Safely flying near shorter mountains

joycem137

joycem137

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Novi, MI
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Robin
Just got my pilot's license a few weeks ago, and have been enjoying flying around with it. One thing I want to do soon is get training for how to deal with flying near and around and into mountainous regions. I understand there's some specific and special techniques related to it, and my flying club requires it before I can land at a place over 3500 MSL.

Until I get that training, I've been trying to stay away from mountains. But I had an interesting challenge posed to me yesterday when I took a friend on a tour of the area, and he wanted to fly around Big Sur and Pinnacles National Monument. I realized that I didn't have a good sense of when flying became "mountain flying," and thus dangerous without more knowledge/training. Basically, when I was moving from my "known unknowns" to "unknown unknowns."

Let me put it this way. I've flown over many 3000 foot "mountains" in the area throughout training, since the SF bay area is surrounded by such things. I've heard of no indication that this is "mountain flying." But what about 5000 MSL mountains? 6000 MSL? If the peaks are 2000 feet below me and miles to the side, do I need to worry much about it?

For the time being, I'm staying well away and above mountain ranges that cover a large area. At least until I figure out if I'm missing any information that might put me in danger. When I flew through around those areas this weekend, I made sure I always had a flat place in sight/range that looked good for an emergency landing, if necessary. I stuck to the valleys and basically avoided flying into the mountainous regions at all. Just to the side of them so that we could get a nice view.

EDIT: Obviously, I was also staying clear of the national park restrictions in the area.
 
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What's the elevation from the base of the mountain to the top? Generally the "rule" for avoiding the rotors if the wind is over 15kts, is take 1/2 that number and fly over the top. So if the top of the mountain is 6,000 and the valley floor/base of it is 4,000 you would take that difference, halve it and make sure to fly at least that distance above it. So 1,000 above the 6,000MSL.

If you are approaching the ridge and cant see anything on the other side, you need to climb.

Also, approach ridges at a 45 degree intercept so in case you can't climb/get hit with a downdraft on the lee side, you can more easily turn back/away from the ridge.

Those are three for starters.
 
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EdFred said:
What's the elevation from the base of the mountain to the top? Generally the "rule" for avoiding the rotors if the wind is over 15kts, is take 1/2 that number and fly over the top. So if the top of the mountain is 6,000 and the valley floor/base of it is 4,000 you would take that difference, halve it and make sure to fly at least that distance above it. So 1,000 above the 6,000MSL.

If you are approaching the ridge and cant see anything on the other side, you need to climb.

Also, approach ridges at a 45 degree intercept so in case you can't climb/get hit with a downdraft on the lee side, you can more easily turn back/away from the ridge.

Those are three for starters.
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What about maintaining emergency landing places? I stayed away from the mountains because I'm not really sure if/how I would do an emergency landing when directly above them. Instead, I figured I'd stay well to the side where I could easily see flat land I could glide to.

(I'm trying to be very cautious and slow in expanding my flying environments. I don't want to expand too quickly and get in too deep.)
 
joycem137 said:
What about maintaining emergency landing places? I stayed away from the mountains because I'm not really sure if/how I would do an emergency landing when directly above them. Instead, I figured I'd stay well to the side where I could easily see flat land I could glide to.

(I'm trying to be very cautious and slow in expanding my flying environments. I don't want to expand too quickly and get in too deep.)
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Fly down the drainage, if the terrain is too steep for an emergency landing, it is likely descending at an angle greater than your glide angle.

Also, don't fly up the center of valleys, fly along the down draft side. This will give you more room to turn around if needed and mean that you won't be turning into worse air.
 
If you're going to Pinnacles, stay in sight of KKIC and you'll be fine. There are LOTS and LOTS and LOTS of emergency landing spots in the Salinas Valley. Many open fields, and a few private airstrips on the eastern side (not all of them charted).

The highest (well, actually, the only) ridge you need to cross to get there is the one between Gilroy and Salinas, barely over 1000 feet. This will also place you upwind of the mountains, though you'll get some turbulence from the Santa Lucia range to the west.

The eastern route over Hollister isn't so great a view at the altitudes you need. The terrain is significantly rougher there, though there are still flat spots. Don't hit the cows. There are a lot of them. Hwy 25 is completely unsuitable. And if you want to actually see the mountains, you'll need to be low enough that the turbulence is going to be a factor. And the birds. There are a TON of turkey vultures there, and they like to soar the thermals. And condors. Those require 3000 AGL clearance, which kinda sucks for sightseeing (but, stay west of the park over the valley floor, and you're good to go lower).

In a nutshell, it's mountain flying when your aircraft performance becomes a factor for dealing with the winds and terrain clearance. Terrain clearance won't be a factor anywhere in the Coast Ranges in a 172, but winds might be under some circumstances. I wouldn't go out on a red flag day, but even with 20+ knot winds, you'll be fine (if a bit jostled) over the valley floor. The Salinas Valley is not the Owens Valley. It's not that bad. If you don't like how you're being bounced, climb. It's likely to be baby's-butt smooth much above 4000 feet, as the winds are coming directly off the Pacific up there. Expect ridge lift west of the park if there is significant wind.

Make sure you have flight following if you get anywhere near KKIC, as that's where Sean Tucker runs his aerobatics school.

The club rules are about planned high altitude landings, which is actually the easy part. There aren't any high altitude airports anywhere near the Salinas Valley.

When in doubt, read Sparky Imeson's book.
 
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Skylane81E said:
Fly down the drainage, if the terrain is too steep for an emergency landing, it is likely descending at an angle greater than your glide angle.

Also, don't fly up the center of valleys, fly along the down draft side. This will give you more room to turn around if needed and mean that you won't be turning into worse air.
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Did you mean downwind/updraft side?
 
There's no cut and dried line for a "mountain flying" threshold.

It's more about tight flying in generally high to very high DA, combined with variable pilot/aircraft performance into typically short, multiply obstructed runways and subjected to amplified, unknown mountain winds and weather, among other considerations.

Technically, one could fly high over mountainous terrain, maybe only catch a little mountain wave, and that would be mountain flying. But if you read some of the standard books like: Fly Idaho by Hanselman or, Mountain Flying by Sparky Emesson, you will see there's much to it that their experience quickly reveals.

A quick flying course by a qualified CFI into actual runways with a high Runway Hazard Index is an eye opener to anyone that hasn't actually flown into one and invaluable.
 
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joycem137 said:
What about maintaining emergency landing places? I stayed away from the mountains because I'm not really sure if/how I would do an emergency landing when directly above them. Instead, I figured I'd stay well to the side where I could easily see flat land I could glide to.

(I'm trying to be very cautious and slow in expanding my flying environments. I don't want to expand too quickly and get in too deep.)
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Sometimes, there just isn't going to be a landing spot. That's not just for mountainous flying. When over Northern Wisconsin, Michigan, and Minnesota, you're gonna be in the trees - or a lake.
 
Dave Krall CFII said:
There's no cut and dried line for a "mountain flying" threshold.

It's more about tight flying in generally high to very high DA, combined with variable pilot/aircraft performance into typically short, multiply obstructed runways and subjected to amplified, unknown mountain winds and weather, among other considerations.

Technically, one could fly high over mountainous terrain, maybe only catch a little mountain wave, and that would be mountain flying. But if you read some of the standard books like: Fly Idaho by Hanselman or, Mountain Flying by Sparky Emesson, you will see there's much to it that their experience quickly reveals.

A quick flying course by a qualified CFI into actual runways with a high Runway Hazard Index is an eye opener to anyone that hasn't actually flown into one and invaluable.
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I plan on taking some mountain flying training and doing a bunch of reading on the subject in the next couple months, but I haven't had the chance to do so yet and want to make sure that my decision making process is safe until I take the time to do that study and training.
 
Old (but still I believe still relevant) FAA mountain flying training video:


While somewhat specific to Idaho, here is a video on mountain flying, produced by Idaho Division of Aeronautics (part 1 of 2):
Part 2:
http://www.youtube.com/watch?v=NHHeJrEsQ9I

EDIT: Found a version of the FAA video all in one part.
 
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Yet another FAA video on mountain flying; this appears to be more recent:

 
Those classic videos from the Idaho Bureau of Aeronautics and the FAA are a great place to start, and further study will quickly show an astute flight student just how much more there is to the subject of mountain flying than they provide.
 
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Many of the respondents here may be unfamiliar with the area.

The highest terrain around there and at intermediate points is barely over 5000 feet. The target itself is closer to 3000. ALL the airports in the region are under 500 feet elevation. Immediately to the west of the target area is a 5 mile wide FLAT valley with a floor just above sea level. The entire route of flight can be done easily at 2500 and 3500 MSL if that is desired.

The biggest constraint is the DOI prohibition on flight under 3000 AGL over the national park. And the birds. They are BIG birds.

This is not serious mountain flying, and it's not backcoutnry flying. It's rural, the closest thing coastal California has to the plains flying most of the eastern guys do. Joyce, plan this like any other cross country. You may have already done one to Salinas as part of your training. Aircraft performance is not going to be an issue.

This is NOT any more difficult than the usual student cross-countries out to Modesto or Gustine, as long as you stay west of the national park.

But it may not be the best time to go there. There is a fire well to the west of there near Ventana, and visibility may not be too good due to the smoke. If serious, it will show up on vis satellite.

See the local area here:
http://skyvector.com/?ll=36.46142223968958,-121.28109741426191&chart=301&zoom=1
 
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MAKG1 said:
This is NOT any more difficult than the usual student cross-countries out to Modesto or Gustine, as long as you stay west of the national park.
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Eh, here's the thing. There are known knowns, known unknowns, and unknown unknowns. I know that there are some things about mountain flying that I don't know very well, but I really don't know how much I *don't* know. So I'm carefully avoiding anything resembling mountains until I assemble enough information to make sure that the "unknown unknowns" are few.

The flight club owner jokes with me that she and I are both "chicken pilots." :) "But hey, a chicken pilot is a living pilot." :yes:

ADDED: Basically, reading through these forums and reading crash reports has made me want to be super careful. In the 11 hours I've logged since getting my PPL, only two flights were not flights I've done many times as a student. I'm starting slow and super careful, slowly checking out new areas, slowly getting more of a feel for what I didn't learn in training, and what I may have learned but not learned as well as I'd like, etc.
 
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How can you fly around the region at all while avoiding things resembling mountains?

There are some pretty good ones less than 10 miles west and east of PAO.

Seriously, the highest mountain around the Bay Area is about 4200 feet -- it's either Mt. Diablo or Mt. Hamilton (they are comparable). You're considering flying near a 3000 foot peak and worried whether it's a "mountain." If you've ever flown to KHAF over OSI (like we all like to do), you've been flying around 3000 foot peaks. The terrain you're talking about overflying is similar to crossing Sunol Pass, which you probably did in the majority of your student pilot flights.

In many respects this is a safer flight as there are a LOT more opportunities to put the plane down in a lettuce field or private runway or even on US 101 than there is around the Bay. The one bugaboo is the frickin' birds. They are bigger than the usual PAO Canada geese, but not by much.

You've done all this. You know what it's like in the wind in Sunol Pass, right? That's what you can expect on a bad day.

For a "chicken pilot," Heather does a lot of flying in the Sierra foothills. She's told you where she lives, right?

It's prudent to feel out your limits gradually. But I don't think this is anywhere near your limits. Of course, as PIC, your opinion on that is all that really matters.

To find out what you don't know, I'd suggest reading Sparky Imeson's book. Evan has a copy. EdFred posted an approximation of the Cliffs Notes version (the remainder is density altitude and emergency maneuvers).
 
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MAKG1 said:
How can you fly around the region at all while avoiding things resembling mountains?

There are some pretty good ones less than 10 miles west and east of PAO.

Seriously, the highest mountain around the Bay Area is about 4200 feet -- it's either Mt. Diablo or Mt. Hamilton (they are comparable). You're considering flying near a 3000 foot peak and worried whether it's a "mountain." If you've ever flown to KHAF over OSI (like we all like to do), you've been flying around 3000 foot peaks. The terrain you're talking about overflying is similar to crossing Sunol Pass, which you probably did in the majority of your student pilot flights.
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In training, I was always flying in places where I was only near mountains, but the terrain beneath me was very flat, such as through Sunol, or near livermore, or over the mountains to half moon bay. I'd never flown over areas such as Big Sur, or the mountains directly to the east of San Jose around BORED, or the Santa Cruz mountains near Bonny Doon, or other large ranges, and that's the sorts of areas I'm asking about. Mountain ranges that are more than a straight line of peaks between me and where I'm trying to get. Where I'm actually *over* the mountains for an appreciable amount of time, and not just passing over briefly.

Since that's something I haven't done before, I want to make sure its safe before I attempt it. :)
 
That's what it's like over there, too. Near mountains, very flat.

Sunol's not that flat. It's 1000 feet above the surrounding valleys, hemmed in by overlying Class B. And it can get quite bouncy in there.

Even the Sierra crest is a "straight line of peaks between you and where you're trying to get." The really high peaks are localized within a couple of miles. It's less than 50 all the way across, counting the moderate terrain (which is easily overflown, but not very hospitable for emergency landings in most places).

If it will make you more comfy, I can go up with you over the Santa Cruz or Diablo ranges. But I'm not right seat qualified (and not an instructor), so you'll have to land the plane. I live in the Santa Cruz mountains and know my way around them fairly well.
 
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MAKG1 said:
That's what it's like over there, too. Near mountains, very flat.

Even the Sierra crest is a "straight line of peaks between you and where you're trying to get." The really high peaks are localized within a couple of miles. It's less than 50 all the way across, counting the moderate terrain (which is easily overflown, but not very hospitable for emergency landings in most places).

If it will make you more comfy, I can go up with you over the Santa Cruz or Diablo ranges. But I'm not right seat qualified (and not an instructor), so you'll have to land the plane. I live in the Santa Cruz mountains and know my way around them fairly well.
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Thanks for the offer! I think I'm good right now. I just wanted to check in to see if there's anything I'm missing about these shorter mountains, or if they are as safe as they appear to be to me. :)
 
joycem137 said:
Thanks for the offer! I think I'm good right now. I just wanted to check in to see if there's anything I'm missing about these shorter mountains, or if they are as safe as they appear to be to me. :)
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It's worth checking. I think you've seen all the pieces, though possibly in a different order.

The first rule about sightseeing (or any other type of flying, really) is to fly the plane first. It's really easy to focus on a photo or circling something interesting, focusing on the scenery rather than the flight, as your airspeed decays or someone blasts up the valley in the opposite direction. This is where your risks are, not in flying up the Salinas Valley.

And, flight following doesn't always work so well in the mountains, especially close to the terrain (I get dropped every bleepin' time I fly over the Sierra). But it works really nice in the Salinas Valley.
 
As a new Colorado mountain pilot and former Oklahoma resident the mountains scared me to death. I wouldn't bring my plane from Oklahoma until I took the Colorado Pilots Association mountain flying course.

Now only after 15 hours I'm getting very comfortable to flying in the 11k-14k mountains. It just takes a little planning. Watch winds at altitude. Here if 20-25 knots, avoid flying. Always fly where you can turn towards lower terrain. Approach at 45 degrees so you can turn away if needed. Never fly after 12 or 1 in afternoon.

You can try flight following, but its a good time to do the VFR flight plan and give regular position reports along with pilot report.

Just a couple tips. From what your describing go fly high above em and build some confidence. Have fun
 
There is only 1 rule in mountain flying.
1. Be higher than the mountain.

Everything else is just support so you can be higher than the mountain.
 
For starters, get a copy of Mountain Flying Bible by Sparky Imeson. Reading that will make you acquainted with the skills and knowledge that you will have to acquire in order to do it safely. It's not rocket surgery, but there are definitely things that you have to be aware of and take into consideration. Read up on and get really proficient with things like density altitude, takeoff and climb performance calculations. Also, be a bit skeptical about those numbers, they will probably be a bit "optimistic". Then, get a good mountain checkout by somebody who knows what s/he is doing.
 
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Shepherd said:
There is only 1 rule in mountain flying.
1. Stay higher than the mountain.

Everything else is just support so you can stay higher than the mountain.
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FTFY.

You're in a bad place if you're at 1000 AGL in a narrow pass in a 2000 FPM downdraft. You're still above the mountain, but that may or may not persist for very long. You're also in a bad place in IMC in a mountain pass.

But we're not talking about real mountain flying here. A 172 is capable of flying nearly two miles above the peaks.
 
MAKG1 said:
That's what it's like over there, too. Near mountains, very flat.

Sunol's not that flat. It's 1000 feet above the surrounding valleys, hemmed in by overlying Class B. And it can get quite bouncy in there.

Even the Sierra crest is a "straight line of peaks between you and where you're trying to get." The really high peaks are localized within a couple of miles. It's less than 50 all the way across, counting the moderate terrain (which is easily overflown, but not very hospitable for emergency landings in most places).

If it will make you more comfy, I can go up with you over the Santa Cruz or Diablo ranges. But I'm not right seat qualified (and not an instructor), so you'll have to land the plane. I live in the Santa Cruz mountains and know my way around them fairly well.
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Right seat qualified? Some new rating or endorsement?

Bob Gardner
 
If you're truly doing mountain flying, sometimes you are going to be over terrain that just is not hospitable to an emergency landing. The trick is to plan your route so you minimize inhospitable terrain.

A long time ago, I decided to take a flight to Mammoth from the Bay Area. I went direct because I could - turbocharged airplane. It occurred to me as I flew over the desolation wilderness, "this is stupid." if something went South, there was no way a landing would be survivable in the midst of those sheer vertical granite pinnacles reaching to 12K. I've always flown that route since using the passes, like Mammoth Pass, even though it is a bit of a dogleg, which guarantees me to be within gliding distance of a survivable landing spot for pretty much the whole trip.
 
Desolation Wilderness is really far out of the way. It's just southwest of Tahoe.

You mean the Ansel Adams Wilderness? You have to go through there to go through Mammoth Pass. But the route from Tuolumne Meadows has a line of campgrounds and lodges west of the Ritters. There is lower terrain along V230, but it's still roadless and VERY remote. Really, really beautiful, though. Hard to imagine.

If you're worried about ever being found again, Tioga Pass isn't that bad. Very squishy surfaces in early summer, but it's fairly flat and there is a road up there. In the winter or early spring, that might as well be Mars -- there are NO good Sierra crossings between I-80 and CA-58.
 
Skylane81E said:
No, if I NEED to turn around I don't want to be on the good side, as when I turn my situation will only get worse
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I'm a student, so this isn't worth much, but...

I just read an article about mountain/canyon flying that was advocating that one should fly on the downwind/updraft side such that the upward moving wind tends to lift you upward rather than push you down into terrain and also so that, if you need to turn away from the mountain/canyon wall, you are turning into the wind, your ground speed is slower than if it were the other way around, and your turn radius is smaller.

Does that sound right? And, if so, which side is actually the good side?

I have been looking for the article to share in this thread, but so far can't find it.
 
Yup. Generally, the "good side" is the downwind side. Air flows over the upwind side and sinks into the canyon, then rises on the downwind side. At least in an ideal world. It may be quite turbulent if it's really windy or if the canyon walls are really steep, and you may have to go feeling. Not good; this is why high winds in a high pass are considered a bad situation.

If you can get over the peaks, the whole effect gets lessened -- usually. This may or may not be an option, for a variety of reasons. A 172 isn't going to top a 13000 foot peak unless it's real cold.

When you start to get well above sea level, you start to really notice the rising and sinking air. It's quite significant. Your airplane may not climb all that fast, but if you find rising air, up it goes as if by magic. If you find sinking air, you get out of it. If you fight it, you can lose airspeed in a hurry and your CHT goes up.

There is a separate rule that says to fly the right side of a canyon, in case of opposing traffic. It's a judgment call as to which is more significant. Ideally, you do this in light wind, so the traffic is the bigger concern.
 
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Frankly I've seen both. All canyons are not created equal and wind sometimes blows from odd directions.

If one side doesn't work, use escape plan, clean shorts, poke carefully at other side, find it worse, clean shorts again, land at airport behind you and wait for better weather.

There's no hard rules other than (as someone pointed out), "Don't hit the mountain", and secondarily where the rubber hits the road on the primary rule,, "Always leave yourself an 'out'."

Lots of folks have pointed out Sparky's book. Keep in mind that he still died doing it. I miss Sparky. And I've read his book multiple times. One is signed by him.

A CFI friend recalls a day when everything was "perfect" except for medium to light winds, and his Mountain Flying student and he, got to see just how close one could get the belly of a Cessna to the rocks at Hagerman Pass here in CO.

45 entry as long as you can (you eventually run out of room to not be almost 90 degrees head on right near the top), 1000' AGL, looked fine...

Committed to the pass crossing, they were slammed downward at the critical crossing point. 1000' turned into 100' in the blink of an eye. If they'd only done 800' AGL they'd be dead.

The road crosses Hagerman at 11,925' MSL. Due to terrain, you can't follow the road as easily as you can follow the power lines, which are higher. It's the pass high performance aircraft typically fly over to go from KASE to KLXV.

Low horsepower aircraft shouldn't even attempt it. Ever. Climbing out of KASE Westward (wrong direction to get to Hagerman) on a. 70F+ day in my Skylane with two aboard and half tanks, it's a maximum performance climb at Vy all the way down-valley, turn to cross the ridgeline to the north and reverse course to the East up the north side of that ridgeline and continue maximum performance climb all the way to Hagerman.

Takes almost 45 minutes at those speeds. Engine cooling is a significant problem also, and a level off and then orbit/shuttle climb in the valley, may be required for engine temps to remain reasonable.

A T182T will do it in 30 minutes flat. No cooling issues, much more power available and airflow through the cowl.
 
joycem137 said:
If we want to land at an airport above 3500 MSL, we need to get a mountain flying checkout. No requirements on *where* you can fly. Just where you can land.
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That makes some sense. The last rental restrictions I saw here at one club were for no landings on less than 2500' runway, and it had to be paved. No MSL data.

Alternate Air Inc club at BFI requires only FAA currency and following all regs the last I checked.
 
Skylane81E said:
No, if I NEED to turn around I don't want to be on the good side, as when I turn my situation will only get worse
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I fly the Rockies all year round and avoid the upwind side of valley whenever possible. Strong rotor, wave, downdrafts, are super common. I guess we'll just have to disagree on this one.
 
joycem137 said:
If we want to land at an airport above 3500 MSL, we need to get a mountain flying checkout. No requirements on *where* you can fly. Just where you can land.
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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.
 
EdFred said:
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.
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It's the DA ops they're considering.
 
Dave Krall CFII said:
It's the DA ops they're considering.
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Yes. Flatlanders don't know to lean for best power at run-up above 5000 feet DA. That's going to be a factor even when there are no mountains, such as in Denver. Heck, half the students at PAO can't figure out that you should lean aggressively for ground ops. I have to clear fouled spark plugs almost every flight.

There are plenty of mountains in California, but not a lot of high altitude airports.

I'm a bit surprised they don't require actual mountain training -- just one landing at an airport at moderate altitude. But the actual training is a whole new world, and is very much worth it. Not necessarily from KPAO -- the real mountains are far away, and flying an hour each way over the Central Valley is both useless and expensive. And I have a beef with at least some of the PAO instructors, as they make silly comments like "it's unsafe to fly in the Sierra with under 200 HP." Never mind that there are 160 HP 172s based at Lake Tahoe (like the 172M and N at Sierra Aviation in Truckee), and people train in them. There are definitely extra things to think about, but that's the point of the training. I'll suggest a lot more benefit will come from going somewhere in or much nearer the mountains and training locally.
 
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