HOME-BUILT AIRCRAFT TESTING

Receiving the email with the hot rod Speedster Airplane depicted
above reminded me
of an exploit which I prevent myself from recalling often.
When I was at McDonnell Douglas about 1984, Ziggy, a retired long
time engineer at MDC, asked me if I would test fly his new home built
experimental aircraft. Still being a fearless fighter pilot, I said,
"Hell yes!"I met Ziggy at his hangar in a group of
hangars at the east side of Long Beach airport. The rows of hangars
had narrow taxiways leading to and from the main taxiways to the major
runways. Ziggy was a skinny little guy about five feet three inches
tall, maybe in his late sixties or early 70's. We uncovered the tarp from
his pride and joy airplane and pushed the low wing fighter outside of the
hangar. The streamlined, sleek plane was a classy looking little
winged rocket. It
was a beautiful sight for any aviation enthusiast and seemed to be inviting
me
to get it airborne.
We walked around moving the flight control surfaces and checking
tires, rivets and safety wired nuts. I climbed into the small cockpit
and went through the engine controls and the important gauges. I felt
something cool on my left knee and upon inquiry was told by Ziggy
that the gas tank was
directly in front of me and had a slight leak. I checked that out a
little further but figured it would be all right since the leak was aft of
the engine. Besides this was to be the all important first flight and
we had to get it airborne if only for a quick downwind and landing.
Only after the test hop could the plane be flown slow flight for the
required 25 hours of engine break in.
Ziggy pointed out the heel brakes installation which was all the
little hummer had. He told me how the flight controls worked and I
played with them quite a while as I watched the reaction of the control
surfaces to the inputs from the stick and rudders. The elevators
worked correctly as did the ailerons so I felt the first flight would be
manageable enough to keep me alive for a short test hop.
We cranked up the engine. All systems appeared OK for taxiing
out to the runway, so I told Ziggy to kick the chocks, then step aside and I
would be off. Ziggy said he wanted me to taxi it around the small
hangars for a few minutes to get used to the throttle and the heel brakes.
I didn't like the idea but it was his plane and I said "Ok."
I toiled along doing some "S" turns, using the small rudder and the
heel brakes which had no feel in the small, vertical brake activators
below the
rudder pedals . It was hard to tell if I was deflecting the the
brake pedal until
the brake grabbed and slowed the left or right activated wheel. The
narrow taxiway had a raised center rather steeply sloped for drainage.
I started a U-turn to the right at a walking speed to return to Ziggy's
location about 50 yards back up the taxiway. After 90 degrees of turn
and as I crossed the raised centerline of the taxiway, the right
wheel suddenly released and the aircraft continued straight across the
taxiway with no effect from heeling the right brake. I realized that I
was now along for the ride. I heeled the left brake and shoved the
power up to get the full left rudder reaction to my demand to turn hard
left. The left wheel grabbed momentarily and then released. I
was headed down the side of the taxiway toward the wide garage type door of
a hangar and rapidly picking up speed. I quickly turned off the
magnetos and the electrical key. The prop stopped rotating about two
feet from the hangar door. "WHAM!" The nose of the experimental aircraft punched
through the aluminum hangar door and continued forward until it ended up near the canopy windscreen.
The aircraft had made a silhouette of the aircraft nose and
horizontal prop blades in the hangar door.
I released the lap belt and shoulder straps from the seat and
climbed out. Ziggy was running toward me screaming "Why! Why!" with tears coming
down his cheeks. It was like I had just killed his favorite child.
I checked the propeller blades. Both were bent maybe ten
degrees aft. The damage would require repair that would be quite a job
or replacement . Ziggy arrived still wailing about his beautiful
airplane. I looked into the cockpit and checked the heel brakes.
Plastic 1.5 inch pulleys! The cables had been running through plastic
pulleys the width of the cable but were either too flimsy or inappropriately
aligned to handle the high pressure applied with full braking. The
cable on the right had popped off the pulley and then when full pressure was
applied to the left brake the pulley bent in the direction the cable was
tightened and that cable popped off its pulley too. I had
used far better heel controls on a Lowery organ.
I said, "Ziggy I'm sorry about your aircraft. I'm also sorry
you used plastic cable router pulleys instead of hardened aluminum or steel.
That plastic pulley proved to be a costly substitute." I shuddered as
my mind pictured the flight control pulleys being made of the same malleable
plastic and routed in the same manner as the brake cables.
I helped him pull the airplane out of the hole in the hangar.
The punched out silhouette stood out darkly in the center of the gray
aluminum door. Ziggy and I pushed his plane back to his hangar.
We returned it to where it was stored at the beginning of the episode,
covered it with the same dusty tarp and left the area.
Ziggy called a couple of times wanting my aircraft insurance policy
number. I refused to give him my policy number because it only covered
my C-150 and C-182. I said, "Ziggy, I regret that you will have
to assume the cost of repairs to the garage door and your prop."
Later, I thanked my luck at having a brake cable pulley failure in
that restricted taxi area rather than continuing with the first flight on
Ziggy's prized plane. Dan Colburn, an MDC DC-10 pilot friend, told me
that he had aborted takeoff when he attempted to get Ziggy's little
homebuilt airborne several months before. He said the struts
punched through the bottom of the wing while jarring up and down on the
runway abort. I figured that is how the bird ended up with a fuel cell
over my legs. It was then that I wondered about the CG location with
the fuel weight so far forward! I decided that
Be No
was my plan for the future. There would
Be No
test-flying of home built planes unless on my own aircraft.
Semper Fi
Ed Cathcart
MOFAK
BACK TO BACK WE FACE THE PAST


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