Robert,
I changed from rubber doughnuts to Belleville springs about 5 years
ago, just to end the hassle of replacing the doughnuts every few years.
The Bellevilles worked just fine, but after flying for about 3 years I
noticed that the fuel in the left wing tank was almost to the top when
it was about 1 1/2" from the top in the left tank. I measured from my
wingtip lights to the floor in my hangar, and found about a 5"
difference, just as you did. At my next annual my mechanic and I
checked the Bellevilles and found one disk flattened out. We called
Univair and they said that this does happen, but rarely. They sent us a
whole new stack, and we replaced those on that side. I suspect that you
have the same problem.
Syd
robertbartunek wrote:
A week or so ago I wrote a blurb on the flyin' part of the Ercoupe
board and told about a really radical crosswind takeoff from a field
in West Texas. I had confidence in the Coupe because of all I had
read about the excellent crosswind handling characteristics the
machine displays. In my case, after thinking about it more and
listening to some of the later inputs by members of this group, I
think I have put together the chain of events that led to my near-
runway departure on takeoff.
Members have mentioned that the tail height sittng on the ramp should
be 75 inches. I measured my tail height today and the right tail
height is 71" and the left tail 69". Hmmmm. Airplane crooked,
better measure wing heights and found right wing at 51" and left wing
at 46" both measured from the bottom of the wire holding the nav
light lens on. So the airplane has a positive angle of attack and a
left bank just sitting on the ramp.
Another little factoid I remember was the wind speed during takeoff,
according to AWOS was 260 at 30 knots and the takeoff runway was 17.
90 degree crosswind at 30, no big deal, hold nosewheel pressure, pop
it off at 50-60 and away we go. Ercoupes do very well in crosswinds,
remember?
Now I'm not saying that the information on AWOS was wrong because I
interpreted the information to tell me that I had a very stout right
cross for takeoff. What I recall now adds to the events and was
probably the ultimate straw leading to something bad happening.
I did a walk around and untied the airplane but as I was about to hop
on the wing, a pretty good gust swung the nose of the coupe around
toward the wind. I steadied the bird and two other guys standing out
on the ramp came over to help and held the plane while I got in and
started it and began my taxi. Taxiing was no sweat because the lower
wing was into the wind and everything seemed normal until the
takeoff. After about 300 ft of takeoff roll the plane really wanted
to weathervane to the right, into the wind, so I added some left yoke
pressure to steer straight down the runway. That's when the right
wing came up pretty abruptly. The natural tendency is to counter the
roll with yoke pressure to the right to lower the wing but that also
steers the nosewheel steering to the right which magnifies the effect
of the right crosswind by turning the nosewheel to the right, and
yahoo, right runway edge here we come.
So I had an airplane with the high wing into the crosswind, an
airplane that sat slightly nose up, and a crosswind that was probably
stronger than advertised.
After takeoff, I headed east at about 500' agl because that would put
me at 1500 agl when I reached my destination and the terrain I was
flying over was nothing but runway, so why climb. Anybody ever flown
over the Texas Panhandle?
After level off, the groundspeed on my trusty GPS was 148 mph, so I
would guess that I had more like a 40 mph crosswind on takeoff
instead of 30.
See how the little things add up?
Tomorrow, I take the bird in for an annual and the tail/wing heights
will be looked at closely. I noted in the aircraft log that
Bellville springs had been installed a few years ago.
Anybody know what might be needed to level this thing up?
Robert Bartunek
