Less than standard separation between 2 small aircraft aircraft. Operational error.

Attributes
ACN	133409
Time
Date	199001
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : lbb
State Reference	TX
Altitude	agl bound lower : 0 agl bound upper : 100
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : lbb
Operator	general aviation : instructional
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	climbout : takeoff landing other other
Flight Plan	None
Aircraft 2
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	climbout : takeoff
Person 1
Affiliation	government : faa
Function	controller : local
ASRS Report	133409
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : student
Events
Anomaly	conflict : ground less severe non adherence : required legal separation
Independent Detector	other controllera
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 100
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Small aircraft X was cleared for touch and go on runway 26. Small aircraft Y was cleared for takeoff on runway 17R. X crossed the threshold of runway 26 before Y crossed the intersection of the runways. No action was taken once the situation was observed to be imminent because: a) neither aircraft was likely to see the other, B) any xmissions made would not have increased the separation (never less than a mi and never at the same altitude). The situation was safe, but not legal and corrective action was as likely to confuse as it was to correct. Contributing factors: a) small aircraft X changing point of turn to base. B) small aircraft Y slow to take off. C) controller running too close to allow for a and/or B. To prevent: a) stop touch and goes when busy. B) spread spacing to the point they cannot cause a problem with pilot changes. C) delay departures. At the time the problem was discovered small aircraft X could have been sent around or told to make a full stop and hold short of 17R. Either instruction would have come on short final with a student flying and it was believed safer not to talk to him at all.

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN 2 SMA ACFT. OPERATIONAL ERROR.

Narrative: SMA X WAS CLRED FOR TOUCH AND GO ON RWY 26. SMA Y WAS CLRED FOR TKOF ON RWY 17R. X CROSSED THE THRESHOLD OF RWY 26 BEFORE Y CROSSED THE INTXN OF THE RWYS. NO ACTION WAS TAKEN ONCE THE SITUATION WAS OBSERVED TO BE IMMINENT BECAUSE: A) NEITHER ACFT WAS LIKELY TO SEE THE OTHER, B) ANY XMISSIONS MADE WOULD NOT HAVE INCREASED THE SEPARATION (NEVER LESS THAN A MI AND NEVER AT THE SAME ALT). THE SITUATION WAS SAFE, BUT NOT LEGAL AND CORRECTIVE ACTION WAS AS LIKELY TO CONFUSE AS IT WAS TO CORRECT. CONTRIBUTING FACTORS: A) SMA X CHANGING POINT OF TURN TO BASE. B) SMA Y SLOW TO TAKE OFF. C) CTLR RUNNING TOO CLOSE TO ALLOW FOR A AND/OR B. TO PREVENT: A) STOP TOUCH AND GOES WHEN BUSY. B) SPREAD SPACING TO THE POINT THEY CANNOT CAUSE A PROBLEM WITH PLT CHANGES. C) DELAY DEPS. AT THE TIME THE PROBLEM WAS DISCOVERED SMA X COULD HAVE BEEN SENT AROUND OR TOLD TO MAKE A FULL STOP AND HOLD SHORT OF 17R. EITHER INSTRUCTION WOULD HAVE COME ON SHORT FINAL WITH A STUDENT FLYING AND IT WAS BELIEVED SAFER NOT TO TALK TO HIM AT ALL.

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.