Cessna 170

The great-granddaddy of a sizeable chunk of the worlds single-engined aircraft, the 170s basic airframe is still being produced as the Skyhawk.

Its a good-performing, honest four-seater and also a lot of fun to fly. Like any other taildragger, though, it can bite. And though 170s still are quite affordable, prices continue to climb.

Cessna built 5,136 of the airplanes in a nine-year production run that ended over 40 years ago. But time has taken a toll on the population. Today, considerably less than half of the airplanes are still flying; and accident records show that ground loops and hard landings are continuing to thin out the 170 fleet at quite a clip.

Still, there are many who turn a veiled eye on the taildraggers safety record and dismiss the tricycle-gear 172-the 170s successor-as a giant step backward in airplane design. Attesting their viewpoint are the popularity of tailwheel conversions for 172s and the rapidly increasing prices for Cessnas original light four-seater. Cessna 170s typically are fetching substantially higher prices than other comparable four-seaters of the same vintage, including the much faster Piper Tri-Pacer. Also, the price tags on many 170s outstrip those on vastly better-equipped and newer 172s.

Though they cannot be classified as bargains, 170s still are affordable family-movers. The top average retail from the Aircraft Bluebook is listed at $33,000 (with a note that the price varies with the quality of restoration work). Owners characterize operating and maintenance costs as relative pittances, and they like to compare the performance and load-carrying capabilities with new four-seaters that cost far more. However, it is inevitable that the airplanes can show signs of their age, in the form of corrosion and fatigue. And though some parts are hard to find, help in the care and feeding of Cessna 170s is available from a supportive owners group.

History
When Cessna started building 170s in 1948, it had only four other airplanes on its assembly lines. They were the svelte, two-seat, 85-HP 120 and 140 models, and the big, four-seat, radial-engine 190 and 195. The 170 actually is a stretched, four-seat version of the 140, powered by a six-cylinder, 145-HP Continental C145-2 engine (later to be redesignated the O-300A) and a two-blade McCauley propeller.

The original 170, built only in 1948, can be distinguished from its descendants by its fabric-covered, constant-chord, round-tip, V-strutted wings and by the absence of a dorsal fin. Inside the wings are three 12.5-gallon tanks (one in the left wing, two interconnected in the right), providing a usable supply of 33.5 gallons.

In 1949, the Model 170A made its debut with a dorsal fin and all-metal wings supported by a single strut on each side of the fuselage. Outboard of the struts, the wings taper out to their squared-off tips. The A-models flaps and ailerons are a bit larger than the 170s, and the hinged flaps can be extended to 50 degrees (whereas the 170s flaps are limited to 30 degrees). The dorsal fin is identical to the one on the Model 195 and was added, supposedly, to improve directional stability. There’s only one fuel tank in each of the 170As wings, and maximum usable fuel capacity is 37 gallons.

While the original 170 is affectionately referred to, for obvious reasons, as the ragwing, the A model sometimes is called the straight wing. That’s because unlike the 170, which has about one degree of dihedral, and the 170B, which has nearly three degrees, the 170A has no dihedral.

Para-lifter
In 1952 Cessna introduced the 170B. This model has what Cessna called Para-lift flaps-relatively large, slotted, semi-Fowler designs originally used on the Model 305 military observation plane, which blue-suiters dubbed the L-19 Bird Dog. Early B models have only four flap settings (zero, 20, 30 and 40 degrees). Those built after 1954 have an extra notch for 10 degrees of flap, which many pilots favor for takeoff.

In addition to being cranked up to nearly three degrees of dihedral, the 170Bs wings have more twist than their predecessors. The B model also has control balance weights that make its elevators a bit lighter to the touch.

Upper engine cowls on 170-series airplanes built before 1953 are hinged; those on later models are full pressure types with fairly large hatches that open onto the battery and oil dipstick. Airplanes built before mid-1953 also have straight, interchangeable main gear legs; later 170Bs have bowed and more acutely tapered legs, which cannot be swapped from side to side. Other changes in 1953 included addition of extra heating outlets for passenger seats and a windshield defroster, and replacement of piano-key type panel switches with push-pull knobs.

Airplanes built after 1954 can be distinguished by a cosmetic touch to their windows and by a different tailwheel-steering setup. The aft portions of their rear windows are flat, rather than round, and the airplanes have cables, rather than a rudder horn/spring system, for their tailwheels.

Tri-ing times
Influenced, no doubt, by Pipers success with the Tri-Pacer (originally introduced in 1951 as a tricycle-gear option for the Pacer), Cessna introduced the Model 172 in 1956. It took only a year for the 170 to become extinct; the company already had a capable utility taildragger in the 180, and pilots took an immediate shine to the 172, buying more than 1,100 of them in the first year.

The last B models off the line differ from earlier 170s in having molded-plastic interiors, rather than cloth; an un-openable right-door window; and only one engine-cowl hatch, which opens onto both the oil dipstick and the battery. (The battery had been moved from the right to the left side of the engine compartment in 1954.)

Performance
A properly rigged 170 will cruise at 104 knots true at around 2,400 RPM (65 to 70 percent power) while burning between seven and eight gallons of fuel an hour at altitudes below 8,000 feet. Fuel can be drawn from either wing tank or from both of them at the same time (the latter is required for takeoff and landing). Direct-reading fuel gauges are located in the wing-root areas of the cabin.

Generally, book performance numbers are achievable, according to owners. But some claim the takeoff figures in 170 POHs are conservative, at best. The book indicates that, under standard conditions, a 170 will require 1,820 feet for takeoff, 2,190 feet to clear a 50-foot obstacle. Subtract about 200 feet from those numbers if 20 degrees of flaps are used for departure. However, some owners say they regularly use up about half that amount of real estate getting aloft. The POH also shows that 1,145 feet are required for a normal landing, 1,210 feet to get in over an obstacle.

Best rate-of-climb speed is 77 knots, and climb rate diminishes from a sprightly 690 FPM at sea level to a leisurely 370 FPM at 7,000 feet. The airplane stalls at about 50 knots, clean, and 45 knots with full flaps.

Comfort and loading
Visibility is excellent on the ground and in the air, due to the low panel and sloped engine cowl. Two wide doors and relatively big assist steps make it easy to board the airplane. Inside, there’s plenty of room for four people, but 170 cabins tend to be rather noisy, and even the improved heating systems in late-model 170Bs are hard-pressed to deal with northern climes.

Unlike many other single-engine airplanes with four seats, most 170s can carry full fuel, four adults and their baggage. Maximum useful load of 170s and 170As with standard (that is, Spartan) equipment is 1,015 pounds; 995 pounds for the B model. Up to 120 pounds of baggage can be carried behind the rear seat but must be loaded through the front doors, since none of the airplanes was built with an external baggage hatch. External hatches have, however, been STCed for the airplanes.

Handling
It would seem that, with the various changes made during the course of 170 production, there would be marked handling differences among the models. But pilots who have flown all three models say there is little difference.

Some idiosyncrasies arise from the different flap designs. The 170s are relatively small and limited to 30 degrees extension (at 90 MPH, max). Though its flaps are not as effective as those on its successors (which can be extended at 100 MPH), the original 170 can be slipped quite effectively. Slips with full flaps are prohibited in the A and B models, because their barn doors can block the air flowing over the tail, causing the nose to pitch down suddenly and severely. Another difference, mentioned earlier, is the lighter elevator control forces experienced in the 170B, due to its mass balance weights.

Owners seem to be split on whether three-pointers or wheelies are better for takeoff and landing. On one hand, they say, wheelies require longer ground runs and rolls, and higher airspeeds. On the other hand, the main gear legs are rather stiff, and three-pointers tend to give the tailwheel a good beating (and the occupants a good bouncing) if technique isn’t perfect or the field is rough.

Swapping ends
One long-time 170 pilot summed it up this way, The 170 is one of the easier taildraggers to land, but any taildragger will bite you. Indeed, in a comparative study of 33 single-engine airplanes a few years ago, NTSB found 170s to be involved in a relatively high rate of ground-loop accidents. With 10 such accidents per 100,000 hours of flying time, the 170 came in fourth place. At the head of the list of groundloopers was the Cessna 195, with a whopping 22 end-swaps per 100,000 hours. Then came the Stinson 108 and the Luscombe, each with a rate of about 13.

Close behind the 170 were its two-seat stalemates, the 120 and 140, with about nine ground-loop accidents per 100,000 hours. As might be expected, tricycle-gear airplanes fell to the bottom of the ground-loop list. The PA-22 Tri-Pacer placed in mid-range (15th, actually) with a rate of nearly three; the 172 was 29th with a rate of one ground-loop per 100,000 hours.

Studying more recent records, we found loss of control during takeoff or landing accounted for more than half of nonfatal accidents (40 out of 70) involving Cessna 170s during a six-year period. Though many occurred with low-timers at the controls, quite a few involved pilots with hundreds of hours in type. Also, several of the accidents involving loss of control and those involving collision with objects during takeoff or landing (there were nine of these) occurred in such formidable operating areas as country roads, rough fields and sand bars. A number of accidents were precipitated by broken main landing gear axles and wheels.

Of the 12 accidents involving either fatalities or serious injuries, four involved stalls and spins; four occurred during buzz-jobs or low-level aerobatics; and two involved continued VFR flight into instrument weather conditions (one pilot wasn’t instrument-rated, the other was but the airplane wasn’t suitably equipped). Two other pilots lost control of their 170s: one after the prop separated; one after a rusted rudder cable broke in flight.

Maintenance
Corrosion and fatigue cracks are the most frequent subjects of SDRs. Affected components include flight control cables, main landing gear support brackets, vertical stabilizer attachments, bulkheads and engine attach brackets. There was one report of severely corroded wing spars in a 170A that had been parked outside and not flown for three years.

Due to similarities between the 170 and the 172, parts are not a big problem. The International Cessna 170 Association frequently arranges to secure quantities of critical parts from Cessna Aircraft Corp. and other suppliers. A few years ago the group pooled its resources to have Cessna produce a supply of solid (ski) axles. Two other types of axles used in production of 170s were hollow designs; and service difficulty and accident reports show that they are prone to break under excessive side loading. The association also was able to bring the price of seat tracks down substantially by placing a quantity order with Cessna.

The Continental engine was designed to operate on 80/87-octane aviation fuel, which is increasingly becoming hard to find in many areas of the country, and many 170 owners have experienced problems on 100LL. Some have invested in exhaust-gas temperature (EGT) gauges for their airplanes and alleviate the problems by leaning aggressively. Others have sought relief from lead-fouling problems and the higher prices of avgas by operating their airplanes on premium unleaded automobile gasoline with STCs available either from the EAA Aviation Foundation in Oshkosh, Wisconsin, or from Petersen Aviation in Minden, Nebraska.

The 170 has been around so long that the AD picture is pretty quiet by now, though occasionally it gets hit by a shotgun directive. The most recent (98-1-6) is one such, calling for replacement of two-piece carburetor venturis with one-piece units.

Another recent AD is more significant to the pocketbook, because its repetitive: AD 97-18-2 calls for recurrent inspections of the prop.

Modifications
Nearly 100 STCs have been approved, including dozens for installation of skis and floats. Many floatplane operators have opted for larger engines. Avcon and Bush, both in Udall, Kan., offer 180-HP Lycomings and constant-speed propellers for A and B models. Turbotech in Vancouver, Wash., has a 220-HP Franklin conversion for the 170B. Flap and aileron gap seals, and complete STOL modification kits are available from Horton STOL in Wellington, Kan., and from Avcon and Bush. Davids Aviation Services in San Andreas, Calif., also offers gap seals, as we’ll as a thorough aerodynamic cleanup, complete with wheel pants, landing gear cuffs and fairings. Ponk Aviation in Camano Island, Wash., has an STC for beefed-up landing gear brackets.

Owners group
Efforts by the International Cessna 170 Assn. to secure needed parts for the airplanes already have been mentioned. In addition, the group publishes a monthly newsletter and four quarterly magazines containing tips on maintenance and safety, and conducts regional fly-ins and an annual convention. Velvet Fackeldey is the associations executive secretary: P.O. Box 1667, Lebanon, MO 65536, (417) 532-4847.

In addition, 170 owners are represented by the Cessna Pilots Assn. (www.cessna.org, (805) 922-2580) in Wichita, Kansas.

Conclusions
Tailwheel airplanes are great for nostalgia, but they do require some special skills that largely have been lost among todays pilots. Those who want a four-seat taildragger, and are willing to develop and hone the necessary skills, might want to consider buying an early-model 172 and having it converted to tailwheel configuration. This could actually cost less than buying a 170.

But the 170 is in a class by itself, and those who want the real McCoy aren’t going to be bridled by a few extra dollars here or there. Since prices are going up, purchase can be seen as a good investment. And, as mentioned earlier, a 170 is a true four-seater with performance (if not mission flexibility) rivaling that of current production singles and acquisition and operating costs putting the brand-new airplanes to shame. Too, there’s one very obvious fact: the 170 is a very handsome airplane.

Owner comments
When I purchased my 1954 Cessna 170B in June 1987, I was looking for a taildragger that could carry my family, 100 pounds of baggage and fuel for 350 miles with reserves. The Stinson 108 and the Piper Tri-Pacer/Pacer meet the requirements about as we’ll as the Cessna 170B, and I fully expected to end up with a PA-22 and convert it to tailwheel configuration. My 170B just happened to become available locally, and even though it cost $3,000 more than a good Tri-Pacer, I am pleased with my choice.

The plane is a nice blend of classic looks and practical utility. It runs fine on auto fuel, burning eight GPH at a cruise speed of 115 MPH. At altitude, it will produce true airspeeds in the 135-MPH range.

Though my pre-purchase inspection showed three cylinders with compression in the 60/80 range, after putting 75 hours on the plane in three months, compression was 74/80 or better in all cylinders. The plane was in need of some TLC. It was out of rig and needed a wheel alignment. Working with my mechanic, I did most of the annual inspection myself. The only serious problems discovered were worn rudder cables, which were replaced, and a bent rod on the elevator trim actuator, which was straightened. The inspection revealed that the right wing is from a 1959 C-172, but the log has no comment as to why it was changed.

The 170B will land much shorter than it will take off. With two on board and full fuel, it is no problem to land and stop in 300 feet. Takeoff is not so impressive but noticeably better than a 172 with the same engine.

Visibility is very good for a taildragger. Taxiing can be done without S-turns, and the nose is very low in level flight. In fact, the low nose attitude in climb was my greatest problem in transitioning to the plane. Unlike most taildraggers, the runway ahead is in full view during climbout. This would fool me into raising the nose too much.

The only operational problem I have had is a stuck exhaust valve. After the second occurrence, the valve guides and stems were cleaned and I changed to Mobil AV1 synthetic oil. I had been running AeroShell 15W-50. A Continental engineer I spoke with was very high on AV1. He felt the extremely long oil change intervals Mobil has experimented with (500 hours, plus) were risky, due to lead build-up in the oil, but he cited very good experience with 100-hour oil changes in his Cessna 150 club airplane. A nice side benefit of the AV1 oil is the way minor leaks dry up, leaving the engine dry and oil-free.

The International Cessna 170 Assn. is an excellent club. It provides advice on maintenance, places to fly, etc. Members even pool their resources and get Cessna to make up a supply of parts, such as solid axles and seat rails.

I compared the specifications in the recent article on the Archer and Tobago (May 1, 1988 issue). They are really in a different class, but the lack of major performance differences is notable. With the exception of range, the 170B compares very we’ll with these new, higher-powered airplanes. Besides, the value of the 170B is going up at a very nice rate.

Gary B. Collins
Cincinnati, Ohio

 

I have owned a 1949 Cessna 170A for just under two years and have found it to be reliable, great fun and cheap to operate; there have been no surprises or unexpected expenses. Total time is 2,300 hours on the airframe and 860 on the engine. Last years annual, with me helping, cost $117.

Operated according to the EAAs autogas STC, the airplane burns 7.5 gallons of unleaded regular an hour. I have not had some of the problems that other owners seem to have encountered using autogas (soot in the exhaust, etc.). I do lean aggressively, though, and keep away from higher octane autogas to avoid the toluene additives. When I have to use 100LL avgas, I always add TCP.

The airplane is noisy, but addition of a voice-activated intercom solved that. It cruises around 115 to 120 MPH at 2,450 RPM.

Figure maintenance to be the same as a 172. Parts are still available, though some, such as some body parts, are no longer available. I had an entire front cowl remade locally for about $1,100.

As with buying any used airplane, a pre-purchase inspection could avoid later problems. Be especially wary for corrosion and cracked axles on some of the earlier aircraft. The International Cessna 170 Association is a great place to start if you are interested in buying one of these classics.

The airplane is just plain fun. It attracts attention wherever it goes. I use it mainly for grass-roots type fly-ins and for cross-country trips up to 500 miles. It doesn’t go fast, but its a fantastic way to rediscover the countryside; and at under $10 an hour for direct operating costs, you get to see lots of country.

Ron Adams
Germantown, Tenn.

 

My 170, a 1950 A model, has been in my family for the past 20 years. I feel the 170 is an excellent airplane that has extremely docile handling qualities, excellent load-carrying capabilities and reasonable speed at very reasonable operating costs. The airplane is a sought-after classic that keeps increasing in value.

I feel that Cessna took a giant step backwards when they phased out the 170 in favor of the 172. I normally cruise at 118 MPH, true, on 7.2 GPH. Even the 172 taildragger conversion cant match these numbers.

The airplane is great for flight training and as an all-around family airplane. The 170 is a logical move up for owners of smaller 140 Cessnas who don’t want to lay out the large investment required to purchase and operate a 180.

The 170 has an unusually good field of view for a taildragger. Visibility from the cockpit, both on the ground and in flight, is excellent (better than the 172). This is due, primarily, to the low-cut panel, down-sloped cowling and the close proximity of the front seats to the leading edge of the wing.

It also is an easy airplane to maintain, due to the absence of complex systems and its commonality with the 172. The O-300 Continental is an extremely dependable and very smooth-running engine and gives the 170 adequate power under most conditions. There are several STCs available to convert to 180 and higher horsepower, but I personally prefer the 145 Continental.

As Parts and Maintenance Coordinator for the International Cessna 170 Association, I find the majority of parts for the airplane still pretty easy to obtain. Cessna has been very helpful in supporting us when they were able to. The 170 association is one of the finest type-clubs, offering lower insurance rates, an inside track on maintenance and parts tips, and the comradeship of some of the friendliest and most helpful people I know.

All models of the 170 have excellent characteristics, but I feel the older ragwings and A models, in many cases, have been unfairly overshadowed by the later B models. A potential 170 owner who is shy on conventional gear time would be we’ll advised to seek several hours of dual from an experienced taildragger-qualified instructor to acquaint himself with the peculiarities of conventional-gear aircraft.

Although there are other four-place airplanes on the market that are faster or may carry more, I don’t feel any offer the all-around mission mix that is found in the 170. When this is combined with the airplanes classic good looks, I truly feel that it makes the Cessna 170 certainly one of the finest, if not the finest four-place airplane ever built.

Tom Hull
Hollywood, Md.

 

We’ve operated a 1954 C-170B in our business for general utility purposes and as a backup for a P210 photo ship since 1968. The aircraft was originally outfitted as a floatplane, with interior corrosion-proofing and lift rings installed above the fuselage, but it never actually has been on floats.

We converted the 170 over to a Lycoming O-360 with a constant-speed prop in 1981. It made the plane a terrific performer compared to the standard Continental 145-HP version. A couple years after the engine conversion, we relocated the battery to the rear fuselage, which markedly improved the balance of the plane, particularly on solo flights. We also installed a camera hole in the floor.

The aircraft has proven to be reliable, with no vicissitudes in either flight operations or maintenance. Cross-country, we plan on 105 knots at 55 percent power, with fuel consumption about 7.8 GPH.

The O-360 can rapidly deplete the planes modest 37-gallon fuel capacity at high power settings, so we tend to go high and throttle back, and hope for a tailwind. Another negative is the high noise level and drafty cabin. Our planes hands-off stability is poor.

In conclusion, the Lycoming power greatly increased the utility and productivity of the classic old 170 airframe. Its hard to imagine a better combination for the price.

Stephen J. Power
Vacaville, Calif.

 

I have owned a 1952 Cessna 170B since July 1978 and have found it a very inexpensive and virtually vice-free aircraft. I do my own maintenance and very seldom have to do more than routine servicing during annuals. I also did some modifications, including an Avcon 180-HP engine conversion 750 hours ago, and changed the interior using Airtex carpets and side walls. The kits were outstanding and fit with no reworking or modification.

There are two drawbacks, however. First, the 37-gallon fuel supply is not enough for the Lycoming conversion. I wish someone would make a retrofit kit that would add another 15 gallons. Second, the instrument panel becomes a mess when you have a couple of modern radios and a set of gyros.

The airplane will carry just about anything you can close the doors on and still get out short and fly high.

Tom Schad
Del Rio, Texas

 

I bought a Cessna 170B in 1964. Originally, three doctors owned the plane, but I am now the sole owner. All of us learned to fly in Cessna 120s, so this plane was absolutely no problem. A 1955 model, the plane now has almost 6,000 hours TT.

Like most Continental O-300s, my planes engine has been overhauled a few times. Quite a few hours have passed since the last one, but the jugs have been overhauled on an as-needed basis. As a result, I have two spare cylinders ready to go to save down-time.

Many years ago, the Goodyear brakes were replaced with Clevelands off a wrecked 172. This was probably the first significant update ever done on any old Cessna. The plane is flown at least once a week, unless I’m out of town or the weather is bad. In the past few years, I rarely have taken trips of more than a hundred miles each way. At one time, though, I had two kids in college in Santa Barbara and ran a weekly commuting service for myself and other parents of students who were neighbors and friends. There was minimal LAX hassle in those days.

It is difficult to establish the exact cost of maintenance, since the plane is a hobby and much of the maintenance is done when the mechanical or aesthetic problem is first noticed or the AD is first published.

Oliver R. Nees, Jr.
Long Beach, Calif.

 

I’ve owned a 1948 Cessna 170 since 1976. In general, the aircraft has been inexpensive to own.

The generator has been replaced twice, the voltage regulator once. I had to have a fuel tank repaired because water had collected and corroded the bottom of the tank. The rudder bellcrank broke when the plane was hit by heavy wind while parked four years ago; flap hinges also have been damaged by wind about every three years.

I’ve used autogas legally since 1983. The airplane burns eight GPH on short flights, 7.5 GPH on cross-countries. The Cessna 170 has no bad habits. Its easy to slip, three-point and wheel-land. It slow flies at 57 MPH at 1,950 RPM, cruises at 117 MPH at 2,450 RPM.

The 170 is a very forgiving aircraft, though the flaps are essentially useless (unlike the Fowler flaps on the C-170B). The heater also is useless (again, unlike the 170B), but it isn’t needed much in the bay area. The aircraft is easy to handle in crosswinds, though I did have one 45-degree crosswind at 30 knots where I had to use wing-walkers to park the aircraft.

In summary, the ragwing C-170 is an attractive aircraft. It is inexpensive to own and maintain, easy to fly, gentle in a stall and hard to spin.

Joseph J. Neff
Newark, Calif.

 

I owned a Cessna 170A (1951 model) for six years. In 700 hours of flying, I found performance to be adequate, even with four people aboard; cruise was about 100 knots on nine GPH.

The airplane had excellent in-flight handling qualities, but the small flaps on the A model left something to be desired. Ground handling was fair, with steering accomplished more by differential braking than with the tailwheel. I never did like the soft landing gear legs on the 170 and 170A, which would cause a teeter-totter effect when taxiing, especially in a crosswind. Later B models had stiffer gear legs, like those on the Cessna 180.

For a taildragger, over-the-nose visibility on the ground was excellent-much better than either the 120/140 or the 180. Because of inadequate heat and poor door sealing, cabin comfort was poor in New England winter weather. The back seat stayed close to OAT in flight.

My overall opinion of the airplane is favorable. However, for what some of these 170s are selling for, I would be more inclined to get a more recent vintage airplane and experience fewer nickel-and-dime breakdowns, as was the case with my 30-year-old airplane.

Robert S. Andrews
Claremont, Calif.

 

Also With This Article
Click here to view charts for Resale Values, Payload Compared and Prices Compared.
Click here to view the Cessna 170 features guide.