AN ACR BA41 FLC HAD DIFFICULTY STEERING THE ACFT ON TAXI OUT AND THEY ALSO WERE RECEIVING AN INTERMITTENT STALL WARNING INDICATION. AFTER RETURNING TO THE GATE THEY DISCOVERED THAT THE ACFT WAS MUCH FURTHER TOWARD THE AFT CENTER OF GRAVITY LIMITS THAN ORIGINALLY CALCULATED.
Synopsis
AN ACR BA41 FLC HAD DIFFICULTY STEERING THE ACFT ON TAXI OUT AND THEY ALSO WERE RECEIVING AN INTERMITTENT STALL WARNING INDICATION. AFTER RETURNING TO THE GATE THEY DISCOVERED THAT THE ACFT WAS MUCH FURTHER TOWARD THE AFT CENTER OF GRAVITY LIMITS THAN ORIGINALLY CALCULATED.
Narrative
THIS FLT WAS SCHEDULED OUT OF IAD FOR JFK AT XA:00. THE CREW HAD ALREADY FLOWN ONE ROUND TRIP EARLIER WITH THE ACFT AND WAS READY FOR PAX EARLY. PAX ARRIVED AT THE MINIMUM REQUIRED TIME. THE BAGGAGE LOADING AND COUNT WAS DELAYED -- WITH THE BAGGAGE FORM GETTING TO THE CREW LATE. WANTING TO MAKE AN ON TIME TKOF; WE COMPLETED ALL OUR CALCULATIONS AS QUICKLY AS POSSIBLE. AFTER WE HANDED THE FORMS OUTSIDE AND CLOSED THE DOOR; RAMP INFORMED US THEY HAD PUT TWO MORE CHECKED BAGS INTO THE ACFT. WE RECOVERED OUR PAPERWORK AND MADE THE NECESSARY CORRECTIONS. WHILE TAXIING OUT TO RWY AT IAD; THE STALL LIGHTS ON THE CAP PANEL MOMENTARILY FLASHED ON AND OFF. THIS OCCURRED TWICE DURING TAXI. WE REFERRED TO THE QRH AND RECHECKED CIRCUIT BREAKERS. NO OTHER INDICATIONS OCCURRED AT THIS TIME SO I ASSUMED IT WAS A MALFUNCTIONING STALL SYSTEM. WE DECIDED TO RETURN TO THE GATE TO HAVE MAINTENANCE INVESTIGATE. WHILE TAXIING BACK; I NOTICED THE NOSEWHEEL STEERING WAS BECOMING INTERMITTENT. I DECIDED TO STOP THE ACFT ON TXWY Z JUST N OF TXWY A AND HAVE MAINT INVESTIGATE AND POSSIBLY TOW US. OUR WT AND BAL CG CALCULATIONS SHOWED US IN THE MIDDLE OF THE CG ENVELOPE; SO MY FIRST CONCERN WAS A MALFUNCTIONING NOSEWHEEL SQUAT SWITCH. AS A PRECAUTION THE FO ALSO DOUBLE CHECKED HIS WT AND BAL CALCULATIONS. WHEN MAINT ARRIVED; THEY INDICATED THAT THE NOSEWHEEL WAS CONSIDERABLY EXTENDED. I ASKED THE FA TO MOVE TWO PAX TO EMPTY SEATS IN THE FORWARD PORTION OF THE CABIN. MAINT INDICATED THE STRUT HAD COMPRESSED SOME; SO I DECIDED TO TAXI BACK TO THE GATE. NOSEWHEEL STEERING WORKING FINE. ONCE IN THE GATE; I REQUESTED MAINT TO CHECK THE NOSEWHEEL SQUAT SWITCH; STALL SYSTEM AND TO HAVE THE BAGGAGE COUNT RE-VERIFIED. AT THE TIME THE FO INDICATED TO ME THAT THERE WAS A 350 LB ERROR IN HIS CALCULATIONS OF THE BAGGAGE. WE RE-SPUN HIS 'CORRECTED' CALCULATIONS AND FOUND THE CG TO BE FURTHER AFT; BUT NOT INTO ANY CAUTION ZONE OR AFT LIMITATION. NO WEIGHT OR CG LIMITATIONS WERE EXCEEDED. THE RAMP INSPECTORS INFORMED ME THAT THE BAGGAGE COUNT WAS CORRECT. THEY INDICATED CONCERN THAT SOME HEAVY BAGS WERE INDEED 'VERY HEAVY' AND WERE LOADED IN THE 'AFT END' OF THE COMPARTMENT. USING THE NEW BAGGAGE COUNT FORM AND THE REDISTRIBUTED PAX SEATING; WE RECALCULATED OUR WEIGHT AND BALANCE. SUBSEQUENT TAXI AND TKOF OCCURRED WITHOUT INCIDENT. I AM CONCERNED BY TWO ISSUES: THE COMPANY'S WT AND BAL PROC USES MULTIPLE FORMS. THE ACTUAL ACFT CG IS COMPUTED USING A 'CIRCULAR SLIDE RULE' TYPE CALCULATOR. NUMBERS AND TOTALS FROM THE FA; RAMP HANDLERS AND CALCULATOR ARE TRANSFERRED TO THE DISPATCH RELEASE; WHICH IS FILLED OUT AND SIGNED BY THE CAPT. THE ACFT FLT STANDARDS MANUAL REITERATES THE FARS; STATING THAT THE CAPT IS RESPONSIBLE FOR THE WT AND BAL OF THE ACFT. WHILE THE MANUAL DOES DISCUSS HOW TO COMPLETE THE WT AND BAL WORKSHEET AND DISPATCH RELEASE; IT DOES NOT DISCUSS HOW TO COMPLETE THE RAMP FORM. NOR DOES THE MANUAL SPECIFY 'WHO' ACCOMPLISHES ANY THESE CALCULATIONS. TOTALS ARE TRANSFERRED TO THE DISPATCH RELEASE WHERE THE CAPT WORKS THE CG CALCULATOR AND SIGNS FOR THE WT AND BAL. I AM CONCERNED THAT HAVING TO MANIPULATE FORMS COMBINED WITH THE COMPANY'S INTENSE PRESSURE FOR ON-TIME TKOFS CAN ONLY LEAD TO ERRORS THAT WILL NOT BE CAUGHT BY THOUGHTFUL OR PROCEDURAL REVIEW. BECAUSE OF THE PRESSURE TO GET THE DOOR CLOSED AND ENG STARTED WITHIN FIVE MINUTES OF SCHEDULED DEP TIME; THE FO'S CALCULATIONS WERE NOT REVIEWED. EVEN THOUGH THE 'CORRECTED' ACFT CENTER OF GRAVITY SHOWED THE ACFT TO BE IN SAFE LIMITS; WE WERE AFT OF THAT CALCULATED. THIS IS BECAUSE THE COMPANY CONSIDERS 'HEAVY OVERSIZED' BAGS TO WEIGH ONLY 50 LBS EACH. MANY OF THESE BAGS ARE TRANSFERS FROM ACR X CONNECTING PAX. ACR X CONSIDERS A 'HEAVY BAG' TO WEIGH 75 LBS. SEVEN (7) OF THE BAGS ON OUR AIRPLANE WERE LISTED AS 'OVERSIZED HEAVY.' IF THE BAGS WERE CALCULATED AT 75 LBS EACH; THE EXTRA CG MOMENT WOULD HAVE PLACED THE ACFT CG IN THE AFT 'CAUTION ZONE.' I WOULD HAVE THEN REDISTRIBUTED PAX TO ACHIEVE A SAFE ACFT CG. THECOMPANY ALSO MIXES THE CONCEPTS OF 'OVERSIZED' AND 'HEAVY' BAGS. THESE BAGS ARE NOT IDENTIFIED IN ANY WAY AND IT IS A JUDGEMENT CALL ON THE PART OF THE RAMP AGENT OR PLT TO CLASSIFY THEM AS SUCH. 'HEAVY' BAGS ARE SPECIALLY IDENTIFIED (RED TAG). EVEN THOUGH OUR PARTNER ACR X'S POLICY STATES THAT A BAG MUST WEIGH A MINIMUM OF 75 LBS TO BE RED TAGGED; OUR COMMUTER ACR COUNTS THEM AS ONLY 50 LBS EACH. THE COMPANY DOES NOT HAVE SCALES AT STATIONS FOR WEIGHING. THERE IS NO OTHER REFERENCE TO THIS OPTION IN THE ACFT'S FLT STANDARDS MANUAL OR COMPANY FLT OPS MANUAL. I AM CONCERNED THAT COMPANY PROCS DO NOT ACCOUNT FOR THE REALITIES OF OUR OPERATING CUSTOMER BASE AND DO NOT ACCOUNT FOR PLT ACTIONS OR REQUIREMENTS TO STAY ON-TIME.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.