Flight planning brain trust question

Timbeck2

Final Approach
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Timbeck2
Tucson (KTUS) to Rocky Mountain Metro (KBJC)

Never been there, just in the preliminary stage of planning it out. Cherokee 140 and 1 planned fuel stop along the way. Not the most experienced pilot so I'm asking you guys with multiple log books, or big brains how would you fly it VFR and when would be the best time of year?
 
I have flown essentially the reverse trip, both times in my 180 HP Cardinal. Once in June and once in October.

The June trip involved flying underneath developing cumulus in the late morning and staying well away from some very powerful TS to the east. Went south to Pueblo, them through La Veta Pass and south to Los Alamos. Over the pass near 14k to maintain fair clearance and allowance for winds.

October trip was in fairly calm weather. Flew through Monarch Pass over to Blake CO for very attractively priced fuel and some lunch. Also at about 14k over the pass. That felt safer to me than La Veta with a wider pass and road below. After Blake south to 4 corners, Winslow and then home.

Of course the more conservative route is up past Santa Fe and east then through Raton Pass and north over the plains.

I like mountain flight and love the views, but it is less conservative to go through those passes. They now have cameras as well as the AWOS sites, so that helps.
 
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The route depends on your airplane's service ceiling and your own comfort with altitude. I frequently fly from Farmington NM (about 3/5 of the distance on the route from Tucson) to the Denver area VFR crossing the mountains via Wolf Creek Pass then Hayden Pass. This can be done at 12,500 feet, and this is regardless of direction since you are less than 3000 feet AGL. So technically no need for oxygen, although if you live at lower elevation you might want it. If you want to put something on the GPS use KPSO Pagosa Springs arpt to Gorje intersection, then direct to BJC and that will approximate the route. If you have ADS-B Denver Center will see you, but you will not have good radio contact the whole time.

If you don't want to go that high, head from TUS toward Albuquerque. Cross the mountains between Albuquerque and Santa Fe, heading toward Las Vegas NM or FTU VOR. Then turn north and parallel the range to the east past Pueblo and CO Springs. You can accomplish that route as low as 9500, although it is not as direct.

The best time of year? Well, anytime you have a day or two to wait out the weather. During the warmer months, you can make the flight almost every day if you depart at 6 am and land by noon. Note I said almost, not every day. Winter you can have good weather for week, then be snowed in for a week. Hard to predict until you are within a couple days. Best guess would be May to June and September to early October.


Jon
 
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4Corners covered it well. I prefer the lower route — especially if there’s any wind aloft. Mechanical turbulence will easily exceed the climb performance of a 140 on his high route. Have had my butt kicked in the 182.

Also KBJC is easy 99% of the time and pure crap if they have high winds up there. If they do, KAPA or even KFTG end up better options or alternates usually. Or even KFNL and drive south. LOL.

Transient tie downs at KBJC use chains for a reason... LOL... worst time is from March (snowiest month) to May (spring winds) but will only be wild about three days (plus whatever for snow removal from whenever the March blizzard happens) out of those months. Conditions won’t be flyable for a day or two during the snowstorms. IFR, wind, and visibility in some combo.
 
Just checked and a Cherokee 140 looks like it has a service ceiling of around 11k. I don’t remember if Tim’s plane is upgraded beyond this. But with a ceiling of 11k, I think the easterly route over Raton Pass (at 7834’) is likely safer.
 
North to I-40, hang a right, east to Albuquerque, hang a left, north to Alamosa (ish), hang a right, over LaVeta pass or other likely pass in that range, hang a left, north the KBJC. Look out for KCOS as they get annoyed if provoked but they are generally sorta good folks. There are various routes from Alamosa to the Denver area...chose wisely. If it’s really windy in Colorado, don’t hang the left at Albuquerque continue past all the mountain type things + another 20 or 30 miles and turn left. Stay out over the plains at least 20 or 30 miles downwind of the big hills. I did the trip from Albuquerque to Denver with 40 to 50 knot winds in the San Louis Valley and it wasn’t a particularly comfortable flight. The aircraft and I survived so I counted that as a successful trip but wouldn’t willingly do it with passengers or in an airplane with less than about 200 hp.
 
Appreciate all you guys. I was just trying to plan out a flight using Skyvector and it dawned on me that I could ask people who've actually flown the trip.

Dr. Steinmetz, sadly although my little 140 has been upgraded in avionics and interior stuff, the engine still only makes 150 hp if I'm lucky. I've had her up to 12.5 but it took a loooooong time to get there. The POH service ceiling is 14.3. I think the POH lies.
 
I think the POH lies
Perhaps a production test aircraft fresh off the assembly line might have done it one and only one time, barely loaded with enough fuel and optimum weather conditions.

This was good enough for the engineers, POH writers, and marketing department
 
With a 140 I'd go more or less:

TUS => SVC => TCS => LVS => 4V1 => PUB => BJC
(adds 100nm vs direct)

Other planes = more direct options.
 
I have a route planned. Anyone know how to screen shot and post from Skyvector? It's pretty close to Eddie Freddie's recommendation.
 
See if this works



Of course it doesn't look like it did.

Edit: Here's a link

https://skyvector.com/?ll=39.026011...KLVS 3706N10452W 3825N10444W 3842N10445W KBJC
 
Perhaps a production test aircraft fresh off the assembly line might have done it one and only one time, barely loaded with enough fuel and optimum weather conditions.

This was good enough for the engineers, POH writers, and marketing department


I first read this as "barely loaded with enough fuel and opium" :eek:
 
Looks good. Once you get north of Colorado Springs, be extremely vigilant for traffic. That corridor between the Denver Class B and the front range mountains can be chock-full of trainers, VFR traffic, etc.
 
Looks good. Once you get north of Colorado Springs, be extremely vigilant for traffic. That corridor between the Denver Class B and the front range mountains can be chock-full of trainers, VFR traffic, etc.
Appreciate it.
 
Looks good. Once you get north of Colorado Springs, be extremely vigilant for traffic. That corridor between the Denver Class B and the front range mountains can be chock-full of trainers, VFR traffic, etc.

Would go a step further, since you’ll have to talk to Springs anyway (I assume, too busy to look at planned route but assuming it goes thru their airspace) just stay on flight following with DEN TRACON. Springs will almost always hand you off anyway.

The area between springs and Den gets crammed full of aircraft due to the rising terrain there and then the west side “VFR corridor” once under the Bravo shelf is always crammed full too.

TRACON will 99.9% of the time vector or ask you to remain west of I-25 and highish to keep you out of the traffic going to and from the west and east practice areas for KAPA on their climbs and descents into and out of there.

West practice area is essentially Chatfield Reservoir and south for a few miles, all altitudes. East practice areas you probably won’t have to deal with if staying west of I-25.

Training radio traffic is on 122.75 but if you’re talking to DEN you won’t need it. And they’ll be using location names that won’t make any sense to a transient anyway...
 
Ahh took quick look @Timbeck2 — Springs almost never lets you go up their west side if they’re busy. Ironic since DEN will want you under the bravo on the west side. So you make a big “zig” around KCOS.

Usually they will want you going nearly right over the top of the little restricted area (strange I know) or very close to it on the southeast side and not turning west until after the airpark.

It’s. Dumb.

But it works better for them.

They keep the KCOS “pattern” over against the mountains and turn airliners over there sometimes.

Of course then you get the “fun” of crossing the KAPA 35R final to cross over to the west side right at the altitudes the jets are at for approach intercepts. About 9000. VFR practice approaches are at 8500 there.

Everybody is squished into 2000’ of vertical space.

In other words... yeah... FF and talk to the TRACON. LOL.
 
North to I-40, hang a right, east to Albuquerque, hang a left, north to Alamosa (ish), hang a right, over LaVeta pass or other likely pass in that range, hang a left, north the KBJC. Look out for KCOS as they get annoyed if provoked but they are generally sorta good folks. There are various routes from Alamosa to the Denver area...chose wisely. If it’s really windy in Colorado, don’t hang the left at Albuquerque continue past all the mountain type things + another 20 or 30 miles and turn left. Stay out over the plains at least 20 or 30 miles downwind of the big hills. I did the trip from Albuquerque to Denver with 40 to 50 knot winds in the San Louis Valley and it wasn’t a particularly comfortable flight. The aircraft and I survived so I counted that as a successful trip but wouldn’t willingly do it with passengers or in an airplane with less than about 200 hp.

 
Sounds like fun........ Something to think about. Storms often start off the coast. Like in the Gulf of Alaska for example. So if you watch those air masses, you can predict a weather window with some accuracy. You want to do this when its enjoyable. So watch the those weather systems, and plan accordingly. I don't know you time, or how much time you have, but hope that thought helps with your planning. I think the Colorado Pilots website has some mountain flying info that could be useful.
 
Remember that the service ceiling is density altitude, not indicated altitude. That little fact has killed many. Anyway, Eddie Freddie's route is good unless it's windy. Go further east of the front range if the winds aloft are in the 40 to 50 knot range (or higher!). Catch the right weather day and you can see the clouds streaming from the peaks...then one begins to understand why the heck it's a good idea to be a long way from the hills. Yes, one can go under some of the terrain induced turbulence, sometimes...sometimes the crap goes to the ground. I've gotten low to get out of crap and other times I've been scared by the winds when driving to a destination after deciding it was too windy to fly. Rotors can go to ground level in some situations and you can see them moving across the prairie grass from the right vantage point.

Plan to fly early in the day. In the summer be out of or away from the hills by about noonish. Maybe earlier. If ya know about skew-Ts it doesn't hurt to look at them. If you don't know about them then learn before venturing into the mountains very often.
 
Appreciate all you guys. I was just trying to plan out a flight using Skyvector and it dawned on me that I could ask people who've actually flown the trip.

Dr. Steinmetz, sadly although my little 140 has been upgraded in avionics and interior stuff, the engine still only makes 150 hp if I'm lucky. I've had her up to 12.5 but it took a loooooong time to get there. The POH service ceiling is 14.3. I think the POH lies.
I owned a 140 with 160HP for 14 years. I had the same experience as you. Look up the weather history the day you were at 12500. Then calculate the density altitude that you were flying in. A cheaters way is to calculate DA on the ground and add the difference at altitude. If it was a warm day I'll bet you were flying close to 14K DA.

High winds aloft often go up or down as well as sideways. If there is a down component you will go down too. I was flying from north-eastern VA to Hilton Head SC with a 35 kt tailwind. I was being pushed up or down several minutes at a time. With a desired altitude 8.5k, I couldn't maintain altitude during the downdraft, but I could at 6.5k. That was over the mostly flat terrain underneath. The mountain winds are more amplified. I'd get some time with a mountain flying instructor before taking on this trip.
 
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