Cessna 170 - Price, Speed, Fuel Burn & Specs

‍The Cessna 170 is a jack of all trades. From bush to cargo flying, it’s robust yet nimble. This guide contains all you need if you are considering a C170.

Cessna produced 5000 170s between 1948 and 1956, with 2500 still flying today. An original C170 with 3800 hours TT, costs $38,000 while a modified one can be about $190,000. With a useful load of 650 lbs, a cruise speed of 114 kn and the ability to land just about anywhere, the C170 is versatile.

As a CFII, the Cessna 170 family is one of the main aircraft types I use to teach my students (alongside the Cessna 150/152, Cessna 172 and a few others). As a passionate avgeek, the C170 is one of my favorites owing to its simplicity, reliability, and above all else, its safety.

‍Background

The Cessna 170 is a later version of a previous model, the C140, and a precursor to the ubiquitous Cessna 172. Designed to bridge the gap between the two-seater C140 and the larger five-seater 190 Businessliner, the Cessna 170 came with four seats and an elongated airframe. Other than that it was basically the same as the C140.

Built between 1948 and 1956 Cessna produced three variants. The 170A came in 1849, a year after the original, followed by the 170B in 1950. All three variants have regular, ski plane, and seaplane versions, making them perfect for almost all types of potential operators.

While all three models are taildraggers, it is fairly easy to tell them apart if you know what to look for. The C170B is the only one of the three that has a wing dihedral. A dihedral is when the tip of the wing is a little higher than the root of the wing. This does change its roll stability and you can feel it when you fly the plane.

A Cessna 170A can be distinguished from its predecessor by observing the wing. The C170 has a constant chord wing while the C170A has a slight taper. Neither has a dihedral like the 170B.

The wing of the C170 is covered by fabric instead of the typical metal we are used to in today’s planes. It’s the reason the C170s are referred to as a ragwing. The C170A and B variants have regular metal-covered wings.

Specs

Flight Characteristics

As both a taildragger and a high-wing aircraft, the Cessna 170 has a center of gravity that is slightly aft of the aircraft’s center of lift. It is one of the main characteristics that give the aircraft its docile handling characteristics.

Having a wing made of fabric reduces the moment of the wing and makes its roll characteristics about the longitudinal axis crisp and agile. Even its stalls are gentle, breaking without the tendency to roll one way or the other. Uncoordinated stalls in the C170 are docile, more so than in the C170A and B, which do not feature fabric wings.

The fan-shaped rudder provides sufficient authority to counter steep power-on ascents and power-on stalls. There is enough rudder authority to counter any P-factor and torque the engine can create.

Only the skin of the wings uses fabric. The rest of the aircraft is covered by aluminum, riveted to ribs, and strengthened by spars. It is the tried and tested semi-monocoque structure that provides sufficient rigidity balanced with flexibility.

When buying the Cessna 170, make sure to have the fabric inspected and budget for new fabric down the road if not immediately after taking possession. Replacing the fabric will cost in the region of $10,000.

Most people who buy a C170 in the used market do it because of its fabric wing, and if you are not looking for that, you will be better off choosing the C170 A or 170 B that have all-metal wings. The Cessna 170 has the closest handling qualities to the C170 compared to the C170B.

If you purchased a Cessna 170 and decided to modify it to all-metal wings, it is possible. There are mods and STSs for that, but it will increase the weight and reduce the performance of the aircraft. By some reports, be prepared to take a hit of up to 15 knots at 75% power.

The 170A when Cessna decided to upgrade the wing, but keep the rest of the aircraft unchanged. To deal with the altered lift profile and weight limitations by the added all-metal skin, they changed the wing by introducing a slight taper and enlarged the flaps to allow the same approach speed to handle the added weight.

The strengthening of the wings by using metal sheets also allowed for an increase in the size of the fuel tank. This increased fuel capacity from 37.5 gallons to 42 gallons allowed the C170A to have the same performance as the Cessna 170 even with the added weight. To keep all things the same, the empennage was also modified with the addition of a dorsal fin.

To further improve an already successful design, Cessna enhanced the aerodynamics and released a new model, the C170B. Two changes were of particular note. Both had a significant effect on the flight characteristics across the flight envelope of the aircraft.

The first was the addition of a dihedral angle to the wing, as mentioned earlier. The second was the addition of semi-Fowler flaps.

Fowler flaps allow for larger wing surface area as they are tucked inside the wing for most of the phases in flight and used in landing when the flap juts out of the wings and lowers itself. This alters the wing’s camber and area simultaneously.

What you will also find is that the C170B behaves very differently. With full flaps, it is not advisable to maintain a high angle of attack as the horizontal tail is shrouded by the larger wing surface and loses effectiveness.

But the change in the wing area and camber allowed it to land in much shorter runways, shaving off more than 200 feet of landing distance depending on the headwinds it encounters.

The original engine was powerful enough to make this an everyday transport for personal use but it was not the fastest it could be. Cessna chose the Continental O-145 engine that generated 145 horsepower but built an airframe that could handle more. That's the reason it can easily be upgraded to a 180-hp engine.

While the C170 and 1C70A had O-145 engines, the C170B came with the much more powerful O-300 engine. The change in the model didn’t change its performance as it was just a model number change for the same identical engine, done by Continental. Continental changed its nomenclature to have significance with the O indicating that it is normally aspirated and the 300 meaning that it displaced 300 cubic inches.

Price

The price of the Cessna 170, whether it is the original model, or the subsequent A or B model. Varies widely. It would be amiss to set a price and a range and leave it at that without explaining.

Because the first Cessna 170 rolled off the factory floor in Wichita back in 1948, more than seven decades span across its birth and our present. In that time many have fallen to the wayside while others have just become run down. There is even precedence for C170 models that have been sold for $12,000. But that’s not the norm.

When Cessna first introduced the C170 in 1948, it sold for $5,995. Four years later, when the 170B was introduced, it was sold for $7,245. But a quick survey across the typical used aircraft websites reveals prices ranging from a shade under $40,000 for aircraft with original avionics and an out-of-time engine to $60,000 for good condition models.

The average time on the airframe for the C170, across all three variants, is 4,000 hours. The low number comes from the methodology of the calculation revealing that with that number, the almost seventy-five-year-old aircraft only flew 53 hours a year.

That number, while mathematically accurate, does not represent the bulk of what is out in the flying world. Best estimates of C170s, C170As and C170Bs suggest an average use of 200 hours a year over the last seventy years. It is also fair to keep in mind that aircraft of this vintage are not priced based on age and time flown, it is more about the history it represents.

Most Cessna 170s that are on sale have had major airframe work done, rendering the metal that it currently carries as not the same one that left the factory. But if you do find one, still with all the original material as it was when rolled off the factory floor, then the condition determines its pricing. One in mint condition, with low time, can be located using a broker but will likely set you back more than $250,000.

For what’s advertised on the market, the highest median price for one that is not considered a collector’s item averages about $120,000, and it is usually found to be the C170A. The C170B is the second highest in pricing, followed by the original Cessna 170A.

The differences in pricing can be attributed to the fact that the Cessna 170’s fabric wing is not desired by current buyers in the market, and the flight characteristics of the C170B are not seen as good as the 170A. There may also be the reason that

Operating Cost

The methodology for determining operating costs should be consistent when you own or plan to own an airplane. Everyone seems to subscribe to different methodologies and philosophies. Some aircraft owners look at bank payments as part of the hourly costs and even include depreciation, or they fail to include a reserve for overhaul expenses.

How you determine operating costs should depend on individual circumstances and there is no right or wrong way. There is, however, a general method you can use to account for the aircraft over the time you own it. Split the costs into fixed costs and direct operating costs and always consider that the resale will be at a loss - then amortize that value.

Direct Costs are costs you will incur based on the number of hours you fly the airplane. Fixed costs are costs you will incur to own the airplane. This will continue even when the plane is on the ground.

Direct Operating Cost (DOC)

The biggest chunk in DOC is the cost of fuel. Right now it's about $7.6 at my airport. That has changed back and forth over the time I’ve been flying. But at 9.6 gallons per hour at 75% power, the price of fuel alone is $73 per hour. But there is a lot more to that.

Another cost that you must consider is the cost of engine oil. The O-300 easily burns about 3 quarts for every four hours of flight. And that burn rate differs from plane to plane. If you consider that the cost of a quart is $10 then four hours of flight will cost you $30 in oil. This works out, on average, to be ($30/4 hours) $7.5 per hour.

As far as maintenance is concerned, if you are not renting this out, you are only required to run an annual and do the overhauls. Annuals typically cost about $500 per year while an overhaul costs $28,000. If you recall listed above, you will see that the Continental O-300 engine needs to be overhauled at 1200 hours.

Putting aside a small amount of money for overalls is a wise step in owning an aircraft. $28,000/1200 hours works out to be $23.3 per hour.

As for the annual maintenance, that’s a little nebulous to decide. While you still have to conduct an annual on your C170 even when you don’t fly it all year, it feels like it should be part of the fixed cost segment, but when you do fly the Cessna 170, you will see that dormant years cost a little less than active years. So I put this in the fixed column for hardly-flown aircraft and in the variable column for actively flown ones.

The total Direct Operating Costs (DOC) for a Cessna 170 (including the A and B variants) is $73 for fuel, $7.5 for oil, and $23.3 for the overhaul fund. That’s $103.8 per hour, excluding fixed cost allocation.

Fixed Costs

The main things under fixed costs that you have to consider are tie-downs and insurance. The former is about $360 a year where I am and insurance, depending on what you’ve insured your hull for, can run anywhere from $3000 a year to about $7,000 depending on the mods and additions you put on it.

In the fixed cost column, you should have a rough estimate of how many hours you plan on flying the 170 in a year. If you are flying it for yourself and the family, 400 hours a year is not too bad a guess. At 400 hours a year, the annual you will have to spend will typically be about $700.

If I assume that a $50,000 Cessna 170A will only be worth $47,000 in three years' time, then I can assume a $1000-per-year depreciation. Some folks chose to include the potential depreciation in the cost of flying, but it doesn’t make a huge difference.

After all, you have already spent the money and bought the plane, unless you believe that when the time comes to sell the plane you will still have an overhang with the bank, then including the depreciation number in the hourly cost will create a small fund that you can use to address that overhang.

The total Fixed Costs you would have to include in your cost calculations would be $700 for annual maintenance, an average of $5000 for insurance, and $360 for tie-downs. You could also add about $1000 for unscheduled maintenance that crops up every now and again. That would add up to $7060 per year. Assuming you flew 400 hours every year that would be an hourly cost of $17.65.

If we add this to the DOC that we calculated above, it tells us that to operate a Cessna 170 which we purchased for $50,000 and plan to sell in three years, flying it 400 hours a year would cost $121.45.

Speed

The three variants differ slightly in speed. The Cessna 170 differs between fabric-covered wings and all-metal wings. The additional weight not only reduces speed but increases the drag due to the alteration of the center of gravity.

Approach speed when crossing the threshold on landing is a major factor in flying this aircraft. You have to fly it by the numbers as taildraggers typically have the propensity to cartwheel if incorrectly handled.

In slow flight, configured clean, the C170 begins to buffet at 55 knots. But the buffet is light, just a slight addition of power remedies it. But if you continue to pull back on the yoke in an attempt to maintain altitude, the stall breaks at 50 knots or lower. There is a STOL kit that you can add to the C170 that reduces the stall speed considerably making it much harder to get the plane to stall.

In the landing configuration, the C170 stalls at 45 knots. But by this point, the rudder is quite mushy in the 170B. Not so much in the earlier models. If you plan on practicing stalls in the C170B don’t go past thirty degrees of flaps.

In terms of cruise speed, the Cessna 170 follows Cessna’s design philosophy: cheap but slow.

With a typical cruise of 120 knots at 75% power the aircraft will fly for 5 hours leaving about half an hour worth of fuel left in the tanks. In a no-wind condition on a standard day that works out to be about 500 miles.

The cost to fly for 5 hours is $608. With 668 pounds of cargo, including yourself as the pilot, the cost to fly 688 pounds across 500 miles is 92 cents per pound.

Fuel Burn

Most pilots who fly the C170 like to keep their altitude up at 6000 feet. Aside from the typical reasons for flying smoother air, the engines can be leaned out to provide longer endurance while still providing enough speed.

The 170’s fuel burn, as with all normally aspirated aircraft, is highly dependent on the altitude it flies at. Flying at 6,000 feet with 75% power requires rpm to be set at 2600. If the fuel flow is not adjusted and the engine runs at full rich, you will consume 11.1 gallons per hour.

If you lean it out according to the EGT, find where the needle hits peak EGT then dial it back two notches. This will give you 9.6 gph. On average it will result in approximately 110 knots of True Airspeed.