Matching The Plane To The Mission

You can fly some practical transportation missions in simple airplanes, as long as you account for and mitigate some associated risks.

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Many of us fly, or have flown, some rather capable high-performance single-engine airplanes providing excellent long-distance transportation value and utility. Flying a Cirrus, Centurion, Bonanza or Mooney and cruising between 150-180 knots allows you to operate over the entire country on a practical basis. You can, however, achieve almost as much utility from simple fixed-gear airplanes, providing you know and account for their limitations, your “utility envelope” and certain associated risks.

Utility in this instance means transportation. By that I mean real transportation that can get you from A to B for personal and business purposes. If you’re just flying for recreation or making 40-mile trips for $100 hamburgers, just about anything with wings will do. On the other hand, if your main purpose is to travel hundreds of miles or more on something resembling a schedule, then most recreational airplanes don’t meet the requirements.

Minimum acceptable utility
I should first define what I consider to be the minimum type of airplane that provides the required level of utility that we are seeking. Let’s define “utility” in the context of this article and then we can focus on the airplane.
I know there are exceptions to this general rule. While I was serving as a missile launch officer in the USAF in the early `70s, I acquired a 1947 Cessna 120 and flew it all over the West, from Montana to New Mexico. But as economical as it was, the 120 would barely carry me and minimal luggage. There also were performance limitations—such as a 90-knot cruise speed—although the 120 was so light that even with only 85 horsepower I found it would get me through most of the intermountain region with only a few restrictions.

That was then, this is now, and I demand a little more comfort and ease of use than I did at age 23. General aviation’s demographic is changing and we older folks are of broader girth. Squeezing into a 120 and flying it four hours non-stop from Montana to Colorado at low altitude through summer turbulence is something I now define as torture, rather than adventure or utility.

So as a practical matter, I propose that simple fixed-gear airplanes—we’ll call them SFGA—such as the Cessna 172 or the Piper Warrior are the minimum that can provide acceptable transportation utility. We can add Diamond’s DA40, Tampicos and Tobagos, the Cirrus SR20 and even Cessna’s 182 Skylane models, plus the 235-hp Pipers, since their extra flexibility is only incremental.

All of these SFGA are roomier than light sport aircraft and legacy classic aircraft, can carry two people and their baggage without major limitations, and are capable of limited IFR operations. They can be fitted with modern avionics, including an autopilot. And they usually offer reliable transportation, within their limits.

But before I go charging off and claiming that a 172 or Warrior is the answer to anyone’s on-demand air transportation needs, let’s also define a realistic operational envelope for these airplanes. Again, I can offer a relevant example from my own experience.

In addition to the 120, I also owned a Cessna 172, a 1975 model, from 1975 to 1984 and flew it more than 2000 hours during that period. Yes, it was a nearly new demonstrator and since my income was low at the time, it’s proof that new general aviation aircraft were once more affordable than they are today. I was based at a 1600-foot strip in Massachusetts, which was adequate for the 172.

Most of my trips were throughout New England, but the sweet spot and maximum-distance regular flight was to Washington, D.C., a straight-line distance of 330 nm. This route was made necessary by my job at the time. In 1983, I flew 12 round trips to Washington National Airport (KDCA) in the 172, averaging 104 knots groundspeed (typical true airspeed was 114 knots). In this process, I discovered that I beat the airlines almost every time when considering door-to-door travel. Living across the street from the airport made this possible, since I could avoid the hour-long haul to Boston’s General Edward Lawrence Logan International Airport and the hour or two before flight drill. These were also the innocent, pre-9/11 days when I could swoop into National Airport, pay the five-dollar landing fee and be at my appointment in minutes.

Performance is relative
Flying the 172 on those routes convinced me that simple airplanes can meet many transportation needs, including occasional forays beyond the airplane’s normal practical radius of 300-400 nm. My longest day in the 172 occurred in 1983, when I flew 14.3 Hobbs meter hours (about 13:15 in the air) from Massachusetts to Tulsa, Okla. With an average 25-knot headwind, my average groundspeed over the 1186 nm was 89 knots.

However, I did cross half the continent in a single day, a remarkable capability for such a simple airplane.

The downside of this exercise is obvious. My risk was elevated simply because of the fatigue this created, especially in my 172, which had no autopilot. Mitigating the risk on that day was a co-pilot with a fairly new private certificate. She did an excellent job keeping us on track. The first two legs of this day were in IMC conditions, but the last two were in good VMC. This allowed me to nap a little and reduced the physiological risk factors.

Nevertheless, I would never conduct a similar flight today, even with an autopilot. It isn’t just age, but rather an appreciation for risk that wasn’t as much a part of my thinking back then. The fact that risk management was never part of my initial training also factors into the equation. As slow as I may be, I eventually “got it,” and I now spend a lot of time for clients trying to make sure that the next generation of pilots has a better appreciation for these subtle kinds of risk.

Performance and risk
Of course, Cessna’s 172 Skyhawk is a safe, solid airplane when used as it was designed. But there are real issues regarding performance limitations of SFGAs when used for serious transportation. My previous example of a long trip in a 172 masks the performance limitations these airplanes have, and how elevated risk is a tangible factor on many transportation missions.

These risks can be generated throughout the airplane’s performance envelope, especially in the following areas.

Takeoff and Climb: The airplanes in mind generally come with 150- or 160-hp engines as stock equipment. At gross weight, these aircraft will struggle with takeoffs and climbs under high density-altitude conditions. Under extreme conditions, you could be setting yourself up for a controlled flight into terrain (CFIT) accident.

Even though the airplane may get off the ground, it may not be able to climb out of ground effect or, if it does, the climb rate may be anemic. There is a long list of CFIT accidents that are testimony to such hazards, even for more-advanced but limited-performance aircraft (see sidebar).

To ensure acceptable performance in my 172, I often limited takeoff weight. Although always a little below gross, with two people, baggage and full long-range tanks, I also often departed with less than full fuel and modified my departure route. This strategy worked well as I flew it to locations such as Jackson Hole, Wyo.; Bryce Canyon, Utah; Stanley, Idaho; Taos and Angel Fire, N.M.; and Aspen, Colo.

Operational Ceiling: Even if you can safely take off and climb out from high density-altitude situations, your direct route might be blocked by very high terrain. I often found this to be an issue while operating my 172 in the intermountain West. When flying the Mooney 201 and Bonanza V35Bs I later operated, it was seldom an issue. With the Mooney and Bonanzas, I could strap on my portable oxygen and climb to 15,500 or 17,500 feet—even without turbocharging—for the eastbound trip out of the mountains, flying nearly a direct route.
True, limiting the load on high-performance singles helps make this performance possible, but if the capability isn’t there to begin with, any attempts to force the issue likely won’t end well.

My 172’s performance, on the other hand, often required a circuitous route out of the mountains. For example, my logbook remarks for a 4.6-hour flight on June 15, 1979, from Aspen, Colo., to Omaha, Neb., reads “14,000 feet via Gunnison, [Monarch] Pass, then 11,500.” The 172 struggled to get to 14,000 and I maintained it to get through the pass (at 11,312 feet) before slowly descending to 11,500 for the rest of the flight.

Range vs. Payload: Another issue affecting fixed-gear singles is their fuel capacity, which comes into play for any long-range mission, regardless of the terrain. My 172 had long-range tanks of 48 gallons usable, but most 172s of that era only have 38 gallons. The Warrior and other similarly powered models in the Piper PA-28 family also have 48 gallons usable as standard.

There is a trade-off that must be made in these airplanes when it comes to range vs. payload. If you find a need to fill all the seats and carry some baggage, then you may have to reduce the fuel load to an impractical level. This is further restricted if you are operating IFR and must consider the need for a legal alternate. From a risk management point of view, this could play out if you have to deviate from your route to circumvent convective activity or other weather and jeopardize your already meager reserves.

Look at it this way: If you only have, say, 50 gallons total usable fuel, and you offload a mere 120 pounds for an extra person—as if the typical passenger will weigh only 120 pounds—you have only 30 gallons remaining. At a nominal 10 gallons for the first hour, plus eight for the next, you’ll have only 12 available after two hours, and likely will be looking for a place to top off. Limited endurance means reduced flexibility: you simply don’t have the gas to fly to your destination, then to an alternate, plus another 45 minutes.

Icing Conditions: If you encounter inadvertent icing conditions in a 172 or a Warrior—or even a more modern Cirrus SR20—your performance limitations may affect your ability to climb or even hold altitude. This is a problem also in a Bonanzas, Skylanes and Centurions, Mooneys or an SR22, but their excess horsepower can buy more time as you hasten to exit the icing conditions, your only real defense in a non-icing protected aircraft.

Equipment-related
While all airplanes have a performance envelope that limits their safe utility at some level, basic fixed-gear singles have the tightest limits when considering their usefulness as transportation machines. Nevertheless, there are some ways you can mitigate the performance-related risks while maximizing safe utility.

Power: With between 145 and 160 horsepower, small fixed-gear singles have definite performance limitations. A simple expedient to improve this is to look for an example, or upgrade your current airplane, with a larger engine. The 172 and Warrior can both be easily upgraded to 180 horsepower, for a price. Also for a price, you can buy a late-model Cessna 172S, which were offered beginning in the late 1990s and come with 180-hp engines.

For the Piper, you can bite the bullet and pay more for a 180-hp Archer or the predecessor Cherokee 180. Some of the 180-hp conversions come with gross weight increases, while others do not. If the latter is true, you may suffer an increase in empty weight and a decrease in useful load. Your risk management abilities will again be needed to balance these out and determine the net improvement in performance.

Range: The Cessna 172s built between the 1960s and the present have between 38-40 gallons of usable fuel as standard. Try to find a model with long-range tanks, which provide 48-50 gallons usable. There are also some aftermarket options for installing additional fuel capacity.

If you combine long-range fuel with an engine upgrade, and don’t get a gross-weight increase out of the deal, your cabin payload will be further diminished. Your need to balance range vs. payload will be continuously tested. But popular aftermarket engine conversions often come with a gross weight increase, depending on the airframe.

Avionics: Many fixed-gear singles from the ’70s and ’80s did not come with autopilots. This is not as critical in these airplanes as it is for a Cirrus, Bonanza or Mooney. The 172 and Warrior are stable platforms and so the potential for loss of control, say while in the soup, is less. However, an example with an autopilot can greatly reduce your fatigue on those long days when you’re trying to put some miles behind you while fighting a headwind.

Performance Proficiency: The 172, Warrior and similar airplanes are as basic and easy to fly as they come. However, your ability to fly to precise speeds will be important when you’re trying to milk a little rate of climb above 10,000 feet. Spend some time with the pilot operating handbook so you are familiar with the best performance speeds for takeoff and climb.

External pressures: You must allow for more time when trying to get someplace. Remember that all winds end up being headwinds on a round trip, and your fixed-gear single will lose a higher percentage of its cruise speed than a Bonanza or SR22 will in the face of a 30 knot headwind. Plan accordingly and build in an extra time cushion when you’re trying to get to a scheduled meeting.

Indictment?
Are we saying the average SFGA isn’t a serious traveling machine? Yes, we are. They have their place, their purpose and their uses, and they do many things extremely well. But one of them isn’t serious cross-country transportation on a schedule. For that you need something faster, with longer legs and better all-around performance.

The good news is you can rent what you need, or find a nearby club with some traveling airplanes. Even better news is that now is a good time to buy a cross-country airplane, thanks to high fuel prices.

Yes, you can safely use a 160-hp-or-less airplane as a traveling machine, but there are many compromises. Those compromises can increase your risk unless you take the appropriate steps to minimize them.

Your Simple Single Isn’t A Good Cross-Country Machine

We’ve all flown simple fixed-gear airplanes (SFGA), whether in training, for recreation, an afternoon at the beach or a morning at a fly-in pancake breakfast. They’re pretty good for things like that, when there’s no weather or real schedule, and not much territory to cover, and generally are comfortable and capable when used in this fashion. Once we want to expand our range and visit new locations, their shortcomings become highlighted. Here are a few:

They’re slow
On a 75-nm flight to a pancake breakfast, the difference in elapsed time between one airplane with a 150-knot average groundspeed and another that can muster only 100 knots isn’t very stark: The slower airplane takes 45 minutes while the faster one needs only 30. But a 300-nm trip takes a full extra hour in the SFGA. Although the slower airplane also is more easily impacted by weather, your primary risk management concern should be fatigue.

They Have Short Legs
In any kind of serious IFR flying, range and endurance are sought-after characteristics. Together, they offer flexibility and options, and having them often can be the difference between a “doable” flight and one better accomplished on an airline. Deviating around convective weather, diverting to alternates and dealing with headwinds all consume fuel. If you have only four hours of cruise fuel, a rather common 25-knot headwind cuts your range by 100 nm.

They can’t climb
An airplane’s climb performance is based, in part, on how much power is available in excess of that required to maintain level flight. If it requires 100 hp to fly straight and level at VY, a 150-hp airplane has only 50 hp to play with, and it loses a little bit with each thousand feet of altitude. A 250-hp airplane, meanwhile, might need 125 hp at sea level at VY, but it starts the climb with another 125 hp available.

Typical performance-related CFIT accidents in SFG airplanes
On May 28, 2002, a Cirrus SR20 departed the Angel Fire (N.M.) Airport (KAXX), which is at an elevation of 8380 feet and situated in a “bowl” surrounded by the Sangre de Cristo Mountains. Although under gross weight, the aircraft impacted rising terrain and the solo pilot was killed. Density altitude at the crash site was calculated to be 11,807 feet.

A similar accident at Angel Fire had occurred two years previously, on June 25, 2000. An older Cessna 172, with a 145-hp engine, took off and impacted terrain only a few miles away, where the prevailing density altitude was over 11,000 feet. Two of its three occupants were killed.

Another 172, a later model with 160 hp, departed eastbound from Aspen, Colo., on October 23, 1999. The airport is at 7815 feet elevation. The aircraft impacted the terrain a few miles east while trying to squeak through the 12,095-foot-high Independence Pass. Density altitude at that accident site was over 14,000 feet. The pilot was killed and the two passengers were severely injured.

These accidents are more dramatic because of the challenging terrain where they occurred. However, there are plenty of examples of such performance related accidents close to sea level, where the combination of full loads (or over gross takeoffs), minimal excess horsepower, and pilot ignorance of optimum performance numbers and/or basic risk management conspired to create the accident backdrop.

Yes, Comanches, SR22s, Mooneys, Centurions and the like also have been flown into the ground in high density-altitude situations. And, SFGAs aren’t automatically falling out of the sky every time they encounter high and hot conditions. But the margins get wider when the airplane has better capabilities.

Does More Horsepower Mean Less Risk?

No, of course not. Especially if you’re a conscientious pilot who flies your flivver on good-weather days or over well-known routes at relatively low altitudes. And that same SFGA can be used to fly hard IFR outside of icing conditions and away from terrain where they can’t achieve the necessary minimum climb rates. You probably won’t endear yourself to anyone if you show up in one at KLGA on a Friday evening, but you knew that.

More horsepower means a lot of things when trying to meet a schedule with a personal airplane. They include a reasonable expectation of being on time, even if the winds are a bit stronger than forecast, or of being able to carry what you need for the trip.

It means you might be able to climb with the same amount of ice that would leave less-powerful airplanes in distress. It means you can more easily outrun thunderstorms, or get around them. And it also means you’ll be less fatigued when you get to your destination.

Robert Wright is a former FAA executive and President of Wright Aviation Solutions LLC. He is also a 9600-hour ATP and holds a Flight Instructor Certificate. His opinions in this article do not necessarily represent those of clients or other organizations that he represents.

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