Budd Davisson, Plane and Pilot, 1999

Cessna's 185:
One Man's interpretation

Tom Rabourn decided to make this takeoff himself. We lined up on the centerline, with everything pushed forward. Flaps were at zero. Then the power went in and the big IO-520 up front started bellowing. The airplane quickly gathered energy and I glanced over; the airspeed was building through 35 knots. Then 40. Then, without warning, Tom reached down and forcibly yanked the flap lever almost all the way up. Faster than I could follow it with my eyes, the airplane literally leaped straight up, clearing the mythical 50 foot obstacle in a single bound. The airspeed needle stayed glued to 40 knots and we continued clawing upwards, nose in the sky, runway falling behind. Tom's re-invention of Cessna's venerable aerial pick-up truck, the 185 Skywagon really does it's number.

Rabourn, a recently retired airline pilot living in Carefree, Arizona just north of Phoenix, views his 185 as an after-college present to himself. "I had three kids in college at the same time and as soon as they got out, I bought the 185."

When he says, "...I bought the 185," however, it doesn't mean he actually bought a 185. What he bought was more of a 185 "kit" as it was far from being a complete airplane. In fact, all Rabourn got was the basic airframe missing the engine, interior and lots of parts. The airplane had been a research and development airplane for a well known turbine engine manufacturer who had stripped it out and replaced the original engine with one of their turbines, then abandoned it.

When Rabourn stood back and looked at the pile of parts, in his mind's eye he saw a different airplane than Cessna had originally designed. What he saw was the basis on which he could build the bush airplane he'd always wanted.

When Rabourn was finished building, actually resurrecting or reincarnating might be better terms, the C-185, he had received an unbelievable 26 STC's for changes made to the airplane. All of the changes had been made in the name of expanding on the airplane's already impressive utility envelope. The airplane had become an aerial version of a 4 x 4 super-truck which, although already impressively capable, was further modified to gully-run the desert and ignore topography.

Some of the mods are so small as to be invisible. For instance, Rabourn is a big, big guy. The in-seam on his jeans is 36 inches! So he wanted the seats to slide far enough aft to let him in and out without having to fold himself up like a pocket knife each time. The STC for the extended seat rails includes a short piece of seat belt, including the buckle, that clips to the front edge of the pilot's seat keeping it from doing the infamous Cessna Slide, racing back down the tracks on takeoff.

Other mods are more obvious, like the upward hinged, float plane doors which are also often fitted to jump planes and make loading outsized cargo easier.

The back seat area is more for carrying "stuff" than people. The seats (also STC'd) are cute little fold-away units that stow up against the fuselage sides creating a huge cargo bay, but pop into place when needed.

In the back of the cargo compartment is a survival kit weighing 143 pounds which is figured in as part of the airplane's empty weight because it is permanently installed. It goes where the airplane goes. Tom uses his airplane for bouncing around in the bush, and is prepared for any eventuality, but he also knows that out in the west, if you're outside the city limits and the engine quits, you're instantly in a survival situation.

Since short, ugly runways was where he was headed with the airplane, one of the STC'd mods was the P. Ponk Aviation STC, which replaces the gear mounts with a special unit that guarantees the gearbox will survive a ground loop or really hard landing.

Getting in short, means coming in slow, so Tom installed a Robinson conversion kit which not only puts a cuff on the leading edge of the wing, but couples the ailerons to the flaps so when the flaps go down, the ailerons droop with then, which steals some of their effectiveness. Tom flew the airplane for a while with just the Robinson kit, then installed vortex generators (VG's) along the top of the wing to put energy back into otherwise lazy airflow at slow speeds which made his ailerons more effective when the flaps are down.

The engine is the normal Continental IO-520D, rated at 300 hp for five minutes and 285 hp continuous. Tom, however, restricts his horsepower for increased engine longevity by keeping the rpm down on take off via what he calls an "Alaskan Prop Limiter"; that's a wooden clothes pin clipped on the prop control shaft that stops it at 2650 rpm, holding the power to 285 hp. I didn't ask if the clothes pin was STC'd.

What makes the airplane really work for him in Arizona and the high density altitudes of the west, however, is the addition of the Air Research turbocharger by Turbo Tech. A manual waste gate control turbo, it allows him to hold 75% power to 17,000 feet which also lets him flight plan 150 knots at 10,000 feet while only burning 15.5 gallons per hour. That's at 27 inches of manifold pressure. Aren't turbos wonderful?

Incidentally, the airplane was so completely taken apart that the FAA registration has it listed as a 1990 Skywagon, not a 1967.

The 185 was originally born as Cessna's answer to those folks in the 1960's who were saying, "Hey, we love our 180's, but can't you make them a little larger? Make them carry more." So Cessna took what had been a winning design and made just a little more of it. In 1961, when they introduced the 185 Skywagon, it literally was just a 180 on steroids. The empty weights stayed about the same, 1525 pounds, but the gross went up from 2,800 pounds to 3,300 pounds. Bingo, just like that, they had another 500 pounds useful load to play with. To help get that extra weight off the ground, the 230 hp 0-470 Continental of the C-180 was hopped up a little, turned a little faster and given a rating of 260 hp in the 185. In 1966, answering the same folks who were probably saying "Okay, so now the airframe will carry the weight, now give us the power to get it off the ground better." The answer was the 185E which boasted the IO-520D rated at 300 hp.
With that kind of power and displacement increase, the airplane now was capable of carrying what ever you could put into it. In fact, even though the empty weight of the bare airplanes went up, the advertised useful load was 1840 pounds which included 65 gallons (84 gallons optional) of fuel. The airplane was only five knots faster than the C-180 and stalled four knots higher, but it was also carrying nearly 600 pounds more cargo/people/fuel. None of these performance figures, of course, mean anything when put against Rabourn's modified airplane.

As we climbed into the airplane, it was obvious to me that everything about the Skywagon makes it feel like a much bigger airplane. One thing that immediately made it seem so much longer, even though it really isn't, was how far I had to pull the seat forward to reach the rudder pedals. In fact, between the upward hinged door and the extended seat rails, it has to be the easiest Cessna on Earth to get into. These would be good mods for any Cessna.

Tom orchestrated the start (it was hot and we didn't need me screwing it up) and we were on our way. The heavy weight aspect of the airplane was obvious from the very beginning. The amount of power it took to get it moving and the amount of rudder it required to make a turn all hinted at inertia. It didn't want to be moved and then, when it moved, it didn't want to be stopped. This is all relative, however, as after a few minutes the feeling of inertia disappeared to be replaced by a feeling of solidity.

After a short conversation on the taxiway about how I could almost see over the nose, Tom suggested we crank my seat up. Crank, crank, crank. Now I could absolutely see over the nose.

Out on the runway, I purposely hunched down a little so the nose would hide the very center of the runway which gave me a hard reference where the edge of the runway intersected the cowling. Power going in, I simply hugged the yoke to my chest and stared at my reference until the tail felt like it wanted to come up, then I eased it forward (against some trim, which I should have set a little further forward). As soon as the tail came up I had C-182 visibility. I've never been crazy about spring gear and I could feel the main gear legs sort of wobbling around. The airplane wasn't doing anything, as it was taking only a tap here and there to keep it straight, but that soft feeling made it difficult to know exactly what it was doing. On the next takeoff, I raised the tail a tad higher and pinned it on more securely which loaded the legs and eliminated some of the wobblies.

Once off the ground, Tom immediately set the turbo control for max continuous power and we wandered up hill at 900 fpm while holding 70 knots. It was about 90° out and we were at 2,500 MSL, so the DA was about 5,000 ft.

In the air, the airplane actually feels big. I hadn't expected it to feel much different than a C-182, but it does. Its wing loading is a solid 2 pounds per square foot heavier and you can tell it. There wasn't much turbulence, but what little there was, the airplane just chopped through. In playing with the controls, the ailerons were heavier than a 182's and the airplane's response was a little slower, all part of the big airplane feel.

Once at altitude I immediately began playing with the stalls and slow flight. The first stall was clean and the yoke was against my chest at something like 52 knots IAS. I held the yoke back, just to see what it would do, which was exactly nothing. The stall didn't break and the airplane just mushed ahead. I added some speed, grabbed the man-sized handle on the floor between the seats and yanked it up to give me full (40°) flaps and tried the stall again. Same thing, except the stall was down around 38-40 knots. The Robinson kit must really work, because in the same situation, the book says a stock Skywagon would be stalling around 54 knots.

Then, with the yoke still against my chest and flaps down, I slowly eased power in, bleeding off back pressure as the nose tried to come up. I found I could motor around with something like 13-15" and 35 knots all day long. The ailerons were a little soft, but the airplane was totally controllable and pulling back to simulate an inadvertent stall in that situation only generated a slight bump and a little roll to the left. Leaving everything alone and relaxing a hint of back pressure put the airplane back flying again at 35 knots.

On downwind, I got out 10° of flap which made the airplane very manageable and speed-stable. I bled the speed down to the 65 knots Tom recommended, keeping a little power in to maintain glideslope and to fly out around a noise sensitive area. I opted to fly final with only 30° flap, rather than hanging them all out. All the way down, the end of the gravel runway just sat in the windshield, until it started moving towards us and I bled the power off to let it down.

The first landing wasn't pretty as I was still trying to figure out where the ground was and planted it on a little too firmly. We got a little bounce and I just held the attitude waiting for it to come down. Gravity always sorts these kinds of situations out and it settled back on to roll pretty much straight ahead even though we had a slight crosswind. On the next landing, I was able to ease it into ground effect with a little more grace and we touched down with no bounce. Tom had warned me to make sure the trim was full aft prior to touch down or it would do the famous main gear to tailwheel and back hippity hop 180/185s are famous for. I didn't see a sign of that tendency.

On roll-out I could feel the airplane try to initiate a slight turn, but then I'd feel the gear legs twist sideways, greatly softening that turn, giving me all day to keep the nose straight. That's one of the strong points of the spring gear, designed and patented by old time race pilot, Steve Wittman. At no time on rollout were my feet doing anything more than just tapping now and then. It was really easy to control, although being on the gravel probably helped that. We didn't make any hard surface landings so I don't know if it has the same manners there or not. I doubt if it does.

Tom gave me several interesting demonstrations of the airplane's unique capabilities including the jump takeoff, which works with the Robinson kit to drop the takeoff run from 725 feet for a stock C-185 to 487 feet for the Rabourn Special (I just made that up). One of the real eye openers, however, which showed what a smart aerodynamycist can do for an airplane was a full-flap, full-deflection slip to a landing. Cessna doesn't recommend that maneuver with their stock airplanes because the elevator is partially blanked and the airplane bobs around in a manner that can get your attention. With the VG's and Robertson STOL kit, however, the Tom's Skywagon was a pussy cat in the slip. It was super stable and would let you put it right where you wanted it.

Rabourn has obviously put a huge amount of thought and effort into his airplane. And now, that it's finished what's he going to do with it? "Well, there's this little spot on top a mesa, I saw a while back I'd like to go explore, and then there's...."

Explore, that's what he's going to do with his airplane. He's going to poke into nooks and crannies of the west that haven't been poked before. BD