A few years ago, I got the bug to fly small airplanes again. I trained for a few weeks at a local flight school, then rented a Cessna 172 to fly with my family. Renting has its limitations, so our family decided to get our own aircraft.
We fly our new-to-us Piper to Florida often (the airplane could probably find Orlando on its own), and we agreed it was time for something more adventurous.
So, my wife and I, and our two youngest (16 and 17) loaded up the airplane in Louisville, Kentucky and headed west for 11 days. I’ll share what I hope are interesting AvGeek details about the planning and execution of the trip, while sparing you the family vacation photos.
I’m not Lindbergh…
This trip was ambitious for me, but quite common in the general aviation community. Small aircraft are designed for these kinds of flights.
Most of my light aircraft experience is in Tennessee and Kentucky, where a 3,000 foot plateau is called a “mountain.” I had a lot of stuff to review and learn before tackling this adventure.
Pilots who regularly operate at high elevation airports are (or should be) familiar with planning this type of flying.
Our family’s airplane is a 1976 Piper PA-32 Cherokee Six. The aircraft has a 300 horsepower, normally aspirated (non-turbocharged) Lycoming engine. The “Six” can seat 6 (pilot + 5 passengers) in a 2-2-2 seating configuration. For this trip, the middle row seats were removed to make the cabin a 1st class four-seater.
Navigation equipment includes a Garmin GNS-530W GPS navigator and two VOR receivers for secondary navigation. An autopilot and Aspen primary flight display reduce workload on long flights. ADS-B provides real-time traffic information and almost-live NEXRAD radar and weather data.
Like my airline job, I fly nearly paperless using an iPad Mini and the ForeFlight app for navigation charts. My wife graciously keeps Foreflight on her iPad Air as an emergency backup.
Cherokee Six Specs
Weeks of Planning
Our goal was to fly to Santa Fe, New Mexico, visit a few days, then continue west to Flagstaff, Arizona to see the Grand Canyon.
Santa Fe is located 6,349 feet above sea level. Flagstaff is at 7,015 feet. Although not a problem for airliners, flying at high altitude airports presents challenges for pilots of small piston aircraft. Before heading west, I had to figure out if our aircraft could safely operate at these airports while loaded with fuel, luggage, and my family. I spent a few months researching aircraft performance and high altitude airport flying techniques.
Piston engines, wings, and propellers lose efficiency as they climb to less dense air at higher altitudes. An engine with a turbocharger can overcome this power loss by forcing air into the cylinders so the engine performs as it would at sea level (or better). Our Cherokee Six doesn’t have turbocharging, so our engine operates at significantly reduced power at higher altitudes.
The Altitude the Airplane “Thinks” it’s Flying
At low altitudes (like at sea level) the weight of the atmosphere pushes air molecules close together. More air molecules in engine cylinders allow the engine to produce more power; more air molecules moving across the propellor blades and wings means more efficient thrust and lift.
As altitude increases, air molecules spread out, resulting in less power and lift. When departing from a high altitude airport like Flagstaff, the aircraft will require a longer takeoff roll and have a slower climb due to less power available from the engine and reduced efficiency of the prop and wings.
High air temperature, high humidity, and low barometric pressure cause air molecules to spread even farther apart, further reducing power and efficiency. Although the elevation of Flagstaff airport is 7000 feet above sea level, these factors can make the air as “thin” as that found at 10,000 feet. So, the airplane performs like it’s at 10,000 feet.
To get an idea of how density altitude affects engine power, our 300 horsepower Lycoming produces only 195 horsepower for an 8000′ density altitude takeoff at Flagstaff.
High Density Altitude Accidents
High density altitude can have such a negative effect on performance that an aircraft may be unable to climb after takeoff. The results can be catastrophic. This graphic video illustrates how high density altitude can impact takeoff performance (amazingly, no one was seriously injured). This accident was likely preventable with proper education and planning.
[Warning: video shows an aircraft accident recorded from inside the cabin]
Pilots can calculate density altitude using a chart, rule-of-thumb, or an app (I use a free iOS app: AutoDens). Once the density altitude of an airport is known, accurate takeoff distance and climb performance can be calculated from aircraft performance charts. It’s up to the pilot to determine how much climb performance is needed for a safe takeoff and climb.
Manufacturer climb performance charts, like the one shown, are usually based on the maximum certificated takeoff weight, so they show a worst-case scenario. The blue lines are my rate of climb calculation before departing Flagstaff. At max takeoff weight, we should have an initial climb rate of about 600 feet per minute.
Improving Climb Performance
There are strategies to improve climb performance:
- Outside air temperature: Plan the takeoff when temperature (and density altitude) is lowest – right after sunrise. Not only do the lower temps provide better climb performance, the air is usually smooth.
- Takeoff into the wind: Departing into the wind won’t improve climb rate, but it will improve climb gradient (the angle of climb) which is helpful when there are obstacles ahead like trees or hills. Every pilot knows to take off into the wind, but sometimes pilots get in a hurry or become complacent.
- Lighten the load: A lighter aircraft will have better climb performance. Our family of four packed less than 50 pounds of luggage. I also departed with the minimum amount of fuel I was comfortable with (airlines use this strategy to increase performance and/or increase payload capacity). Thanks to our weight savings, we departed Santa Fe and Flagstaff nearly 400 pounds under max which significantly improved climb performance, and increased our margin of safety.
Trust the factory charts?
Piper built our aircraft over 45 years ago. Once an aircraft is certified by the FAA, the factory charts, like the climb chart above, are set in stone.
Over the past four decades, our aircraft had several (legal) modifications done by previous owners. Upgraded wheel pants, flap and aileron seals, vortex generators, and a 3-bladed prop have been added. The engine, though recently overhauled, may not perform the same as the 1976 factory-new engine. Will this aircraft perform exactly as the factory charts say it should? Maybe. Are my flying skills as polished as the Piper pilots that gathered the original data? Doubtful. Published charts are a good place to start, but I wanted to know precisely what climb performance to expect before flying my family to high altitude airports.
My Own Climb Chart
To find the answer, I loaded the airplane with full fuel, three volunteer passengers, and ballast to nearly max takeoff weight. We flew a few miles south of Louisville to an area free from air traffic and started a maximum performance climb. I configured the airplane the same way as noted on the Piper Climb chart: 105 mph (91 knots), flaps 10°, full throttle. Every 1000 feet we logged the time, altitude, and outside air temperature. After climbing to 12,000′ we headed back to the airport.
I entered our manually collected data, as well as data exported from the aircraft’s engine monitor into a Google spreadsheet. Pressure altitudes were converted to density altitude. Bad data caused by turbulence, turns, and other anomalies was discarded. The resulting plot was a pleasant surprise. The average climb rates were very close to the Piper factory chart.
Santa Fe and Flagstaff are hot in June, which means the density altitude at these airports will be at their worst while we are there. I set a maximum density altitude limit of 9,000 feet for takeoff. Both the Piper and my own data indicate that I should be able to climb a little better than 500 feet/min at that altitude; adequate to safely climb clear of terrain.
Time To Fly
Our aircraft can cruise for about 4 ½ hours plus an hour of reserve fuel at 130 knots. We like to keep our flights under 3 ½ hours so we can stretch, get a snack, and use a restroom. All of our flying started early in the mornings before afternoon turbulence and storms.
Flying Day 1: Louisville – Amarillo
We departed Louisville at 7:00 a.m. Our fuel/rest stop was Northwest Arkansas National airport in Bentonville, Arkansas. The fixed-base operator (Regional Jet Center) filled up our fuel tanks and provided complimentary hot dogs and ice cream for brunch. After 50 minutes, we were taxiing to the runway.
- Time to Bentonville: 3:39
- Distance: 430 nm
- Cruise altitude: 10,000 ft
Our destination for the day was the Rick Husband – Amarillo International Airport. After departing Bentonville, we flew southwest toward Oklahoma City where we intercepted US interstate I-40 and historic Route 66. Our route west, all the way to Flagstaff, closely followed these two roads; they are easily identified from the air and soon became familiar traveling companions.
On the Ground in Amarillo
We spend about 20 minutes to secure the plane for an overnight stay: we put on a canopy cover, engine cowling plugs, cover the pitot/static tube, install control locks (to prevent wind from moving the control surfaces), and tie down the aircraft to protect it from wind gusts.
With the plane safely tucked in for the night, we picked up our rental car and arrived at the Fairfield Inn by 2 p.m.
- Time to Amarillo: 3:13
- Distance: 366nm
- Cruise altitude: 10,000 ft
No visit to Amarillo is complete without stopping by the Big Texan Steak Ranch – Home of the 72oz Steak Challenge! [Note: We did not participate in the Steak Challenge, our regular-sized meals were more than enough!]
What is an FBO?
A fixed-base operator, or FBO, is like a full-service gas station for airplanes. FBO’s provide services for all kinds of aircraft; everything from a small Cessna 152 to a charter Boeing Business Jet.
Small Airfield FBO
Small airports typically have one FBO operated by the local municipality. Services often include self-service fuel pumps, a flight school, and a small terminal with a lounge, restrooms, and vending machines. Some FBO’s provide a loaner car for pilots to drive to a nearby restaurant.
Overnight parking is available for a small fee (~$10/night) or free if fuel is purchased. Hangar space is sometimes available for under $50/night – a nice option if storms are expected.
The Lebanon-Springfield airport in central Kentucky is a nice example of a small municipal airport terminal and FBO. They have a friendly staff… and warm chocolate chip cookies!
Busy Airport FBO
Airports in large cities often have two or more FBOs. These facilities cater to business and charter aircraft crews and passengers. Larger FBOs are executive passenger terminals and offer more amenities: lounges, showers, crew sleep rooms, conference rooms, and more. Services include catering, hotel & car reservations, aircraft maintenance, air taxi/charter, and deicing. Large FBOs can provide red carpet treatment to celebrities, dignitaries, and high rollers.
The extra perks provided by larger FBOs come at a cost. Fuel prices are a few dollars/gallon higher and service fees are often charged to cover extra expenses.
The TAC Air FBO in Lexington, Kentucky has an amazing lobby that features a classic Beechcraft Staggerwing to welcome travelers.
Flying Day 2: Amarillo – Santa Fe
Rise and shine! The 5 a.m. wake-up call came fast after an evening at the Big Texan and hotel pool. Early flying is smooth flying, so we were airborne by 7 a.m. for the short flight to Santa Fe, New Mexico. Watching the scenery change at 10,000 feet is amazing. You miss a lot flying at 35,000 feet.
- Time to Santa Fe: 2:08
- Distance: 216 nm
- Cruise altitude: 10,000 ft
Here’s a 3 minute video of our approach and landing in Santa Fe. The approach and taxi are time compressed; the landing is normal speed.
Flying Day 3: Santa Fe – Flagstaff
After 3 days of exploring Santa Fe, Bandelier National Monument, and Meow Wolf (amazing) it was time to continue west to Flagstaff.
This was our first high density altitude departure of the vacation. Our 7 a.m. takeoff temperature was 62°F/17°C, making the Santa Fe airport density altitude 7800 feet. To keep the aircraft as light as possible, I carried the minimum fuel necessary for a safe flight.
Anticipated flight time to Flagstaff was 2 hours, 10 minutes. I conservatively estimate fuel burn at 16 gallons/hour. Our flight time plus an hour of reserve fuel required 50 gallons.
The Six holds 84 gallons in 4 tanks; 25 gallons in each main tank and 17 in each wingtip. I had the FBO fill up our tip tanks and add 18 gallons to the left main. The right main tank remained empty, giving us 52 gallons of AvGas.
100LL (100 octane – low lead) aircraft fuel weighs 6 pounds/gallon. By having less-than-full tanks, our takeoff weight was reduced by 200 pounds. That’s a lot of weight for a small aircraft and significantly improved our climb performance.
Planning Pays Off
Our takeoff from Santa Fe’s runway 02 went exactly as planned. We noticed the anticipated slower-than-normal acceleration; with liftoff 2,500 feet down the 8,300 foot runway. Our initial climb rate was 500-600 feet/minute. I began a turn to the southwest after reaching 400 feet. At 1000 feet, I lowered the nose slightly (reducing climb rate) to accelerate and improve engine cooling.
It was rewarding to see the aircraft perform exactly as expected. Research and planning is worth the effort.
The views on this flight were by far the best we had seen. We flew west to Gallup and again intercepted our old friends I-40 and Route 66 toward Winslow, Arizona…
???? Well, I’m a standing on a corner in Winslow, Arizona
And such a fine sight to see… It’s a girl, my Lord, in a flatbed Ford
Slowin’ down to take a look at me ????“Take it Easy” – Eagles
Over Winslow, we turned west for the final 43 mile stretch to Flagstaff. Wildfires were a serious problem this summer. We could see smoke in several areas including the Coconino National Forest.
The Flagstaff airport was busy with firefighting aircraft arriving and departing. Phoenix Approach Control gave us a few delay vectors before turning us onto final approach. We flew through (and smelled) smoke, which can be seen in the video.
- Time to Flagstaff: 2:31
- Distance: 275 nm
- Cruise altitude: 12,000 ft
Flying Day 4: Grand Canyon Loop
On our 2nd morning in Flagstaff, we enjoyed a scenic flight over the Grand Canyon. After departing Flagstaff, we flew west to stay clear of the high terrain (volcanic formations). At Williams, AZ, we headed north to the Canyon’s south rim and crossed northbound, then southbound before returning to Flagstaff.
The airspace over the Grand Canyon can be busy. To reduce collision risk and control noise pollution, the FAA designates the Canyon a Special Flight Rules Area (SFRA). Pilots must follow the rules and carefully plan their routes over this national treasure.
You can find out more about our flight over the National Park, including planning tips and video, in my upcoming article: Flying the Grand Canyon.
- Round trip time: 1:34
- Total Distance: 193 nm
- Cruise altitude: 11,500 ft (northbound) and 10,500 ft (southbound)
Flying Day 5: Flagstaff – Dumas
Time to head home. Our takeoff from Flagstaff to Albuquerque was similar to our Santa Fe departure: similar flight time and a density altitude of 8,800′, I used the same fuel load: 3 tanks filled with 52 gallons.
Avoiding Obstacles After Takeoff
Airports with high terrain or obstacles in the vicinity often have special procedures to help pilots avoid hitting stuff after takeoff (really important). Both Flagstaff and Santa Fe have these procedures. The guidance for Flagstaff is straightforward…
Obstacle Departure Procedure (ODP)
The text block on the left of the image is the Obstacle Departure Procedure (ODP). It’s technically an IFR procedure, but can be used by any pilot to assure clearance from obstacles.
When taking off to the northeast, make an immediate right turn and intercept a course to fly southbound. When taking off to the southwest, make a slight left turn after takeoff and intercept the course southbound.
After climbing to 9000′, it is safe to turn back north and continue the climb. Following this procedure and maintaining a standard climb gradient of 200 feet/nautical mile will keep the aircraft clear of obstacles.
Standard Instrument Departure (SID)
The procedure on the right is the Flagstaff One Instrument Departure Procedure (SID). It’s used by aircraft operating under Instrument Flight Rules (IFR – flying in the clouds). It’s very similar to the obstacle departure procedure and, like the ODP, guarantees clearance from obstacles.
Since I filed an IFR flight plan, I requested the Flagstaff One SID. After takeoff, the SID directs the pilot to fly south to the OATES intersection near Sedona, AZ. When reaching OATES at 10,500 feet or higher, the aircraft can safely turn any direction and continue climbing on course.
After takeoff, we followed the Flagstaff One SID toward Sedona. We spent the previous day hiking in Red Rock State Park, so it was fun seeing the area from above. When we reached the OATES intersection, I pointed the Six toward Winslow.
If you’re in the Flagstaff area, be sure to fly over or visit Meteor Crater (aka: Berringer Crater). We did both!
Meteor Crater was formed about 50,000 years ago when a 160 foot wide nickel-iron meteorite impacted the site at 29,000 mph. Most of the meteorite was vaporized on impact, leaving only small fragments in the vicinity. The resulting crater is nearly a mile wide and 560 feet deep.
We flew 5,500 feet above the crater (11,000′ msl). It’s impressive from both the visitor center and in flight. If you’re in the neighborhood, the Discovery Center and views are worth the $20 fee.
Our fuel stop was at Albuquerque’s Double Eagle II airport. We enjoyed a cook-to-order breakfast at the Bombing Range Cafe, located in the Bode Aero Services FBO.
- Time to Albuquerque: 2:19
- Distance: 240 nm
- Cruise altitude: 11,000 ft
From Albuquerque, we flew another two hours to Moore County airport in Dumas, Texas to spend the night. The folks at the Moore County FBO helped us find discounted hotel rooms and loaned their courtesy car. Wonderful hospitality and low fuel prices.
- Flight time to Dumas: 2:15
- Distance: 238 nm
- Cruise altitude: 11,000 ft
Flying Day 6: Dumas – Louisville
Our final day on the road. It rained during the night in northern Texas, so the Six had a nice bath to rinse off the red Santa Fe dust. We departed after breakfast and climbed above the remaining low clouds headed for Branson, Missouri.
- Flight time to Branson: 3:34
- Distance: 429 nm
- Cruise altitude: 9,000 ft
Branson’s Jet Center FBO is a rustic, modern facility that includes a small diner. We were ready to get home so we ordered lunch to-go while the staff topped off our fuel tanks. We enjoyed an excellent airborne picnic of paninis and burgers on our flight to Louisville.
The final leg of our trip took us over Cairo, Illinois at the confluence of the Ohio and Mississippi rivers. In the photo, the muddy river is the Mighty Miss.
- Flight time to Louisville: 3:02
- Distance: 374 nm
- Cruise altitude: 9,000 ft
- Total Flight Time: 24 hours, 15 minutes
- Distance Flown: 2,760 nm (3,176 sm or 5,111 km)
If you’re a pilot planning a trip to high elevation airports, here are a few of the resources I found helpful.
FAA Seminar: Density Altitude and Aircraft Performance (PDF) with Dr. Amy L. Hoover. This document is priceless. It’s filled with theory, rules-of-thumb, and accident analysis that will keep you safe. It is my number one resource.
Free iOS app to calculate Density Altitude: AutoDens.
FAA Publication: Density Altitude (PDF) Includes description and use of a Koch Chart.
Interactive Koch Chart at Takeofflanding.com – Generic chart to conservatively estimate takeoff/climb performance. Helpful for older aircraft with limited performance data. If you Google “Koch Chart” you’ll find plenty of example images. Save one on your iPad for reference.