DEN - CRQ in a GA single piston

[Keith Smith]

If you were tasked with flying that route, VFR in an unpressurized piston single, no Oxygen, which route would you take to cross the mountains and where would you stop for fuel? Assume a 650nm range.

Here's what I have so far:
http://skyvector.com/?ll=37.92036783985 ... :A.K2.KCRQ

I haven't focused on the tail end of the route, I'm not concerned about it. My concern is purely with the mountain crossing south and west of Denver.

[rgrazian]

Hi Keith,

I lived in Denver for several years. Those are some big mountains.

In an single-engine piston with no O2, I would cross pretty far south if going to CRQ. Flying the airways keep you at least 2000 feet above terrain and with-in range of back-up “VOR” navigation in the confusing mountains. This route is not very direct, but keeps you at or below 12,500 with suitable terrain clearance. Assuming your range was 650, you could stop for gas in PHX. I might stop in Albuquerque because there just isn’t a lot between there and PHX and wouldn’t want to take a chance with un-forecasted headwinds going westbound with no fuel options. Here’s a quick stab at it…
KDEN PUB CIM FTI V190 PXR V16 BLH V460 JLI KCRQ or
KDEN PUB CIM FTI V60 ABQ V190 PXR V16 BLH V460 JLI KCRQ

[Keith Smith]

Hi Rob,

Thanks for the suggestion. I reviewed the route closely. I'm not a big fan of airways in the areas with terrain because while they do provide 2k obstacle clearance, they can also exposing you to relatively high terrain for long periods of time. In other words, they give you 2k obstacle clearance and absolutely nothing else regarding terrain when compared to a custom VFR route that's hand tailored to minimize terrain exposure, even if the custom route results in less than 2k clearance for very brief stints.

I'm also not wild about the increase in distance. That's a pretty serious diversion for what, in my mind at least, is marginal gain. For now, I prefer the 20nm (7 mins) through the mountain pass early in the morning in calm conditions, and the 130nm shortcut it affords.

[rgrazian]

I didn't look closely, but maybe there's a road to follow through the pass. (aka - landing strip) Are you planning to do this for real...???

[Keith Smith]

Yes...there's a road, verified on sectional and xplane. Yes, planning on flying for real, possibly in 2 weeks.

[rgrazian]

Good Luck and fly safe. I once got caught in a freak snow storm crossing Monach Pass on my motorcycle... IN JUNE...!

[gavink42]

Here's my two cents worth. It does go a little out of the way, but see my disclaimers below.

The 3rd segment (between the two airports) contains the highest point of the flight, but it's not very long.

As for refueling, I would likely stop at Gallup (KGUP). This is the airport that I stopped planning at, and simply ran the course direct KCRQ from there.

Disclaimers:
- I have zero mountain flying experience, so would plan and fly such a trip very conservatively.
- I normally fly a P28A /A, so tend to look for VOR radials and nice distinct visual checkpoints.

http://skyvector.com/?ll=37.28465216309 ... :A.K2.KCRQ

Gavin

[Mark Hargrove]

If I had to make the trip you're considering at this time of year I would put the airplane on a trailer and drive -- and still not be sure of making it over the mountains.

I live in Longmont, just about 45 minutes or so north of DEN. The weather in Colorado is unbelievably volatile during March and April. We don't have the CB buildups that will happen come summer time, but weather can go from clear and cold to IMC with heavy icing in 30 minutes. This very morning I had an appointment in downtown Boulder at 9:30AM. It was clear, sunny, and quite nice -- low-50's. I left my jacket in my car and walked from a parking lot to a building about 1/4 mile away. When I returned to my car at 11:00AM it was snowing -- heavily -- the temperature had dropped 20 degrees and visibility was about 300 yards. It wasn't the most pleasant walk I've ever had.

While the 10-day extended forecast for Colorado looks good right now, I would put exactly zero trust in it -- I've lived here too long to believe anything the weather service thinks is going to happen over the Rockies.

[NM Doug]

I can vouch for the La Veta pass south of Pueblo - maybe marginally longer than what you have, but several pilots around here (Albuquerque) use it regularly on the way to the Denver area, and I've had good luck with it, too. The La Veta Pass AWOS was inop when I went, but it was a nonissue. Expect a few bumps with winds out of the SW, regardless of which pass you take.

My two cents!
Doug

[Peter Grey]

Hello KS,

I have flown routes similar to this (usually from PUB or COS going to PRC) on multiple occasions in aircraft varying from a C-150 to a DA-42 in the April/May timeframe. I'm going to assume that you are flying this in your L360.

First off Mark brings up some valid points. There are days where your route will not be doable due to IMC or severe turbulence (I'm going to ignore the DA issue as it's the L360, but for anyone else reading this, it's a very serious concern in smaller aircraft). If that happens the only route option would be down to LVS and then over (with consideration to my next point). Even this would have risk in mountain wave style turbulence.

Second is divert options, you can easily end up 50-100 miles from a suitable divert airport, your route actually does very well in this area. gavink42's route gets a bit far from airports for my liking between TAS and GUP and so does rgrazian's between FTI and around SJN.

So with that said here is what I think about your route and how I would change it:

I personally would avoid the MOAs that you penetrate during the route. This is a personal preference however.

Your route through the hayden pass is ok, I've never personally flown through that one, but it's well with the capability of your aircraft. My only concern with it is that you will need 12000' MSL to get a bare bones minimum 1000' ft clearance. And to be honest, I like more then that in case of downdrafts (which I have delt with in this area). I'd like 2000 ft clearance min, which brings you to 13000' ft. That's the hypoxia danger zone (even if legal).

I have the same issue with the wolf creek pass.

So with that in mind here is my route.

http://skyvector.com/?ll=33.77960391893 ... :A.K2.KCRQ

I ignore the last portion past the PHX area, but I would dog leg around the MOAs in west AZ.

I bring you down through the la veta pass as you can do it without breaking 10000', I wouldn't do it that low, but you could. That's the only mountain exposure in the entire route. The remainder of the dog legs are generally to keep you around other airports.

My route is longer by over 100NM, but lowers the required altitude down to 10000-11000 feet for a short portion of time (under 20 minutes) as opposed to 12-13k for a longer period (you'd be skirting the 12,500 feet for 30 minute rule, and while yes you can argue the "1 minute below then back up" part of that rule, that's a great way to pass out).

In terms of fuel stops, be careful of uncontrolled airports in this area unless all you want is fuel. I imagine after 650NM you will want food. Most of the airports that you fly over don't have a way to get off the airport for food (and no food on airport). Make sure you do your research on this.

Along my route "safe fuel stops" are SAF, AEG/ABQ, PAN (get some pie), and the PHX area (don't go to PHX).

Let me know if you have any questions.