SAC to LA

cocolos

cocolos

Pre-takeoff checklist
Joined
Jul 4, 2012
Messages
468
Location
Davis, CA
Display Name
Display name:
cocolos
I was planning on doing a trip from the Sacramento area to the LA Area more specifically to KPOC. What would be the best route? In a 152. I see I might have to go over San Garbriel Mountains. Would I need some Mountain flying lessons? Or would I just go around?

Thanks!
 
South to the Gorman/Tejon Pass. That route can be flown safely at 6,000' (or even a bit less, pass is at about 4,300', but high terrain surrounds it). Lake Hughes is a bit more direct, but you'd want to be at least at 7,000 for that route. If it's windy, there can be serious downdrafts anywhere in that area, so keep in mind a 152 isn't going to climb out of serious downdraft.

Jeff
 
You can follow 99 and 5 all the way down. Terrain is not too bad.

AVOID if the wind is gusting greater than 30 knots at the peaks. Think twice if it's greater than 20. It's worse if wind is blowing across a ridge (especially a headwind), rather than along it; this is fortunately unlikely for the transverse ranges, but it's possible. http://graphical.weather.gov.

I would not recommend flying between the peaks over the transverse ranges. Clear the highest terrain, and do so early.

Some mountain training wouldn't hurt, but it's not so critical, as the mountains aren't that high and you aren't planning high density altitude landings or takeoffs.
 
Jeff Oslick said:
South to the Gorman/Tejon Pass. That route can be flown safely at 6,000' (or even a bit less, pass is at about 4,300', but high terrain surrounds it). Lake Hughes is a bit more direct, but you'd want to be at least at 7,000 for that route. If it's windy, there can be serious downdrafts anywhere in that area, so keep in mind a 152 isn't going to climb out of serious downdraft.

Jeff
Click to expand...

I have done this route a few times in my Cherokee and have experienced the downdrafts. In a low powered plane you can't out climb them, so get some altitude. +1 on the no go, if over 30 KTS.
 
Well, you -can- manage 20-30 knot winds over the low passes if you can make it to 10K or higher...
 
cocolos said:
How would the 172 help? Would I just go over the mountains with it?
Click to expand...

Yup. A 172 can cruise at 9500 or 10500 feet without too much trouble. BTDT. It should be able to go even higher, dependent on temperature up there (service ceiling is 14000 density altitude). That's much more altitude than you need for the problem at hand.

It still can be quite turbulent even at those altitudes above the mountains when the wind is blowing strongly. But when you're a mile above the terrain, there is a lot more margin to avoid it. Then, the only things you need to avoid are Va, Vs, and your own barf. A 172 lightly loaded at Va will be slow. 90 KIAS solo with full fuel, down to 80 with empty fuel (check the POH -- there is a little variation).

At the high altitudes, you'll need to climb close to Vy. It's much lower at high altitude than at sea level (but always higher than the sea level Vx). Watch your climb rate and adjust accordingly. You will be cruising at full throttle in the absence of turbulence, so a cruise-speed climb is obviously impossible.
 
Last edited:
You CAN do GMN DARTS POC at 5500 which still would take a while to climb to in a 152. What others have said about up and down drafts are a significant issue in a 152. Going around can have some of the same issues since the path around is over PRB and then essentially GVO KWANG CMA VNY DARTS at 5500 - but you still need to get to PRB and that might require some effort with some of the same issues overflying some mountainous terrain on the coastal range to get there .

If you do it in the winter on a day without santa ana winds blowing you at least eliminate the solar induced winds and updrafts and downdrafts but winds aloft can be higher which can of course create their own updrafts and down drafts. . .

When I go to BFL in my Comanche I NEVER come back over the mountains at even 7500 - 9500 gives me a smooth ride and comfortable terrain clearance - and there are times near GMN I'm STILL see some bumps. Those mountains around you rise to 8000 feet so putting through the pass at 5500 with the mountains all around you is rather uncomfortable visually and NOT something to do at night.
 
I can drive the PRB route in a car barely breaking 1000 feet. Altitude should be much less of an issue. But it's quite a bit longer -- you'll need to overfly the Bay Area if mountain avoidance is an issue. This can be done with sea level terrain from Sacramento if you fly over the American River. Follow 101 from San Jose southward.

A risk you will get with that route is coastal IMC. You can fly over the clouds (assuming you're not a student pilot), but it means you can't see landmarks. Paso Robles is likely fine, but Salinas, Pismo, Santa Barbara, and so on may not be.

Salinas Valley (and the Bay Area) is plenty wide, but if you're flying below the western peaks (around 4000-5000 feet), it's going to be bumpy all the way down if there is even a modest wind.
 
MAKG1 said:
Yup. A 172 can cruise at 9500 or 10500 feet without too much trouble. BTDT. It should be able to go even higher, dependent on temperature up there (service ceiling is 14000 density altitude). That's much more altitude than you need for the problem at hand.

It still can be quite turbulent even at those altitudes above the mountains when the wind is blowing strongly. But when you're a mile above the terrain, there is a lot more margin to avoid it. Then, the only things you need to avoid are Va, Vs, and your own barf. A 172 lightly loaded at Va will be slow. 90 KIAS solo with full fuel, down to 80 with empty fuel (check the POH -- there is a little variation).

At the high altitudes, you'll need to climb close to Vy. It's much lower at high altitude than at sea level (but always higher than the sea level Vx). Watch your climb rate and adjust accordingly. You will be cruising at full throttle in the absence of turbulence, so a cruise-speed climb is obviously impossible.
Click to expand...

I might just get checked out in a 172 to keep it safe. Would the same route suffice with a 172? or direct?
 
Without mountain training, I wouldn't suggest blasting straight over the San Gabriels, especially near Pomona. Wrightwood is over 10,000 feet.

I'd suggest I-5 all the way into the San Fernando Valley, overfly Burbank Class C and El Monte Class D. With flight following the whole way. SoCal Approach seems to be rather cooperative.

An alternative would be to cross the San Gabriels at Cajon Pass (I-15). You're virtually guaranteed some leeward turbulence from Wrightwood at some point if you go there.
 
OK - MAKG - a few comments - I"ve come through Cajon at 7500 and gone over at 6500 and seen no turbulence - depends on the winds in the desert . . . I've landed at Mojave with the winds CALM . . . perhaps not a common occurrence and have been there several times with winds under 8 knots.

I don't think there are many people who go over the San Gabriels from Pomona north - you have Mt Baldy to 10k and few 8k peaks here and there - other than airliners over FL180 heading over my house to HEC and DAG. But the route you suggest is the most common way out of the basin north through the central valley - coming south from BFL you simply do GMN DARTS KPOC . . .

I would NOT take a 152 over the mountains anywhere - not that folks don't do it but power is the key to safe ops . . .
 
I've been through Cajon calm as well.

But gotten bounced around NORTH of Wrightwood (toward Hesperia) on an otherwise calm day at 9500 feet (there was a moderate south wind at altitude).

Of course, if there is calm wind at altitude and calm wind on the ground, mechanical turbulence doesn't have a way to form. Thermal turbulence might, but that's an issue over the desert as well.

This time of year, the desert winds are still blowing (over 20 knots peak at the surface this week at PMD), though it's decreasing. It will get better as it gets cooler. It's also better in the morning, as you know.

Another reason to avoid Cajon in a 152 is how you need to get there from northern California. Tehachapi Pass is one of the oldest wind farms for a reason, and I've seen spectacular mountain waves form over California City (fortunately from the ground). Gorman, or over the aqueduct tunnel, looks to be much better, but it's not shorter than just flying on down I-5.
 
Last edited:
cocolos said:
Looks like I-5 with a 172 it is!
Click to expand...

perfect. The route on a sectional looks like GMN DARTS KPOC. I am based at KPOC so let me know if you need any local specific information. You can do it at 7500 . . . it will look uncomfortable from a terrain in the windscreen perspective but it is doable. 9500 will look great.

A FREE bit of advice coming into POC from DARTS. . . .

There is very busy practice area over the Santa Fe Dam Recreation Area - VERY BUSY. But most of the CFI's try to keep the airplanes at 3500 and below there. You want to DELAY your descent in the 172 so that you pass that area at 4000 and above and have your head on a swivel. This generally means - at least for me - about a 700fpm rate of descent and holding the descent off until that point -

If you are at 7500, POC's traffic pattern is at 2200 - so - thats 5300' of elevation loss @ 700fpm or about 7 min out . .. .

You also have TWO choices into POC - 26L and R. Since you will be transient you'l want to park in transient parking which is on the south side of the field. So look at 26L as the preferred runway - which means you may want to do GMN DARTS V186 ITSME - the last fix - ITSME - is just to the west and a little bit south of POC which means if you hit that fix you can turn about 20 degrees left right onto downwind - plus - it'll avoid the practice area even a little bit more - just remember that ITSME is basically over EMT so you need to be in the descent there - not at pattern altitude yet!!
 
Last edited:
comanchepilot said:
perfect. The route on a sectional looks like GMN DARTS KPOC. I am based at KPOC so let me know if you need any local specific information. You can do it at 7500 . . . it will look uncomfortable from a terrain in the windscreen perspective but it is doable. 9500 will look great.

A FREE bit of advice coming into POC from DARTS. . . .

There is very busy practice area over the Santa Fe Dam Recreation Area - VERY BUSY. But most of the CFI's try to keep the airplanes at 3500 and below there. You want to DELAY your descent in the 172 so that you pass that area at 4000 and above and have your head on a swivel. This generally means - at least for me - about a 700fpm rate of descent and holding the descent off until that point -

If you are at 7500, POC's traffic pattern is at 2200 - so - thats 5300' of elevation loss @ 700fpm or about 7 min out . .. .

You also have TWO choices into POC - 26L and R. Since you will be transient you'l want to park in transient parking which is on the south side of the field. So look at 26L as the preferred runway - which means you may want to do GMN DARTS V186 ITSME - the last fix - ITSME - is just to the west and a little bit south of POC which means if you hit that fix you can turn about 20 degrees left right onto downwind - plus - it'll avoid the practice area even a little bit more - just remember that ITSME is basically over EMT so you need to be in the descent there - not at pattern altitude yet!!
Click to expand...

Sweet Thanks!
 
Not sure if I should use a new thread but what kind of oxygen systems do you use? if any.
 
cocolos said:
Not sure if I should use a new thread but what kind of oxygen systems do you use? if any.
Click to expand...

Above 12,500 - a 24 liter bottle w/cannula. At the altitudes discussed in this thread - none. I have started using O2 at lower altitudes at night and it does help.
 
Yes, I've been up to 10,500 with no oxygen. I do have a pulse-ox handy to monitor. I've descended once because a passenger didn't feel well, but otherwise, it's been very uneventful.
 
You must log in or register to reply here.
Back
Top