Reporter has near midair collision with another landing aircraft at about 100 ft.

Attributes
ACN	303129
Time
Date	199504
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : 9k4
State Reference	MO
Altitude	agl bound lower : 100 agl bound upper : 100
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	descent : approach landing other
Flight Plan	None
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	landing other
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : commercial pilot : instrument
Experience	flight time last 90 days : 50 flight time total : 400 flight time type : 200
ASRS Report	303129
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	conflict : nmac other spatial deviation
Independent Detector	other other : unspecified
Resolutory Action	other
Consequence	Other
Miss Distance	horizontal : 50 vertical : 50
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While engaged in practice for the upcoming nifa national competition, myself and another aircraft had a near midair collision.I was the trailing aircraft, and had the aircraft in front of me in sight while on final approach to runway 36. I assumed that the other aircraft was making a low approach to the message drop targets that parallel the runway on the right side. The other aircraft passed above and to the right of me, and the view of the other aircraft was blocked. I continued my approach until about 100 ft AGL, when I saw ground observers waving me off. I initiated a missed approach and climbed out. I saw the other aircraft behind me landing on the runway. This was the first indication I had that the other plane was landing. Neither aircraft saw each other at the point of closest approach, but ground observers estimated closest approach at 50 ft. Probable causes include poor decision making on my part, with failure to keep the other aircraft in sight at all times the primary error. Contributing problems include a malfunctioning radio in the other aircraft, which hampered communications. In the future, better ground briefings before flight practice should preclude the need for false assumptions and errors.

Original NASA ASRS Text

Title: RPTR HAS NMAC WITH ANOTHER LNDG ACFT AT ABOUT 100 FT.

Narrative: WHILE ENGAGED IN PRACTICE FOR THE UPCOMING NIFA NATIONAL COMPETITION, MYSELF AND ANOTHER ACFT HAD A NMAC.I WAS THE TRAILING ACFT, AND HAD THE ACFT IN FRONT OF ME IN SIGHT WHILE ON FINAL APCH TO RWY 36. I ASSUMED THAT THE OTHER ACFT WAS MAKING A LOW APCH TO THE MESSAGE DROP TARGETS THAT PARALLEL THE RWY ON THE R SIDE. THE OTHER ACFT PASSED ABOVE AND TO THE R OF ME, AND THE VIEW OF THE OTHER ACFT WAS BLOCKED. I CONTINUED MY APCH UNTIL ABOUT 100 FT AGL, WHEN I SAW GND OBSERVERS WAVING ME OFF. I INITIATED A MISSED APCH AND CLBED OUT. I SAW THE OTHER ACFT BEHIND ME LNDG ON THE RWY. THIS WAS THE FIRST INDICATION I HAD THAT THE OTHER PLANE WAS LNDG. NEITHER ACFT SAW EACH OTHER AT THE POINT OF CLOSEST APCH, BUT GND OBSERVERS ESTIMATED CLOSEST APCH AT 50 FT. PROBABLE CAUSES INCLUDE POOR DECISION MAKING ON MY PART, WITH FAILURE TO KEEP THE OTHER ACFT IN SIGHT AT ALL TIMES THE PRIMARY ERROR. CONTRIBUTING PROBS INCLUDE A MALFUNCTIONING RADIO IN THE OTHER ACFT, WHICH HAMPERED COMS. IN THE FUTURE, BETTER GND BRIEFINGS BEFORE FLT PRACTICE SHOULD PRECLUDE THE NEED FOR FALSE ASSUMPTIONS AND ERRORS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.