Cno local controller stopped a C150 from entering the runway midfield and canceled takeoff clearance...

Attributes
ACN	585297
Time
Date	200305
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : cno.airport
State Reference	CA
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	ground : position and hold ground : takeoff roll
Flight Plan	None
Aircraft 2
Controlling Facilities	tower : cno.tower
Operator	general aviation : personal
Make Model Name	Cessna 150
Operating Under FAR Part	Part 91
Flight Phase	ground : taxi ground : holding
Flight Plan	None
Person 1
Affiliation	government : faa
Function	controller : local
Qualification	controller : radar
Experience	controller non radar : 6 controller radar : 3 controller time certified in position1 : 5.08
ASRS Report	585297
Person 2
Affiliation	government : faa
Function	controller : ground
Events
Anomaly	conflict : ground less severe non adherence : published procedure non adherence : required legal separation other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance controller : separated traffic flight crew : rejected takeoff other
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Intra Facility Coordination Failure

Narrative:

Runway 26R full length standard departure point. I had just taken position 5 mins earlier on local control, and ground control coordinated a runway 26R at taxiway B departure with a C150, which I approved. A C172 called ready to go runway 26R full length. I instructed C172 to hold short runway 26R for landing traffic, a grumman AA5. Then C150 called ready to go runway 26R at taxiway B. Instructed C150 to hold short of runway 26R, believing he was a BE17 stagger-wing in the run-up for runway 26R full length. Additionally the pilot did not read back his hold short instructions, which I failed to catch. Also, I notified C150 that he was #2 for departure, intending to depart the aircraft after C172 departure. Once the grumman began his rollout on runway 26R, I taxied C172 into position full length. The grumman cleared the runway and I then cleared C172 for takeoff. Believing C150 was the stagger wing full length, I instructed the aircraft to taxi into position and hold. As soon as I realized who C150 was, and where he was at, (runway 26R at taxiway B) I immediately instructed him to stop and cancelled this clearance. I then immediately instructed C172 to cancel his takeoff clearance as well. C150 held short of the runway and C172 stopped his takeoff. Closest proximity was about 2000 ft horizontal. Sometimes controller can become complacent in their job, especially when it is not busy. If I had paid more attention to the coordination with ground control and had listened more closely to C150's initial call-up at runway 26R at taxiway B, and had gotten a readback on his hold short instructions, perhaps I would have recognized the situation as it developed and could have prevented it from happening. It is always important to pay strict attention, especially when just taking control of a position, even if traffic is light, as it was in this situation. Make sure you are aware of the traffic situation, and work your traffic appropriately and accordingly.

Original NASA ASRS Text

Title: CNO LCL CTLR STOPPED A C150 FROM ENTERING THE RWY MIDFIELD AND CANCELED TKOF CLRNC OF A C172 STARTING TKOF ROLL FROM THE APCH END.

Narrative: RWY 26R FULL LENGTH STANDARD DEP POINT. I HAD JUST TAKEN POS 5 MINS EARLIER ON LCL CTL, AND GND CTL COORDINATED A RWY 26R AT TXWY B DEP WITH A C150, WHICH I APPROVED. A C172 CALLED READY TO GO RWY 26R FULL LENGTH. I INSTRUCTED C172 TO HOLD SHORT RWY 26R FOR LNDG TFC, A GRUMMAN AA5. THEN C150 CALLED READY TO GO RWY 26R AT TXWY B. INSTRUCTED C150 TO HOLD SHORT OF RWY 26R, BELIEVING HE WAS A BE17 STAGGER-WING IN THE RUN-UP FOR RWY 26R FULL LENGTH. ADDITIONALLY THE PLT DID NOT READ BACK HIS HOLD SHORT INSTRUCTIONS, WHICH I FAILED TO CATCH. ALSO, I NOTIFIED C150 THAT HE WAS #2 FOR DEP, INTENDING TO DEPART THE ACFT AFTER C172 DEP. ONCE THE GRUMMAN BEGAN HIS ROLLOUT ON RWY 26R, I TAXIED C172 INTO POS FULL LENGTH. THE GRUMMAN CLRED THE RWY AND I THEN CLRED C172 FOR TKOF. BELIEVING C150 WAS THE STAGGER WING FULL LENGTH, I INSTRUCTED THE ACFT TO TAXI INTO POS AND HOLD. AS SOON AS I REALIZED WHO C150 WAS, AND WHERE HE WAS AT, (RWY 26R AT TXWY B) I IMMEDIATELY INSTRUCTED HIM TO STOP AND CANCELLED THIS CLRNC. I THEN IMMEDIATELY INSTRUCTED C172 TO CANCEL HIS TKOF CLRNC AS WELL. C150 HELD SHORT OF THE RWY AND C172 STOPPED HIS TKOF. CLOSEST PROX WAS ABOUT 2000 FT HORIZ. SOMETIMES CTLR CAN BECOME COMPLACENT IN THEIR JOB, ESPECIALLY WHEN IT IS NOT BUSY. IF I HAD PAID MORE ATTN TO THE COORD WITH GND CTL AND HAD LISTENED MORE CLOSELY TO C150'S INITIAL CALL-UP AT RWY 26R AT TXWY B, AND HAD GOTTEN A READBACK ON HIS HOLD SHORT INSTRUCTIONS, PERHAPS I WOULD HAVE RECOGNIZED THE SIT AS IT DEVELOPED AND COULD HAVE PREVENTED IT FROM HAPPENING. IT IS ALWAYS IMPORTANT TO PAY STRICT ATTN, ESPECIALLY WHEN JUST TAKING CTL OF A POS, EVEN IF TFC IS LIGHT, AS IT WAS IN THIS SIT. MAKE SURE YOU ARE AWARE OF THE TFC SIT, AND WORK YOUR TFC APPROPRIATELY AND ACCORDINGLY.

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.

Cno local controller stopped a C150 from entering the runway midfield and canceled takeoff clearance of a C172 starting takeoff roll from the approach end.