Text and Photography by Budd Davisson, Air Progress, November, 1973


Sometimes You get to do something really cool, and flying

the Evangel 4500 in South America was one of the best

 

As we turned final, my heart nearly stopped because it was wedged solidly against the back of my teeth. We had the gear down and were pointed at this ridiculously tiny box canyon. It wasn't actually a canyon, but it might as well have been because it was just a slit in the jungle and the trees on three sides were 60 feet high. What was scaring the devil out of me was that the whole "canyon" was a little over 900 feet long, and we weren't exactly flying a Super Cub. The sweat running down my legs was starting to pool in my boots as I looked back between the seats at all the junk packed behind us: a 55-gallon drum of gas, three people, assorted jungle goodies and goodness knows what else. I figured the pilot, Ron Macintosh, knew what he was doing, but twin-engine airplanes just don't land on air-strips like this one---not more than once anyway.

We crept over the first row of trees and Ron slowly brought the throttles back and started to flare. I didn't notice what he was doing because I couldn't take my eyes off the trees at the other end of the runway. I thought about my wife and child. I thought about the five bucks I owed a friend. The trees were staring down on us as the tires thumped onto the runway, and I instinctively slid my feet up on the rudder pedals to help Ron smash the brakes to the floor. Then a crazy miraculous thing happened we stopped moving. Just like that. The brakes helped a little, but even so, we hadn't used more than two-thirds of what they laughingly called a runway. Then I heard a loud rush of air and I realized I'd been holding my breath ever since: we turned base. Was I scared? I'd prefer to say pensive, but I'll have to admit that I saw the Evangel 4500 do things that no twin-engine airplane has a right to do.

The Evangel has had its share of press coverage since its debut in 1969, and it's been the brunt of many jokes: "looks like it's still in its shipping crate," or "has the grace and lines of a tool box." And every one of these remarks is true, even though most of them were probably made by someone gazing at the Evangel's outright cubism through a coffee shop window at some Stateside airport. When test flying a STOL airplane from a 3,000-foot runway, it makes little difference that it uses only 500 feet because you still have lots of room left. Under those circumstances, it's easy to seize upon the obvious and be terribly witty. And the Evangel definitely inspires the comic in all of us. But somehow, when I was standing 200 miles out in the jungle, swatting gnats that mistook me for a banana, and measuring off runways that were as short as 450 feet, those fantastically funny metaphors were neither funny nor appropriate. The Evangel will not send devotees of sleek and beautiful aircraft into a frenzy, but, when it comes to doing the STOL thing, it is one fantastic piece of hardware.

When I first saw the airplane at the Bogotá, Colombia airport, it was easy to see why it had given rise to so many snickers. It's so square it would have looked just right with gallon paint cans for spinners. It may not be beautiful, but it's everything its designer, Carl Mortensen, wanted it to be. Mortensen had spent enough years trying to coax clapped-out Stinsons and Cessnas up out of the jungle to know 'there had to be a better way. Where he and his fellow missionary pilots were flying, if an engine even coughed you stood a good chance of becoming dinner for something wet and slimy. He knew what he wanted, but it wasn't to be had. He needed an airplane that would not only carry a load, but could operate out of some of the world's smallest runways and still offer the safety of a second engine. Above all, it had to be functional. Since he couldn't find what he wanted, he returned to Orange City, Iowa, borrowed a slide rule and got into the airplane building business.

The South American interpretation of "functional" is that an airplane has to be able to pogo-stick its way in and out of tiny airstrips, but the average Tijuana teenager has to be able to fly and maintain it. The Stateside definition of STOL includes slats, slots, flaperons, fences, cuffs and all sorts of fancy add-on stuff that can go wrong. Not so the Evangel. It gets its leapfrog STOL characteristics from a fat wing and two 300-hp Lycomings-nothing complicated to foul up. As far as maintenance goes, the airframe is so incredibly simple, most parts can be made by bending flat sheet over a table edge. When I looked closely, I noticed lots of little patches on the outside of the skin that were actually doublers and clips. All airplanes have these, but most hide them inside, so they don't show. Nailing there on the outside means the structure doesn't have to be joggled or set back to make room for them, which also simplifies field repair.

The main gear legs are identical and can be swapped left for right. They are welded up out of heavy wall steel tubing and look beefy enough to support an airplane twice the Evangel's weight. The full-swivel tailwheel just sits back there, centered by bungees, keeping the tail up out of the dirt.

The outer wing panels have to make up for the center section's lack of dihedral, so they are angled sharply upward, ending in bat-like booster tips. With all the bending and curving, the wings make the airplane look like Orange City's answer to the pterodactyl.

I discovered my only consistent gripe about the airplane immediately upon trying to get into it. There is no step, so you have to open the door (there is one on either side of the cabin), then hoist your posterior up on the wing using the fuselage and nacelle as parallel bars. Then you take a feet-first leap into the cockpit from your perch on the wing. These gymnastics got to be a real drag after a while, though.

Several things made the trip from Bogotá to the missionaries' base camp at Lomalinda interesting. I knew this wasn't the place for me to be flying when Ron fired up the engines and then started stuffing a steady stream of Spanish into the boom mike. No habla Espanol. Another thing that had me mildly worried was that the altimeter read more than 8,000 feet while we were still on the ground; I'd read in the manual that the Evangel's single-engine ceiling was only 6,200 feet. I asked Ron what would happen if we lost an engine. He replied the obvious: We'd land shortly thereafter-another reason I didn't really want to be a bush pilot.

Ron has an interesting way of working around the Evangel's low single-engine ceiling. That was good because the mountains between us and Lomalinda were over 10,000 feet MSL and covered with clouds. The rest of the world knows them as the Andes. He climbs out over Bogotá to 15,000 feet before he heads over the mountains. He calls this his "drift-down" altitude because he's found he can drift down to airports on either side of the mountains from that altitude. As we were poking holes in the clouds, we occasionally broke out between build-ups and I'd see the not-so-friendly mountains below us and I hoped his drift-down theories would work. (Evangel is now certifying a turbocharger installation that should reduce the pucker factor of this type of flying considerably.)

I have to admit to being a tad let down at seeing Lomalinda because it was so civilized. I had been leafing through old copies of National Geographic and had visions of thatched huts, head hunters and pythons. Lomalinda looked like my hometown in Nebraska transplanted into the middle of the world's largest golf course. "Lomalinda" means "beautiful hill," and it is so named because the surrounding area is a lush grass plain dotted with uniform little rounded hills. I was afraid I wouldn't see the Evangel do its STOL thing.

Lomalinda is a thriving little missionary city in the flatlands 150 miles south-east of Bogota-55 scary minutes by air, and nine grueling hours by car. Its 1,400-foot dirt-and-sand strip looks pretty short when you first see it, but it's a regular JFK for the Evangel. Lomalinda is the central base camp for the Colombian branch of the SIT, the Summer Institute of Linguistics, a scientifically oriented subsidiary of Wycliff Bible Translators, and the operators of Evangel 02 Lima. The SIL uses the airplane to fly their two-man (or woman) teams of experts in and out of the jungles where they live part time with the tribes. They study and record the native languages so they can translate various educational and agricultural books for the Indians.

Ron Macintosh's little jungle airline operates the Evangel and a couple of Helio Couriers on a loose schedule. They try to make supply runs to the dozen or so SIL teams in the bush once a week, although they may end up bouncing across the jungle anytime in response to a radio plea for supplies or medical assistance.

Since the Evangel is the key to the SIL operation and the means of survival for many, it is maintained like Air Force One. Of course, an open-sided shed with dust blowing through is a long way from a climate-controlled hangar, but to the Evangel it's just as good. When Mortensen designed his airplane, he knew that maintenance would have to be simple enough to be done with pliers and some bailing wire, so everything is easy to get at and easy to fix. The 300-hp Lycomings are housed in foot lockers cantilevered off each wing and are easy to get to. We came in once with the symptoms of a clogged injector and the mechanics had the engine stripped, injector cleaned and the cowl back on before you could say, "Where's the lineboy?"

After loading a 55-gallon drum of gas and buttoning up the cowlings, Ron told us to saddle up. The seating accommodations in the rear are eight cushions that you position against the wall and belt yourself into. The front seat was at least as uncomfortable as a clothes hamper, but I understand current models are better.

The cockpit is as homey as a Patton tank. There isn't a single compromise to aesthetics. No curves, no ABS plastic panel cover, no vinyl seat covers. Although later models have been spruced up a little, 02 Lima's cockpit was so Spartan it was comical. The throttles, mixture and prop controls were levers sticking out of a square box-they didn't even have knobs on the ends. It looked like a herd of butter knives stuck in a loaf of aluminum bread. The flaps and gear were operated by a hand pump (replaced by an electric/hydraulic unit in later models) between the seats with a selector valve that chose either flaps or gear. And of course, in true bush-pilot fashion, it uses a he-man stick rather than a control wheel.

Takeoff was not unusual and I didn't give a thought to where we were going. I had no feeling of being over jungle until we were well on our way to cache our gas barrel at the strip at Utoya. I looked down at a dirt road under us and commented to Ron that if worse came to worse, we could land on a dirt road. He smiled slightly and told me that would be the last road we would see for almost 150 miles. He also said all the water was full of piranhas.

As far as the eye could see, a level green layer of trees stretched out, broken only occasionally by a river. In the distance we could clearly see some flat-top hills, and a quick measurement with the plotter showed them to be an incredible 95 miles away. Out there, over the region called the Vaupes, you don't hop from omni to omni. The Evangel had one omni, two ADFs and a high-frequency transceiver, and the VOR didn't look as if it was used much. The compass and ADFs were the primary navigation aids. This was the first time I had ever flown with an HF radio and it is the most incredible form of communication I have ever seen. When we left Bogotá the day before, Ron had contacted the relay station at Lomalinda right over the mountains to tell them we were ready to take off. While we were out over the jungle, he kept a constant narrative going with the radio. He would report his position over such and such-a rock formation that was usually so small I could hardly see it-and his ETA over the next known checkpoint. He even reported when he started his takeoff runs so if he stuffed it in they would know immediately. The SIL had established their own form of flight-following so the base knew where the Evangel was at all times.

The 900-foot strip at Utoya was where I first saw the Evangel perform as a bush plane. In addition to Ron and me, we had nearly full tanks, three people, a full 55-gallon drum of gas and so much other junk I couldn't see over it back down the cabin. We were close to gross weight. Ron started letting down and pumped his gear and flaps out. Then before he set up a pattern to this slit in the jungle, he slowed to near stall speed and felt for the stall buffet. This way he knew exactly what his stall speed was for this weight. He fixed that number in his mind and made his approach accordingly. I followed him through because I knew somewhere along the line, I would have to do this same thing.

Utoya was definitely a one-way strip. One end had 60-foot trees while the other had little 20-foot ones, so you had to land into the big ones and take off away from them. This time we were lucky because there wasn't any wind at all, which is at least better than a tail-wind. We came down the chute at a little over 70 mph IAS and touched down in the first 100 feet. Even though we were skating down into a tremendous dip, normal braking got us stopped in not much more than 500 feet.

When the props ticked to a stop after turning around at the end of the run-way, I was startled to see small brown bodies coming out of the bush on either side of us. Some were wearing cast-off dresses or trousers while others sported the traditional breech cloth. To them, the Evangel was the Flying Canoe, and the rolling runway hacked out of the jungle was its resting place. They showed no fear of it, but rather accepted it as we accept Apollo rockets: something that's perfectly normal, but doesn't touch them directly.

After I had fallen out of the cockpit, one of our passengers lunged at me with a can of insecticide. She explained that the bugs would drive me crazy if she didn't spray me well. I didn't object. I noticed the natives used some sort of mud or charcoal mixture for the same purpose.

Utoya is home to Dave and Jan Whistler, the local SIL translating team, who share the jungle around the airstrip with a couple of dozen native families. Whistler got some of them to help wrestle the 55-gallon barrel out of the cabin so we could refuel on the way back. The four-foot double cargo doors of the Evangel came in handy then. They're so big and so well located you could easily load a box the same size as the door and nearly half as long as the fuselage.

I spent the next several days being impressed by the Evangel. We went into runways as short as 750 feet with loads varying from half to full, and not once did the Evangel need much more than half the available runway for landing. The takeoffs were interesting because VMC. wasn't really taken into consideration. The handbook, which is one of the most thorough ever compiled on an airplane, lists takeoff distances at various weights and liftoffs of 65, 70 and 75 mph. It also gives correction factors for soft runways and tailwinds. Ron referred to the book religiously, computing his density altitude often, and we almost never used more than 400 to 500 feet to get off. He'd lift off and then fly right on the deck until he had VMC which took 1,200 feet. Then we'd pull up and climb out at more than 1,000 fpm.

Little by little, I got to try my hand at being a bush pilot and I found the Evangel made it almost easy. On takeoff, the problem wasn't getting it off, it was keeping it on. On my first takeoff with only a 'partial load, I didn't get the tail high enough and we lifted off at 55 mph and climbed out with no sweat. Later, I tried to hold it on to get up to the 80 mph VMC, but I just couldn't do it. At around 70 to 75 mph, no matter what you do, or how you're loaded, the rough runways bounce you into the air.

Initially, you have to depend on brakes for directional control, but the huge tail gets effective pronto. The best rate-of-climb speed is 95 mph, which really pokes the nose up in the dive. We almost never climbed at less than 1,000 fpm, regardless of load, and the temperature was close to 100 degrees most of the time.

During landing, I came to really appreciate having a stick control, rather than the conventional wheel. The kind of runways and approaches, as well as the general feeling of the airplane, made you feel as if you should be flying a Super Cub, and the stick seems to be more appropriate than a wheel. It also gives a feeling of more precise control over the bird.

A three-point landing using the normal approach of 80 mph was duck soup and the superslow short jobs were only slightly more difficult. With all the flaps hanging out and a 70-mph approach, very little power is needed to control the glideslope. The only thing that must be watched is forgetting how long the gear is and bouncing because of flaring too late. You also have to watch that you don't flare too soon when slow and dirty because the second the nose comes up, you'll run out of speed.

The single-engine characteristics are just as dumpy as the airplane itself. When one engine is shut down, you have all day to do something about it, unlike some high-performance twins that try to bite their tails when one quits. Ron gave me some bush-pilot training on losing an engine on takeoff and I found we could easily recover and fly away, regardless of our takeoff speed, as long as we had about 200 feet of altitude to spare. Shoving the nose down gave us 80 mph, and the other engine would eventually get us up to the 95-mph single-engine climb speed.

The single-engine climb isn't exactly the most fantastic in the world. It will eventually get up to its advertised 6,200-foot ceiling, but the last 1,000 feet is a long time coming. The forthcoming turbocharged version should have a better climb rate and single-engine ceiling, so will be a more useful air-plane.

One thing I definitely didn't like was the inadequate rudder trim. When we actually feathered one engine and charged around the Lomalinda area for a while, I thought I was going to have varicose knee caps. It took all the trim, a lot of aileron and more leg than I had to hold a heading. It could be a real drag flying 100 miles that way. And, although the heavyish ailerons bothered me at first, when we were punching through the clouds on the way back to Bogotá, I came to appreciate the lead-sled stability. As an instrument platform it's great, although I still wished the ailerons were a little more harmonized with the much-lighter elevators.

Although the Evangel isn't exactly a Lear in the speed department, it's practically supersonic compared to most STOL ships. Even at 7,700 feet, we were truing 156 mph at 22 inches and 2300 rpm. With 110 gallons of fuel, this gives a range of 750 miles. With full tanks, you have a useful load of over 1,200 pounds, but you can get 1,500 pounds in and still have two hours fuel aboard.

Now I have seen the Evangel in its native habitat. I've seen it do what it was meant to do, and I'm mighty impressed. There is nothing about it that is commonplace, but at the same time, there is nothing about it that is totally new. It may not be pretty, and it lacks a lot in the sophistication department, but it's a tremendous STOL airplane. It may just be the only truly satisfactory bush twin in the world.