Mounting Flying in Colorado

Frank's Mountain Flying Adventure

On July 2nd, 1998, I flew a dual cross-country trip in the Rocky Mountains, including a landing at Leadville, the highest airport in North America, in a 1963 Cessna 182 Skylane, with a CFI (certificated flight instructor) and a friend as a passenger. Here's a description of the trip.

Caution: any of the hypertext-linked images are pretty big files (pushing a Meg). The inline versions on this page are pretty small, shrunken and cropped images, designed to be somewhat friendly for slow connections. Most photos aloft were taken by Tungsten Alcazar.

The Preliminaries

Camilo/Tungsten (I will probably refer to him by either of those names) and I arrived at the Meadow Lakes Airport (00V) just before 8:30am. It was IFR conditions due to morning fog, but that was rapidly improving. Camilo and I looked around at some of the planes that were tied down, when a truck pulls in. The door opens and two wiener dogs get out and start barking. Rudy, the owner of the FBO, stepped out of the truck and introduces himself. I had spoken to him on the phone earlier to arrange for the flight. He lets us into the FBO, and shortly after that John, the CFI arrives.

The next items cover the basic three components of any flight: the pilot, the plan, and the plane.

The Pilot

At this point, I had a little over 300 hours, and a complex endorsement (from flying our Mooney) though no high-performance endorsement (for a plane with over 200 horsepower). The instructor was John Fagan, an experienced instructor (CFII, MEI, etc.) originally from that region, who had spent time in New Jersey and Ottawa (flying seaplanes while in Canada, but never transferring that rating when back in the states), and has flown that route before.

The Plan

The first thing they did was show me the Jeppeson videotape on mountain flying, which is a good introduction to some of the issues involved in flying in the mountains (like lack of VOR reception, updrafts/downdrafts, turbulence caused by the mountains, route planning, how to fly over ridges, etc.). Afterwards, Rudy said that they agree with most of the tape, and that if you follow it, you will be safe, however... (basically implying that there might be a few practical issues that they do differently; to be honest, there weren't many differences I noticed).

John then went over the flight plan. He had planned the route, and had already called the airports to check the conditions there, which were good. The winds aloft up to 12,000 were less than 10 knots, which is good, since that means that turbulence should not be a factor. He had a chart put out by the state ("not for navigation") that showed recommended routes through the passes, as well as a current sectional chart with the course marked. He also had excerpts from an airport directory (not the A/FD) that had pertinent information for all the airports that would be near our route, such as runways and layout, traffic pattern altitude, etc. Finally, he had a road map, to show "the big picture" of where we'd be going, and indeed, we would be following some of the roads.

It looked like a go.

After that, he reviewed my logbook and experience and asked me about what I've flown. Since I hadn't flown a Skylane before, he reviewed the important numbers (takeoff, cruise, approach speeds, etc.). And also, the big difference is that other than during engine start, we never run with a full rich mixture.

The Plane

The plane, N3544U, is a 1963 Cessna Skylane, with a fixed landing gear, and constant speed propeller with its 230 HP engine. A pilot cannot serve as PIC (pilot-in-command) of a plane with an engine with more than 200 HP, without an endorsement from a CFI. The plane had a two-place intercom, which was unfortunate for Camilo, since that meant he couldn't hear the radio and without ear-plugs, had to endure the racket (which apparently wasn't too bad). John has said that the 182 tends to be a bit nose-heavy during landing, and that when flying solo, he'd often just put a case of oil in the back, to help balance things. Since Camilo would be there, that shouldn't be a problem. Camilo was happy to learn his true purpose: ballast, and his value as a person: equal to a case of oil.

In some ways, it was similar to our Cessna 150, as its flaps had an up/down, but no detent for specific settings. The airspeeds were in MPH, and the instrument panel layout was different than the standardized layout for the 6 main instruments (airspeed, turn coordinator, attitude, heading, altimeter, VSI). The plane was not IFR certified, as it hadn't had the necessary inspections. The interior was quite nice and had been redone within the last few years. We did a pre-flight inspection, and then boarded.

Touch and Go for a While

Since I was unfamiliar with the plane, I had suggested doing a few touch and go landings to get the feel of it. John had said that he was going to recommend that as well. 44U started nicely and after an initial leaning of the mixture we taxied to runway 35.

We took the active, applied full power and took off. It's a heavy plane, heavier than a Skyhawk, comparable to a Mooney, although the response was slower, and more truck-like, than a Skyhawk (nothing like a Mooney). At 6000' MSL (mean sea level), the effects of the thinner are start to become noticeable. The first of which is that the ground-speed is a good deal higher than the indicated airspeed. This means that things happen faster, the approach speed is faster than the "normal" speed, and that a wider pattern must be flown in order to avoid overshooting the runway when turning onto final approach.

The two landings were pretty uneventful. On the takeoff, the plane starts to shudder around the rotation speed, as if it's letting the pilot know it's ready to fly. After that, we head out on our trip.

Mountain Flying

Westward Across the Mountains

We depart the traffic pattern to the north, from the downwind leg, heading north of Colorado Springs. We pass by Black Forest, on a heading of west. This takes us just north of the United States Air Force Academy, which has an Alert Area in the northwest area of their airspace, where there is a lot of sailplane, motorglider, and parachute activity. Our course will keep us north of them.

The mountains to the west of the Academy are about 9500'. We decided we had sufficient altitude to cross it as we were at 10,500, climbing to an altitude of 12,500', before approaching it (the other option would be to circle and climb before crossing).

[photo of first hill and valley beyond it]

Once past that ridge, we were in a flat valley area, pretty barren, except for occasional roads that went nowhere. Our course paralleled Route 24, through Wilkerson Pass.

[photo of Rt. 24 and not a whole lot else]

Just past Antero Reservoir, we had a choice. We could pass either north or south of a 13,300' mountain. The north path would save perhaps two minutes. It might be on the windward side of that hill, possibly having an updraft. Then again, it might not, and to the north of that mountain were mountains. The south path had the advantage of having relatively flat land to the south of it. Either path would then follow the Arkansas River north to Leadville. While the winds were pretty light, we decided to be conservative and take the south path.

We intercepted the river just north of Buena Vista (pronounced "byoona vista") and followed the river. The valley below was around 8500' and we could see the white water of the river below us.

Leadville

The weather was pretty clear (a few high clouds with good visibility). John mentioned that we had to be careful about planes that might be departing the area, as they would be following the same valley. A Beech Baron just ahead of us contacted the airport on the common frequency for an airport advisory. They wind favored landing to the north and the local altimeter setting was 30.43, a very high setting. As I dialed it in, and stopped and considered, the Baron pilot questioned the setting "You guys must have some real high pressure." and they confirmed that setting (in reality, they were probably a little high). We would land with a straight in approach, number two behind the baron, who wouldn't be a factor, as his twin engines would keep him going a good deal faster than us. John made the appropriate radio calls.

We also heard another plane (a Cessna) announce that he was back-taxiing on the runway for a departure, seemingly oblivious to the two planes that were now on final approach. The Cessna MIGHT have been able to depart before the Baron, but the Baron decided he didn't want to risk it, and executed a go-around. As we got close, I had to slow us down and reconfigure us for the approach, a straight-in, without the cues of the traffic pattern that I was used to, in my vast experience of two whole landings in that plane. In addition, my Mooney experience made me cautious of trying to lose altitude (Mooney's often have difficulty losing altitude, as pointing them down only builds excessive airspeed, which results in excessive landing distances). We were about 1000' AGL (above ground level) and a mile from the threshold. I said I didn't like it and was going to break off the approach and try again. John was agreeable. This is our view of the Leadville runway from either a really poorly aligned final approach, or an offset upwind/departure leg (and yes, we did intentionally offset that leg once we broke off the approach).

We announced our intention (flying a bit to the right of the runway on the upwind/departure leg) and that we'd follow behind the Baron. I did get a little confused as to altitudes (I wasn't used to seeing the altimeter that high...or low (10,000' hand was on 1, the 1,000' hand was between 0 and 1)), and climbed to about 1000' ABOVE traffic pattern altitude. I was thinking "boy, that Baron is flying the pattern low" as well as "boy, that's a small runway." John reminded me about the altitude as we turned crosswind ("ooops!") and I had things back under control and stabilized by the time we were at the end of the downwind leg. He also advised me not to be fooled by the upslope of the runway, which would lead me to think I was too high. The landing was pretty uneventful, although the ground-speed was pretty fast. We taxied to the FBO and shut down, to take some pictures at "The Highest Airport in North America."

After snacks, rest room break, photos, postcard, and just admiring the beautiful view of the snow-capped mountains that surrounded the airport, we were ready to go. The pre-flight walk-around showed everything as ready to go. We set the altimeter to the field's altitude, just under 10,000'. Again, an odd thing to see, as I'm used to Ithaca's 1100' above sea level altitude as being "ground level." Starting the engine proved to be more difficult, until we leaned the mixture while starting it. The engine wouldn't start at full-rich at this altitude. The temperature outside was around the mid-60s. Standard temperature (upon which the performance tables are based) at that altitude would be 23F, so the "density altitude" (altitude the engine thinks it's at, performance-wise) would be well into 12,000'.

Departure

We back-taxied to the end of the runway, did the engine run-up in the run-up area just to the side of runway 34, and then taxied onto the runway, admiring the fake pink lawn flamingos in the grassy area between the runway and the run-up area. Full throttle was delivering about 19" of manifold pressure, much lower than the approximately 28" I'm used to seeing when taking off at 1100'. The takeoff roll took a LONG time. The runway is 6000' long, and we must've used about 4000 on the roll before rotating. The plane was very slow at responding, and ponderously crept into the air. The area past the end of the runway is flat for several miles before the mountains, which would give us time to climb, so we weren't in immediate danger. I wanted to make sure we had both airspeed and climb rate, and tried to maintain Vy (best rate-of-climb speed). I also wanted to see at least 300'/minute of climb once things stabilized. On downwind, we were creeping up to the traffic pattern altitude and things looked acceptable. So we departed to the south, back down the river valley. This time, we'd take a more southern route back, eventually winding up south of Colorado Springs.

As we were about 15 miles south, we heard a LearJet 15 call in to do a practice instrument approach at Leadville. He was no factor, as he was already within 5 miles of the airport. His call-sign started with "Smokey" and John speculated that he might have been associated with a fire patrol or similar.

[photo of the valley south of Leadville]

While flying down the valley, we saw virga, rain aloft that doesn't make it to the ground. Virga is common in that area, since the air tends to be dry enough that the rain can be reabsorbed before it hits the ground. It was thin, and while flying through it we would remain in Visual Meteorological Conditions (VMC), which is a requirement when flying under VFR (Visual Flight Rules). I did try to skirt it a little to the left. As we passed near it, we hit a downdraft. We were 2 to 3 thousand feet above the ground, so we had altitude to spare. After losing about 500', I made sure we were at full throttle and set the plane at Vy (max rate of climb speed). I checked the vertical speed indicator, and it showed that at this maximum climb speed we were now descending at 400 feet per minute! Once we had lost 1000 feet, John suggested a course that would get us away from the downdraft and we got out of it pretty quickly, and actually hit an updraft which helped us quickly climb back to our cruising altitude of 11,500'.

Somewhere before Buena Vista, we saw a "rain shaft." Not a curtain of rain, just a single column. John mentioned that the rain shafts tend to be pretty strong downdrafts. I made it a point to avoid it.

We passed Buena Vista and then Salida, where we would turn to the south east. At that point, I noticed the RPMs had crept up to 2500, which was just below the redline. The plan was to keep it at 2450. John saw it at the same time and started to pull it back a little. I leaned back and shouted to Camilo to show him how the RPM control works in a complex plane, as we had been talking about it earlier. I told him that as John pulled the knob back, the RPMs would drop. The conversation lasted perhaps 5 - 10 seconds, and John continued to turn the knob, slowly pulling it out, while the entire time the RPM gauge, as well as the pitch of the spinning prop, both seemed to be completely ignorant of the control input, and indeed, the needle crept closer to the redline almost in mockery of the controls.

Runaway Prop Governor

Constant-Speed Propellers

First, a brief digression into a high-performance/complex airplane, or to be more specific a plane with a constant-speed propeller. Airplanes with low horse-power engines have a fixed-pitch propeller, while ones with higher horse-power engines typically have a variable-pitch propeller (or "adjustable propeller" or "constant speed propeller"). The pitch of the propeller can be changed to allow the propeller to run more efficiently for the different phases of flight. The analogy is gears in a car. When starting, you want a low gear that runs quickly and provides a lot of power. When riding down the highway, you want a high gear that turns slower, and does not provide as much power but provides more fuel efficiency.

Similarly, a low-pitch to the propeller takes less of a "bite" out of the air and allows the propeller to spin quickly. This is called a "high RPM setting" and provides the maximum amount of power at a given throttle setting. A higher pitch angle makes the propeller take a bigger bite out of the air, which slows or loads the propeller down and is a "low RPM setting" and provides a greater fuel efficiency and greater endurance time.

Rather than control the pitch of the propeller itself, the cockpit control sets the speed of the propeller. A governor is a device which regulates the speed by using centripetal force to keep the driveshaft spinning at the same speed and which changes the pitch of the propeller blades as appropriate, if the shaft speed changes. So, changing the throttle or manifold pressure will NOT change the propeller's speed. It will change the blade's pitch angle, as more power increases the torque on the drive shaft which allows/forces the blades to have a greater angle in order to maintain the same speed. In addition to the constant speed feature, the governor has limits so that the propeller will not exceed its maximum (redline) speed, even at the high RPM setting. High pressure engine oil is used to actually control the pitch of the blades, so any break in the lines to regulate the blade pitch will cause a leak of engine oil under high pressure, which will rapidly cause an engine failure due to lack of lubrication.

OK, that's the background. The important thing to remember is that the propeller control was doing nothing, and the RPMs were increasing to and beyond the redline. Back to the story.

Redlining

John was adjusting the RPM control, and it was having no effect. He even cycled the control through the full travel (from high to low to high to low). The prop governor was no longer working and we no longer could regulate the pitch of the prop blades. In addition, since they were moving towards lower and lower pitch angle, they required less force to move, so the drive shaft (and propeller blades) were moving faster and faster. As the angle continued to decrease, the propeller would continue to increase in speed until the propeller, drive shaft, or engine itself was sufficiently damaged.

This is bad. However, the situation was far from hopeless, or even desperate. Up until this point, I have focused on the propeller control. This is a separate control from the throttle, which regulates the amount of fuel the engine receives and therefore the power that the engine produces. Planes with fixed-pitch propellers only have a throttle, and they control the RPMs by the throttle. The simple solution is exactly the same: reduce the throttle until the power output by the engine was no longer sufficient to overspeed the propeller. And that is exactly what we did. By reducing the manifold pressure (a way to measure the throttle setting) from 19" to 14", we were able to keep the propeller at 2500 RPM.

This is good. However, there is a drawback. By reducing the engine power so that it can only spin the flat-angled blade no faster than 2500 RPM, we are reducing the power of the engine significantly, which has a serious impact on climb power and cruise speed. In addition, the oil temperature gauge was high, at the top of the green arc, just below the red. By slowing down, we are also reducing the amount of air flowing through the cowling that cools the engine. Also, since we were more concerned about altitude than airspeed, the nose would be raised, which further reduces the airflow.

John thought that it might be possible that there was an oil leak, which would cause a failure of the prop governor. However, the oil is under high pressure, and any leak in the system would cause it to spray out. The airflow would then cause it to hit the cowling and windscreen and be very obvious to us. This was not the case. We had just passed the Salida airport, a minute before. We needed to decide if a 180 turn and precautionary landing was needed.

In a plane, it is important to determine the causes and effects of any problems quickly, as well as their impact. It is also important to be able to ELIMINATE possibilities that are NOT the cause. The plane was flying, the engine was running, the RPMs were under control, and the oil temperature had stabilized, albeit at a higher than normal level. Things were stable, and we were not in an immediate danger. John thought that it would be safe to continue eastbound towards Freemont, about 30 miles south of Colorado Springs, where we could make a precautionary landing there (and not be THAT far away from home). I agreed and we continued.

At this point, I was concentrating on flying the plane. I was relying on John for some backup information, such as the altitudes for the nearby airports and their traffic pattern altitudes, in case we needed it. I didn't want to reduce the power below 14", as we were already slow, and had poor climb performance. If the RPMs started to increase, I would let us climb a little, which loads down the prop and slows us up. According to the rules, eastbound, we should be at an odd thousand- foot altitude plus 500 feet, i.e., 11,500, but if we had to climb to 12,500, that was fine with me, as extra altitude equals extra time and extra options. I didn't want to climb above that, as you start to get into the rules for needing oxygen above that level. In addition, at points I would try to level off and get a little more speed, so we could keep things cool. We also opened the cowl flaps to increase the air-flow to the engine.

Burned Timber Mountain lay ahead of us, at 10000'. Once we crossed that, we would pretty much be in flat-lands for the rest of the trip back. This also meant that in case we had to make an emergency off-airport landing, there would be many good sites. And with over 2000' to spare, we had a comfortable margin, even at that power setting. We crossed it without incident.

Off Course or Pilotage 101

The basic rules of flying say that your priorities, in order of importance, are:

Aviate.
Navigate.
Communicate.

I was flying the plane, following the first rule. There was no one to talk to, so the third rule didn't really matter. As a matter of fact, at that point in time, we might have been in Class G or "uncontrolled" airspace, even though we were a couple thousand feet off the ground. As far as navigation, the mountains blocked our reception of any radio navigation beacons, and we would have required oxygen, had we been able to climb high enough above the mountains to receive the signals. So we were navigating by pilotage, which is visually following landmarks, roads, rivers, valleys, and the like. I was holding a course, and making sure we didn't fly into any mountains (or downdrafts for that matter). But that was about the extent of the navigation I was doing at that point in time. I was also very aware of the land below us, constantly looking for sites to land, in case that became necessary. I was also aware of the best-glide speed of the plane, as wel as our current airspeed, to make sure we didn't slow up too much in an attempt to climb.

Both John and I were distracted with monitoring and evaluating the condition of the plane and engine. Sound like rationalization for a mistake? Well, perhaps. Periodically, I also checked to make sure Camilo was alive and not puking his guts out. He was perfecctly happy, oblivious to the situation, occasionally taking pictures of the scenic landscape. At this point, I started to think it might have been a good thing that he didn't have a headset hooked to the intercom.

We came to our next checkpoint, Cañon City. Except that it didn't look right. It was too small. And the lake just to the northwest of the city wasn't shown on the chart. It didn't add up. And if things don't work, you have to recheck your assumptions, and possibly make new ones. We were off course. With all the fucking around with our heads buried in the gauges in the cockpit, we hadn't paid attention to the big picture of where we were going.

We were still heading southeast, and we should be heading east. After checking the chart, John determined that we were about 15 miles south of Cañon City. A heading of northeast should take us to Cañon City, and the Freeport airport would be just to the east of that. Curly Peak, at 9600', would be to our left, with Rudolph Mountain at 10300', to our right. The pass was around 7000'. Florence and the Freemont airport quickly came within sight.

Prop Governor Resurrection

Afterwards, Rudy theorized that there must've been some dirt in the oil that clogged the line for the prop governor mechanism. Something that would cause it to fail, but also possibly work its way free. Because that's what happened. The prop governor started working again, which meant it would change the angle of the prop blades as needed to set the prop RPMs to back to their appropriate speed, as set by the prop control. And the first sign of that was the change in RPMs.

Perhaps I hadn't mentioned, but the prop control had been left out in the low RPM setting. So what we heard was the propeller slowing down, rapidly losing RPMs until it got to the desired speed.

This sounds remarkably like a propeller slowing down, rapidly losing RPMs, until it STOPS (if your mind races ahead half-way through it).

To put it mildly, it got my attention.

"We're losing RPMs!" I said.

However, they did stabilize at a low setting, and, probably as the first reaction, John pushed in the prop control knob. And the prop RPMs came back up to full speed but below redline, just as it should. Pretty quickly, we realized everything was working as it should. John said he had never seen a runaway prop ever "just get better" but after a little experimentation with the prop and throttle control, it was apparent that things were working. At this point, our airport was about 15 minutes away, and things were working, and the land below us was very flat. So we decided to finish the trip.

After passing Freemont, John called up Approach Control for Colorado Springs, so we could get radar coverage, and we would be passing through their airspace on the way back to Meadow Lake. We would be following Route 115 north to Colorado Springs. To the east is a restricted area, where the Air Force shoots off ground and air based weapons. An area that's best avoided. Springs Approach advised us to remain west of Rt. 115. A couple miles west of 115 is Black Mountain, at 10100', so there was a limit as to how west we could go. We requested a descent to an altitude of 9,500, which was approved, and Springs Approach advised us to expect to cross over midfield of the Colorado Springs Airport on the way to our destination.

They then gave us a vector to take us right over the airport, and told us to remain at or above 9,500'. We passed overhead, saw airliners on the taxiways, 2,500' below us. The airport has both civil and military traffic and we saw various C-130 transport planes parked on one end of the airport. We were told to hold our heading due to traffic. This also brought us close to Meadow Lake.

Once it was in sight and the traffic they were controlling had passed, they cleared us for a VFR descent at our discretion, terminated the radar service, and told us to change to the local advisory frequency. After descending to traffic pattern height, 7700', and crossing the field, I turned onto the downwind leg, and set up for landing. There was a little crosswind, and I did a nice crosswind landing, with of the main wheels touching, then the other, then the nose. We taxied in, ending the trip. One of Camilo's ears got blocked in the final descent, probably due to some stuffiness from a cold from the previous week (which I didn't know about at the time) but otherwise, he was fine.

Wrap Up

We filled out all the paperwork, I got my logbook endorsement for high-performance airplanes, I paid the bill and we were done. It was a fun trip, and I even learned a few things there. I don't think I'd fly in the mountains on my own at this point, but I have a better understanding, and respect for, what's involved.

Back to Frank's Flying Pages.

Written on July 10th, 1998 by FNA.