Los Angeles to Mammoth Lakes, CA - Thoughts?

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AA5Bman

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He who ironically no longer flies an AA5B
Curious if anyone can share some experience flying in and around Mammoth Lakes, CA?

I'm based in LA and have always wanted to fly to Mammoth to ski, but am nervous about the winds and weather. Most of the route is straight up the Owens valley - more a gorge than a valley - running north-south on the lee side of the southern sierra and it's endless 14,000' peaks. I know the wind just whips up there - reports of 100+ mph at ridge-top are not at all uncommon. To make matters worse, visibility and precipitation at KMMH is nothing if not unpredictable.

The weather looks pretty mild for the holiday weekend and I'm thinking about making the trip Thursday through Sunday. If anyone has some thoughts or experience to share, I'd sure appreciate it!

Thanks in advance,

MB
 
Good route fun flight. MMH is in a big bowl that is a piece of cake VFR and a challenge IFR.

When you fly into a place like Mammoth or Aspen you see why IFR terrain clearance is se the way it is.

Joe
 
Curious if you've ever made the flight in the winter?

Mammoth is funny - when you drive up there, you go up past Crowley and the airport, nice beautiful VFR weather. Then I swear, every time, as soon as you turn off of 395 just a mile or so away - BAM - blizzard. Makes me nervous.
 
I've flown over and in the Owens Valley a bit. It was never dramatic, except for one time when the surface winds on the mountains were at 22 knots. The other few times, winds reported there were around 12 knots, and it was quite smooth.

I don't think you'll have a problem as long as it's a nice, stable weather day and the winds are light. If they aren't light or if the weather isn't somewhat stable, I personally wouldn't go. The turbulence there can be .... quite extreme :p
 
I'm no expert, that is for sure, but I have found throughout my life in other things, if you have to ask the question, you probably are not ready. If you go, you should have a back-up plan besides flying to get you back. Mountain weather can turn fast.

John
 
AA5Bman said:
Curious if anyone can share some experience flying in and around Mammoth Lakes, CA?

Thanks in advance,

MB
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When I lived in San Diego a lifetime ago, I made that trip several times in a C-120, a C-170, and a C-172. Summer & Winter. Bakersfield, hang an east, over Tehachapi, miss Edwards hot zone, Mojave, up the valley to Bishop, hang a 45 left up 395. Nice airport, at least it was 35 years ago.

If you ever go up in the summer, the glacier at the south end of Convict Lake is gorgeous.

Asking questions is the mark of a good pilot, not one who should not be making the trip. I have not checked the forecast. Any clues what the 72 hour progs show?

Just don't box yourself into "I have to be home by Sunday afternoon" gethomeitis. There is widely scattered aluminum in the Sierra with folks like that.

Jim
 
I would go. Take an inventory of yourself, your airplane. You should have already been watching the weather looking for patterns and trends. It's not too late.

You are PIC, you feel up to it? It looks like it may get iffy right now in the rest of CA. There is some weather on the way. But the east side is a different region...if you're okay with winds and know when to duck out before the weather insidiously creeps in around you, you'll do well. Be determined but open to alternate plans.

I ask a lot of questions...even basic stuff I already know. I won't know everything in every way. Nothing wrong with asking. I agree with the point John Baker is making but I disagree with the premise that to ask means you aren't ready.

Be safe, have fun, learn stuff.
 
Thanks guys, great advice. I felt a little prickly with John's comment "if you ask you're not ready", but I get where he's coming from. I frequently ask questions that seem unwarranted in retrospect.

I'll keep watching the forecast and will have an alternate in mind if I do go.
 
OK, I screwed up, you guys are right, asking questions when it comes to flying does make a whole lot of sense. I guess what got me going in that direction was that he said he was nervous about the winds and weather. Then again, when it comes to mountain flying, even small ones, you can find yourself in a whole lot of trouble fast on the lee side, you should be nervous. You can be a huge distance away, and still get caught in mountain waves. Again, if you can get altitude, even that is not a concern.

John
 
John Baker said:
You can be a huge distance away, and still get caught in mountain waves. Again, if you can get altitude, even that is not a concern.
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There's a big "but" with that, though. Mountain waves can reach up quite a ways. I remember an accident from that general area just a few months ago where a twin was brought down that was flying at 18,000' or similar. It's not unheard of that mountain waves can go up to far above the altitude of the mountain chain....
 
Just for kicks, I thought I would share this with you guys. This is why it makes me nervous (and yes, those mountains really do go all the way up to 14,000'. Keep in mind that I'll pass Mt. Whitney, the highest mountain in the lower 48 on my left):
Mammoth.jpg
 
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AA5Bman said:
Just for kicks, I thought I would share this with you guys. This is why it makes me nervous (and yes, those mountains really do go all the way up to 114,000'. Keep in mind that I'll pass Mt. Whitney, the highest mountain in the lower 48 on my left):
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I recommend the flight, weather permitting, it is beautiful. This was taken last summer. Mt Whitney is the tall one :)
 

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This time of year it is anyone's guess what the wx will be doing more than a couple days intot he future. Especially along that route. I am familiar with that route and the terrain out there.

With that said, I think you may be surprised that the winds will be out of the NE. Warm, upslope east to west. I think the key is what, if any, highs dominate the area. Watch the baro. Staying at minimum altitudes could be the best option. And do not let overconcern to avoid Edwards SUA push you towards the mountains if the wx should dictate that. Don't be a Liddle.

In situations like that I adopt the attitude that this will be consecutive short flights rather than one longer flight with perhaps a fuel/pee stop. That way I am already primed to turn away if I started to feel uncomfortable. Keep poking the edges of comfort but be ready to make for the fall back position. And even that could involve a change. At any given point continue to ask yourself, Is this a good idea? Yes/No?

I think GA pilots get in trouble when they insist on that "airline attitude". You aren't a scheduled flight that 'must' keep a schedule.
 
Great depiction.. if it's windy.. stay above the rotor.. and farther west towards the Inyo's and Whites.. that's the ridge west of Lone Pine to Bishop.. then cut down into Mammoth. On the west side of the valley the "wave" should be going up.. so you may have power back.. nose down and still be climbing... and if that is what you find.. keep an eye our for white gliders doing the same thing... but they will be closer to 17,500.
 
In a Cheetah/Tiger he doesn't have that choice.

He needs to choose a day where the winds aloft at 12,000 are <30 mph. He only has 90 hp available at 12,000 feet, remember. In a Cheetah, only 75 -80 hp. Service ceiling in about 12K, too.

If the wind is up his TEETH will regret it. It's pretty jarring.
 
BillTIZ said:
Great depiction.. if it's windy.. stay above the rotor.. and farther west towards the Inyo's and Whites.. that's the ridge west of Lone Pine to Bishop.. then cut down into Mammoth. On the west side of the valley the "wave" should be going up.. so you may have power back.. nose down and still be climbing... and if that is what you find.. keep an eye our for white gliders doing the same thing... but they will be closer to 17,500.
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I think you mean east?
 
An interesting question to me, as I've just finished reading about the Sierra Wave Project (Exploring the Monster by Robt. Whelan), where extensive study was made of the effects of the terrain, etc. on air in the vicinity. The Owens Valley was carefully chosen because the wind does incredible things around there.

A pilot named Harland Ross is said to have "discovered" this when he found himself climbing from 14,000 to 18,000 in a stock Cessna 140 near Bridgeport. He later went on to try to replicate that, and did even better- from 6,000 to 23,500. In eight minutes. In a C-140. And waaay over a C-140's service ceiling. Later on, he coached a student through a flight in that same plane where he secured the engine and had the student fly the wave between 11,500 and 17,500, soaring all the way from Bishop to Big Pine and back. There had also been reports by B-29 crews of extremely powerful up and down drafts in that area- enough to rattle a B-29 crew, 'nuff said.

In addition to these flights and many SWP glider flights into the stratosphere, including one which encountered a rotor that simply tore the glider apart, local conditions allowed for stuff like Ross' friend and colleague, Bob Symons, shutting down and feathering both engines on a Lockheed P-38 and soaring it, between 13,000 and 31,000 feet, for over an hour.

Be sure to look at the first picture (taken on that flight) that accompanies the article- if you don't know what it shows, find out before you fly through there. :D

http://www.inyokernairport.com/soaring_at_iyk/soaring_at_iyk.html



Sure, this is upper-air stuff, very strong winds, etc... but on the days when the "Bishop Wave", with its frightful rotor, was strongest during the days of the SWP, the surface winds were also pretty damn strong, as were the winds just below the peaks. You are wise to be cautious, I think. But there's no reason it can't be flown safely, if conditions are right and you know what's going on and how to work with it.

I've never flown close to the lee of anything that tall, nor have I had much experience with wave or rotor phenomena myself, but from what I've seen and heard, I'd recommend staying away from the center of that valley if the wind is blowing. And if you learn more before going there, you might save a lot of fuel if there is a good wave... :D
 
bbchien said:
He needs to choose a day where the winds aloft at 12,000 are <30 mph.
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Bingeaux! Having safe and stable winds aloft is the key. I did the flight from the LA Basin to Mammoth a few times in an Archer when we were living out there. It's a beautiful flight - well worth it when weather permits. If you make the flight up the Owens Valley at 8,500 you arrive at Mammoth a couple hundred feet above pattern altitude. As with all GA vacations, you need a Plan B.
 
Hey guys (and gals),

I just thought I'd update this post with some pictures and comments - I did end up making the LA to Mammoth flight this weekend, and it was awesome!

I have to tell you, though, it really was intimidating. Entering the Owens from the south is frankly a little bit scary. At 10,500 on the way up, we were still looking up - significantly up, that is - to see the peaks that line either side of the valley. I didn't realize it, but the Whites, which are the mountains on the east side of the valley, are nearly as big as the eastern sierra - with some 14,000'ers of their own...

The winds were forecasted at 12,500 to be something like 290@25, but they were more like 045@25, exactly as Richard said - a quartering right headwind, upslope east to west. This was a total surprise to me, and it meant that to stay on the "rising air" side of the valley was to stay on the west side of the valley, and pass directly under Mt. Whitney, etc.

With those winds, there were some lenticulars forming, and that was pretty dang intimidating. You could see the lenticulars forming on the far side of the Whites to the east, and just a couple on the upslope side of the Sierra (you'll see some in the pictures). I have my glider license, so I figured we'd just plod along like a glider until we didn't like it anymore in which case we'd turn back. We also had some pireps of planes at our altitude flying the same route who reported no significant turbulence, which was very encouraging. They were reporting only light chop, which is exactly what we encountered. We did get a couple of good 400 fpm updrafts, but no downdrafts on our side of the valley whatsoever. Landing at Mammoth, the air was smooth as butter.

The return trip was less eventful, with high pressure, some very high cirrus, and low winds. The only thing worthy of reporting was that the wind would swirl - first it'd be 045@10, then 180@7 then 290@9 - weird, but not surprising.

The only real problem we had was starting the Tiger at Mammoth yesterday at 35 degrees OAT - anyone have any tips? I thought we weren't going to get her going...

I've posted some pictures below, but please feel free to browse here for more: http://picasaweb.google.com/mikebjerke/MammothViaTiger#

Northbound, in the Owens Valley:
DSC_0080.JPG


The desert near Mohave:
DSC_0024.JPG


Ominous weather:
DSC_0114.JPG


Serious mountains:
DSC_0108.JPG


DSC_0083.JPG


DSC_0091.JPG


Landing at KMMH:
DSC_0133.JPG
 
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The skiing was fine - blue skies, "packed powder" (now there's a misnomer), good groomers - but it wasn't really my cup 'o tea. We get spoiled at Mammoth and if there's not 12+" of powder I have a hard time getting motivated. The weekend was really neat, good skiing or not.

This is more my style:
P1000332.JPG
 
Nice pics and glad you had a safe flight. If the mid level winds were out of the west and you flew that present course in pic#1 that clipboard would have been pitched right through the windscreen.:yikes::yesnod:.

My time tested reasoning to flying around mountians is.

If there is a lens cloud anywhere in sight treat the whole flight as suspect and be ready to turn away from those ol 'rock monsters'.

Ben
Jackson Hole Wy.
ya, we have some pretty impressive peaks here too.
 
AA5Bman said:
The only real problem we had was starting the Tiger at Mammoth yesterday at 35 degrees OAT - anyone have any tips? I thought we weren't going to get her going...
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Preheat.. and primer..
35F is not too bad for starting.. it's been cold soaked for a couple of days.. keep the rpms low until the oil warms.. no taxi, no rpm over 800-1000 until at least 70F oil on the temp (GEM is great).

We do not have preheat for the Pawnee, but we start normally with temps in the low 30s. Pleanty of primer.. and it starts right up in about 3-4 blades.

Keep the RPM low, the Pawnee does not have a GEM, just oil temp and oil pressure. No high engine run mag checks until the oil temp is at least into the 100F range.. and then watch the oil pressure. No more RPM then what will run the oil temp to red line.

I keep the RPMs about 10# below redline oil pressure during the warm up. For the Pawnee, (O-540) oil temp needs to be above 120F before take off, and we are light enough that 2300RPM will be fine for take off to get the oil temps up higher without going over red line on pressure.. as the temp comes up, the pressure will go down until full power can be achieved with normal oil pressures.

Then we are ready to start towing.
We have two oil coolers for summer time operations. One is covered for winter operations. We normally do not see oil temperature much above 180F on really cold days. Summer time (110F OAT) we are able to keep our oil temp below 205F with both coolers working.

For your Tiger.. you'll want the oil warm enough for full power without red line oil pressure before take off.

Great pictures going up the Owen's Valley. The White's and Inyo range can be really busy if you see Lenticulars or any time during the summer.
 
Glad to hear you made the flight, I was hoping you would. Did I miss that you previously mentioned you hold a glider rating? To me, that seems pretty important information.

Anyway, those lenticulars don't imply "ominous". Learn to understand the sky. The language is in the clouds. Those are some very awesome pictures. Just those pics are well worth the endeavor.
 
Yeah, I guess I should've mentioned that I have my glider rating. That said, I've never flow gliders in the Owens, although it probably does make me a little more aware of winds I suppose. Or maybe it just makes me more aware of how dangerous they can be!

Richard - you predicted the winds out of the northeast. How'd you know and how would you read the forecast to know to expect that?
 
AA5Bman said:
Yeah, I guess I should've mentioned that I have my glider rating. That said, I've never flow gliders in the Owens, although it probably does make me a little more aware of winds I suppose. Or maybe it just makes me more aware of how dangerous they can be!

Richard - you predicted the winds out of the northeast. How'd you know and how would you read the forecast to know to expect that?
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Good ol 4 panel prog chart. That plus visible moisture sat image for final confirmation. 'course, I also watch the weather every day looking for trends.
 
Hmmm... you just mean you saw H pressure sitting to the northeast and figured H pressure wind goes counterclockwise, basically, right?

The reason I ask is that I also saw the H pressure sitting up there, but the forecasts for winds aloft and at KBIH and KMMH were all for wind out of the 290 degree area, which is the opposite (?).
 
AA5Bman said:
Hmmm... you just mean you saw H pressure sitting to the northeast and figured H pressure wind goes counterclockwise, basically, right?

The reason I ask is that I also saw the H pressure sitting up there, but the forecasts for winds aloft and at KBIH and KMMH were all for wind out of the 290 degree area, which is the opposite (?).
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Hmmm.. High pressure will circulate ' CLOCKWISE'. At least it does here in Wyoming. California has always been different though.:frown2::yesnod:
 
Sorry, that's what I meant to say. I re-read that and tried to edit, but it looks like I forgot.

Yes -- clockwise. East / west, clockwise / counterclockwise - who keeps track anymore?
 
AA5Bman said:
Hmmm... you just mean you saw H pressure sitting to the northeast and figured H pressure wind goes counterclockwise, basically, right?

The reason I ask is that I also saw the H pressure sitting up there, but the forecasts for winds aloft and at KBIH and KMMH were all for wind out of the 290 degree area, which is the opposite (?).
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No. They teach about rotation of the earth, uneven heating, H & L, etc. That is too elementary, that's just the ABCs of the matter. Think of the big picture. The big dogs are constantly jostling for position. I saw two H fighting over an isobaric dog bone to the NE. A weak L, soon to be occluded, to the N shut the gate to any new dog on the block. It was a squeeze play to the S/SW.

I think pilots should just forget about the labels and start thinking in terms of energy. Once they come to understand that, then they can go back and begin to understand what the labels mean.

EDIT: I still don't have a firm grasp on the wind patterns of the eastern portions of the LA basin (EMT-->RAL and FUL<-->SNA). That area gives me the fits. Sometimes it seems like a convergence zone, sometimes not. Even in times of similar wx patterns. Sea surface temps don't seem to be provide the answer. Perhaps the answer is in the mid-levels or higher.)
 
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