The low wing Cessna 170 – a great idea that didn’t fly

The three views, of the airplane described by the article title, that accompany this piece were taken from an “unofficial” board size drawing I knew I had stowed away somewhere around the house, but only recently found and reclaimed. The drawing is entitled “Preliminary Design, Model 170 Replacement” and dated February 2, 1955. It is initialed as drawn by “B.W.” That it doesn’t have a drawing number, nor an assigned project number for the model illustrated says it was not a formally established undertaking of the Cessna Flight Test, Aerodynamics and Preliminary Design group of which I was a member back in early 1955. It was just a pictorial of a great idea I had – and since I hadn’t looked at it for about 50 years it was a revelation for even me. I wasn’t real sure of what I would see.

Low wing Cessna 170 drawing
The tail looks familiar, but the rest looks very un-Cessna.

In early 1955 we had what I thought were three exceptional and certain to be widely accepted low wing Cessna designs in work: the twin, prop driven Model 310, already being sold, the twin jet T-37 Air Force trainer with prototypes being tested for qualification, and the four engine prop driven Model 620, which – while still in development – in my view was going to be big. Big for a Cessna airplane and a big seller in its business aviation arena.

Sure we had a couple of great single engine airplanes, the Models 170 and 180, but they were of the comfortable looking, familiar but staid old high-wing configurations. What we needed, I thought, was a complete line of sporty looking low-wing designs, requiring a redesign of the 170 and 180 to fit in the sequence from commercial single-engine four-place airplanes through the recip and jet twins, the 310 (commercial) and T-37 (military), and finally to the four engine 620 business aviation entry. (Depressing note: The 620 was canceled two years later just as it was being certificated. The other two became the icons I anticipated.)

Thus I worked with a preliminary engineering board designer, both of us located in the engineering area in the aft part of Cessna’s experimental hangar, to create a vision of the concept of good looking low-wing versions of the 170 and 180 – not concrete designs but something to generate interest in the idea with the company management.

That board designer, B.W., was Bill Wise, later to be VP of Engineering for competitor Beechcraft. My memory says we did a similar design, as that presented here, for the 180 as well and why I decided to save only the 170 replacement drawing is a mystery – maybe they looked too much alike. My memory also says I did only fundamental stability and control and performance analyses on each just to make sure we were presenting reasonably practical examples. It was that new concept for Cessna – that is, let’s be totally more sporty – but not specific configurations, that I wanted considered.

Cessna 170 low wing from above
From here it looks like any other Cessna.

At the date of the drawing we were working on the next 170 model, the 170C, which would have been a tail wheel airplane with a squared off empennage – and were not considering a tricycle gear version of the 170 at all. But competitors were offering tri-gear, four-place models – most specifically the high-wing Tri-Pacer – and sales of the 170, the B model, were tapering off. So a decision was made to expedite a tri-gear 170, the 172, with the squared off tail we had designed for the 170C. That expedited project used a lot of our resources – the 172 was offered for delivery in 1956 – and I don’t know if my low-wing concept was lost in the shuffle, or was just not considered as fungible as the quickly available 172.

Note that I never got an actual turn down on the “170 Replacement,” just never heard anything. Later that year I moved West to the Military (T-37) Division and was as surprised as anybody with the great reception that grew for the 172, which of course was a product of the Commercial Division back on the other side of town. Readers will know that it became the most produced airplane in the history of aviation. Maybe going for the 172 was a great management decision.

Readers may also be disappointed in the low-wing 170 design presented here. It’s not a major departure in design, so maybe is, and might have been, seen as just a “vanilla” offering. Additionally the drawings leave out a lot of detail that would be interesting to aircraft devotees. Most importantly, the cabin area is shown as a fighter like canopy arrangement, and no method of entry is depicted – could have been a sliding or rotating canopy, or even doors that encompassed that part of the canopy. Off to the side on the original drawing, and not reproduced here, is a pencil sketch of what looks like a step, such as for passengers to get between wing and ground. It may have been the result of a post-drawing discussion. Other things likely on the views with this article are my recent notations for getting the trimmed down versions from the original – and not poor lettering on Bill’s part.

The design is a tricycle geared one, so all of our models would then be, but the drawing doesn’t show whether it is fixed or retractable – the initial idea was fixed gear, as the 170 and 180 were. (And the subsequent 172 and 182 were, as well.)

Low wing Cessna 170 from front
It almost looks like a Cherokee from the front.

The propeller is only outlined, but we would have selected a fixed pitch for the 170 version, and a constant speed propeller for the 180 version. The drawing shows a symmetrical wing airfoil, but that only indicates I hadn’t selected one of our standard airfoil sections yet. This design has the “square” tail of the 170C, and its derivative 172.

The low-wing design(s) doesn’t have the “draggy” struts of our high wing models, and I may have gone overboard on assuring good overall performance by using a higher aspect ratio wing than on the 170 and 180. The new design was intended to fit in a standard T-hangar too, and the additional span might have made it somewhat harder to maneuver getting the plane in and out.

We of course had in the back of our minds the familiar low-wing versus high wing trade-offs, but a consistent, low-wing, high performance appearance in our series was being intentionally, if silently, proposed as the dominant consideration.

Cessna 170B
The tailwheel, high-wing Cessna 170 was a fine airplane, but did it lack some modern styling?

So we showed a low-wing, fixed tri-gear configuration. It was at least five years later that a similar configuration, the Piper Cherokee, was offered by a competitor. But what familiar low wing airplanes were our competitors offering, or which were being flown, in the meantime? In the two place category there was the tail wheel, retractable gear Globe Swift, or the fixed tri-gear (unspinnable) Ercoupe. The nominal four passenger Beech Bonanza was tri-gear, and retractable, and so was the North American/Ryan Navion – and it had a sliding canopy. That’s OK for the “Poor Man’s P-51.” Might have to go back to the Spartan Executive to find a four-place low-wing airplane with a retractable gear in a tail wheel configuration.

And it was almost ten years before Beech offered the four place, fixed, tri-gear Musketeer, and it took Cessna more than a generation to provide, actually someone else’s, low wing, fixed-gear 170 like airplane, the 350 Corvalis. Of course it had other more modern aspects than our 1955 170 replacement had.

So Cessna, and others, later mimicked that low wing 170 replacement approach. That makes me even more happy to now be able to show you the conceptual three view of our/my 1955 low wing 170 design. And I still think the idea of a complete line of fast looking low wing Cessna airplanes was a good one. The timing just wasn’t right.

10 Comments

  • Sorry, I think you made a mistake then. The high wing has more going for it; shade in the summer, rain protection in the winter, no fuel pumps, easier entry, more hangar space (you can walk under it), and it’s lighter. The only good thing about a low wing is that it’s easier to put gas in. Cessna management called it right that time and the Piper vs Cessna sales proved it.

    Today, the low wing is king. Cirrus and Van’s Aircraft are kicking the competitors around. I guess the market has changed; modern customers just like that long hike around the wing in the hangar.

    • Steve:

      I think it’s largely cultural. Just about all airliners (what the general public considers to be “real airplanes”) have low wings. In little birds, trepidatious passengers overwhelmingly prefer to be “sitting on top of the wing” rather than be “hanging under the wing.” Most pilots don’t really care, although I admit that I’d rather fuel a low-winger than get up on a ladder or strut-step. (Single-point fueling is even better!)

      It’s hard to argue with Cessna’s success with their ubiquitous high-wing singles. The relative success of their 310 versus their 336/337 are an interesting case, though. Could there be a bias among pilots, that causes them to prefer low-wing designs? Is it that a low-wing twin is more like one of those “real airplane” airliners?

      As Bob Hoover would attest, the Commander twins always were fine airplanes. But they were outsold by far by their low-wing brethren. I’m sure that Harry could offer some insight regarding why the 310 and 620 were low-wing designs. Both were “clean sheet” designs, as I recall. I loved Harry’s use of the word “sporty!”

      -Yars

      • Oh, I wouldn’t say it’s cultural. When you get into high speeds, then the strut braced high wing doesn’t work so well and it’s much easier and lighter to mount a cantilever wing underneath. If those airline passengers didn’t have jetways to keep the sun and rain off and had to crawl over the wing to get in, they wouldn’t like it so much either. And if the maintenance crews had to walk around a 100 ft wing in the hangar, they wouldn’t be too enthused.

        But, for a Bonanza type fast airplane, I would agree with Harry. However, if you are just replacing a 170 with a similar speed airplane…Well, Piper did that. The 172 beat them badly as well as beating out the Cessna replacement; the Cardinal.

        • Stephen,

          It is highly likely that Cessna’s high wing 172 beat out Piper’s low wing Cherokees in sales rather more due to their more effective marketing than due to any perceived advantages of high wing vs. low wing.

          I learned to fly in the mid-1970s, and that was at one of the ubiquitous “Cessna Pilot Centers” that had their mass-produced, Cessna-centered pilot training curricula, books, logos, and of course gazillions of Cessna 150/152 trainers. There was no equivalent “Piper Pilot Center” marketing model. As a result, Cessna virtually owned the training market during the peak GA expansion years of the 1970s , and naturally Cessna used that advantage to hawk their 172s as the logical first step up from the tiny 150/152.

          The difference in sales of Cessna vs. Piper also isn’t quite as much as you seem to suggest – about 43,000 C-172s sold vs. just under 33,000 Cherokees sold, and the 172 had a four year head start on the Cherokees, during which time the 172 sold about 4,000 units.

          As soon as I earned my PP certificate at the Cessna Pilot Center, the very first thing I did was go over to another FBO and signed up for a checkout in their Piper Archer, which I preferred much more than the relatively low power C172. I own a Cherokee 180 now.

          I always preferred the low wing birds over high wingers. I rather suspect that at least part of the reason for the big success of the wide variety of low wing birds over the decades (including the Piper Commanches, Cherokees and all the variants, Bonanzas, and Mooney’s, as well as the popular Cessna twins) is that they “look like real airplanes, and not like big bugs”. Being able to see the end of the runway in the pattern during the turn downwind to base, and base to final, is also quite nice, and of course not needing a ladder to refuel is great. Fuel pumps in low wingers are not an issue – they work great and there is redundancy with both mechanical and electrical pumps.

    • Although I like both high and low wing aircraft for different reasons, I lean toward low wings simply because they give me a view of the runway at all times while in the pattern. They also float less in ground effect during landing on hot days.

  • I’m going to step in here now even though I think this article will cause many controversial viewpoints that I’ll have to address.
    There are two things in the article that support Steve’s position. The success of the 172, and that sporty looking photo of the 170 – wheel pants make the difference. But in opposition, what’s the general aviation model with the longest production run in history? Beech’s low wing Bonanza, starting right after WWII and lasting decades.
    My “theory” in 1955 was that the industry was entering a new era, leaving the time of planes for people who were going to be pilots anyway, and enlarging the field with planes for consumers that wanted them for transportation – maybe personal, maybe business, maybe both, but wanting them to be easy – and safe – to fly. Related, I had already concluded that color schemes and matching interiors were more attractive than the modest aerodynamic improvements I spent most of my time on. I felt that low wing design would be attractive to this market. As the article says, we were aware of those still prevailing low wing versus high wing arguments, which are mostly a matter of personal preference.
    Answering Yars, I was not in on the beginning (preliminary design phase) of the 310, but I think it was influenced by the popularity of that same fast (and sporty) Beech Bonanza. The 620 started with a market survey of business aviation participants and I don’t remember if low vs high wing was a factor. We liked low wing to be like the airliners business people used, but were concerned because the users wanted to be able to fly into smaller general aviation airports and the wingspan was going to extend beyond the runway width for some of them – so taxi slowly and shut off the outboard engines. Also refueling a large airplane like the 620 might have been difficult at some GA airfields if the design was high wing – and filling it up might require all the fuel capacity the operator had in any case.
    And, although I favored, with the 170 replacement, a line of low wing designs I also recommended keeping one of our high wing lines in production for those pilots that wanted that – especially bush pilots.

  • Sorry Harry, but I’m of the opinion, (mine alone,) the high wing design beats the wings off the low wing design. But, I never was the “sporty” type when it comes to aviation. Never felt as if I was just a wannabe fighter jock stuck in the mud in civilian life. Love the Cessna 150/152/172 type, especially as they are perfect for the “sight seeing” type flying I love, (especially when I can even open a window and point my camera out there and get perfect pictures. (Besides, your drawing makes me think it’s a Navion imitation, no disrespect intended, especially as you guys have way more qualifications than I.) Thank you for your article. I enjoyed reading it.

  • Doyle – Based on what you say you do while flying you seem to be the type that was going to be a pilot anyway. My goal was to attract “new” customers who wanted an airplane almost solely for their transportation needs. However,if you stack up fixed gear airplanes of the period, by the three biggies, Cessna, Piper and Beech, total sales of low wing airplanes (Cherokee, Musketeer)just barely exceed that of the high wing ones (172,Tri-Pacer) That’s according to Wikipedia, and I’d almost call it a tie. But if you compare retractable gear types (Bonanza, Navion, and Commanche) these low wing jobs outsold the lone high wing, the 210, by well over a factor of two. I throw in the Ryan airplane, even though we really didn’t try to copy it! And the whole plan for the low wing tri-gear 170, and 180, was to extend them to retractable gear models. As stated above, the plan, according to me, was also to maintain at least one high wing airplane – probably the 180- in production. Of course there can be other comparisons, like bringing in the 182 – but I think that if you look at my total plan the low wing series would have been very marketable in the long run. But how can I fault management for going for the quickly available 172 as the existing market demanded?
    Harry

  • When I was doing preliminary design similar in nature to Harry at Gulfstream American back in the early 80’s, we wanted to design something that replaced the old Commander twins. Marketing said, it had to be low wing, which from a structural standpoint was better anyhow. We were able to have the carry-through spar below the cabin floor and offer a standup isle for the passengers without having to worry about the head room if we had the wing high. Of course Piper beat us in announcing their Cheyenne 4, which caused Mr. Paulson at the time to cancel our efforts and re-direct us toward the Peregrine Light Jet, which we converted from the Hustler 500 he brought with him from American Jet.

    Rich

  • I find Rich’s information about Gulfstream American very interesting because in the early 80’s I was still in an employment period with the Federal government and not following the aviation industry very well.
    But I’m going to go in the other time direction, because it reminds me of something in the very early part of my career with Cessna in the 1950’s – the fanjet 310. It was so early in my career that I wasn’t choosing my own projects, so it was somebody else’s idea. The 310 had not yet flown, but the wind tunnel tests had been completed and I did some of the analysis of it. What is interesting is that some of my colleagues of the time later had no memory of this assignment, and some even said it never happened. But my memory was substantiated when I found a memo about it in the archives of our local Wichita State University – and the memo does not have a sender’s name but has the initials of the person in charge of preliminary design at Cessna at the time. There is not much of a climax to this story because the memo is to engineering management but not very specific and certainly non-committal. The subject never came up again and I later got smarter and realized it was not something that was ever going to happen at Cessna, at least in the future as I saw it then. Of course I didn’t know that I would soon be working on twin jet trainer and a four engine business airplane.
    Anyway the idea was to use as much as possible of the M310 design and structure, and I had to make up an engine because there weren’t any of the necessary small size in existence at that time. I did venture some and did both straight wing and swept wing versions of the idea – the latter with 15 degrees of sweep so mostly for show, not performance. Although I wasn’t asked I agreed with the sense of the memo that there was not much to recommend the idea. The P.S. to this tale is that I also did a turboprop version of the 310 at that time, and again had to make up the engines (we called them rubberized) and I think that did happen after I had left the company. It was more likely.

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