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193
Number 194 July 1995
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From NASA's Aviation Safety Reporting System�
Mis-understandings, mis-interpretations, miscommunications—
all can lead to a variety of adverse
consequences.
misunderstanding about IFR clearances led to an
unauthorized flight into IMC.
■ Weather conditions were 1200 feet overcast, 4 miles
visibility in fog, with tops at 3200 feet and visibilities 40+
Among the Mis-sing
Fowled
An ASRS report illustrates how a
miles on top. I was cleared for a descent from 4500 feet for a
VOR approach into XYZ, and told to maintain VFR. The
next Approach facility cleared me for the VOR approach. I
flew the approach as published, and at the final approach fix,
Approach told me to squawk VFR and switch to Advisory. I
squawked 1200 even though I was in IMC conditions at the
time. About 4 miles from XYZ and in VMC, I told Approach
that I would like to cancel IFR and proceed VFR. At that
time they told me that I was never IFR.
A clearance for an approach using a particular navaid does
not qualify as an IFR clearance. The reporter could have
picked up on two clues—first, the instruction to maintain
VFR, and second, the VFR squawk.
Yikes!
A mid-air collision is many pilots’ worst nightmare. In the
following report, classified as an incident, the pilots of both
aircraft were very fortunate to have experienced a mid-air
with such minimal consequences. The pilot of a low-wing
aircraft had been informed of glider traffic at his airport of
intended landing, but did not have the traffic in sight. The
pilot switched to UNICOM, reported crossing overhead, and
began his descent on crosswind.
■ As I started to turn onto downwind, I felt a bump...as if
the wheels struck an object. My wheel struck the glider’s
canopy, and my right wing grazed the glider’s right wing.
Both aircraft landed with minor damage.
Both glider pilots were looking for me. I could not see the
glider beneath me turning onto downwind [at the same time I
was]. I was not aware the glider was in the pattern. A Tower
would have averted this incident, which was close to being a
tragic accident.
Actually, adherence to recommended safe operating
procedures would have averted the incident. Descending to
the traffic pattern altitude outside the normal pattern
decreases the likelihood of descending onto another aircraft.
In addition, the 45-degree entry to the downwind leg is
helpful in sighting other aircraft in the pattern. In this
incident, neither procedure was used.
An instructor making a point to his student about forced
landings was reminded of another important point—that of
thorough pre-flight preparation, including a careful review of
charts. The student, presented with a simulated engine
failure, went through all the right steps for selecting a
landing site and securing the aircraft in preparation for the
landing, when...
■ ...at approximately 100 feet AGL, we initiated a goaround.
Upon application of power, many birds took flight
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