Gimpy Scout
Rich Carr
The following probably falls into the category of freak accident, but
other operators of Bellanca Scout may be interested.
Our Scout, which is used for glider towing, and which has only 200
hours on a rebuilt engine :-(, broke a wheel strut just
outboard of the fuselage the weekend before last. The landing wasn't
hard or in any way different from thousands of other landings. There
may have been an old hairline crack from some previous trauma or defect,
but not that could be seen by a visual inspection.
The pilot wasn't injured. The ancillary damage included:
- broken windscreen from flailing wheel strut
- dented wing leading edge from flailing wheel strut
- bent wing strut from flailing wheel strut
- bent elevator from departing wheel strut
- bent prop from belly slide
- some wing rib damage from belly slide and later transport
- unknown damage to wing spar and engine
The airplane settled on the wingtip and did a 180-degree groundloop,
without too much drama other than having the wheel strut flailing
around until the brake line broke and the strut wandered aft to see
what damage it could do to the tail. We operate mostly on grass,
which may have mitigated the damage to some degree.
The NTSB is conducting metallurgical tests on the wheel strut.
I'll post their findings if they learn anything useful.
Sure seems like it's been a bad year for tugs.
- Rich Carr
TomKnauff
We have operated an 8GCBC Scout for 20 years and absolutely love it as a
towplane. The U shaped bolt that holds the landing gear on has always
been a problem, and had to be replaced every 500 hours. Recently there
are new bolts that replace this old style that eliminate the problem.
Tom Knauff
Knauff & Grove Soaring Supplies
Rich Carr
: What's a "wheel strut"?
Well, I thought "wheel strut" would be less ambiguous than "landing
gear", but apparently I was mistaken.
: We have operated an 8GCBC Scout for 20 years and absolutely love it as a
: towplane. The U shaped bolt that holds the landing gear on has always
: been a problem, and had to be replaced every 500 hours. Recently there
: are new bolts that replace this old style that eliminate the problem.
Which "new" do you mean? There have been several varieties of U-bolts
over the years. Last year, we installed (from Univair, I don't have the
part number handy) the "new" style that, instead of being made from bent
bar stock, is made from two grade 8 bolts and a flat plate under the wheel
strut. So it's not properly a U-bolt any more.
The wheel strut broke about an inch outboard of the U-bolt. There is
some speculation that the bar-type of U-bolt secures the wheel strut
so well that stresses are more highly concentrated in one area.
Since my first posting, the "Scout grapevine" has reported that this
is not an unknown occurrence.
- Rich Carr
MGREENSTNE
annual?
Our club is presently replacing a 9yr-old left, rear spar because of
cracks. It seems the shop that installed it forgot to varnish the thing.
I find it hard to believe that 9 annuals have transpired and no one caught
it. Anyway, as long as the wing literally apart, should we replace the
wing attach brackets or consider any other upgrades before re-covering?
I understand Safe Air Repair has a modified part that is supposed to be
superior to the originals.
Any other suggestions for upgrading the plane will be greatly appreciated.
Mark Greenstone
Assocaiated Glider Club of So. Cal.
MGREE...@aol.com
TomKnauff
bar stock, is made from two grade 8 bolts and a flat plate under the wheel
strut.<
Yes, I believe we are speaking of the same thing. The flat plate is not
rally flat. I never heard of a landing gear breaking on a Scout.
Tom Kanuff
Michael Pilla
We had a landing gear break on our Scout with the "old" U-bolt; fractured
just beyond the U-bolt. As a previous poster hypothesized, we, too, figured
that the the stress was concentrated there ... BTW, the tow pilot that day
made a beautiful landing, I witnessed the incident. He calmly applied as
much opposite aileron as possible, killed the engine, flicked the prop to
horizontal, ... very little damage. Of course, he was a multi-hour ATP,
smooth pilot, ... I doubt that I would have been able to do all that in,
what to me, was very little time. This was about eight years ago, or so.
With the "new" bolt, we had a second gear failure, but it was caused by
tow pilot error. He hit a 4x4 wooden post on TO (don't ask - too long a
story - needless to say that the pilot doesn't tow for us anymore ...) The
post sheared one of the bolts and the end "pin" bolt. The departing gear took
out the "flying wire" under the horizontal stab. The glider pilot released and
made a successful landing. The tow pilot climbed to altitude, burned a lot of
fuel, and did a very decent job of landing with minimal damage. We did get
quite a bit of rib damage when the FBO used a pickup truck to "ferry" the bird
to the shop.
I posted an article a couple of years ago about the "Keystone Cops" antics of
the local fire department. Brief summary, they came and "foamed" the grass
runway! Not only that, they foamed at the very beginning of the runway. I
tried to talk to the fire "chief" about where I predicted the pilot would land
and was told "he'll land where I tell him to". Well, to make a long story short,
a couple of us got a fire extinghisher, just in case, and proceeded to where I
figured he would stop. Sure enough, the pilot makes his approach, prop stopped
properly, the fire dept chaps are frantically waving hands (they had an
aviation handheld, too) and running out of the way as the pilot glides past
the "foam". The plane stops about fifty feet from where we are standing and
does a minor turn pivoting on the "step" (door side). The wing barely touched.
Meanwhile, the Keystone Cops routine starts up; the fire trucks start racing
down the grass runway dragging their hoses behind them. By the time they got
to the plane, we had the occupants out, made sure that the fuel selector had
been shut off, mags/master off, ... Very entertaining since everyone was OK.
Mike Pilla
pi...@espinc.com
steve mc robert
> Any other suggestions to cure ailing Scouts (8GCBC) currently
> undergoing annual?
Yeah!
Replace the mainspar as well!
The wooden spars on the scout/citabria family are pretty notorious for cracks.
If you have it apart, pridence would suggest replacing both.
I think amaerican champion ave an aluminium spar for the scout now, migt we
worth looking at that
Steve
(one of the pilots of NCSA's 8GCBC and also amelia's various citabrias)
Rich Carr
: > undergoing annual?
: Replace the mainspar as well!
This seems to be good advice. You might also put lots of inspection
holes in the fabric so both spars can be inspected well. I remember
someone posting about having a spar crack, which caused the wing to
flex more, which eventually caused the fuel tank to crack and leak.
The fuel leak was how they found out about the cracked spar. And the
rib attachment to the spars is a source of problems and should be
thoroughly inspected every year.
: I think amaerican champion ave an aluminium spar for the scout now, migt we
: worth looking at that
I believe that requires replacing the entire wing (i.e. there is
little in common between the wood wing and the metal wing besides the
final shape) and it must be built at the factory, unlike the wood spar
wing. And the cost difference is 2 or 3x.
- Rich Carr
Jeffrey M. Matthews
Citabria. It bent a few degrees in the first (factory) bend above the
axle--not a lot, just enough so it was apparent that the disc was no
longer clearing the gear leg by the same amount as on the other side.
We swapped it back--the airplane was nearly new--and Bellanca mumbled
something about heat treatment, but I was busy with other things and
didn't follow up.
It may be that on the Scouts in question the gear was a bit soft up
top, allowing just a bit of yielding.
Any chance the original poster could take a close look at the break and
see how far it progressed by fatiguing before it finally broke through?
Jeff Matthews