From the Flight Deck Video Series: Complex Airfield Geometry

The FAA identified 7 airfield geometry configurations that most frequently lead to pilot challenges resulting in runway incursions and developed videos on these challenges. This series of 7 short videos on Complex Airfield Geometry is part of the FAA‘s From the Flight Deck video series.

From the Flight Deck uses aircraft mounted cameras to capture runway and taxiway footage and combines them with diagrams and visual graphics to clearly identify hot spots and other safety-sensitive items.

Density altitude dangers

I recently flew a trip from the Midwest to Reno, NV (KRNO). Reno is located in the northwest portion of the state just to the north of Lake Tahoe near the California border and on the eastern side of the Sierra Nevada Mountain range. Needless to say, it’s a gorgeous part of the world with endless recreational activities whether winter or summer or anytime in between. But the combination of high elevation and scorching hot temperatures during the summer, requires pilots to be mindful of high density altitude considerations.

High density altitude is the ultimate thief lurking in the shadows as it robs the aircraft of engine and propeller performance resulting in increased takeoff rolls and degraded climb performance. In other words, density altitude is the altitude at which the aircraft is performing. Technically speaking, density altitude is the vertical distance above sea level in the standard atmosphere at which a given density is to be found or pressure altitude corrected for nonstandard temperature. 

Density altitude is determined by first finding pressure altitude, and then correcting this altitude for nonstandard temperature variations. Air density is affected by changes in altitude, temperature, and humidity. High density altitude refers to thin air, while low density altitude refers to dense air. The conditions that result in a high density altitude are high elevations, low atmospheric pressures, high temperatures, high humidity, or some combination of these factors. Lower elevations, high atmospheric pressure, low temperatures, and low humidity are indicative of low density altitude. 

Humidity, also called relative humidity, refers to the amount of water vapor contained in the atmosphere and is expressed as a percentage of the maximum amount of water vapor the air can hold. This amount varies with temperature. Warm air holds more water vapor, while cold air holds less. Humidity alone is usually not considered an important factor in calculating density altitude and aircraft performance, but it is a contributing factor. 

As an example, consider the Reno Tahoe Airport with a field elevation of 4,044 feet MSL where the temperature is a comfortable 15 °C. Under these conditions, the density altitude is 5,416 feet. If the temperature rises to 30 °C, the density altitude increases to 7,077 feet. This means an aircraft would perform on takeoff as though the field elevation were 7,077 feet. In my particular case, this translates to a 22% increase in takeoff roll. The same scenario in a Cessna 172 Skyhawk results in a 12% increase in takeoff roll.

While many airports in areas that routinely deal with high density altitude conditions have adequate runway length for a wide variety of aircraft and conditions, you’re certainly not finished with the effects of density altitude after your ground roll. Because of the terrain surrounding the Reno Tahoe Airport, many of the published departure procedures require climb gradients of nearly 8%. In our jet aircraft, at a reduced weight, meeting those requirements were not an issue even at a temperature of 30 °C, but the calculation certainly had to be considered. And if the performance was not adequate, we would need to consider reducing weight (fuel), leaving earlier in the day with cooler temperatures or even moving the departure date.

If we go back to our Skyhawk example, at maximum weight and a temperature of 30 °C, we’re not able to achieve that type of climb gradient. Does that mean we’re grounded? Not necessarily. There are other options for departing the area including climbing above the airport until clear of obstacles, but we’d have to ensure we could do so in visual conditions. The more important point is that when we have the high elevation, high temperature (e.g. high density altitude) conditions, we must consider all aspects of aircraft performance when preparing for our flight and always have a plan. And in mountainous terrain, there’s even more to consider.

Webinar video: how to pass your FAA written in less time

It’s something all pilots have to do during training for a Private Pilot license — pass the FAA Knowledge Test. While this test has gotten a bad rap over the years from some, the reality is it’s a non-event when you approach it with the proper mindset and use the right study tools. In this webinar video, we’ll show how to use tried and true study methods using Sporty’s Learn to Fly Course to make the process an engaging and meaningful learning experience, and not just another exercise in rote memorization.

 

Kim

Video: the mental side of flight training

You know the requirements for flight training, and you might even have a school picked out. But what is it really like to start flight training? Beyond the mechanics of flying an airplane, what goes through the mind of a new student pilot? In this new video series from the popular Baron Pilot channel on YouTube, you’ll get a behind-the-scenes (and unfiltered) view of Kim’s flight training journey. It’s fun and rewarding, but learning to fly isn’t always easy.

Video courtesy of Baron Pilot.

Webinar video: ForeFlight – what’s new and advanced tips

Hear from ForeFlight’s Josh Berman on what’s new in aviation’s top app, plus some lesser-known advanced tips. If you know the basics of ForeFlight, this information-packed hour will take your skills to the next level.

License to learn and a long cross-country

July 27, 1980. I was lying on the wet ramp at the Morgantown, WV (KMGW), airport in front of the Flight Service Station (FSS). I was flat on my back, my clothes soaking up the ponded water. Peering up through the then-sprinkling rain, I noticed a small crowd of interested observers asking if I was all right.

My thoughts went back 24 days earlier to July 3, the day I passed my private check ride. Darrell, my designated pilot examiner, was typing up my temporary Private Pilot Certificate. As he handed it to me he said, “It’s not only a license to fly; it is a license to learn.”

I thought I knew what he meant as I began my first really long cross-country flight from Rochester, MN, to Flemingsburg, KY. I was working in Rochester for Babcock Swine, Inc. At Babcock, we sold breeding hogs to farmers throughout the United States and Canada. I was in the technical services department. My job included helping our customers select replacement females and moving them into the breeding herd. I won’t go into all the details, but if you’ve ever seen animal husbandry episodes with Mike Rowe on Dirty Jobs, you may develop a good idea of some of the process.

I couldn’t afford to buy an airplane so I had joined the Southeast Minnesota Flying Club. A well-run flying club is a great way to economically and conveniently access a variety of aircraft. At the time this club had a Cessna 150 (in which I took my check ride), a 182, and a 172.

I needed to visit some customers in southern Pennsylvania. I had checked out the eighteen year-old 172, N159AE, for my extended weeklong trip on Friday, July 25.  My plan was to fly from Rochester (KRST) to Fleming – Mason Airport (KFGX) to spend the weekend with my parents. Then I would move on to my clients in Pennsylvania. After visiting the Rochester FSS (yes, there were a lot of Flight Service Stations back in those days) for my weather briefing, I was ready to launch.

The weather was clear to my fuel stop in Danville, Illinois (KDNV). That is when I found out we only know the weather at reporting locations—which at that time were towered airports, National Weather Service stations, and the FSSs. Al Gore had not yet invented the internet nor were there remote AWOS/ASOS stations. A layer of clouds near the Polo (PLL) VOR (nope, no GPS back then either) forced me to finish most of that leg less than 3,000 above the ground.

Lesson 1: I determined from this experience weather is as forecast only part of the time. Sometimes it may be better, but other times it will be worse so assume forecasts are more like opinions than facts. “This is what license to learn means,” I thought to myself as I was bumping along in the warm summer air. No, the big lesson was yet to come.

My mother was a worrier. I knew if she knew I was learning to fly she would worry about every lesson. So I hadn’t told her or Dad. At Danville, I phoned the house. “Can y’all come pick me up at the airport?” I asked.

“Are you coming into Cincinnati or Lexington?” she asked.

“No, the airport just 5 miles from your house on the Maysville Road,” was my reply.

“How are you getting there?”

“I’m flying myself in a Cessna 172,” I answered.  I could tell by the silence on the phone that the reality was sinking in.

“John [my dad] and I will come and pick you up,” she finally replied.

I had a delightful weekend on the farm with my family and planned on heading to Capital City Airport (KCXY) in Harrisburg, PA, Sunday afternoon. I looked up the Flight Service Station number in the phone book (for all you too young to have ever replaced a phonograph needle, before smart phones and the internet, we relied on these paper publications called phone books to look up numbers) and gave them a call. “Generally marginal VFR conditions exist across your route of flight with five to seven miles visibility and ceilings from 3,000 to 5,000 feet,” stated the briefer. “VFR flight is not recommended.”

VFR not recommended? What did he mean? After all, I was a Private Pilot with 75 hours. I knew the rules. All I needed was a 1,000 foot ceiling and three miles visibility to fly VFR. This forecast was for ceilings at least three times higher and twice the visibility. I determined I could easily make my flight to Harrisburg.

Lesson 2: Good judgment comes from experience; unfortunately, experience is usually gained from bad judgment.

Departing Fleming – Mason, I tuned in the York (YRK) VOR and I was on my way. The Ohio Valley in late July is usually hot and muggy. This day was no exception. There were some high clouds but mostly it was just hazy. “This must be what five miles of visibility looks like,” I thought to myself. I now know it was more like 10.

Rochester is located on the plains. Canadian air masses usually dominate. Normally the air is clear and you can see any rain coming for many miles. For the most part, the terrain is as flat as a day old beer and cell towers had not been invented yet. The truth was, although I knew I could legally fly VFR with 1,000 foot ceilings and three miles visibility, I hadn’t flown in any weather even approaching those legal numbers.

Now in the haze over West Virginia, I was feeling my way up the Ohio River Valley in visibility so low I could not distinguish the horizon. Whereas Minnesota was flat, the mountains of West Virginia were, well, mountainous. I had the uneasy combination of the ceilings above me getting lower and the ground below me getting higher.

Lesson 3: In the battle between mountains and airplanes, no matter how mighty the airplane and how meager the mountain, the mountain always wins.

Of course I had no autopilot and without the natural horizon, I was having some difficulty holding heading and altitude. After crossing the Parkersburg VOR (JPU) I set my course for Morgantown, where I would gladly take a break for gas and a restroom.

On the ground in Morgantown, I stepped into the FSS. In 1980, all those charts you study for the FAA knowledge test were affixed to bulletin boards on the wall—no computer terminals with weather in motion to study. Area forecasts came in on teletype machines while the latest composite radar was faxed in once per hour or so. The latest of these reports, probably an hour old, depicted rain (likely thundershowers) west of my route. I decided I needed to get on my way or I would have to stay in Morgantown, and I had an appointment outside of Harrisburg the following morning. The pigs were calling.

Lesson 4: The only place you have to be is where you are.

I departed Morgantown for the Indian Head VOR (IHD),  only 34 miles northeast. I wanted to climb to 5,500 feet but the clouds stopped my climb around 5,000.  A quick look at the sectional told me the highest terrain in this sector was 3,600 feet so I felt good about that, though a bit uneasy about the topography below me. The haze was thickening, the visibility was going down, and then the haze turned into rain—a hard rain. I could see the wing tips. I could see the ground straight down. The RPM began to drop and the engine started running rough. Now I’m sure there are some mighty nice people living in that part of the country but for some reason, the theme from the movie Deliverance started going through my mind.

Lesson 5: It is better to be on the ground wishing you were in the air, than in the air wishing you were on the ground.

All of a sudden, the training kicked in: full throttle, full carburetor heat, initiate a 180-degree turn back towards Morgantown only about 15 minutes away. Fortunately for me, the rain was mostly staying to my west off the right wing. I flew over a small airport near Farmington, WV. It looked inviting, but vacant. Being mission-oriented, I was still thinking about getting to the pig farm the next morning so I pressed on. Once at the MGW VOR, I turned northwest.

“Morgantown Tower, Skyhawk 159AE over the VOR, inbound for landing”

“Niner Alpha Echo, we have a thunderstorm in progress,” was the reply from the tower.

Just then, I saw the end of a runway protruding out of a wall of rain. “Tower, I see a runway! Request permission to land,” I broadcast as I turned the plane for the numbers.

“Niner Alpha Echo, cleared to land—runway and direction your choice.”

Within a couple of minutes I landed and rolled into another hard rain shower. I stopped the plane on the runway and radioed the tower for taxi instructions.

“Niner Alpha Echo, we can’t see you, state your position.”

“Not sure,” I replied “I can’t see much here either.”

“Niner Alpha Echo, hold your position, turn on your lights, we’ll send someone to find you.”

The rain ended as abruptly as it began. A maintenance truck approached with a flashing amber light on top and I followed it to the ramp. I shut down the airplane and opened the door. My left foot slipped off the landing gear and I rolled out of the airplane onto the ramp where this story began.

Lesson 6: No matter how bleak things appear, keep flying the airplane until all the parts quit moving. If it looks bad, don’t give up, fly as far into the wreck as possible. Things may just turn out better than you feared.

That night I caught a US Airways Beech 1900 from Morgantown to Pittsburgh, then on to Harrisburg. I rented a car and drove to the farms I intended to visit. I flew back on a 1900 to Morgantown, where the visibility was fine but the ceiling was less than 1,000 feet. In 1980, they actually went outside once an hour with a helium balloon, released it, and then timed how long it took the clouds to swallow it. Once the observation was made, it would be another hour until the next one.

Finally, the next day, the clouds parted and I headed back to Rochester. Once past the hills of southeastern Ohio, I was again over the familiar flat terrain of the midwestern farming country. I stopped to check weather at the FSS in Zanesville, OH, and Rockford, IL: severe clear, ceiling and visibility unlimited was the report at both stations. Of course, it started raining on me as I was taxiing to the hangar at Rochester (refer back to lesson 1).

During your training, tell your instructor you want to experience marginal weather. Give them a call next time visibility is near three miles. You may be surprised just how little visibility that really is and there are a lot more antennas today than back in 1980. If the aircraft does not have a panel-mounted GPS, buy yourself a portable ADS-B receiver to go along with your iPad. In addition to your position, they also provide weather and multitudes of other information.

Since that first long cross country, it has been my goal to make the subsequent ones as boring as possible. Take advantage of the lessons I have learned and feel free to leave a comment to share your own with the rest of us. And remember the words of my DPE thirty years ago: “It’s not only a license to fly; it is a license to learn.”

Keep flying… and learning.