Plane Speed: How Fast Do You Need To Fly?

Speed is sexy, it's true. So, go ahead, admit it. When you read all of those pilot reports, you skim them, looking for the cruise speed, then go back and read the rest. It’s a natural thing. We all love the idea of going fast. But how fast is fast? And is there such a thing as fast enough?

Even though the aviation world is largely one of knots and not miles per hour, when it comes to speed, some of us still think in terms of that good old mph. For years, manufacturers were the worst offenders. Why? Because 200 mph looks a lot faster than 175 knots, even though they're just decimal points apart in actual value. So, within general aviation, 200 mph looms as some sort of speed barrier for single-engine aircraft—if you’re cruising at 200 mph or better, you’re really making tracks. At least that’s how it used to be. These days, 200 knots might well be the new Valhalla. But we’ll stick with mph for this discussion. We’ll all feel faster for it.

The big question remains. What does speed mean in real terms? What kind of advantages do those fast movers enjoy, and is it worth what you have to pay for it?

The answers are, there are a lot of advantages, some big, some not so big, and the costs can be great. Can they be too great? Good question. Let’s look at some real-world cases.

Let’s say it’s a 500-mile trip, which is average for most pilots. What’s the difference between cruising at 160 mph (138 knots, something that a clean Cessna 182 would make) and 200 mph (174 knots, something that a late Beech Bonanza would perform)? It doesn’t take a math wizard to see the Bonanza saves 36 minutes. Is the time worth what it costs to save it?

Airplanes as fast as 200 mph always have the increased maintenance of retractable gear (Cirrus and Lancair excluded) and big motors, and almost always have higher acquisition costs. Within the traditional general aviation fleet, however, there are actually only a few airplanes that can honestly claim to cruise 200 mph. These include later Bonanzas, a few Bellanca Vikings, the old Meyers 200D, the Mooney 200 series, some Cessna Centurions and some specialty birds, like the Siai-Marchetti SF-260. Of these, none is cheap, although the Viking and its wooden wings has lagged behind the rest in cost. The big question is how much time is extra speed actually saving you, and is it worth all the hassle? (See the “Time Versus Speed” chart.)

If you’re willing to give up those 36 minutes and fly 150 to 160 mph, do you gain anything? The most obvious advantage is that it costs less to get into the game to begin with. Even though the tried-and-true Skylane is probably the most expensive airplane in its category, it’s still cheaper than most of the fast movers, and early square-tail Skylanes are screaming bargains. But what if you desperately want the bragging rights that go with a 200 mph cruise speed? Or what if you really do need that speed on long trips? Is there such a thing as cheap speed, and how do we evaluate it?

Maybe what we should be talking about here isn’t raw, dollars-be-damned speed, but miles per dollar—how much does each mph cost us (and the cost has to be defined as not only the gas being burned, but also what it costs to get into that seat in the first place). Plus, we need to apply some kind of factor for maintenance, which is going to be a pure guess.

When you start talking speeds over 160 mph, you’ve automatically stepped into the land of retractable gear (again, excluding Cirrus, Cessna’s TTx and a number of lesser known homebuilts) and, as you move up past 180 mph, the pickings start to get pretty slim. Let’s look at some candidates and see how they stack up when you compare their stats (see “The True Costs Of Speed” chart). Be advised, however, that there’s some Kentucky windage here in terms of fuel burn, and we’re basing our speeds on published specs that often are questionable. Still, it gives us something that can put airplanes in positions relative to one another. (Please note that the pricing on these charts is based on typical used prices from about 10 years ago. As a guide, in most cases, you should add between 25% and 50% to the purchase prices we have listed. Bear this in mind in regards to other cost figures we cite here.)

The physics behind fuel efficiency haven’t changed in the last 10 years, thank goodness. Notice in the chart how the fuel efficiency clusters around 11 to 12 mpg until you hit the Mooneys, when it jumps up to 20 mpg. That’s because Mooneys give up some cabin comfort to keep the frontal area down, plus they have worked really hard at making themselves aerodynamically efficient at higher altitudes. The net result is that they’re delivering higher speeds with smaller motors (200 hp), which translates to better overall efficiency. In fact, the small, but fast Mooneys are almost a match for the lowly Taylorcraft (5 gph) in the efficiency department. Additionally, some of the early, small Mooneys are not as fast as the later ones, but are relatively low-priced (Skylane prices) and still deliver 170 to 180 mph on 180 horses with 9 to 10 gph fuel burns.

Another way to look at the speed is how much we have to pay for each additional mile per hour of speed when buying the airplane. Even when using Bluebook aircraft values as comparisons, which are usually low, it shows that airplanes like the Bonanza, which are much larger and more luxurious, but nowhere nearly as efficient as the Mooneys, command higher prices. Therefore, on a dollar-per-mph basis, they’re much more expensive ($785 per mph versus $400 per mph), plus they’re way down in the fuel-efficiency curve. So why do people buy Bonanzas over Mooneys? Probably because they like the comfort and don’t object to burning a little more gas. So, once you’re going fast, other factors apparently count, as well.

Range: The Great Equalizer, Up To A Point
With all this talk of speed, there’s one other factor that has to be tossed into the decision equation: range. How far will it go without stopping at a gas station? When we’re talking 500-mile trips, that’s not usually a factor because just about everything has at least 500 sm of range, but a funny thing happens when we stretch that trip out to 1,200 miles. Suddenly, haulin’ ass isn’t as important as haulin’ gas.

Let’s say you’re flying a 300 hp, 1980 Bellanca Viking that actually does deliver its advertised 202 mph cruise speed. Its spec sheet says its range is barely 600 miles (and we’ll bet that isn’t at 202 mph). So, to safely make 1,200 miles and still have some reserve, it would have to stop twice to get gas. The actual time in the air would be 5.9 hours (probably longer, since spec sheet range numbers usually are at economy settings, but speed is quoted at 75%). Two fuel stops, however, are going to add 1.5 hours (45 minutes per stop, which is conservative) for a total of 7.3 hours. For a trip of 1,000 miles, the Bellanca suddenly looks good again. That second fuel stop on a long trip is a killer.

Still, back to that hypothetical 1,200 trip. Now, let’s say your lowly Cessna 182 is plodding along at 160 mph, but burning significantly less gas. More importantly, it’s a newer model with 88-gallon tanks, which, according to the specifications, gives 913 miles of range. So, it easily can make it with only one stop. Seven and a half hours of flying, plus 0.7 of ground time, gives you 8.2 hours of total elapsed time. So, the much faster Bellanca Viking only got there 55 minutes faster. But are all of those things a really big deal on such a long trip?

Often they’re not, but when it comes to multiple legs, even short ones, speed can make a huge difference. A flight of 400 miles won’t require a fuel stop for any of these planes, but the time saved flying a much faster airplane will translate into not just one faster trip, but potentially three, or on a long, busy day, maybe four. Getting back home a couple of hours earlier, or maybe just getting back home at all instead of having to hotel it at the last stop, is worth a lot.

Now, let’s toss in aftermarket auxiliary tanks so we can be flying an earlier, and much less expensive, Cessna 182 (or Cherokee 235 or…). This extra 23 gallons gives the early airplanes another 1.7 hours for a total range of about 800 miles. So, now we’re flying an airplane that may have cost us as little as $45,000 (a fixer-upper, like a 1959 C-182), but we came in only 55 minutes behind the blazing Viking after a daylong trip. If you do a lot of long cross-countries, installing auxiliary tanks could be considered the best and most effective speed mod.

How about comparing the Cessna Skylane to a 300 hp A36 Bonanza? The Bonanza costs at least three times more than the C-182, but the Bonanza can make the 1,200 miles with one fuel stop so it would get there 1.5 hours quicker. Okay, so after a 1,200-mile trip, the Bonanza folks will be in the hotel while the Cessna is taxiing in, but the Cessna’s cost of operation is pennies compared to the Bonanza’s insurance, cost of acquisition and maintenance. You have to decide what that extra time is worth to you. Is it worth an extra $100,000 to $200,000 in acquisition and at least twice the support cost to save an hour and a half on that 1,200-mile trip you take only every other year? On the other hand, if you’re routinely flying trips that long, speed becomes a real factor.

Turbos Make A Difference
An aircraft equipped with a turbocharger is always going to offer increased speed and fuel efficiency over its normally aspirated counterpart because it will hold its power to a higher altitude where it gets really fast and burns less gas. The only downside to turbochargers is that they increase the maintenance and acquisition costs, and some require a bit more pilot technique.

In terms of performance, a blown A36, as an example, is supposed to cruise at 218 mph (190 knots) compared to a normally aspirated version at 194 mph (169 knots), and a TC Saratoga will do 203 mph (177 knots) versus 181 mph (158 knots), while the range goes up 65 miles to a whopping 950 miles. (See the “Turbocharged Speed Comparison” chart.)

It might be worth noting that while we don’t normally think of any version of a Skylane as being a speed demon, the TC182RG runs right at 200 mph. Also, the TC210 Turbo Centurion series is a real sleeper at 226 mph (197 knots) while the pressurized P210R is capable of running an unbelievable 243 mph (212 knots) at altitude. Now, that’s really getting down the road!

So, What’s Fast Enough?
The concept of “fast enough” is strictly subject to personal definition. For some, there is no such thing. For others, flying is its own reward, and the longer it takes to arrive, the happier they are. For most, however, the decision involves the irritating interplay between wants, needs and financial capabilities: We always want speed, but do we really need it and can we afford it? Okay, so maybe we don’t really need to go that fast, but did you ever notice how much better you feel when the GPS is giving you a ridiculously high groundspeed? So, maybe speed is just what the doctor ordered: Increase your quality of life by going faster. How’s that for rationalizing?

Are you looking for cheap ways to fly faster? Check out our article Speed Without Mods.