IFR departures in the Rockies.

gismo

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I thought I'd start a thread about people's experience and opinions WRT departures in IMC from airports like kjac such as the recent one that ended in disaster. I wanted a separate thread from the one directly related to that incident and ask that everyone leave out anything that would show up via Google for any family of the victims.

I noticed that the track followed the Teton 3 DP to the first turn which would have taken the flight to the west rather than the desired direction. After that the route led directly towards the RIV VOR.

The ORCAs in the area are about 16,000 and the terrain under the path from the turn to RIV includes peaks in the 13,500 MSL range within 4 nm of that course centerline. I can't see attempting this being "legal" let alone safe unless the plane was able to reach the 16,100 ORCA before leaving the DP unless there was a lower min vectoring altitude which isn't something a pilot would normally know.

So three questions to start:

1) How would you folks plan an IMC departure to the east. Let's assume benign IMC e.g. 1-2 mile vis in light snow with no ice in the forecast and a negative ice pirep with tops in the 15-16k range in the same area. Let's also assume that the winds aloft were in the 15-20 Kt range making for some orthographic turbulence but nothing nasty. The surface wind favors a takeoff to the south but the margins on a runway 1 departure are acceptable but still more risky than lifting off into the wind.

2) Assuming you didn't agree to accept terrain clearance responsibility, wouldn't ATC normally have given an altitude crossing restriction to a flight headed for terrain that was higher than 2000 ft below the plane's altitude.

3) Shouldn't ATC have gotten a low altitude alert (and passed that on to the pilot) when the flight was getting close to terrain less than 2000 ft below the plane's altitude?
 
1) How would you folks plan an IMC departure to the east. Let's assume benign IMC e.g. 1-2 mile vis in light snow with no ice in the forecast and a negative ice pirep with tops in the 15-16k range in the same area. Let's also assume that the winds aloft were in the 15-20 Kt range making for some orthographic turbulence but nothing nasty. The surface wind favors a takeoff to the south but the margins on a runway 1 departure are acceptable but still more risky than lifting off into the wind.

Since your scenario involves acceptable margins for a downwind takeoff, and assuming that I agreed with that assessment, if I met the takeoff minimums, I would take off to the north, fly the Geyser Four Departure to DNW, and join one of the eastbound airways from there.

If I didn't meet the takeoff minimums for that departure, but I did for the Teton Three Departure, then I would take off to the south, fly the latter departure to IDA, and then take either V365 and V298, or V330, to DNW.

Of course, once I get into controlled airspace, AND hear "radar contact," then I will follow whatever vectors ATC may give me, although I will be using the terrain database of my Garmin handheld to check their work.

I don't have answers to your other questions.
 
I'll repeat what I've been taught about IMC in the mountains: Don't, leave it to the folks who do it every day (with two qualified drivers in the front seats).

That's from the Colorado Pilots Association course. It's simple, easy to remember, and easy to apply. It might slow you down just a tad but it'll save a life.

I'm sure that's not what folks want to hear. Sorry. After driving around IFR for a little while now I fully agree with the CPA position.
 
There are only 2 single-engine aircraft suitable for mountain IFR - a Pilatus and an F16.

And to add another "words of wisdom" from the CPA course - Night flight in the mountains is the same as IMC. Don't. This comes from the instructors with decades of Rocky Mountain backcountry experience. Who am I to argue?
 
I'm going along with the thought that IFR in the mountains in the snow in small airplanes is not a good idea, especially when you need to climb to an altitude which is marginal even in good conditions.

As far as that departure procedure goes, I've gone direct from KICNE to the next waypoint a number of times but we were well about 14,000'. I've never gone out to IDA, however I can vaguely remember asking ATC in the past when I first saw that departure procedure if we had to do that and they said "no". I'm trying to remember if they usually give us direct to the next waypoint before we even reach KICNE but I don't recall.

I'm not sure why ATC allowed that airplane to enter an area with a higher MVA when it hadn't climbed up to that altitude yet. In my experience they will not let you do that unless you say you can maintain your own terrain separation but I don't know what the policy is for sure. We often fly from the Denver area to KPNA which is just to the west of the mountains where they are searching. The MVA is 16,000 until you get over the valley where it goes down to 14,000.

I'm pretty sure if that pilot had seen the mountains he was headed for he would have turned around or gone around them to the south. Sometimes being in the clouds can give you a false sense of security since you can't see what is around you.
 
I'll repeat what I've been taught about IMC in the mountains: Don't, leave it to the folks who do it every day (with two qualified drivers in the front seats).

To be fair, there are no shortage of people who say that regarding flying in IMC out east where we have nice, low MEAs. I had one person tell me flat out that single pilot IFR flight was unsafe, especially around Bravos. I take issue with that based on my experience.

As with anything else, it comes down to the specifics of the situation and making a good judgement call.

There are only 2 single-engine aircraft suitable for mountain IFR - a Pilatus and an F16.

You left out the TBM 850 and Piper Meridian.

Would I do it in the planes I fly? Not with my current knowledge base. I also fly piston twins with naturally aspirated engines. If I were flying a turbo Aztec and T310R it might be a little different, but I'm not, so it's a moot point. And once again, it would involve more knowledge than I presently have.

It surprised me significantly to see that someone was trying to make a trip like that in a Mooney. I have no idea of the specifics of that Mooney, but it likely wasn't a turbo variant with TKS. Even if it was, whether or not that would be a good idea is still questionable.
 
1) How would you folks plan an IMC departure to the east. Let's assume benign IMC e.g. 1-2 mile vis in light snow with no ice in the forecast and a negative ice pirep with tops in the 15-16k range in the same area. Let's also assume that the winds aloft were in the 15-20 Kt range making for some orthographic turbulence but nothing nasty. The surface wind favors a takeoff to the south but the margins on a runway 1 departure are acceptable but still more risky than lifting off into the wind.
Since the weather prohibits a climb in visual conditions to 10,800, you're pretty well stuck with either Runway 19 with the TETON 3 to IDA, or Runway 1 with the GEYSER 4 to NALSI. Obviously, if we're eastbound, we're looking to get to DNW, so the shortest route would be Runway 1/GEYSER 4/NALSI and then V298 DNW. If the wind was light enough that I could make a takeoff on Runway 1 and still make the 450 ft/nm gradient up to 14,000, I could do that, and probably would, but I'd be looking hard at my enroute climb gradient based on climb speed (remembering to convert indicated to true), climb rate, and winds aloft up to 14K. Otherwise, I don't see any good choice but to take off on Runway 19, do the TETON 3, and once in radar contact and above the MVA for the transition, get turned off the SID to join V298 eastbound.

2) Assuming you didn't agree to accept terrain clearance responsibility,
In that case, you don't get your IFR clearance until you're above the MIA. Since the controlled airspace goes down to the surface over KJAC, that means you wait for the weather to clear enough to climb VFR to where ATC can see you on radar.

3) Shouldn't ATC have gotten a low altitude alert (and passed that on to the pilot) when the flight was getting close to terrain less than 2000 ft below the plane's altitude?
I haven't read the info on what happened, but that would require the airplane to be in radar contact. Was it?

Add:

Just went back to the original thread and saw the filed route of flight "TETON3 KICNE RIW DDY ECS RAP PHP." Since KICNE isn't on any airway, the route segment KICNE-RIW is undefined, and the pilot would have to determine a minimum IFR altitude for that segment IAW 91.177, which an examination of the sectional suggests would be 15,800. The OROCA for that per the L-chart is 16,100, and it would also entail departing controlled airspace, through which the controller cannot provide a clearance or an assigned altitude. However, it was posted in that thread that the controller told the pilot to climb to 15,800, so the controller must have had both radar contact and terrain data enough to tell the pilot to climb, which suggests the controller did get a low-altitude alert and responded.
 
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One can probably come up with a lot more singles with performance that equals or exceeds the least of those mentioned so far, but that's not the point. The point is that 450 ft/nm climb gradient all the way to 14,000 feet on the GEYSER SID, and if you do the math (including converting indicated airspeed in the climb to true airspeed and factoring in winds), there aren't many (if any) single engine airplanes without something spinning about 15,000 RPM under the hood which can do the necessary job. But there aren't a lot of twins which can do it, either, without a turbine wheel spinning somewhere in each engine compartment.
 
To be fair, there are no shortage of people who say that regarding flying in IMC out east where we have nice, low MEAs. I had one person tell me flat out that single pilot IFR flight was unsafe, especially around Bravos. I take issue with that based on my experience.

Of course it's a point that the chickin-littles (deliberate mispeling) say not to fly IMC, night, or on windy days or what-have-you.

To be fair to the CPA folks, they say nothing of the sort. They strive to give very good advice for flying around the big piles of rock. I feel no shame what-so-ever in parroting the party line and giving credit where it is due.

It's unfortunate when folks find it difficult to learn from others' mistakes and the nice folks in CAP and the voluteer SAR teams have to go pick-up pieces and parts on the hillsides. I suppose it is also just human nature to say something along the lines of "I can do that" when many others say and write just the opposite. Some folks try to walk both sides of the fence - remember Sparky?

I know that GPS gives a lot of confidence for navigation and terrain avoidance. I know a couple locals who do go into the mountains when it's IMC. They're in deiced singles so maybe they've got enough edge to survive. My choice is to avoid IMC in the tall hills. It surely is a lot of fun to fly around'em in good weather...
 
There are only 2 single-engine aircraft suitable for mountain IFR - a Pilatus and an F16.

And to add another "words of wisdom" from the CPA course - Night flight in the mountains is the same as IMC. Don't. This comes from the instructors with decades of Rocky Mountain backcountry experience. Who am I to argue?

What's wrong with tubocharged single pistons designed to operate @ 24,000 ft??
 
Climb angle. Piston singles don't have enough excess power to get the climb angle needed for the mountain departures.

I'm having a hard time finding climb specs for high altitude (tried to find them for the Acclaim type S). Do you know where I could find some specs??

EDIT: Found some info on the Acclaim type S. It can climb at 1200 fpm to 17,000 ft, and at 900fpm up to 25,000.

http://www.mooneypilots.com/mapalog/2008_M20TN.pdf
 
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EDIT: Found some info on the Acclaim type S. It can climb at 1200 fpm to 17,000 ft, and at 900fpm up to 25,000.
That article shows 1200 ft/min at 120 KIAS. At 14,000 MSL, that translates to about 150 KTAS, which converts to a climb gradient of 480 ft/nm even at the top of the climb. That's plenty for the GEYSER 4 out of KJAC (min 450 ft/nm).
 
That article shows 1200 ft/min at 120 KIAS. At 14,000 MSL, that translates to about 150 KTAS, which converts to a climb gradient of 480 ft/nm even at the top of the climb. That's plenty for the GEYSER 4 out of KJAC (min 450 ft/nm).

So in other words, it takes a plane with performance close to the Acclaim to operate in mountian airports.
 
So in other words, it takes a plane with performance close to the Acclaim to operate in mountian airports.
Well, at least this mountain airport. It's all situations and numbers. Others might need more, and still others might require less. You have to look at the terrain, and the procedures, and the weather, and the airplane's performance under those conditions all together to make a decision for that airport and that airplane on that day.

But as a generalization (subject to all the fine-print legal disclaimers you can imagine), I'd say that either a turbocharger or a turbine engine is essential for regular IFR operations in the Rockies. However, I would not say that it can't be done safely without a turbine engine.
 
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Also keep in mind that your climb gradient can often be lower for higher performance aircraft.

Observation from a 172 pilot flying a Lancair: "Usually I'm at pattern altitude by this point, not at treetop level."
 
Climb angle. Piston singles don't have enough excess power to get the climb angle needed for the mountain departures.
That's a generalization and it's often not true for TC singles. Most TC piston singles I can think of can achieve a decent climb gradient at high altitudes.

-Felix
 
For aircraft with enough performance for the high MEAs but that don't meet the glimb gradient, circle-climbing over the airport might be an option.
 
The ORCAs in the area are about 16,000 and the terrain under the path from the turn to RIV includes peaks in the 13,500 MSL range within 4 nm of that course centerline. I can't see attempting this being "legal" let alone safe unless the plane was able to reach the 16,100 ORCA before leaving the DP unless there was a lower min vectoring altitude which isn't something a pilot would normally know.

By staying on published routes, the OROCA is not an issue. The highest MEA I see in the departure area is 15,000.
 
For aircraft with enough performance for the high MEAs but that don't meet the glimb gradient, circle-climbing over the airport might be an option.

That'll work if the DP includes a climb in hold over the airport.
 
So in other words, it takes a plane with performance close to the Acclaim to operate in mountian airports.

I don't know about the Acclaim but I can't maintain a max performance climb for very long before the CHT moves to unacceptable levels. The book sez to go to cruise climb as soon as possible and the CHT will tell me to do it in five minutes or so.

Gotta look at heat management...
 
For aircraft with enough performance for the high MEAs but that don't meet the glimb gradient, circle-climbing over the airport might be an option.
The FAA anticipated this and put the option in the Jackson Hole SIDs for climbing visually to 10,800 over the airport and then proceeding out the SID at the "standard" 200 ft/nm gradient. However, that does mean you need visual conditions up to 10,800 MSL, or something like a 5000 foot ceiling and decent visibility, and that's not the conditions Lance gave for this discussion.
 
By staying on published routes, the OROCA is not an issue. The highest MEA I see in the departure area is 15,000.
The basis of this discussion was the ill-fated flight out of Jackson Hole last month. That pilot filed a route which not only went off published routes, but outside controlled airspace. The OROCA for that route (KICNE direct RIW) is 16,100, and the 91.177-derived minimum IFR altitude based on the sectional chart is 15,800.
 
That'll work if the DP includes a climb in hold over the airport.

How is that relevant? I was under the impression that pilots who are willing to assume responsibility for their own obstacle clearance are not obligated to follow an ODP, and I don't see any SIDs published for JAC.
 
That'll work if the DP includes a climb in hold over the airport.
Some permit a climb in holding at a designated fix over the airport, and those can be flown in less than VMC. However, the SID's out of KJAC permit that "climb overhead the airport" option only in "visual conditions."
 
I don't know about the Acclaim but I can't maintain a max performance climb for very long before the CHT moves to unacceptable levels. The book sez to go to cruise climb as soon as possible and the CHT will tell me to do it in five minutes or so.

Gotta look at heat management...
Out of curiosity, what sort of climb can you maintain (considering CHTs and such) at 15,000' with 1-2 people in the plane? 500 fpm?
 
The FAA anticipated this and put the option in the Jackson Hole SIDs for climbing visually to 10,800 over the airport and then proceeding out the SID at the "standard" 200 ft/nm gradient. However, that does mean you need visual conditions up to 10,800 MSL, or something like a 5000 foot ceiling and decent visibility, and that's not the conditions Lance gave for this discussion.

I wasn't talking about a visual climb; I was talking about an IMC climb.

I recognize that there are operations, such as for-hire, for whom the take-off minimums are mandatory, so an IMC circle-climb would not solve a gradient problem for them.
 
The basis of this discussion was the ill-fated flight out of Jackson Hole last month. That pilot filed a route which not only went off published routes, but outside controlled airspace. The OROCA for that route (KICNE direct RIW) is 16,100, and the 91.177-derived minimum IFR altitude based on the sectional chart is 15,800.

I thought the basis of this discussion was set by the OP's first sentence, which was "I thought I'd start a thread about people's experience and opinions WRT departures in IMC from airports like kjac such as the recent one that ended in disaster."

To me that sounds more general than just a discussion of one particular crash. It didn't sound to me like he was asking how you could do what that pilot did without having it end in a crash. This impression was reinforced by the OP's first question, "How would you folks plan an IMC departure to the east."
 
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I thought the basis of this discussion was set by the OP's first sentence, which was "I thought I'd start a thread about people's experience and opinions WRT departures in IMC from airports like kjac such as the recent one that ended in disaster."

To me that sounds more general than just a discussion of one particular crash. It didn't sound to me like he was asking how you could do what that pilot did without having it end in a crash. This impression was reinforced by the OP's first question, "How would you folks plan an IMC departure to the east."
I think both sides of that are worth discussing (what other pilots would have done to avoid a similar incident and what concepts, rules, and procedures folks who do IMC in the mountains use.
 
Out of curiosity, what sort of climb can you maintain (considering CHTs and such) at 15,000' with 1-2 people in the plane? 500 fpm?

At 75% the turboDakota will do about 500 fpm (or a bit less) and not get too hot as long as I run full rich from the "git-go." It does help a lot to be light so two people is okay. Any more than that and I do a lot of circling for altitude. If the CHTs creep up at a lean mixture setting then I'm just stuck with high temperatures - going to full rich after establishing the climb doesn't help.

At my more typical 65% power setting my climb drops to about 200 fpm (if I'm lucky) and I spend a lot of time climbing. It does tend to stay cooler.

Over the summer I spent more time at 75% and full rich for climbs than I had previously done in the aircraft. It seemed to work fairly well for CHTs but the little voice in the back of my head kept chiding me about power greater than 65% and engine life in the TSIO-360.

The book sez the aircraft will do about 500 fpm at max gross at max continuous (full power) and 15,000'. Based on observed performance, I believe the aircraft will make book numbers. Would I do it for very long? No way. I did climb out of Leadville one warm morning with two on board and 60 gallons of fuel at about 1,000 fpm. Performance was just about book.
 
How is that relevant? I was under the impression that pilots who are willing to assume responsibility for their own obstacle clearance are not obligated to follow an ODP, and I don't see any SIDs published for JAC.

I guess if you felt you could avoid the terrain, you could choose to climb over the airport.
I, however, will follow the ODP if I'm flying in IMC in the mountains. If the ODP is beyond the capability of my AC or myself, then I won't go.
 
Keep in mind that Lance's example...
Let's assume benign IMC e.g. 1-2 mile vis in light snow with no ice in the forecast and a negative ice pirep with tops in the 15-16k range in the same area. Let's also assume that the winds aloft were in the 15-20 Kt range making for some orthographic turbulence but nothing nasty.
...is not really likely to happen in real life.

If it's snowing on the ground and tops are 15-16K over the mountains you are likely to get icing whether or not it's been reported. In fact you are probably the most likely to get icing over the ridges near the tops of the clouds.
 
At 75% the turboDakota will do about 500 fpm (or a bit less) and not get too hot as long as I run full rich from the "git-go." It does help a lot to be light so two people is okay. Any more than that and I do a lot of circling for altitude. If the CHTs creep up at a lean mixture setting then I'm just stuck with high temperatures - going to full rich after establishing the climb doesn't help.

At my more typical 65% power setting my climb drops to about 200 fpm (if I'm lucky) and I spend a lot of time climbing. It does tend to stay cooler.

Over the summer I spent more time at 75% and full rich for climbs than I had previously done in the aircraft. It seemed to work fairly well for CHTs but the little voice in the back of my head kept chiding me about power greater than 65% and engine life in the TSIO-360.

The book sez the aircraft will do about 500 fpm at max gross at max continuous (full power) and 15,000'. Based on observed performance, I believe the aircraft will make book numbers. Would I do it for very long? No way. I did climb out of Leadville one warm morning with two on board and 60 gallons of fuel at about 1,000 fpm. Performance was just about book.
Interesting. I've seen 500 fpm in a NA Bonanza at 15,000' with 2 people and reasonable CHTs, so it does depend a lot on the engine.

1,000 fpm at Leadville seems good. I wonder if you could tweak the cooling/baffling a bit so that she stays cooler....
 
Interesting. I've seen 500 fpm in a NA Bonanza at 15,000' with 2 people and reasonable CHTs, so it does depend a lot on the engine.

1,000 fpm at Leadville seems good. I wonder if you could tweak the cooling/baffling a bit so that she stays cooler....

I think the 360 needs a bigger oil cooler. It has oil spray cooling of the pistons so cooler oil would have to help a bit.

An intercooler is being installed right now (Frankenkota) so we'll see what that does. The engine will be taking in more cool air since the engine air intake will be external. The flow that previously went into the engine will now be flowing by the heads and through the oil cooler. Of course there will be a lot more air dumping into the low pressure side of the cowling so I don't know what the net result will be.

On another note, I've felt the turboDakota needed a cowl flap for quite awhile now. Looking at other aircraft, the air intakes are oversized and there is no control of the low pressure on the downwind side of the baffles. A nice cowl flap would have fixed the airflow problem quite nicely.
 
I think the 360 needs a bigger oil cooler. It has oil spray cooling of the pistons so cooler oil would have to help a bit.

An intercooler is being installed right now (Frankenkota) so we'll see what that does. The engine will be taking in more cool air since the engine air intake will be external. The flow that previously went into the engine will now be flowing by the heads and through the oil cooler. Of course there will be a lot more air dumping into the low pressure side of the cowling so I don't know what the net result will be.

On another note, I've felt the turboDakota needed a cowl flap for quite awhile now. Looking at other aircraft, the air intakes are oversized and there is no control of the low pressure on the downwind side of the baffles. A nice cowl flap would have fixed the airflow problem quite nicely.
Oh I forgot your Dakota doesn't have an intercooler. That will make a huge difference!
 
Oh I forgot your Dakota doesn't have an intercooler. That will make a huge difference!

I certainly hope so. We had an 8 degree temp drop through the cooler while doing the low side fuel trim. I didn't participate in the high side fuel trim today so didn't see those numbers.

Planning to fly it Wednesday afternoon if all goes well...
 
The basis of this discussion was the ill-fated flight out of Jackson Hole last month. That pilot filed a route which not only went off published routes, but outside controlled airspace. The OROCA for that route (KICNE direct RIW) is 16,100, and the 91.177-derived minimum IFR altitude based on the sectional chart is 15,800.
Some more specific questions:

What are the consequences of flying in IMC ouside controlled airspace for a considerable distance (e.g. from KICNE to RIW)? Are there limitations to what ATC can do there? IOW what would I be giving up if I chose to follow the same path but at a "legal altitude".

For a part 91 flight, is it "legal" (let's not worry about how safe) for me to invent my own DP such as departing runway 19 and making a 180 at some point along JAC R192, returning to JAC, then flying the Geyser 4 DP to V298 (or going direct once above the ORCA)? If that was the plan what should be filed?

The only published route for an easterly departure would be Teton 3, IDA, V330 and that's between 155 and 190 nm further than some potential homebrew DPs not to mention that the 450 ft/nm climb to 14,000 isn't going to work for most piston powered airplanes.
 
Are there limitations to what ATC can do there?
I think the limitation is pretty obvious - they don't control it and you are on your own. Any IFR flight plan will start in a place where ATC can finally see you on their radars hence anything what you do before that - it is your own business. Flying in IMC in uncontrolled airspace is legal for us but not recommended.
 
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