying. At this time of year it's probably best to avoid anything in the mid to late afternoon time frame or, as the case has been for the past week, when there are winds over 20 knots.

The coast north of San Francisco up to Pt Reyes is pretty spectacular too and not as hairy as Big Sur so consider it as an option.

This is *exactly* the kind of information I was looking for. Thank you so much. We went down there on Sunday just looking for sight seeing, and I wanted to be sure that we did everything right. Sounds like I was more than safe: I was more careful than I needed to be, and that, frankly, is a good thing.

 

[MAKG1]

I know, but a mountain course isn't quite attacking the problem if the issue is DA ops. If you want to simulate the DA ops, without going to a higher altitude strip, don't give it full throttle on takeoff from your home airport. Easy peasey.

That's not all there is to it. The higher ground speeds make for some interesting patterns, and you can't simulate that with the throttle.

And it's not an option at PAO. 2400 feet is fine at sea level, but it's excessively short for high DA. Heck, the 4000 feet at Lee Vining looks kinda short when it's 85 deg out (BTDT).

Setting the throttle is really easy with an MP gauge (1 inch per thousand feet), but it's a bit of a guess for fixed pitch.

 

[Dave Krall CFII]

I know, but a mountain course isn't quite attacking the problem if the issue is DA ops. If you want to simulate the DA ops, without going to a higher altitude strip, don't give it full throttle on takeoff from your home airport. Easy peasey.

That's only an easy start, mostly good for just take-off eye-opening, I've been taught it and still teach it.

 

[denverpilot]

That's funny. There's quite a few non-moutainous airports above 3500MSL in the country. Evidently Californians consider eastern CO and NM, and the OK panhandle mountainous.

It's all what you're used to... Note DA here today...

I get surprised at how well the bird lifts off and climbs when I go downhill.

 

[MAKG1]

It's been higher than that this year....

Now, try to imagine some green flatlander flying up from sea level for the first time, and trying to start and run up the engine full rich. If they have half a head, the coughing and sputtering may make them taxi back and think the plane is broken. If they are total idiots, they take off that way and make a smoking hole. This is the scenario the club (and their insurance) is presumably trying to avoid.

They get confused because some of the checklists -- and even the Cessna 172N POH -- say to use full rich for some steps (with no qualification), but there is never a time at such high density altitude where that's the best thing to do. You might get engine start to work (but not optimally), but the go-around is going to be a big problem if you follow the descent and before-landing checklists literally.

 

[Jthamilton]

I know, but a mountain course isn't quite attacking the problem if the issue is DA ops. If you want to simulate the DA ops, without going to a higher altitude strip, don't give it full throttle on takeoff from your home airport. Easy peasey.

Yep, if I take off at 23inches instead of my normal 32 that simulates a normally aspirated engine instead of my turbo and provides a completely different perspective on a 9000' DA day. This at 7000 foot field.

 

[EdFred]

Yep, if I take off at 23inches instead of my normal 32 that simulates a normally aspirated engine instead of my turbo and provides a completely different perspective on a 9000' DA day. This at 7000 foot field.

My highest DA was 11.400 at Bryce Canyon in 2005. Acceleration wasn't all that much slower. Ground roll wasn't that much more. But it didn't want to climb at all. Good thing I was on top of a mesa.

 

[midlifeflyer]

Yep, if I take off at 23inches instead of my normal 32 that simulates a normally aspirated engine instead of my turbo and provides a completely different perspective on a 9000' DA day. This at 7000 foot field.

Those living at sea level should realize that the reduced power takeoff isn't a complete simulation since it only deals with engine output, not airfoil (which includes prop) efficiency.

Having flown in the mountains of the west and the east, both have my respect.

 

[Sac Arrow]

If you're taking off from a high DA airport, a good technique to use is a soft field technique, particularly if runway length is limited. Get off the ground early, and accelerate to Vy in ground effect.

 

[EdFred]

Why would I want to induce extra drag on the t/o roll?

 

[bnt83]

Why would I want to induce extra drag on the t/o roll?

+1



Why would you?

 

[bnt83]

High DA,

Shortfield takeoff

Accell in ground effect

Retract gear

continue on


Doesn't sound right to me.

 

[Sac Arrow]

Why would I want to induce extra drag on the t/o roll?

Who are you responding to, me?

High DA,

Shortfield takeoff

Accell in ground effect

Retract gear

continue on


Doesn't sound right to me.

Nor to me (particularly since that wasn't what I said.)

Normal takeoff

Stay in ground effect, retract gear, if applicable

Accel to Vy in ground effect

Continue on

It's what I was taught, works quite well. What you want to avoid is settling back down on the field after you leave ground effect, particularly if you have no runway left.

 

[denverpilot]

That will shorten your ground roll but significantly lengthen the distance needed to clear an obstacle. It becomes very dramatically clear in the POH addendum for our STOL kit.

 

[Everskyward]

Those living at sea level should realize that the reduced power takeoff isn't a complete simulation since it only deals with engine output, not airfoil (which includes prop) efficiency.

Having flown in the mountains of the west and the east, both have my respect.

This...

 

[MAKG1]

Who are you responding to, me?



Nor to me (particularly since that wasn't what I said.)

Normal takeoff

Stay in ground effect, retract gear, if applicable

Accel to Vy in ground effect

Continue on

It's what I was taught, works quite well. What you want to avoid is settling back down on the field after you leave ground effect, particularly if you have no runway left.

Don't retract the gear in a Cessna retract while in ground effect. You'll leave ground effect, but not in the way you intended. At least 100 AGL.

 

[Sac Arrow]

Don't retract the gear in a Cessna retract while in ground effect. You'll leave ground effect, but not in the way you intended. At least 100 AGL.

Dependent on airplane of course. Same with the use of flaps.

 

[EdFred]

Who are you responding to, me?
Nor to me (particularly since that wasn't what I said.)

Memory issues?

If you're taking off from a high DA airport, a good technique to use is a soft field technique, particularly if runway length is limited. Get off the ground early, and accelerate to Vy in ground effect.

Soft field induces more drag.

 

[Sac Arrow]

Memory issues?

Soft field induces more drag.

High DA,
Shortfield takeoff

Reading issues?

I agree with you that a strict soft field takeoff, where you hold the stick back and rotate the nose early adds more drag. I'm not suggesting that. I'm suggesting that you accelerate to Vy (or Vx, as the case may be) in ground effect before climbing out.

I suppose if you normally rotate at those speeds anyway, the issue is moot.

 

[EdFred]

Reading issues?

I agree with you that a strict soft field takeoff, where you hold the stick back and rotate the nose early adds more drag. I'm not suggesting that. I'm suggesting that you accelerate to Vy (or Vx, as the case may be) in ground effect before climbing out.

I suppose if you normally rotate at those speeds anyway, the issue is moot.

Your first post, which was the only one I could have been responding to at the time, suggested a soft field take off. Make up your mind. I never suggested a short field takeoff. Why are you quoting bnt?

 

[Sac Arrow]

Your first post, which was the only one I could have been responding to at the time, suggested a soft field take off. Make up your mind. I never suggested a short field takeoff. Why are you quoting bnt?

Because you quoted my response to bnt's reply to my original post, he said short field takeoff, although probably unintentionally.

But whatever, I'm done arguing semantics.

 

[MAKG1]

FYI, for the locals, including the OP:

"Safe Flying in the Mountains is No Accident!"
Topic: High altitude flying, A/C performance, Density Altitude, Physiological Effects, Mountain Weather and Mountain Flying.
On Saturday, August 10, 2013 at 9:00 AM
Location:
Sterlng Aviation
145 John Glenn Drive

Concord, CA 94520
Select Number:
WP1751216
Description:
Recent accidents in Truckee, South Lake Tahoe, and the surrounding area suggest a need for us to study and learn from those who have accumulated a life time of safe flying in the beautiful but unforgiving environment of mountain flying.
To view further details and registration information for this seminar, click here.
The sponsor for this seminar is: FAASTeam
The FAA Safety Team (FAASTeam) is committed to providing equal access to this meeting/event for all participants. If you need alternative formats or services because of a disability, please communicate your request as soon as possible with the person in the 'Contact Information' area of the meeting/event notice. Note that two weeks is usually required to arrange services.
The following credit(s) are available for the WINGS/AMT Programs:
Basic Knowledge 3 - 1 Credit

 

[Dave Krall CFII]

Those seminars are very good and usually have some good pixs, maybe even actual video.

FYI, for the locals, including the OP:

"Safe Flying in the Mountains is No Accident!"
Topic: High altitude flying, A/C performance, Density Altitude, Physiological Effects, Mountain Weather and Mountain Flying.
On Saturday, August 10, 2013 at 9:00 AM
Location:
Sterlng Aviation
145 John Glenn Drive

Concord, CA 94520
Select Number:
WP1751216
Description:
Recent accidents in Truckee, South Lake Tahoe, and the surrounding area suggest a need for us to study and learn from those who have accumulated a life time of safe flying in the beautiful but unforgiving environment of mountain flying.
To view further details and registration information for this seminar, click here.
The sponsor for this seminar is: FAASTeam
The FAA Safety Team (FAASTeam) is committed to providing equal access to this meeting/event for all participants. If you need alternative formats or services because of a disability, please communicate your request as soon as possible with the person in the 'Contact Information' area of the meeting/event notice. Note that two weeks is usually required to arrange services.
The following credit(s) are available for the WINGS/AMT Programs:
Basic Knowledge 3 - 1 Credit