"Oh, God, look where they're camped," Tommy groaned over
the noise of the Super Cub's engine. "Dumb
college kids!"
I smiled, having known where the camp would be, and the
reaction it would elicit from Tommy. It was on a narrow
ledge a few feet above the creek, a product of water
erosion in the distant past. At its head the rugged
glacier moraine lay, while along one side the
tree-covered mountain slope climbed to jagged peaks where
Dall Sheep could be seen feeding. Below it a bit, on the
other side, the creek flowed over its rocky bed, and beyond
the creek the mountains rose once again. Off the glacier
the wind poured, gusts and eddies creating pools of wild
turbulence, and things would only get worse as the day
progressed.
"Coulda used the place downstream," Tommy grumbled,
referring to the nice open spot with good approaches a mile
and a half away, as I began the steep downwind turn, the
sideways drift pronounced. A spot where tight 180 degree
canyon turns in treacherous winds low to the ground were
not necessary. But it was not to be. These kids had come
up from California on a field trip (Alaska 101?) with
their teacher, and were used to having things easy. They
had money, and they expected service. Well, for the price I
was charging for this little extra job, service was what
they would get. Air drops were one of my specialties.
Unfortunately, today's drop, because of the camp's
location, would have to break most of the rules.
Counterbalancing that disadvantage was the fact I had
Tommy's skills to draw upon. Good help in this business is
hard to come by.
Flying my downwind leg, I thought of how I had gone into
the small strip at the entrance to the valley yesterday
morning with the C-180 to pick them up and fly them out as
scheduled. But the kids were not there, only a stick stuck
in the ground and braced with a pile of rocks. On it, tied
with shroud line and marked with surveyor's tape, was a
plastic Ziploc bag. Inside the bag was a note. They were
going to spend an extra ten days in the valley, and wanted
me to airdrop additional supplies. I was also to make a
phone call to California to notify one of their parents of
the change in plans, so no one would send out a search
party. There followed a long list of items to get,
including fresh eggs (air drop?), film, and a couple of
cases of beer. They would pay the charter rate for me to go
into town and do their shopping. All this was fine with me;
that was what I was in business for.
Turning into the wind, passing through my IAF (Initial Approach Fix) window, I
couldn't help grinning at the expression on Tommy's face
when he heard about it, and saw the mountain of supplies
which I had already packed for the drop. And now he was
sitting in the back of the Super Cub with the baggage
compartment stacked full, and the first bundle waiting on
his lap, no doubt still shaking his head.
"Okay," I called to Tommy, by far the best man I had
ever worked with on air drops, a genius on matters of
trajectory, airspeed, and placement. "Open 'er up. We're
ready to go." During World War II he had been an Air Force
bombardier, and his lessons had certainly taken.
Tommy reached over and opened the door of the Super Cub,
letting it fold down, then raised the window and pressed it
into its catch. The wind roared in, picking up a little
dust from the floor, and at that point I turned my complete
attention to flying. When doing air drops, or game
evaluations, the workload has to be split into two
sections: the flying, and the dropping or evaluation. It
is a two-man job. In this business, as the accident
statistics make clear, the pilot who tries to do both does
not survive long.
We descended over the stream bed, the wind rocking us,
approaching the ledge from an angle. Out my window I could
now see the kids waving, standing in a group, but out of
the way, then we were over the ledge and I leveled the
wings for a moment so Tommy could drop the first package
out, surveyor's tape streaming. The turbulence was all I
expected it to be, almost too much, then the package was
out, rolling along the ground, and I wrapped the Cub around
into a steep 180 degree turn, the wingtip just six or seven
feet off the ground, the towering glacier moraine
momentarily close enough to pick out tiny details. Then it
was behind us as I climbed out and let the wind blow us
down the canyon again.
"Well, that's one down," Tommy said in an amused tone of
voice. "Only six more to go." I tossed a quick glance his
way. It was as I expected. He had an ear-to-ear grin, all
traces of his earlier moodiness gone. He was one of those
guys that got more cheerful as the going got rougher and
rougher, a trait that endeared him to me. A good man to
have by one's side when the chips were down. His Air
Force group thought so too.
So we made another pass, and another drop, then another
and another. With each pass the wind got worse, the
turbulence greater, Tommy more cheerful, and me more
focused. Then we were done, and on our way back to my base
of operations. But not to rest. The morning was just
getting started, and we still had a long day ahead of us.
If, as they say, there is no rest for the wicked, then we
were in bad shape indeed; for, during the season, our days
started early and ended late, and holidays were
unthinkable.
(As a minor point of interest, I discovered later that
the packaging and air drop were one-hundred percent
successful: unlike the rules for this type of work, not one
egg was broken.)
* * *
Okay, let's gird our loins and admit it: flying low is a
dangerous practice, frowned on by all right-thinking pilots
except those involved in military, agricultural, and bush
operations. We have the grim FARs (Federal Aviation
Regulations) to remind us of this, and the even grimmer
accident statistics. The military plows into the ground on
a regular basis, the ag boys hit wires and wingtips, and
every season hunters spin in over moose and bear.
Yet, it's gotta be done, no way around it. Low-level
flight, sometimes referred to as nap-of-the-earth, or
contour flying, is just too much a necessity in our
business. Since this is the case, it's best to learn how to
do it right. The techniques are simple and straightforward,
and, when combined with judgment and the appropriate level
of flying skill and aircraft familiarity, becomes
reasonably safe in the hands of an experienced pro.
But what bush situations require low-level flight? Well,
here are a few:
Inspection of terrain from the air prior to
an off-airport landing.
Landing and departure paths that, due to technical
necessity, must hug the terrain.
Air drops of supplies and equipment (a team
operation).
Animal population studies of mountain sheep,
goats, caribou, moose, wolves, and bear (a team
operation).
Big game spotting by hunters (similar to the above,
and also a team operation.
Photographic missions, both still and moving (a team
operation).
Charting prospective roads or trails (a team
operation).
Navigation through remote mountain passes, or along
river channels during periods of marginal VMC (Visual
Meteorological Conditions).
Note that out of the eight listed situations requiring
low-altitude operations, over half of them involve a team
effort. And of those, by far the most accidents are
caused by only one activity: big game spotting. Therefore,
the greater part of this chapter will focus on how to
safely evaluate big game from the air for hunting
purposes. But first we need to take a look at a few of the
general requirements for learning this advanced skill.
General Requirements
During your study of contour flying, there is a serious
danger/temptation of which you must be cognizant. This
danger/temptation (called "The Devil Made Me Do
It!") comes from, and is, a product of the learning curve.
For, as with any other complex skill, such as instrument
flying, or playing a musical instrument with world-class
subtlety, contour flying requires both careful study and
regular practice. Unfortunately, contour flying is more
akin to learning a serious musical instrument, such as the
viola or cello, than it is to instrument flying, and as a
result takes a lot longer before real proficiency is
obtained. Low-time pilots, especially those afflicted with
macho personalities, find this galling, and often push
themselves beyond their current level of ability, hitting
the evening news as well as the ground. It should be kept
in mind that serious contour flying requires true in-depth
mastery of the airplane, and this mastery does not come
overnight.
In studying this subject and developing your skills, you
will over time experience the following:
The development of a precise awareness of what
degree of control lead will be required under various
conditions of weight and ground speed to pass over or
around obstacles while maintaining the desired terrain
clearances.
The development of a precise awareness of what
horizontal clearances will be required for turns through
180 and 360 degrees under varying conditions.
The development of a solid awareness of the shifting
aspects of depth perception under different conditions of
lighting, altitude, and terrain.
The development of a marked ability to maintain
complete concentration on the job at hand -- which is
flying the airplane -- while leaving other
considerations (such as, "My God, look at the size of that
ram!") to your spotter.
These skills, after a period of development that usually
takes a few years, along with a couple of thousand hours in
the various airplanes being used, eventually combine into
an ability to precisely visualize your track within your
mind (exactly as is done with approaches) in advance of the
proposed maneuver, and this is the key to safe contour
flying. How close to the terrain you can safely and
consistently operate is completely dependent upon how
precisely your inward vision corresponds to reality, and
the best pros, when using a Super Cub, are capable of
operating safely -- under calm air conditions -- within
about three feet vertically during straight-and-level, and
thirty feet horizontally during 180-degree turns.
Basic Principles
There are a few basic principles involved in contour
flying, and these principles will go a long way toward
keeping you safe. Let's review them briefly, along with
basic control techniques, before going on to their
practical application in big game evaluation.
The pass (used both in air drops and hunting)
should always be set up as a landing approach, with the
target just to the side of the imaginary strip. The
go-around should be well planned, with flaps, trim, prop,
and power set accordingly. You will, as always, have your
key windows, just as you would for a real approach.
The pass should always be made downhill if at all
possible. This is especially important in narrow canyons,
and was one of the rules that had to be broken during the
airdrop episode described earlier.
Tight downwind turns in strong winds should be
avoided whenever possible. If necessary, they should be
performed without ground reference. Here you are making
your turn in a rapidly moving body of air, and the turn has
to relate to the air mass, not some spot on the ground.
During the turn, sideways drift will be quite pronounced,
and trying to remain over a landmark -- say, a trophy
moose or bear -- will just lead you into tightening the
turn until you stall and go spinning in. This is a real
"gotcha," and manages to get one or two pilots almost every
year. This, too, was one of the rules that had to be broken
during the airdrop, and if you think back on the chain of
events, the sideways drift was every bit as pronounced as
was expected.
Whenever possible, turns should not be made after
the pass until an altitude of approximately 200 feet AGL
has been reached (this joins the long list of rules that
had to be broken on the air drop).
Basic control techniques
Nothing is changed here from standard operating
procedures. During steady-state contour flying,
continue to observe the following principles:
Airspeed is controlled by elevator,
especially in or approaching the area of reverse
command.
Short-term excursions from the basic flight path are
made with elevator at or above 1.3 Vso (stall speed) as long as you
remain within five knots of the target airspeed.
Long-term adjustments, e.g., going from flat to
rising or descending terrain, are made with power.
Flaps. Flap settings are dependent on chosen
airspeed. Under Vfe (maximum flap-extend speed),
half-flaps should generally be used for increased stability
and a more nose-down flight attitude.
Trim. Trim is used exactly the same as always,
to neutralize control pressure once your desired airspeed
has been locked in.
Propeller pitch. When using a constant-speed
propeller during contour flying, select one of the
following settings:
Maximum RPM. Contour flying that will -- or
could -- require full power during the maneuver will demand
full flat pitch prior to its instigation. An example of
this would be when you have to go down in a deep canyon for
an air drop with an immediate climb-out over obstacles
after the drop.
High green. Normal contour flying which requires a
fair amount of maneuvering will work best with the prop set
at the top of the green. This allows a more refined ability
to adjust engine drag or power, as well as the ability to
go to a fairly high manifold pressure on demand.
Low green. Run-of-the-mill contour flying, as you
might do under a clearly-defined 200 foot ceiling down a
flat river valley over gravel bars, will not
require anything but your normal cruise power settings.
Flatland turns
Prior to making any but the most shallow banks during
low-level flight, e.g., around gentle river bends, or when
lifting a wing over a bush or small tree, you are going to
have to climb high enough to make sure you do not drag a
wing tip. For most airplanes operated in the bush, a
general rule of thumb is to use around 25 feet -- half
wing-span, plus seven additional feet for granny. It
doesn't hurt, though, to go a little higher if you are not
in a takeoff or landing maneuver which precludes this, for
you should make a habit of allowing yourself increased
margins whenever the opportunity presents itself; this is
what the more experienced pros do.
Canyon turns
Turns in narrow canyons demand a high degree of
precision. Because of this the fancy diving, climbing
maneuver called the chandelle which the FAA recommends
for this purpose is better left to them and the flight
instructors. A more appropriate maneuver is the simple
power-with-flaps turn, and in a C-180/185 this is performed
as follows:
Slow the airplane to below Vfe.
Set the prop for maximum RPM.
Apply 20 degrees of flaps while slowing to a speed
ten knots above the power-off stalling speed noted in the
airplane's flight manual for a 60 degree bank using this
flap setting. Note that this speed varies with the
airplane's current center of gravity.
Move over to the side of the canyon. The right side
is usually preferable so the turn can be made to the left.
The distance from wing tip to canyon wall under critical
conditions in still air should be no less than fifteen to
twenty feet.
Roll into a steep turn with a bank angle of 60
degrees. Almost full takeoff power will be required to
maintain altitude and airspeed.
When the turn is completed return to normal flight
procedures.
This type of turn, once mastered, will allow you to
operate safely in a very narrow canyon. The turning radius
is naturally determined by airspeed and, therefore,
air-stability conditions. A little practice at altitude
will demonstrate the techniques and its space
requirements. Experience will take care of the rest.
* * *
This winds up our review of the basics, so let's move
forward in time about seven weeks from the kids' air drop
and take a look at hunting season. Hunting season is
always a busy and interesting time of year (in many ways,
much like a circus), and a good portion of the bush pilot's
yearly income is earned during this period.
* * *
We came over the ridge just as the light of early
morning began to flood the narrow valley, the Cessna 180
stable and comfortable in the cool smooth air, and there
the two rams were, just where Ray said they would be. Then
they spotted the source of the disturbance to their
solitude and began to move. Momentarily, I felt a sense of
empathy, then smiled as I saw the path they were picking.
They were old and wise, and had our number.
"What do you think?" Ray called to me over the sound of
the engine, his two German hunters in the rear busy with
their binoculars. "Can we get close to them?"
I watched the rams for a moment as they moved rapidly
along a narrow ledge about 500 feet below the ridge,
heading into a tight V-shaped dead end: an easy place to
get an airplane in, but a hard place to get it out; and far
below them was tumbled moraine leading to a small
gently-flowing creek.
...And that moraine -- how easy to visualize a wrecked
airplane lying there. As easy as visualizing how it could
come to pass...
This was one of those situations that made me wonder
just how much I really knew about rams (at least the very
old ones, close to the end of their days), the depths of
their memory and ability to think beyond instinct. It was
also one of those situations where I wished we were in the
Super Cub, except the Super Cub would never catch them in
time, would never reach them before they made it all the
way to the back of the canyon. As it was, the C-180 would
make it, barely, but was there enough of a margin for
safety? The walls of the "V" were close at that point, and
the 180 degree turn for departure...
...Converging patterns. Calculations going on in that
calm remote part of the mind where a pilot's most serious
flying is accomplished. Then the answer came up, and it
said we were fortunate the air was silky smooth. Another 20
or 30 minutes...
"Yes," I said. "But we'll get only one pass, so make it
do."
Ray looked at me; he, too, was a pilot (his Super Cub
had had an unfortunate encounter with some squirrelly winds
and a gully a few days ago, which was why I was flying
him); then he nodded. He knew the score, had added the
numbers up, knew what they meant. Perhaps that was the
reason behind the grim look on his face. It was a tight
spot, no question about it. Possibly one where he would not
want to be flying himself.
Then we were at our IAF, and I came back on the power,
flattened the prop, set in 20 degrees of flaps and reached
my 60-degree-bank stalling speed plus five knots just as we
came up on the rams, passed them at about 20 feet
horizontally and five feet vertically, then rolled into the
turn with almost full power.
The sloping walls of the canyon rotated around us,
looking almost as though we were about to land on them,
brush them with our wheels, then we were clear and headed
down the valley, leaving the rams behind.
Ray turned in his seat and asked his hunters, "OK?"
Their answer was lost in the sound of the engine, but it
did not matter. Even the glimpse we had caught before
entering the final portion of the approach had been
enough. Needless to say, their binoculars had remained
unused -- as both Ray and I had known all along would be
the case. They had got their close look. A look perhaps
somewhat closer than anticipated.
And Ray flashed me a subtle smile. He knew how tight the
turn had been, how close to the walls we had had to go to
accomplish it. We were fortunate our hunters had found
something to distract their attention. That V-shaped area
of the canyon was not a place to go if
inexperienced...either as a pilot or passenger. It could be
hard on one's dreams. At best.
Our destination now was a gravel bar about 30 miles away
on the wrong side of the river, one suitable for a
heavily-loaded C-180. I would leave them there and return
to base for the Super Cub. With it I could get them within
"reasonable hiking distance." And I would wish them luck --
they would need it. Those two rams, old, wise in the ways
of hunters, intelligent, were a worthy challenge.
* * *
Late afternoon, two weeks later. The air was smooth with
a high overcast, and ahead of us was Chickaloon pass,
closed on the Anchorage side due to weather. The C-180
purred along smoothly and we were starting our climb to go
on-top, join the GKN-BGQ airway, then make an instrument
approach into Anchorage, when one of the Germans pointed
outside the plane at something he wanted to take a look
at. His eyes were as good as his hunting abilities, as
good as the ram he had gotten, and far below us a small
brown spot moved across the muskeg, paused, then began
digging at something.
So we lazily circled down in the fall colors, came to
our IAF behind the bear, a fine Toklat with unusual
markings, and approach began to turn into pass before he
heard us, realized he was not alone, stood, and swatted at
the large mosquito (Alaska size) that had suddenly shown
up. Their ability to move fast, the snake-like sinuous flow
of their movements, never ceases to amaze me. Then the pass
was over and we were at our go-around point, starting our
climb, the rule here, as always, being one pass only, for
it is not good to disturb game without real reason.
"Once more," one of the Germans said. "Please." He made
a slight movement with his hand. In it was a movie camera.
A reasonable request. So I continued on up to 200 feet,
made the turn, passed through our new IAF, made the pass as
the bear once again stood up and swatted at us, a fine
animal, then we were past and had reached the go-around
point. And as the power was gently applied, Ray turned
around and asked, "Do you want to hunt it? We can land back
at the river."
"No," said the German who had not taken the pictures.
"Not this time. Maybe next year."
"Well," Ray said, "you both got good rams. One will go
high in the book. I guess that is enough for one season."
The German with the camera smiled. "We will not be
entering them," he said mildly. "It is the competition with
oneself that counts, not others. That is all that matters."
None of us had anything to say to that.
It was the pro attitude. The best hunters had it, as did
the best pilots.
This excerpt from F. E. Potts' Guide to
Bush Flying: Concepts and Techniques for the Pro
Copyright © 1993 by F. E. Potts, all rights
reserved.