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Flight crew of medium large transport high wing type aircraft protested minimum wake turbulence separation from takeoff of heavy widebody transport type aircraft.
| Attributes | |
| ACN | 112239 |
| Time | |
| Date | 198905 |
| Day | Mon |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | atc facility : lax |
| State Reference | CA |
| Altitude | agl bound lower : 0 agl bound upper : 0 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Operator | common carrier : air carrier |
| Make Model Name | Medium Large Transport |
| Navigation In Use | Other |
| Flight Phase | climbout : takeoff ground : preflight ground other : taxi |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 150 flight time total : 6000 |
| ASRS Report | 112239 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : instrument pilot : commercial |
| Events | |
| Anomaly | other anomaly other |
| Independent Detector | other flight crewa |
| Resolutory Action | other |
| Consequence | faa : reviewed incident with flight crew |
| Supplementary | |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | other |
| Situations | |
| ATC Facility | procedure or policy : unspecified |
Narrative:
We were #2 for takeoff on 24L at lax behind heavy widebody transport aircraft. We were asked to position and hold, then widebody transport took off. We received takeoff clearance 1 min 30 second following widebody transport roll. Definitely insufficient wake turbulence separation. An unsafe situation perpetrated by tower. We did not take off, needless to say. We taxied clear and waited for next lot. Quite obvious tower was expediting takeoff sequence in total disregard of safety and common sense. Later obtained information on widebody transport flight via ZOA. Flight weighted 730,000 pounds at takeoff. Later yet, spoke to lax tower supervisor. His reply was 5 mi in trail separation is criteria for wake turbulence. Don't understand how widebody transport can attain 5 mi 1.5 min from brake release? Tower is basing operating procedure on minimum safe limits, thereby placing burden of ensuring reasonable safety on pilot. This is acceptable if dealing with experienced prudent individual, unacceptable with inexperienced pilot. In other words, conditions are being created for an accident.
Original NASA ASRS Text
Title: FLT CREW OF MLG HIGH WING TYPE ACFT PROTESTED MINIMUM WAKE TURBULENCE SEPARATION FROM TKOF OF HVY WDB TYPE ACFT.
Narrative: WE WERE #2 FOR TKOF ON 24L AT LAX BEHIND HVY WDB ACFT. WE WERE ASKED TO POSITION AND HOLD, THEN WDB TOOK OFF. WE RECEIVED TKOF CLRNC 1 MIN 30 SEC FOLLOWING WDB ROLL. DEFINITELY INSUFFICIENT WAKE TURB SEPARATION. AN UNSAFE SITUATION PERPETRATED BY TWR. WE DID NOT TAKE OFF, NEEDLESS TO SAY. WE TAXIED CLEAR AND WAITED FOR NEXT LOT. QUITE OBVIOUS TWR WAS EXPEDITING TKOF SEQUENCE IN TOTAL DISREGARD OF SAFETY AND COMMON SENSE. LATER OBTAINED INFO ON WDB FLT VIA ZOA. FLT WEIGHTED 730,000 LBS AT TKOF. LATER YET, SPOKE TO LAX TWR SUPVR. HIS REPLY WAS 5 MI IN TRAIL SEPARATION IS CRITERIA FOR WAKE TURB. DON'T UNDERSTAND HOW WDB CAN ATTAIN 5 MI 1.5 MIN FROM BRAKE RELEASE? TWR IS BASING OPERATING PROC ON MINIMUM SAFE LIMITS, THEREBY PLACING BURDEN OF ENSURING REASONABLE SAFETY ON PLT. THIS IS ACCEPTABLE IF DEALING WITH EXPERIENCED PRUDENT INDIVIDUAL, UNACCEPTABLE WITH INEXPERIENCED PLT. IN OTHER WORDS, CONDITIONS ARE BEING CREATED FOR AN ACCIDENT.
Data retrieved from NASA's ASRS site as of August 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.