the BD-5 Actually Flies
by Budd Davisson, courtesy of
www.airbum.com
Okay all
you skeptics out there (and I was one
of the strongest), let it be known
here and not that, not only does the
BD-5 fly, but about 90 per cent of us
owe Jim Bede a gigantic apology. He
has managed to build a tiny little
wing stability platform that shows
more thought ingenuity and out and out
genius than anything general aviation
has seen for years.
It still has some bugs to iron out in
the engine department but, other wise,
the BD-5 , as we flew it, represents
the first quantum leap forward in
light aircraft design since WWII. As I
was hoisting my fanny up out of the
little cockpit after flying it, all I
could think of was, "Jim Bede, I'm
sorry for all those rotten things I
said about you and your airplane."
He's made a believer out of me.
You have to be a yak-herder in the
Himalaya boonies not to know the saga
of the BD-5 by heart. Every magazine
with a circulation of more than 15 has
run at least one story about the BD-5
and it's rotund, hyperactive
designer-builder-promoter, Jim Bede,
and therein may lie one of the
original seeds of the great Bede
controversy, as it now rages. Too much
was said too early in the game,
promises were made, performance
figures quoted and money taken. So,
when things didn't go like clockwork,
the BD buying public got a little bit
ticked off. (Witness the lynch mobs
lurking in dark corners at Oshkosh,
lying in wait for him.)
There is no doubt that many early Bede
claims were optimistic. No they were
more than optimistic, they were
outlandish (270 mph was promised t one
point).
I sat in the bleachers with the rest
of the aviation community and watched
the whole Bede experience develop. I
booed and hissed right along with the
others. I can clearly remember
receiving a three-view of the very
early Micro and my first impression
was that Jim Bede was absolutely and
irrevocably out of his tree. The
entire thing just wasn't possible. All
of us sidewalk engineers gawked at the
early V-tailed fibreglass prototype
and nodded knowingly. It was generally
agreed that, if it did fly, it would
have the inherent stability of a bongo
board and the handling characteristics
of a Whiffle ball.
After a while the old "it will never
fly" crowd changed their tune to "it
may fly but only a NASA test pilot can
handle it," You see, had to find
something else to gripe about because
that chainsaw with wings was flitting
around at far too many airshows for us
to maintain credibility in the face of
fact. It did fly and appeared to fly
well.
Naturally, there is only one way to
find out if "Joe average pilot" can
fly it and that is to snuggle down
into it and go aviating, so we asked,
"Can we fly your airplane?" The answer
was, "of course." First Bede had to
check a few things out. Next month
maybe. When it was next month, the
answer was in a few weeks, then it
went back up to months. This went on
for over two years. It looked like a
classic holding action against a press
that might leak the news that the BD-5
was nothing more than a cylindrical
coffin with retractable handles.
At Oshkosh the word came down: we
could come down to Newton and fly his
airplane at our convenience. At our
convenience, really? We didn't begin
getting excited until we called him
and he said, "Sure, how about
tomorrow?"
The second I stepped off the plane at
Wichita, I knew it was trouble. It was
blowing about 35 knots in the middle
of the night. They were probably
chaining the cattle to the ground. The
next morning Les Bervin, BD test
pilot, confirmed our suspicions and
allowed as how it wasn't the best day
to be flying the BD-5 for the first
time, but it was okay to fly the BD-5T
trainer. There two-ton Tinker-Toy
trainer is almost as ingenious as the
BD-5 itself. Using a systems of
springs and booms, they have hung a
clapped-out BD-5 (early victim of a
journey through a ditch) on the front
bumper of a Dodge pick-up truck. The
springs counterbalance the weight of
the boom almost exactly, so any lift
generated by those ridiculous little
wing panels will life it off the
ground and let you shoot
touch-and-goes and make gentle turns
to your heart's content.
Looking at the truck, the airframe and
the rail-straight windsock, I
suggested we draw straws. I lost. The
other two guys locked themselves in
the truck cab, leaving me to be the
first to find out what a Dodge-powered
BD-5 was like. Rich strapped me into
the trainer and explained rotations
speeds and offered a few helpful hints
as he was putting the headset down
over my twitching ears.
My first flight in the trainer was
sort of hop, jiggle, bounce, scrub. I
over-corrected, over-rotated and
over-wound just about everything. the
side stick initially seemed incredibly
sensitive, then, magically, about half
way down the runway things seemed to
smooth out. The second run had me
hopping off the ground like a frog on
a hot rock, but by concentrating on
the runway in front of me and
forgetting where my hand was resting,
I could even keep the wing down and
cancel out the crosswind, which by
this time was a solid 40 knots. The
third time around I rotated off almost
like a normal airplane. I was flying
big gentle S-turns all the way down
the runway while I called out my
height to Rich in the cab to see how
close I was. The fourth run was
unnecessary; I felt like I knew what I
was doing. The rest of the guys had
very nearly the same reaction.
What the BD-Dodge
combination showed me was, first of
all, takeoff happens very quickly and
it is easy to over-rotate. then it was
even easier to over-rotate the
rotation, which caused a little bit of
saw-toothed flight for a while. the
most important thing I learned was
that by focusing my eyes straight
ahead and flying it like one of those
fly-by-wire games in the bus depot, I
could eliminate most of my
over-controlling difficulties. It is
strictly a visual affair because there
is absolutely no fell or pressure in
the control stick. We each had a
chance to look through the flight
manual, but Les sat us all down and
went methodically down the list so
each of us knew what to do when.
Besides all the usual numbers, there
were a few things I found even more
important to remember. The first was,
if the engine quit, we couldn't
restart it. This particular bird had
the starter ring gear removed and they
had to fire it up with a pull-cord.
Also, the clutch and the drive system
is such that the prop freewheels when
the engine isn't running. Even though
the prop is turning, the engine isn't.
that didn't sound too bad, but then he
mentioned that if we touched zero G
for even a second, the float-type
carburettor they had temporarily
installed would choke the engine
deader than a mackerel. well, if
nothing else, I realized that kind of
information would make me tiptoe
around while doing aerobatics.
There aren't a whole lot of airplanes
around in which you can actually
retract the landing gear while sitting
on the ground for cockpit check, but
then, there aren't too many airplanes
six guys can pick up and put on
sawhorses either. That is where we sat
while familiarizing ourselves with the
cockpit. From the instant I
stiff-legged myself down into the
cavern underneath the panel I was
knocked out by the logic of the
cockpit. Everything is in the right
place, easy to use and figure out. The
fuel controls are ahead of the left
console and all the electrical stuff-mags,
master, etc.- on the right one. the
landing gear is a healthy looking
T-handle affair that would look more
at home in a jacked-up GTO. It juts up
between your legs about where the
control stick should be and the flap
handle is right next to it. The
control stick is shaped like a Baby
Ruth you had squeezed in your hand,
and sticks up out the right console.
Only the trim, which is right next to
the throttle, and the stick appear or
feel anything but perfectly placed.
Once up on the sawhorses, we amused
ourselves with the landing gear. It
takes a healthy tug to get it started
up, but more than the, you have to
keep it moving so the inertia of the
gear helps to get the handle over
center. If you don't keep your
shoulder behind it, it will stop
halfway and you'll never get it up.
When you pull and keep on pulling, you
are rewarded (or surprised) with a
healthy whack on the bottom of the
fuselage. There is absolutely no doubt
that the hear is up or down. When it
slams into position, the airplane
practically jumps off of the
sawhorses. It's like being inside of a
giant switchblade. Les had us do it
without moving the stick so we
wouldn't be jumping around in the air
when retracting the gear. it was good
practice, but it didn't work.
we figured the way to beat the wind
was to get up before it did, which
still didn't work. At 5:30 the next
morning, with my eyes clamped shut to
keep my precious bodily fluids from
leaking out, I staggered to the door
to see that it was still blowing up a
mini-storm outside. We thought we'd
had it, but Les stuck a finger into
the breeze and said, "Roll it out;
let's go flying." A few minutes later
I found myself fiddling with chokes,
mixtures and mags and hopping over
expansion joints in the taxiway as I
wended my way down to the runway. In
taxiing, the engine idled at nearly
3000 rpm; it sounded like a lawnmower
trying to run me down. I pressed the
transmit button on the top of the
throttle and said, "I'm ready to go."
My headphones answered, '"Good-bye."
Looking back at it, I'll have to admit
to not remembering much about that
take-off because it all happened so
quickly. The engine revved to about
5000 rpm immediately and the 52 hp
behind me started kicking me down the
runway at an astonishing rate. At 50
mph I started picking up the nosewheel,
which skipped a couple of times; as I
rocketed to 60-65 I was up and away.
The take-off was almost toy-like. I
bobbed around a bit, more from
surprise than from anything else. As
soon as I started watching what I was
doing and got out of ground turbulence
at 10 feet, it settled and felt almost
as solid as a Cessna 150 would have in
the same wind. At around 75-80 I
reached down for the landing gear,
completely forgetting the keep-on-pullin'
retraction technique. I gave it a
cursory jerk. As the handle came to a
halt in the midway position, I called
myself a few choice names and rammed
it forward to lock it down again.
While I was busy jamming the gear
handle, I forgot where my right hand
was and unconsciously tweaked the
stick. This caused the airplane to
jump around. When I gave the gear a
healthy pull it obediently leaped into
the wells. As the gear came up and I
let the flaps up slowly, the speed
wrapped up to 1-- mph pronto.
The best-rate-of-climb speed was 90
mph, but I was keeping it at around
100 for cooling. We climber 1200 feet
per minute with 52 hp blatting away
behind, the tack working its way up to
6500 rpm and the 182 camera plane
disappearing fast.
The most surprising thing about those
first few minutes of flight is that
everything seemed so normal. I didn't
even bother to look out at those
tooth-pick wings or marvel at the
incredible visibility. It just felt
that was the way airplanes should be
this was an airplane and it just flew
like one. I wanted it to feel strange
and exotic, but things fit together
too well.
Set your hand on the chair next to you
right now and make a list. Now wiggle
it left-to-right while keeping your
elbow stuck to the chair. If you don't
move the top of our fist more than
half an inch or so, you'll see what it
is like to fly a BD-5. there is no
noticeable resistance and practically
no movement of the stick. If you
twitch your hand an inch to the side,
you've just done a roll. Move it an
inch or so back and you loop. Now,
that sounds like it's sensitive, but
for some reason or another it doesn't
work out that way. It's got to be the
most natural way to shepherd an
airplane around I have ever seen.
Les had sworn that the stalls were
nothing to write books about and he
was right. In any configuration it
would shake, buffet, leap and groan as
you crept up to the stall, One wing
would unload as it would roll off in
one direction of the other. I'd keep
the stick completely back and porpoise
ahead, using aileron and rudder to
keep everything square with the world.
the instant-I mean the very
instant-the elevator was released, the
little beastie would be flying again.
Clean it was stalling at about 65, and
dirty at about 55.
I cursed the zero-G carburettor as I
sucked the nose up and tweaked my hand
left to watch the sky and ground swap
places. With just a little inverted
capability-just a couple of
seconds-you could drag the rolls out
into long, sensuous affairs over which
you'd have infinite control. I'll have
to wangle another flight when they put
the new carburettor on, I guess. you
can roll fast or your can roll slow,
four points or eight, left or right,
and barely move your hand. To the
right, rolls are just a little more
difficult, because your wrist works
more naturally inboard than it does
outboard. Full aileron deflection is
only about a 2-inch twist of your
wrist, but you almost never need it.
The roll rate is fast, about 150
degrees per second, which is just a
tad slower than a roundwing Pitts. I
can't begin to describe the total
precision of these controls. They
don't even come close to being
sensitive, but they put more control
in the palm of your hand than any
other airplane I know.
Now, almost nobody reading this is
going to believe my next statement,
yet it's absolutely true: the BD-5 is
one of the most stable little
airplanes flying. When I'd set it up
hands-off and then pulse the
stick-just bash it forward or back-the
nose would come up and then-bam-come
back to level and not move again.
There was almost no sign of
oscillations of any kind. The same if
true of yaw: punch and rudder, and the
nose snaps back as soon as you let go.
In roll it seems just a little more
neutral. The wings stay pretty much
where you put them. I tested all this
stability out by grooving around for a
while as I used both hands to adjust
my headset and boom mike, to eliminate
some communications problems (which
turned out to be my inability to read
"volume" one the radio face).
The BD-5's high thrust line means a
nose-down pitch with poser. (the nose
comes up when you back off the
throttle). Speed and power changes do
give a fair amount of trim change, but
I had been flying for a while before I
noticed that I had been unconsciously
moving the trim control with the thumb
of my throttle hand all along.
I knew Bede had done complete spin
tests, and Les had told us to go ahead
and spin it. But I'll admit that I put
spins off until I worked up my nerve.
Finally, I got the power back, got the
stick back, and kicked rudder as it
stalled. Instantaneously it snapped
over on its back and twisted downward
into a near-vertical spin. the first
turn was more of a snap roll, the
second turn was very oscillatory, with
the nose coming up fairly high. They
the nose dropped to about 60 degrees
and stabilized in a very fast spin.
Sixty degrees, by the way, looks like
you're going straight down. Les had
said that the airplane had a distinct
stick-free spin mode, here the reduced
drag of neutralize controls caused the
speed to increase and the spin to wrap
up very tight. That's why it needs a
classic NACA spin recovery: bash the
stick well forward and nail opposite
rudder hard.
Naturally, I managed to botch up the
recovery. I moved the stick forward
too slowly at the end of three turns,
and it immediately cracked around in
two more lightning-fast turns before I
got the stick far enough forward. I
recovered in less than half a turn,
going absolutely straight down. I
instinctively loaded a slight positive
G on it to keep that carburettor
happy, and, in so doing, got a slight
secondary spin in the other direction.
But that topped almost immediately.
the second time I spun it, I did what
Les had told me to do, and it popped
out instantly. It's a very
predictable-spinning airplane, but you
have to move like you mean business to
stop it where you want it.
On the way back into the pattern, I
made a couple of speed runs at 5,000
feet AGL. (9,000 feet density altitude
for that day). I was showing an even
155 mph cruise, and that works out to
177. Later, Peter did the same thing
down lower, at 1,000 feet, and got a
solid 175 mph indicated, which works
out to 188.
I knew I couldn't stay up all day and
avoid the landing. I flew a wide
360-degree overhead pattern, coming
downwind at 100 mph and base at 90. It
had taken me forever to get into the
pattern, because power off, at 85 mph,
I was only showing about 380 fpm
descent. I was beginning to wonder
about getting down before lunch. Les
had said the gear worked like
spoilers, and when I dropped it, I saw
what he meant. With gear and flaps
down I had to use just a tad of power
to fight the wind as I turned final
for the taxiway we were using the
land. (It was smoother than the
runway.)
The pitch stability came in handy for
holding 85 right on the money as I
jockeyed the power just a little to
stay on glide path. I kept reminding
myself what the view over the nose in
the trainer had looked like as I came
closer to the ground. the wind tried
to boggle me around but a tweak here
and a tweak there kept everything
perfectly lined up. As the pavement
started to get closer, I gently (very
gently) started to flare. The second I
moved the nose, the airplane stopped
coming down. So, I relaxed a bit and
started feeling for the ground. Lower.
Lower. Lower. Suddenly I knew I was
only a foot or so off and I started a
game with the wind. I tried to hold it
up as the wind stared to bat me
around. Plunk, and the mains were on.
I tried to hold the nose hear up, but
the flaps were too much for it and it
dropped onto the pavement anyway. We
were on the ground at around 60 mph.
The roll out was easy to control with
the rudder and I didn't need to use
the brake at all until I was ready to
turn into the parking area.
Well, I think we've discovered what
kind of pilot it takes to fly the
BD-5. Any proficient 150-hour pilot
could learn to handle it, but only if
he had already developed certain
skills and mental attitudes. He'd
better be an accurate pilot. He can't
make vague, unmetered control
movements or be only fuzzily aware of
what he sees over the nose. The
airplane is capable of absolute
precision, and to make consistently
smooth landings and takeoffs, the
pilot must use that precision. Most
pilots are sloppy; they'll have to
de-slop themselves before the fly the
Five. the guy who takes great pride in
making nothing but squeakers right on
the centreline won't have any trouble
at all. This type of mental attitude
is totally independent of flight time,
and can be present or absent
regardless of how fat the logbook may
be.
Flying the trainer would be the best
bet for transitioning into the Bede.
There you get the super-low ground
attitude, seating position, and
control response all in one package.
Otherwise a glider-especially
something like a Blanik or a 1-34-will
give you a perfect learning situation
for the supine seat and ground-hugging
landing attitude. an older Yankee
would give you the basic control
responses-the brake-only directional
control, and similar stall
characteristics., (the BD-5's are far
better.)
Asked how I feel about it, I can only
say that now I wish I hadn't let my
scepticism keep me from putting down
my $400 deposit for a production
model. Oh, well . . . Bede probably
has something else up his sleeve, and
you can bet I'll put my money where my
doubts are this time.
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