|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Locale Reference||airport : tjsj.airport|
|Affiliation||government : faa|
|Function||controller : approach|
|Qualification||controller : radar|
|Experience||controller radar : 7|
|Independent Detector||other controllera|
|Resolutory Action||none taken : unable|
|Problem Areas||Airspace Structure|
The agreement made between the sju tower and the san juan cerap about the 7 mi in trail at the marker and at 170 KTS; represent an unsafe condition for the R1 controller unless there is an extensive traffic flow in effect before the controller; can provide those 7 mi. The R1 controller only has 18 mi on the final approach course for any of the approachs for runway 8. That number means that the R1 controller can only have 2 aircraft established on that final approach course. If R1 has to provide 7 mi; he has to establish the aircraft in trail using more than 7 mi to allow for compression. For example; 2 B757's on final; the first one will start reducing at the FAF while the other will be at 170 KTS. The R1 controller will need to establish them at least 8 mi apart. Same scenario but with a C402 in front of the B757. The C402 can reduce to less than 90 KTS. The R1 controller would need to establish the B757 at least 9 mi behind the cessna. All of this constitutes an increase of workload and a decrease in safety.
Original NASA ASRS Text
Title: A CERAP CTLR EXPRESSES CONCERN ABOUT A LOA BTWN APCH CTL AND THE TWR REQUIREMENT TO PROVIDE 7 MI IN TRAIL SEPARATION FOR ACFT LNDG AT SJU.
Narrative: THE AGREEMENT MADE BTWN THE SJU TWR AND THE SAN JUAN CERAP ABOUT THE 7 MI IN TRAIL AT THE MARKER AND AT 170 KTS; REPRESENT AN UNSAFE CONDITION FOR THE R1 CTLR UNLESS THERE IS AN EXTENSIVE TFC FLOW IN EFFECT BEFORE THE CTLR; CAN PROVIDE THOSE 7 MI. THE R1 CTLR ONLY HAS 18 MI ON THE FINAL APCH COURSE FOR ANY OF THE APCHS FOR RWY 8. THAT NUMBER MEANS THAT THE R1 CTLR CAN ONLY HAVE 2 ACFT ESTABLISHED ON THAT FINAL APCH COURSE. IF R1 HAS TO PROVIDE 7 MI; HE HAS TO ESTABLISH THE ACFT IN TRAIL USING MORE THAN 7 MI TO ALLOW FOR COMPRESSION. FOR EXAMPLE; 2 B757'S ON FINAL; THE FIRST ONE WILL START REDUCING AT THE FAF WHILE THE OTHER WILL BE AT 170 KTS. THE R1 CTLR WILL NEED TO ESTABLISH THEM AT LEAST 8 MI APART. SAME SCENARIO BUT WITH A C402 IN FRONT OF THE B757. THE C402 CAN REDUCE TO LESS THAN 90 KTS. THE R1 CTLR WOULD NEED TO ESTABLISH THE B757 AT LEAST 9 MI BEHIND THE CESSNA. ALL OF THIS CONSTITUTES AN INCREASE OF WORKLOAD AND A DECREASE IN SAFETY.
Data retrieved from NASA's ASRS site as of January 2009 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.