The L-5 evolved when
someone from the military approached the
Stinson Division of Vultee Aircraft and said
"Build me an airplane that lets me land
short. And make the plane so I can really
see out of the cockpit. And the aircraft has
to be as functional as a jeep. And oh yeah,
while you're doing this, to make sure the
concept really works, make it ugly!"
(Actually, the military asked for a
modification of an existing airplane, but
Stinson said they could build a better one
from scratch, and they did.)
Ugly, obviously, is a
subjective term but, in the case of the
faithful old L-5 Sentinel, it has to be
applied only to aesthetics since, when trees
loom large in the windshield, the L-5 is
truly a beautiful airplane in which to be
aviating. A lot of adjectives can be used to
describe a Stinson L-5, but "petite" isn't
one of them. In fact there is nothing about
the airplane that even comes close to being
dainty. Where the L-5's peer group of Piper
and Taylorcraft putt-putts derived all of
their STOL performance (such as it was) from
65 horsepower and lightweight, the L-5 got
its reputation from pure brute force and
tank-like strength. Its broad snout covers a
six cylinder 0-435-1 Lycoming engine pumping
out 190 Clydesdales. That powerplant is
bolted to a fuselage tubing structure that
looks like it was laid out and executed by a
vocational agriculture trade school, using
tubing twice the size of that in any other
L-Bird, and it is all arc-welded together
with farm machinery techniques. Keeping all
that bulk off the ground are two gear legs
as big around as the average Green Bay
Packer's forearm, and each of these gear
legs is given a least a foot of vertical
travel to transmit big bumps to the inboard
shock struts.
It only takes a minimum
of investigating and common sense to know
the L-5 is the airplane to be flying when
you find you have to go through the trees
and not over them.
From a prospective
buyer's point of view, the wings and tail of
the L-5 are by far the most critical
components since they are made out of wood,
and were part of a wartime philosophy in
which machines such as the L-5 were
considered expendable. Nobody thought these
wooden structures would still be flying over
forty years after the fact, so they have to
be inspected closely.
THE WINGS USE A TYPE OF
STRUCTURE THAT IS almost unique to the L-5
in that they are fabric-covered rib and spar
affairs, but they have none of the usual
drag anti-drag wires. Instead, these forces
are taken out by plywood shear panels which
cover the entire bottom of the wings. This
imparts great strength and weight to the
wings, however, the drain holes at the back
of each rib bay absolutely must be clean or
a huge amount of water is trapped which
eventually can rot all the wood within
reach. The same keep-the-drain-holes-clean
philosophy applies to the tail. The entire
empennage is of plywood monocoque
construction with no brace wires so any
amount of rot or fungus could help your wife
collect on your insurance policy.
If there is one
under-designed portion of the airplane, it
is the brake system. True to late
1930s/1940s design concepts; the brakes are
the old fashion bladder type, ie: a
flattened rubber bagel snuggles inside the
brake drums with blocks around the outer
circumference. As you pump fluid (it must be
mineral oil) into the bladder, it expands
and forces the blocks against the brake drum
which is supposed to stop the airplane. This
is not always the case. When using freshly
rust-free, turned drums with the rest of the
system up to par, the brakes are adequate.
However, as soon as you go up in tire size
the brakes become increasingly marginal
until, when you go out bush-busting with the
10 x 6 tires, your expander tube brakes have
all they can do to hold in place during the
mag check. That is one reason you see so
many of the airplane now fitted with
Cleveland disc conversions.
It
makes almost no difference what your
experience is in aviation or what you are
currently flying, you can be guaranteed of
getting a real charge out of saddling up an
L-5. It is a fun airplane in every possible
sense. In the first place when climbing
aboard, you actually do "climb aboard." You
scramble up the gear leg and the strut,
grabbing a hold of fistfuls of steel tubing
to hoist your butt up into the formed
plywood seat (non-critical materials,
remember?). Once on board you are sitting
really high in what has to be one of the
most starkly finished cockpits you'll ever
encounter. "Military Crude" is probably the
best way to describe the furnishings.
Everything in front and behind you is a maze
of tubing, giving the impression of being
stuck in a chromate green jungle gym. One of
the reasons for noticing the tubing is
because, from the waist up, the airplane is
entirely plexiglass-so the cockpit is
constantly bathed in sunlight and tubing
shadows.
Under your left elbow, a
flap handle that would do justice to a
wheelbarrow juts forward-challenging the
pilot to give it a hefty heave, engaging one
of the notches in the vertical gate in which
it rides. The stick is even bigger than the
flap handle and boot-size rudder pedals are
on the far end of aluminium clad wooden
trays. If the airplane is correctly
restored, an archaic-looking carbon pile
regulator should be occupying all the space
between your feet while your head would be
framed by variations of old black boxes that
held tube and crystal radio sets.
In the late models-the E
and G ambulance version - a crank hangs out
of the overhead directly in front of the
pilot's forehead which, when turned, will
droop the ailerons 15 degrees to make them
into "flaperons" for full span additional
lift in high pucker factor situations. The
ambulance models also have one of the more
hysterical military placards you'll run
across. It states, "Intentional spinning
with litter patients is prohibited." Makes
you wonder what ambulance pilots had been
doing to fight boredom when returning with a
casualty, doesn't it?
O-435 Lycomings are not
known for a mellow exhaust tone. They have a
very distinct tractor sound that fits very
well with the airplane's funky ambiance. You
don't notice the noise on first flight,
because you're preoccupied watching the way
all the glass panels are dancing in unison
to the engine rpm. Most of the rattling and
clattering is a function of propeller
balance. If the airplane has been parked for
any length of time with the prop in the
vertical position, one blade will pick up
water and treat you to a vibrating massage
every time you crank it up. We once ferried
an L-5 that had sat dormant for a few years
and the prop was so far out of balance, the
old B-16 compass on top the instrument
looked like it was full of root beer foam.
When taxiing out, the
high seating position, the jungle gym effect
and all the goings on occasioned by the
Lycoming melt together to give the feeling
you're truly flying a Warbird since there is
absolutely nothing even vague civilian about
this machine. At this point, the L-5 rates
right up there with the Mustangs and Texans
in terms of impact but you are getting a
much bigger bang for the buck-if only
because the bucks are much smaller!
Takeoff is simply a
matter of poking the tractor in the rear and
waiting. Even though the L-5 has plenty of
ponies up front, it's dragging along a
pretty good-size carcass so the plane isn't
going to leap forward. The Lycoming
generates so much wind that you can hoist
the tail in the air almost instantaneously
and, if any flaps are down, you'll be off
the ground almost before you're ready. If a
no flap takeoff is elected, with the tail
hoisted up past level you'll find she'll run
on the mains until ready for a lunch break.
Put her in a slightly tail down position and
she'll growl down the center line until a
suitable speed is found and you're up and
flying. During the takeoff a minimum amount
of attention is required with your feet
unless there is a crosswind, at which point
that tiny rudder will be used to try to make
up for all that side area.
Don't expect the L-5 to
go clawing upstairs like an autogyro. Yes,
technically it is a STOL airplane, but you
have to apply a little common sense. Just
for the heck of it, why don't you give a
little bit of margin and not try to make
this forty-year-old go hopping high hurdles
right off the bat. Incidentally, one
variation of the climb-over-the-trees
routine is possible but not recommended with
the L-5. You can gently cross control,
forcing the plane to climb in a corkscrew
fashion, making believe you're climbing out
of a milk bottle.
If you didn't notice the
lack of control friction on the ground, you
certainly will in the air because the
Stinson L-5 has one of the very best sets of
controls of any airplane from that period.
In typical Stinson fashion, every single
bolt in the control system runs through a
bearing. Even the control stick has a
bearing stuffed into it which reduces system
friction to absolutely zero, totally out of
keeping with airplane's appearance. You'd
expect something a little heavy, a little
crude, a little scratchy, but that is
definitely not the case.
Years ago we took
delivery of a rather bedraggled G-model
after buying it from the Civil Air Patrol on
a sealed bid ($1777.77!). The CAP was
getting rid of the L-5 because they were
having handling difficulties on the pavement
with the big tires. I took the bird around
the patch to make sure everything worked and
was surprised at the controls. On down wind,
the controls felt so good I pulled the nose
up and did two aileron rolls. The colonel in
charge turned to my partner and said, "I've
always wanted to do that but never had the
guts." He should have done it.
In level flight the L-5
is a joy and then some. With the windows
folded down and the breeze whipping around
inside the airplane, you have an incredible
view of everything. Regardless of what
anybody says, there is something to be said
for sitting on top of the world in an
L-Bird. It is a feeling that doesn't exist
in every airplane. Even though the L-5 is
incredibly spartan in creature comforts, a
careful selection of cushions will make the
airplane as comfortable as any you've flown.
Be advised that a good intercom is essential
if you expect to talk to the passenger
because the noise level is very definitely
pre-OSHA and very World War Two authentic.
As a cross-country
machine, the L-5 is several giant notches
above other L-Birds for travelling (with the
possible exception of the L-19). Depending
on how well the airplane is rigged and
you're willingness to lie, the machine will
give you an honest 100-115 miles an hour.
The downside is you'll be burning in the
neighbourhood of 12 gallons an hour, give or
take a little.
The L-5 is fun no matter
what, but especially fun when you come into
land. This can depend on your definition of
"fun." Any airspeed number on final is
perfectly workable . . . if you are off the
ground and flying, you have enough speed in
the L-5. The manual does recommend flaps for
short field approaches. In reality, the L-5
isn't that fussy, but the slower you
approach, the higher the rate of sink and
more throttle will be needed to keep from
flopping on to the ground like a ton of
surplus tank treads. The wing slots give
plenty of aileron at all times so don't
worry about that aspect of slow air speed.
When the flaps and flaperons are out, a near
vertical final approach path can be assumed.
One of the nicest things about the aircraft
is that it can build up an incredible rate
of descent, and the pilot can wait until the
very last second to nail the throttle which
will break the rate of descent almost
instantly-allowing a less than
spine-crushing arrival. As soon as hitting
the ground, stand on the brakes almost as
hard as you like and turn the airplane
around to find only a few hundred feet of
runway have been used. Then you can send
your underwear to the laundry. This ability
to build up a very controllable high rate of
descent makes the airplane much more suited
to getting into short fields than even a
Super Cub, which just refuses to sink at a
high rate.
In more normal approaches
to a paved runway, it is worthwhile to pay
attention to the directional control. The
L-5 is not a difficult airplane to land, but
it doesn't have much going for it if you
lose control. The rudder is small and has a
difficult time overcoming all that vertical
fin area while the stock brakes on big
wheels will not straighten out a
well-developed ground loop. The tail wheel
assembly also needs some looking after to
make sure the unit is doing its share of
steering duties. If you go to sleep at the
switch, allowing the airplane to get away,
the best you can do is just take off at an
angle. If this happens, it's your own fault
since the airplane is doing everything so
slowly.
As a point of
information: The giant 10 x 6 tires look
great on L-5s and allow landings on anything
up to and including railroad tracks but, as
mentioned earlier, they do reduce braking
efficiency which is a minor problem compared
to what they do to landing gear geometry.
When the landing gear extends on takeoff,
the bottom edge of the 10 x 6 tire actually
swings in and is inside the pivot points of
the gear legs. If you make a grease job
touch down, it is quite possible for one
gear leg to go out and the other one pull
in. This creates spectacular ground handling
problems. When flying with the big tires it
is generally better to make a somewhat
sudden arrival, either a wheel landing or a
fairly firm three-point to make sure both
legs spread. As another point of
information, the 10 x 6 tires are reportedly
DC-3 tail wheel tires and they are darned
expensive.
L-birds in general have
become much more popular, a fact easily seen
at Oshkosh '86 where everything from L-2s to
L-19s seemed to be coming out of the
woodwork. Many pilots have discovered the
fun of military aviation isn't limited to
the big iron and big bucks. And they have
discovered the personality lurking behind
the curious looks of the lowly L-5. More and
more of the hulking Stinsons are being taken
out of their glider and tug roles to be
restored, refurbished, and refinished until
they are far superior to the planes which
hopped around the battle-fields of World War
Two. Accompanying its popularity, naturally
is the tremendous escalation in value. Today
it is not unusual to see L-5s in the $20 to
$30,000 bracket when only five years ago
they were a $4000 machine at the very
outside.
As Warbird projects go
there is probably no better value than the
L-5 . . . especially if you're willing to do
much of the work yourself. The supply of
spares is rapidly dwindling but it still
exceeds the demand in most areas. The
airplane requires the builder to check the
wood carefully but that is easily balanced
by the fact the 0-435 Lycoming is a nearly
useless engine since it was used in very few
airplanes, making the engine inexpensive to
buy. There is an STC for a constant speed
propeller but some of the STC parts, ie:
cooling eyebrows, are extremely hard to
find.
Of the various models of
L-5s available, the E and G ambulance
variants seem to be most numerous. It should
be pointed out that the back seats were
second-ary considerations since the
airplanes were primarily designed to carry
litter patients. The earlier models-the As,
Bs and Cs-were designed specifically to
allow observers to paste their noses against
the side window and report troop movements,
etc. Therefore it would seem logical that
those back seats would be much more
accommodating to the average size body.
That's up for verification since most of our
flight time is in G-models. With a G-model
you can forget about the cramped rear seat
and just lay down in the litter position.
Who knows. Put a reading lamp back there or
a portable TV and your wife might even like
it!
If you cut to the bottom
line what you have in the Stinson L-5 is an
incredibly fun-flying airplane that restores
like a really big Cub but has twice the fun
and twice the size for practically no
increase in purchase price. If you really
want to appreciate the airplane as a warbird
put its operating budget up against that of
a T-6 or a P-51 or B-25, or . . . you get
the idea. Go out and put your hands on an
L-5 and you'll find it to be one of the most
overlooked and underrated airplanes you'll
ever have a chance to strap on.